U.S. patent application number 16/238995 was filed with the patent office on 2019-07-11 for biochar as a microbial carrier.
The applicant listed for this patent is Cool Planet Energy Systems, Inc.. Invention is credited to Richard Wilson Belcher, Brian Buege, Michael C. Cheiky, Mark L. Jarand, Han Suk Kim, Ronald A. Sills.
Application Number | 20190210935 16/238995 |
Document ID | / |
Family ID | 59065069 |
Filed Date | 2019-07-11 |
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United States Patent
Application |
20190210935 |
Kind Code |
A1 |
Belcher; Richard Wilson ; et
al. |
July 11, 2019 |
BIOCHAR AS A MICROBIAL CARRIER
Abstract
The invention relates to a microbial delivery system where
biochar acts as a carrier for microbes.
Inventors: |
Belcher; Richard Wilson;
(Oxnard, CA) ; Kim; Han Suk; (Thousand Oaks,
CA) ; Buege; Brian; (Centennial, CO) ; Cheiky;
Michael C.; (US) ; Sills; Ronald A.; (Houston,
TX) ; Jarand; Mark L.; (Rotorua, NZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Cool Planet Energy Systems, Inc. |
Greenwood Village |
CO |
US |
|
|
Family ID: |
59065069 |
Appl. No.: |
16/238995 |
Filed: |
January 3, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15393214 |
Dec 28, 2016 |
10173937 |
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16238995 |
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15350920 |
Nov 14, 2016 |
10093588 |
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15393214 |
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14385986 |
Dec 23, 2014 |
9493380 |
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PCT/US12/39862 |
May 29, 2012 |
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15350920 |
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13154213 |
Jun 6, 2011 |
8317891 |
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14385986 |
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15156256 |
May 16, 2016 |
9809502 |
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15393214 |
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14873053 |
Oct 1, 2015 |
10252951 |
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15393214 |
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14036480 |
Sep 25, 2013 |
9359268 |
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15393214 |
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13189709 |
Jul 25, 2011 |
8568493 |
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14036480 |
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62271486 |
Dec 28, 2015 |
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62290285 |
Feb 2, 2016 |
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62344865 |
Jun 2, 2016 |
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62432253 |
Dec 9, 2016 |
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62162219 |
May 15, 2015 |
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62058445 |
Oct 1, 2014 |
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62058472 |
Oct 1, 2014 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C12N 1/14 20130101; C10B
53/02 20130101; C05G 3/00 20130101; C10B 57/02 20130101; C05F 11/08
20130101; C12N 11/12 20130101; Y02E 50/14 20130101; C01B 32/05
20170801; Y10S 71/903 20130101; C12N 1/20 20130101; Y02E 50/10
20130101; C05D 9/00 20130101; C05G 5/40 20200201; C09K 17/40
20130101; C05F 11/00 20130101; C09K 17/04 20130101; C05G 5/00
20200201; C12N 1/16 20130101; Y02P 20/145 20151101; C05F 11/02
20130101; C09K 17/02 20130101; C05F 11/02 20130101; C05F 11/08
20130101 |
International
Class: |
C05F 11/08 20060101
C05F011/08; C12N 1/20 20060101 C12N001/20; C01B 32/05 20060101
C01B032/05; C12N 1/14 20060101 C12N001/14; C12N 11/12 20060101
C12N011/12; C12N 1/16 20060101 C12N001/16; C09K 17/04 20060101
C09K017/04; C05D 9/00 20060101 C05D009/00; C05F 11/00 20060101
C05F011/00; C10B 57/02 20060101 C10B057/02; C10B 53/02 20060101
C10B053/02; C09K 17/02 20060101 C09K017/02; C05G 3/00 20060101
C05G003/00; C05F 11/02 20060101 C05F011/02 |
Claims
1. A microbial delivery system comprising: biochar having pores;
and microbes retained on the surface or in the pores of the
biochar.
2. The delivery system of claim 1, where at least some of the
microbes are inoculated into the pores of the biochar.
3. The delivery system of claim 2, where the microbes are
inoculated into the pores of the biochar using mechanical,
chemical, or biological assistance to move the microbes either into
the pores of the biochar or onto the surfaces of the biochar.
4. The delivery system of claim 3 where the microbes are inoculated
into the pores of the biochar using the application of positive or
negative pressure.
5. The delivery system of claim 3 where the microbes are inoculated
into the pores of the biochar using a surfactant.
6. The delivery system of claim 1 where the microbes are retained
by the biochar through mixing the biochar and microbes
together.
7. The delivery system of claim 6 where the microbes are retained
on the biochar by suspending the microbes in liquid and depositing
the microbes on the biochar.
8. The delivery system of claim 1 where the microbes retained by
the biochar are selected from the group consisting of: Bacillus,
Pseudomonas, Rhizobium, Burkholderia, Achromobacter, Agrobacterium,
Microccocus, Aereobacter, Flavobacterium, Erwinia, Klebsiella, and
Enterobacter, including Bacillus mucilaginosus, Bacillus edaphicus,
Bacillus circulans, Paenibacillus spp., Acidothiobacillus
ferrooxidans, Pseudomonas cepacia, Burkholderia cepacia, Klebsiella
varticola, Pantoea aggioinerans; fungi such as Glomus mosseae,
Glomus intraradices, Aspergillus terreus and Aspergillus niger.
9. The delivery system of claim 1 where the biochar is treated
biochar.
10. The delivery system of claim 9 where the biochar has been
treated to alter one or more of the following properties of the
biochar: pH; hydrophobicity; hydrophilicity; ability of the biochar
to hold moisture; ability of the biochar to retain and exchange
certain types of nutrients; ion exchange capacity; physical
protection from environmental hazards or protozoa; presence or
absence of nutrients, micronutrients, or sources of metabolic
carbon; or ability of the biochar to host other symbiotic microbes
or plant systems.
11. The delivery system of claim 1, where at least some of the
microbes are retained on the biochar through integrated growth with
the biochar.
12. A method for delivering microbes into an environment, the
method comprising combining biochar and microbes in the
environment, where the biochar has been treated to have suitable
properties for the microbes in the environment in which the biochar
and microbes are combined.
13. Biochar having pores where pores are filled with a media
containing microbes, where the media is infused into the pores of
the biochar.
14. The biochar of claim 13 where the microbes includes
microorganisms selected from the group consisting of: Bacillus,
Pseudomonas, Rhizobium, Burkholderia, Achromobacter, Agrobacterium,
Microccocus, Aereobacter, Flavobacterium, Erwinia, Klebsiella, and
Enterobacter, including Bacillus mucilaginosus, Bacillus edaphicus,
Bacillus circulans, Paenibacillus spp., Acidothiobacillus
ferrooxidans, Pseudomonas cepacia, Burkholderia cepacia, Klebsiella
variicola, Pantoea agglomerans; fungi such as Glomus mosseae,
Glomus intraradices, Aspergillus terreus and Aspergillus niger.
15. The biochar of claim 13 where the media is infused into the
pores of the biochar using positive or negative pressure.
16. The biochar of claim 13 where the media is infused into the
pores of the biochar using a surfactant.
17. The biochar of claim 16 where the surfactant treatment
comprises adding 1% surfactant to the media.
18. The biochar of claim 13 where the pores of the biochar are
treated prior to infusion with the media.
19. The biochar of claim 13 where the moisture content of the pores
of the biochar are adjusted prior to infusion with the media.
20. Biochar for use in agricultural, remediation, public health, or
animal application, the biochar comprising a porous carbonaceous
particle that has been treated and/or mixed with media containing
microbes, whereby the porous carbonaceous particle after treatment
and/or mixing has retained the media in at least some of the pores
of the porous carbonaceous particle.
21. The biochar of claim 20 where the microbes are microorganisms
selected from the group consisting of: Bacillus, Pseudomonas,
Rhizobium, Burkholderia, Achromobacter, Agrobacterium, Microccocus,
Aereobacter, Flavobacterium, Erwinia, Klebsiella, and Enterobacter,
including Bacillus mucilaginosus, Bacillus edaphicus, Bacillus
circulans, Paenibacillus spp., Acidothiobacillus ferrooxidans,
Pseudomonas cepacia, Burkholderia cepacia, Klebsiella variicola,
Pantoea agglomerans; fungi such as Glomus mosseae, Glomus
intraradices, Aspergillus terreus and Aspergillus niger.
22. A method for creating enhanced biochar, the method comprising
the steps of infusing media containing microbes into the pores of
biochar.
23. The method of claim 22 where the media is infused into the
pores of the biochar using positive or negative pressure.
24. The method of claim 22 where the media is infused into the
pores of the biochar using a surfactant.
25. The method of claim 22 where the media includes microorganisms
selected from the group consisting of: Bacillus, Pseudomonas,
Rhizobium, Burkholderia, Achromobacter, Agrobacterium, Microccocus,
Aereobacter, Flavobacterium, Erwinia, Klebsiella, and Enterobacter,
including Bacillus mucilaginosus, Bacillus edaphicus, Bacillus
circulans, Paenibacillus spp., Acidothiobacillus ferrooxidans,
Pseudomonas cepacia, Burkholderia cepacia, Klebsiella variicola,
Pantoea agglomerans; fungi such as Glomus mosseae, Glomus
intraradices, Aspergillus terreus and Aspergillus niger.
26. A methods for integrating a microbial community with a biochar
particle, the method selected from the group consisting of: while
under vacuum, pulling the microbial solution through a treated
biochar bed that is resting on a membrane filter; spraying a
microbial solution on top of a treated biochar bed; lyophilizing a
microbial solution and then blending the freeze dried solution with
the treated biochar; again infusing, the treated biochar with a
microbial solution; adding treated biochar to a growth medium,
inoculating with the microbe, and incubating to allow the microbe
to grow in said biochar containing medium; infusing, as defined
previously, the biochar with a food source and then introducing the
substrate infused biochar to a microbe and incubating to allow the
microbes to grow; blending commercially available strains in dry
form with treated biochar; adding the treated biochar to a
microbial solution and then centrifuging at a high speed,
potentially with a density gradient in order to promote the biochar
to spin down with the microbes; densely packing a column with
treated biochar and then gravity flowing a microbial solution
through the column and possibly repeating this multiple times; or
adding the microbe to a solution based binder that is well known to
enter the treated biochar pores and then adding said solution to
the treated biochar.
27. The method of claim 26 where biochar is sterilized before being
infused with the microbial community.
28. The method of claim 26 where the microbial community includes a
microorganism selected from the group consisting of: Bacillus,
Pseudomonas, Rhizobium, Burkholderia, Achromobacter, Agrobacterium,
Microccocus, Aereobacter, Flavobacterium, Erwinia, Klebsiella, and
Enterobacter, including Bacillus mucilaginosus, Bacillus edaphicus,
Bacillus circulans, Paenibacillus spp., Acidothiobacillus
ferrooxidans, Pseudomonas cepacia, Burkholderia cepacia, Klebsiella
variicola, Pantoea agglomerans; fungi such as Glomus mosseae,
Glomus intraradices, Aspergillus terreus and Aspergillus niger.
29. The biochar of claim 20 where the biochar has been treated to
alter one or more of the following properties of the biochar: pH;
hydrophobicity; hydrophilicity; ability of the biochar to hold
moisture; ability of the biochar to retain and exchange certain
types of nutrients; ion exchange capacity; physical protection from
environmental hazards or protozoa; presence or absence of
nutrients, micronutrients, or sources of metabolic carbon; or
ability of the biochar to host other symbiotic microbes or plant
systems.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of and claims priority to
U.S. patent application Ser. No. 15/393,214 filed Dec. 28, 2016
titled BIOCHAR AS A MICROBIAL CARRIER, which claims priority to
U.S. Provisional Patent Application Ser. No. 62/271,486 filed on
Dec. 28, 2015 titled ADDITIVE INFUSED BIOCHARS, U.S. Provisional
Patent Application Ser. No. 62/290,285 filed on Feb. 2, 2016 titled
ADDITIVE INFUSED BIOCHARS, U.S. Provisional Patent Application Ser.
No. 62/344,865 filed on Jun. 2, 2016 titled MINERAL SOLUBILIZING
MICROORGANISMS INFUSED BIOCHARS and U.S. Provisional Patent
Application Ser. No. 62/432,253 filed on Dec. 9, 2016 titled
ADDITIVE INFUSED BIOCHARS, which U.S. patent application Ser. No.
15/393,214 filed Dec. 28, 2016 titled BIOCHAR AS A MICROBIAL
CARRIER is a continuation-in-part of U.S. patent application Ser.
No. 15/350,920 filed on Nov. 14, 2016 titled METHOD FOR ENHANCING
SOIL GROWTH USING BIO-CHAR (now U.S. Pat. No. 10,093,588 that
issued on Oct. 9, 2018), which is a continuation of U.S. patent
application Ser. No. 14/385,986 filed on May 29, 2012, titled
METHOD FOR ENHANCING SOIL GROWTH USING BIO-CHAR (now U.S. Pat. No.
9,493,380 that issued on Nov. 15, 2016), which is a 371 national
stage filing of PCT US12/39862 filed May 29, 2012 titled METHOD FOR
ENHANCING SOIL GROWTH USING BIO-CHAR, which is a continuation of
U.S. patent application Ser. No. 13/154,213 filed on Jun. 6, 2011,
titled METHOD FOR ENHANCING SOIL GROWTH USING BIO-CHAR (now U.S.
Pat. No. 8,317,891 that issued on Nov. 27, 2012), which U.S. patent
application Ser. No. 15/393,214 filed Dec. 28, 2016 titled BIOCHAR
AS A MICROBIAL CARRIER is also a continuation-in-part of U.S.
patent application Ser. No. 15/156,256, filed on May 16, 2016,
titled ENHANCED BIOCHAR (now U.S. Pat. No. 9,809,502 that issued
Nov. 7, 2017), which claims priority to U.S. Provisional Patent
Application No. 62/162,219, filed on May 15, 2015, titled ENHANCED
BIOCHAR, which U.S. patent application Ser. No. 15/393,214 filed
Dec. 28, 2016 titled BIOCHAR AS A MICROBIAL CARRIER is also a
continuation-in-part of U.S. patent application Ser. No. 14/873,053
filed on Oct. 1, 2015, titled BIOCHARS AND BIOCHAR TREATMENT
PROCESSES, which claims priority to U.S. Provisional Patent
Application No. 62/058,445, filed on Oct. 1, 2014, titled METHODS,
MATERIALS AND APPLICATIONS FOR CONTROLLED POROSITY AND RELEASE
STRUCTURES AND APPLICATIONS and U.S. Provisional Patent Application
No. 62/058,472, filed on Oct. 1, 2014, titled HIGH ADDITIVE
RETENTION BIOCHARS, METHODS AND APPLICATIONS, and which U.S. patent
application Ser. No. 15/393,214 filed Dec. 28, 2016 titled BIOCHAR
AS A MICROBIAL CARRIER is also a continuation-in-part of U.S.
patent application Ser. No. 14/036,480, filed on Sep. 25, 2013,
titled METHOD FOR PRODUCING NEGATIVE CARBON FUEL (now U.S. Pat. No.
9,359,268 that issued Jun. 7, 2016), which is a continuation of
U.S. patent application Ser. No. 13/189,709, filed on Jul. 25, 2011
(now U.S. Pat. No. 8,568,493), all of the above of which are
incorporated in their entirety by reference in this
application.
FIELD OF INVENTION
[0002] The invention relates to porous carbonaceous structures
having increased capabilities to retain additives for use in
applications, including, but not limited to, agricultural
applications. These additives include but are not limited to
beneficial nutrients, substances, microbes, or enzymes. The
additives can be incorporated with the biochar in various ways,
including but not limited to infusing the biochar with the
additives to provide for the gradual delivery of the additive to
the surrounding environment, such as soil.
BACKGROUND
[0003] During the last decades, soil degradation has increased due
to deforestation, agricultural activities, industrial activities,
vegetation overexploitation and excessive grazing. To avoid and
potentially reverse soil degradation, many different types of soil
enhancers have been developed and are already being used today.
Among the most common soil enhancers are fertilizers. Fertilizers
improve the supply of nutrients in the soil, directly affecting
plant growth. However, despite the wide spread use of fertilizers,
conventional fertilizers are inefficient, particularly in soils
with low cation exchange capacities and humid climate conditions.
The demand for frequent application, susceptibility to being washed
out/leaching, and the need for nutrients to be constantly
replenished are a few of the many problems associated with
conventional fertilizers. Therefore, controlled released
fertilizers (CRF) have become the preferred type of fertilizers to
improve nutrient yield while minimizing losses. CRF's have the
ability to supply nutrients gradually to soil and plants over a
longer period of time. By coinciding with the nutrient requirements
of the plant, CRF's ensure improved effectiveness through
minimizing the losses between application and absorption, thus
avoiding losses by leaching, runoff, and nutrient
volatilization.
[0004] A second known type of soil enhancer consists of microbes,
such as beneficial fungi or plant growth promoting bacteria
("PGPB"). PGPB are rhizosphere-associated organisms that colonize
the rhizosphere and rhizoplane and improve plant growth when
artificially inoculated into soil. PGPB can both promote plant
growth and fight pathogenic fungi. Current methods for deploying
microbes into the environment often lead to the microbes being
compromised and even dying before they can be fully incorporated
into the environment. Thus a system or method to deploy them which
will better maintain their viability and effectiveness is needed
for the industry to fully realize the benefits of microbial
use.
[0005] A third known type of soil enhancer is biochar. Biochar has
been known for many years as a soil enhancer. It contains highly
porous, high carbon content material similar to the type of very
dark, fertile anthropogenic soil found in the Amazon Basin known as
Terra Preta, which has very high carbon content and historically
has been made from a mixture of charcoal, bone, and manure. Biochar
is created by the pyrolysis of biomass, which generally involves
heating and/or burning of organic matter, in a reduced oxygen
environment, at a predetermined rate. Such heating and/or burning
is stopped when the matter reaches a charcoal like stage. The
highly porous material of biochar is suited to host beneficial
microbes, retain nutrients, hold water, and act as a delivery
system for a range of beneficial compounds and additives suited to
specific applications.
[0006] Raw biochar, while known for its soil enhancing
characteristics, does not always benefit soil and, depending upon
the biomass from which the biochar is produced and the method of
production, can potentially be harmful to the soil, making it
unsuitable for various types of crops or other productive uses. In
particular, biochar can be detrimental, or even toxic, to 1) soil
microbes involved in nutrient transport to the plant; 2) plants and
3) humans. Biochars derived from different biomass or produced with
differing parameters, such as higher or lower pyrolysis temperature
or variations in residence time, will have different physical and
chemical properties and can behave quite differently when used in
agriculture. For example, biochar having pH levels too high,
containing too much ash, inorganics, or containing toxins or heavy
metal content too high can be harmful and/or have minimal benefit
to the soil and the plant life it supports. Biochar can also
contain unacceptable levels of residual organic compounds such as
acids, esters, ethers, ketones, alcohols, sugars, phenyls, alkanes,
alkenes, phenols, polychlorinated biphenyls or poly or mono
aromatic hydrocarbons which are either toxic or not beneficial to
plant or animal life.
[0007] Due to the unpredictable performance of biochar and its
potential to be detrimental to plant life and growth, it has mostly
been a scientific curiosity, not found wide spread use, not found
large scale commercial application, and has been relegated to small
niche applications. It is, however, known, as noted above, that
biochar, having certain characteristics can host beneficial
microbes, retain nutrients, hold water, and act as a delivery
system for a range of beneficial compounds suited to specific
applications. Thus, it has been a continued desire to capture the
beneficial soil enhancing characteristics of biochar in a more
consistent, predictable way. Biochar research has continued in an
attempt to harness biochar having predictable, controllable, and
beneficial results as a soil amendment for large scale
applications.
[0008] Additionally, attempts have been made to narrowly combine
the benefits of fertilizer with biochar by mixing it with, coating
it with or submersing it in the fertilizer. The results of these
attempts, however, have failed to adequately allow soil nutrient
exposure and plant nutrient uptake to occur over a longer period of
time throughout a growing season from the same application.
[0009] There are currently around 7 billion people in the world and
this is expected to increase to approximately 8 billion around the
year 2020. In light of both the expected worldwide population
increase and the increasing environmental damage caused by ever
greater levels of industrialization, it will become more and more
of a challenge to feed all of the world's people, a problem that
will only increase with time. Thus, a need exists, in order to feed
this growing population, for a method of combining the benefits of
fertilizer, beneficial fungi, PGPB or other additives with biochar
in a manner that reduces the cost and impact of the frequent
application of nutrients to the soil and increases agricultural
productivity in a sustainable and environmentally friendly
manner.
SUMMARY
[0010] The present invention relates to biochar having increased
capabilities to retain and then deploy additives more effectively.
The biochar may be infused with beneficial additives to allow for a
more gradual, prolonged release of the compounds to the soil. This
time release effect in agricultural applications can dramatically
reduce the need for high frequency application in the period
immediately following planting and can also increase plant growth
and sustain plant life. The present invention can be used in
connection with any type of beneficial additive--including, but not
limited to, plant nutrients, beneficial fungi, PGPB, hormones,
enzymes, bio pesticides, herbicides, fungicides, nematicides,
bacteriacides, fumigants among others additives, as will be
described more fully below. In addition, the biochar can make a
superior microbial carrier for various applications, including but
not limited to agriculture, as the properties of the biochar can
improve the viability of the microbes and their effectiveness after
deployment with the biochar.
[0011] The method includes producing an additive infused biochar
that may contain biochar, plant nutrients, beneficial fungi, PGPB
and/or other additives. The method includes impregnating at least
some of the pores of the biochar with liquid additives or additives
in liquid solution through an infusion process. The resulting
infused biochar provides for gradual and/or steady delivery of the
additives to the soil and plants. The utilization of additive
infused biochar allows the delivery of more nutrients or additives
per unit of biochar and also provides for a more gradual release of
the additives to the surrounding soil. In turn, this enables
different soils to provide an environment well suited to the long
term success of the desired plant. The use of additive infused
biochar results in visibly fuller plants, increases plant yield
with improved vitality and longevity that can be maintained with
less frequent additive application and reduced additive
effectiveness from leaching or runoff.
[0012] The present invention teaches treating the biochar in a
manner that forces, accelerates or assists the infusion of
additives into the pores of the biochar. Treatment in this manner
allows for the impregnation or inoculation of the pores of the
biochar with additives, which can be beneficial for the intended
use of the biochar.
[0013] In one example of an implementation of the present
invention, the method for treating the biochar includes placing
porous carbonaceous materials in a tank or chamber; adding an
additive solution to the tank; and changing the pressure in the
tank by, for example, placing the contents of the tank under a
partial vacuum. In this example, the additive solution may be added
to the tank either before the pressure change is applied or while
the pressure change is being applied. In addition to subjecting the
contents to a partial vacuum, the pores of the biochar may be
impregnated with the additive solution using a surfactant solution
(e.g., a liquid solution containing 0.1-20% surfactant) or
ultrasonic treatment, as will be further described below. Through
the above treatment methods, at least 10% or more of the pore
volume of the pores of the biochar material may be filled with the
additive solution within a time period where it would not otherwise
be possible to achieve the same results by simply contact or
immersion of the biochar with the additive solution alone.
[0014] Other devices, apparatus, systems, methods, features and
advantages of the invention are or will become apparent to one with
skill in the art upon examination of the following figures and
detailed description. It is intended that all such additional
systems, methods, features and advantages be included within this
description, be within the scope of the invention, and be protected
by the accompanying claims.
BRIEF DESCRIPTION OF THE FIGURES
[0015] The invention may be better understood by referring to the
following figures. The components in the figures are not
necessarily to scale, emphasis instead being placed upon
illustrating the principles of the invention.
[0016] FIG. 1 illustrates a cross-section of one example of a raw
biochar particle.
[0017] FIG. 2a is a SEM (10 KV.times.3.00K 10.0 .mu.m) of pore
morphology of treated biochar made from pine.
[0018] FIG. 2b is a SEM (10 KV.times.3.00K 10.0 .mu.m) of pore
morphology of treated biochar made from birch.
[0019] FIG. 2c is a SEM (10 KV.times.3.00K 10.0 .mu.m) of pore
morphology of treated biochar made from coconut shells.
[0020] FIG. 3 is a chart showing porosity distribution of various
biochars.
[0021] FIG. 4 is a flow chart process diagram of one implementation
of a process for treating the raw biochar in accordance with the
invention.
[0022] FIG. 4a illustrates a schematic of one example of an
implementation of a biochar treat processes that that includes
washing, pH adjustment and moisture adjustment.
[0023] FIG. 4b illustrates yet another example of an implementation
of a biochar treatment processing that includes inoculation.
[0024] FIG. 5 is a schematic flow diagram of one example of a
treatment system for use in accordance with the present
invention.
[0025] FIG. 6 is a chart showing the water holding capacities of
treated biochar as compared to raw biochar and sandy clay loam soil
and as compared to raw biochar and sunshine potting soil.
[0026] FIG. 7 illustrates the different water retention capacities
of raw biochar versus treated biochar measured gravimetrically.
[0027] FIG. 8 is a chart showing the retained water in vacuum
impregnated biochar over other biochars after a seven week
period.
[0028] FIG. 9 is a chart showing the weight loss of treated
biochars versus raw biochar samples when heated at varying
temperatures using a TGA testing method.
[0029] FIG. 10 illustrates the plant available water in raw
biochar, versus treated biochar and treated dried biochar.
[0030] FIG. 11 is a graph showing the pH of various starting
biochars that were made from different starting materials and
pyrolysis process temperatures.
[0031] FIG. 12 is a chart showing various pH ranges and germination
for treated biochars.
[0032] FIG. 13 is a Thermogravimetric Analysis (TGA) plot showing
the measurement of water content, heavy organics and light organics
in a sample.
[0033] FIG. 14 is a chart showing the impact of treatment on pores
sizes of biochar derived from coconut.
[0034] FIG. 15 is a chart showing the impact of treatment on pores
sizes of biochar derived from pine.
[0035] FIG. 16 is a chart showing the measured hydrophobicity index
raw biochar, vacuum treated biochar and surfactant treated
biochar.
[0036] FIG. 17 is a flow diagram showing one example of a method
for infusing biochar.
[0037] FIG. 18 illustrates the improved liquid content of biochar
using vacuum impregnation as against soaking the biochar in
liquid.
[0038] FIG. 19a is a chart comparing total retained water of
treated biochar after soaking and after vacuum impregnation.
[0039] FIG. 19b is a chart comparing water on the surface,
interstitially and in the pores of biochar after soaking and after
vacuum impregnation.
[0040] FIG. 20 illustrates how the amount of water or other liquid
in the pores of vacuum processed biochars can be increased varied
based upon the applied pressure.
[0041] FIG. 21 illustrates the effects of NPK impregnation of
biochar on lettuce yield.
[0042] FIG. 22 is a chart showing nitrate release curves of treated
biochars infused with nitrate fertilizer.
[0043] FIGS. 23 and 24 are images that show how different sized
bacteria will fit in different biochar pore size structures.
[0044] FIG. 25 illustrates release rate data verse total pore
volume data for both coconut shell and pine based treated biochars
inoculated with a releasable bacteria.
[0045] FIG. 26 is a chart comparing examples of biochars.
[0046] FIGS. 27a, 27b, 27c are charts comparing different examples
of biochars.
[0047] FIG. 28 is a chart comparing shoot biomass when the biochar
added to a soilless mix containing soybean seeds is treated with
microbial product containing bradyrhizobium japonicum, and when it
is untreated.
[0048] FIG. 29 shows the comparison of root biomass in a treated
verses an untreated environment.
[0049] FIG. 30 is a chart comparing the nitrogen levels when the
biochar is inoculated with the rhizobial inoculant verses when it
is not inoculated.
[0050] FIG. 31 illustrates the three day release rates of water
infused biochar compared to other types of biochar.
[0051] FIG. 32a is a SEM (10 KV.times.3.00K 10.0 .mu.m) of pore
morphology of raw biochar.
[0052] FIG. 32b is a SEM (10 KV.times.3.00K 10.0 .mu.m) of pore
morphology of raw biochar of FIG. 32a after it has been infused
with microbial species.
[0053] FIG. 32c is a SEM (10 KV.times.3.00K 10.0 .mu.m) of a pore
morphology of another example of raw biochar of FIG. 17a after it
has been infused with microbial species.
[0054] FIG. 33 contains charts illustrating improved results
obtained through the use of biochars.
[0055] FIG. 34 is an example of carbon dioxide production captured
as a continuous gas bubble in BGB (left two tubes) and LTB (right
two tubes) growth medium.
[0056] FIGS. 35 and 36 illustrate improved growth rates of colonies
of Streptomyces lydicus using biochars.
DESCRIPTION OF THE INVENTION
[0057] As illustrated in the attached figures, the present
invention relates to biochar having increased capabilities to
retain and then deploy additives more effectively. In addition, it
includes additive infused biochars and methods for infusing
biochars with additives that allow for the release of the additives
into the environment gradually. When used in agricultural
applications, the gradual release of the additive into the soil,
can result in an increase of plant growth, vigor, or survivability,
while minimizing the loss of beneficial compounds in the root zone.
In particular, the biochar can make a superior microbial carrier
for various applications, including but not limited to agriculture,
as the properties of the biochar can improve the viability of the
microbes and their effectiveness after deployment with the biochar.
This present invention of the biochar as a microbial carrier can
either be or not be in conjunction with the invention of the
additive infusion, in which the additive infused is either the
microbe itself or something else. As described below, through
treatment, the properties of the raw biochar can be modified to
significantly increase the biochar's ability to retain water,
nutrients and additives useful for an end application while also,
in many cases, creating an environment beneficial to
microorganisms. Generally, for agricultural applications, such
enhanced abilities could include holding water, and nutrients, e.g.
fertilizer, or removing compounds, such as volatile organic
compounds (VOCs), that may react with or negatively impact either
the additive itself or microbial or plant life in general.
[0058] For example, through treatment, in addition to nutrients,
other material additives, e.g., beneficial fungi, PGPB, herbicides
and pesticides, can be utilized and benefit from the increased
holding and retention capacities of the treated biochar. For
certain biochar, the processing can also ensure that properties of
the biochar, including its pH, used in the present application is
suitable for creating conditions beneficial for plant or microbial
growth, which has been a known challenge for raw biochars.
[0059] Generally, treated biochar of the present invention can be
used throughout the world, in numerous soil types, agricultural
applications, horticultural, large and small scale farming, organic
farming, and in a variety of soil management applications and
systems, and combinations and variations of these. Examples of
these applications include for example, use in acidic and highly
weathered tropical field soils, use in temperate soils of higher
fertility, use in large commercial applications, use for the
production of large scale crops such as, soybean, corn, sugarcane
and rice, in forestry applications, for golf courses (e.g., greens,
fairways), for general purpose turf grasses, wine grapes, table
grapes, raisin grapes, fruit and nut trees, ground fruits (e.g.,
strawberries, blueberries, blackberries), row crops (e.g.,
tomatoes, celery, lettuce, leafy greens), root crops (e.g., tubers,
potatoes, beets, carrots), mushrooms, and combinations and
variations of these and other agricultural applications. As
discussed in more detail below, biochar treated in this way may
also be used in other applications, such as animal feed,
composting, water treatment, and heavy metal remediation, to name a
few.
[0060] For purposes of this application, the term "biochar" shall
be given its broadest possible meaning and shall include any solid
carbonaceous materials obtained from the pyrolysis, torrefaction,
gasification or any other thermal and/or chemical conversion of a
biomass. For purposes of this application, the solid carbonaceous
material may include, but not be limited to, BMF char disclosed and
taught by U.S. Pat. No. 8,317,891, which is incorporated into this
application by reference. Pyrolysis is generally defined as a
thermochemical decomposition of organic material at elevated
temperatures in the absence of, or with reduced levels of oxygen.
When the biochar is referred to as "treated" or undergoes
"treatment," it shall mean raw, pyrolyzed biochar that has
undergone additional physical, biological, and/or chemical
processing.
[0061] As used herein, unless specified otherwise, the terms
"carbonaceous", "carbon based", "carbon containing", and similar
such terms are to be given their broadest possible meaning, and
would include materials containing carbon in various states,
crystallinities, forms and compounds.
[0062] As used herein, unless stated otherwise, room temperature is
25.degree. C. And, standard temperature and pressure is 25.degree.
C. and 1 atmosphere. Unless stated otherwise, generally, the term
"about" is meant to encompass a variance or range of .+-.10%, the
experimental or instrument error associated with obtaining the
stated value, and preferably the larger of these.
[0063] A. Biochars
[0064] Typically, biochars include porous carbonaceous materials,
such as charcoal, that are used as soil amendments or other
suitable applications. Biochar most commonly is created by
pyrolysis of a biomass. In addition to the benefits to plant
growth, yield and quality, etc.; biochar provides the benefit of
reducing carbon dioxide (CO.sub.2) in the atmosphere by serving as
a method of carbon sequestration. Thus, biochar has the potential
to help mitigate climate change, via carbon sequestration. However,
to accomplish this important, yet ancillary benefit, to any
meaningful extent, the use of biochar in agricultural applications
must become widely accepted, e.g., ubiquitous. Unfortunately,
because of the prior failings in the biochar arts, this has not
occurred. It is believed that with the solutions of the present
invention may this level of use of biochar be achieved; and more
importantly, yet heretofore unobtainable, realize the benefit of
significant carbon dioxide sequestration.
[0065] In general, one advantage of putting biochar in soil
includes long term carbon sequestration. It is theorized that as
worldwide carbon dioxide emissions continue to mount, benefits may
be obtained by, controlling, mitigating and reducing the amount of
carbon dioxide in the atmosphere and the oceans. It is further
theorized that increased carbon dioxide emissions are associated
with the increasing industrial development of developing nations,
and are also associated with the increase in the world's
population. In addition to requiring more energy, the increasing
world population will require more food. Thus, rising carbon
dioxide emissions can be viewed as linked to the increasing use of
natural resources by an ever increasing global population. As some
suggest, this larger population brings with it further demands on
food production requirements. Biochar uniquely addresses both of
these issues by providing an effective carbon sink, e.g., carbon
sequestration agent, as well as, an agent for improving and
increasing agricultural output. In particular, biochar is unique in
its ability to increase agricultural production, without increasing
carbon dioxide emission, and preferably reducing the amount of
carbon dioxide in the atmosphere. However, as discussed above, this
unique ability of biochar has not been realized, or seen, because
of the inherent problems and failings of prior biochars including,
for example, high pH, phytotoxicity due to high metals content
and/or residual organics, and dramatic product inconsistencies.
[0066] Biochar can be made from basically any source of carbon, for
example, from hydrocarbons (e.g., petroleum based materials, coal,
lignite, peat) and from a biomass (e.g., woods, hardwoods,
softwoods, waste paper, coconut shell, manure, chaff, food waste,
etc.). Combinations and variations of these starting materials, and
various and different members of each group of starting materials
can be, and are, used. Thus, the large number of vastly different
starting materials leads to biochars having different
properties.
[0067] Many different pyrolysis or carbonization processes can be,
and are used, to create biochars. In general, these processes
involve heating the starting material under positive pressure,
reduced pressure, vacuum, inert atmosphere, or flowing inert
atmosphere, through one or more heating cycles where the
temperature of the material is generally brought above about
400.degree. C., and can range from about 300.degree. C. to about
900.degree. C. The percentage of residual carbon formed and several
other initial properties are strong functions of the temperature
and time history of the heating cycles. In general, the faster the
heating rate and the higher the final temperature the lower the
char yield. Conversely, in general, the slower the heating rate or
the lower the final temperature the greater the char yield. The
higher final temperatures also lead to modifying the char
properties by changing the inorganic mineral matter compositions,
which in turn, modify the char properties. Ramp, or heating rates,
hold times, cooling profiles, pressures, flow rates, and type of
atmosphere can all be controlled, and typically are different from
one biochar supplier to the next. These differences potentially
lead to a biochar having different properties, further framing the
substantial nature of one of the problems that the present
inventions address and solve. Generally, in carbonization most of
the non-carbon elements, hydrogen and oxygen are first removed in
gaseous form by the pyrolytic decomposition of the starting
materials, e.g., the biomass. The free carbon atoms group or
arrange into crystallographic formations known as elementary
graphite crystallites. Typically, at this point the mutual
arrangement of the crystallite is irregular, so that free
interstices exist between them. Thus, pyrolysis involves thermal
decomposition of carbonaceous material, e.g., the biomass,
eliminating non-carbon species, and producing a fixed carbon
structure.
[0068] As noted above, raw or untreated biochar is generally
produced by subjecting biomass to either a uniform or varying
pyrolysis temperature (e.g., 300.degree. C. to 550.degree. C. to
750.degree. C. or more) for a prescribed period of time in a
reduced oxygen environment. This process may either occur quickly,
with high reactor temperature and short residence times, slowly
with lower reactor temperatures and longer residence times, or
anywhere in between. To achieve better results, the biomass from
which the char is obtained may be first stripped of debris, such as
bark, leaves and small branches, although this is not necessary.
The biomass may further include feedstock to help adjust the pH and
particle size distribution in the resulting raw biochar. In some
applications, it is desirous to have biomass that is fresh, less
than six months old, and with an ash content of less than 3%.
Further, by using biochar derived from different biomass, e.g.,
pine, oak, hickory, birch and coconut shells from different
regions, and understanding the starting properties of the raw
biochar, the treatment methods can be tailored to ultimately yield
a treated biochar with predetermined, predictable physical and
chemical properties.
[0069] In general, biochar particles can have a very wide variety
of particle sizes and distributions, usually reflecting the sizes
occurring in the input biomass. Additionally, biochar can be ground
or crushed after pyrolysis to further modify the particle sizes.
Typically, for agricultural uses, biochars with consistent,
predictable particle sizes are more desirable. By way of example,
the biochar particles can have particle sizes as shown or measured
in Table 1 below. When referring to a batch having 1/4 inch
particles, the batch would have particles that will pass through a
3 mesh sieve, but will not pass through (i.e., are caught by or sit
atop) a 4 mesh sieve.
TABLE-US-00001 TABLE 1 U.S. Mesh Microns Millimeters (i.e., mesh)
Inches (.mu.m) (mm) 3 0.2650 6730 6.370 4 0.1870 4760 4.760 5
0.1570 4000 4.000 6 0.1320 3360 3.360 7 0.1110 2830 2.830 8 0.0937
2380 2.380 10 0.0787 2000 2.000 12 0.0661 1680 1.680 14 0.0555 1410
1.410 16 0.0469 1190 1.190 18 0.0394 1000 1.000 20 0.0331 841 0.841
25 0.0280 707 0.707 30 0.0232 595 0.595 35 0.0197 500 0.500 40
0.0165 400 0.400 45 0.0138 354 0.354 50 0.0117 297 0.297 60 0.0098
250 0.250 70 0.0083 210 0.210 80 0.0070 177 0.177 100 0.0059 149
0.149 120 0.0049 125 0.125 140 0.0041 105 0.105 170 0.0035 88 0.088
200 0.0029 74 0.074 230 0.0024 63 0.063 270 0.0021 53 0.053 325
0.0017 44 0.044 400 0.0015 37 0.037
[0070] For most applications, it is desirable to use biochar
particles having particle sizes from about 3/4 mesh to about 60/70
mesh, about 4/5 mesh to about 20/25 mesh, or about 4/5 mesh to
about 30/35 mesh. It being understood that the desired mesh size,
and mesh size distribution can vary depending upon a particular
application for which the biochar is intended.
[0071] FIG. 1 illustrates a cross-section of one example of a raw
biochar particle. As illustrated in FIG. 1, a biochar particle 100
is a porous structure that has an outer surface 100a and a pore
structure 101 formed within the biochar particle 100. As used
herein, unless specified otherwise, the terms "porosity", "porous",
"porous structure", and "porous morphology" and similar such terms
are to be given their broadest possible meaning, and would include
materials having open pores, closed pores, and combinations of open
and closed pores, and would also include macropores, mesopores, and
micropores and combinations, variations and continuums of these
morphologies. Unless specified otherwise, the term "pore volume" is
the total volume occupied by the pores in a particle or collection
of particles; the term "inter-particle void volume" is the volume
that exists between a collection of particle; the term "solid
volume or volume of solid means" is the volume occupied by the
solid material and does not include any free volume that may be
associated with the pore or inter-particle void volumes; and the
term "bulk volume" is the apparent volume of the material including
the particle volume, the inter-particle void volume, and the
internal pore volume.
[0072] The pore structure 101 forms an opening 121 in the outer
surface 100a of the biochar particle 100. The pore structure 101
has a macropore 102, which has a macropore surface 102a, and which
surface 102a has an area, i.e., the macropore surface area. (In
this diagram only a single micropore is shown. If multiple
micropores are present than the sum of their surface areas would
equal the total macropore surface area for the biochar particle.)
From the macropore 102, several mesopores 105, 106, 107, 108 and
109 are present, each having its respective surfaces 105a, 106a,
107a, 108a and 109a. Thus, each mesopore has its respective surface
area; and the sum of all mesopore surface areas would be the total
mesopore surface area for the particle. From the mesopores, e.g.,
107, there are several micropores 110, 111, 112, 113, 114, 115,
116, 117, 118, 119 and 120, each having its respective surfaces
110a, 111a, 112a, 113a, 114a, 115a, 116a, 117a, 118a, 119a and
120a. Thus, each micropore has its respective surface area and the
sum of all micropore surface areas would be the total micropore
surface area for the particle. The sum of the macropore surface
area, the mesopore surface area and the micropore surface area
would be the total pore surface area for the particle.
[0073] Macropores are typically defined as pores having a diameter
greater than 300 nm, mesopores are typically defined as diameter
from about 1-300 nm, and micropores are typically defined as
diameter of less than about 1 nm, and combinations, variations and
continuums of these morphologies. The macropores each have a
macropore volume, and the sum of these volumes would be the total
macropore volume. The mesopores each have a mesopore volume, and
the sum of these volumes would be the total mesopore volume. The
micropores each have a micropore volume, and the sum of these
volumes would be the total micropore volume. The sum of the
macropore volume, the mesopore volume and the micropore volume
would be the total pore volume for the particle.
[0074] Additionally, the total pore surface area, volume, mesopore
volume, etc., for a batch of biochar would be the actual,
estimated, and preferably calculated sum of all of the individual
properties for each biochar particle in the batch.
[0075] It should be understood that the pore morphology in a
biochar particle may have several of the pore structures shown, it
may have mesopores opening to the particle surface, it may have
micropores opening to particle surface, it may have micropores
opening to macropore surfaces, or other combinations or variations
of interrelationship and structure between the pores. It should
further be understood that the pore morphology may be a continuum,
where moving inwardly along the pore from the surface of the
particle, the pore transitions, e.g., its diameter becomes smaller,
from a macropore, to a mesopore, to a micropore, e.g., macropore
102 to mesopore 109 to micropore 114.
[0076] In general, the biochars have porosities that can range from
0.2 cm.sup.3/cm.sup.3 to about 0.8 cm.sup.3/cm.sup.3 and more
preferably about 0.2 cm.sup.3/cm.sup.3 to about 0.5
cm.sup.3/cm.sup.3. (Unless stated otherwise, porosity is provided
as the ratio of the total pore volumes (the sum of the
micro+meso+macro pore volumes) to the solid volume of the biochar.
Porosity of the biochar particles can be determined, or measured,
by measuring the micro-, meso-, and macro pore volumes, the bulk
volume, and the inter particle volumes to determine the solid
volume by difference. The porosity is then calculated from the
total pore volume and the solid volume.
[0077] As noted above, the use of different biomass potentially
leads to biochars having different properties, including, but not
limited to different pore structures. By way of example, FIGS. 2A,
2B and 2C illustrate Scanning Electron Microscope ("SEM") images of
various types of treated biochars showing the different nature of
their pore morphology. FIG. 2A is biochar derived from pine. FIG.
2B is biochar derived from birch. FIG. 2C is biochar derived from
coconut shells.
[0078] The surface area and pore volume for each type of pore,
e.g., macro-, meso- and micro can be determined by direct
measurement using CO.sub.2 adsorption for micro-, N.sub.2
adsorption for meso- and macro pores and standard analytical
surface area analyzers and methods, for example, particle analyzers
such as Micrometrics instruments for meso- and micro pores and
impregnation capacity for macro pore volume. Mercury porosimetry,
which measures the macroporosity by applying pressure to a sample
immersed in mercury at a pressure calibrated for the minimum pore
diameter to be measured, may also be used to measure pore
volume.
[0079] The total micropore volume can be from about 2% to about 25%
of the total pore volume. The total mesopore volume can be from
about 4% to about 35% of the total pore volume. The total macropore
volume can be from about 40% to about 95% of the total pore volume.
By way of example, FIG. 3 shows a bar chart setting out examples of
the pore volumes for sample biochars made from peach pits 201,
juniper wood 202, a first hard wood 203, a second hard wood 204,
fir and pine waste wood 205, a first pine 206, a second pine 207,
birch 208 and coconut shells 209.
[0080] As explained further below, treatment can increase usable
pore volumes and, among other things, remove obstructions in the
pores, which leads to increased retention properties and promotes
further performance characteristics of the biochar. Knowing the
properties of the starting raw biochar, one can treat the biochar
to produce controlled, predictable and optimal resulting physical
and chemical properties.
[0081] B. Treatment
[0082] The rationale for treating the biochar after pyrolysis is
that given the large pore volume and large surface are of the
biochars, it is most efficient to make significant changes in the
physical and chemical properties of the biochar by treating both
the internal and external surfaces and internal pore volume of the
char. Testing has demonstrated that if the biochar is treated, at
least partially, in a manner that causes the forced infusion and/or
diffusion of liquids into and/or out of the biochar pores (through
mechanical, physical, or chemical means), certain properties of the
biochar can be altered or improved over and above simply contacting
these liquids with the biochar. By knowing the properties of the
raw biochar and the optimal desired properties of the treated
biochar, the raw biochar can then be treated in a manner that
results in the treated biochar having controlled optimized
properties.
[0083] For purposes of this application, treating and/or washing
the biochar in accordance with the present invention involves more
than a simple wash or soak, which generally only impacts the
exterior surfaces and a small percentage of the interior surface
area. "Washing" or "treating" in accordance with the present
invention, and as used below, involves treatment of the biochar in
a manner that causes the forced, accelerated or assisted infusion
and/or diffusion of liquids and/or additivities into and/or out of
the biochar pores (through mechanical, physical, or chemical means)
such that certain properties of the biochar can be altered or
improved over and above simply contacting these liquids with the
biochar or so that treatment becomes more efficient or rapid from a
time standpoint over simple contact or immersion.
[0084] In particular, effective treatment processes can mitigate
deleterious pore surface properties, remove undesirable substances
from pore surfaces or volume, and impact anywhere from between 10%
to 99% or more of pore surface area of a biochar particle. By
modifying the usable pore surfaces through treatment and removing
deleterious substances from the pore volume, the treated biochars
can exhibit a greater capacity to retain water and/or other
nutrients as well as being more suitable habitats for some forms of
microbial life. Through the use of treated biochars, agricultural
applications can realize increased moisture control, increased
nutrient retention, reduced water usage, reduced water
requirements, reduced runoff or leaching, increased nutrient
efficiency, reduced nutrient usage, increased yields, increased
yields with lower water requirements and/or nutrient requirements,
increases in beneficial microbial life, improved performance and/or
shelf life for inoculated bacteria, and any combination and
variation of these and other benefits.
[0085] Treatment further allows the biochar to be modified to
possess certain known properties that enhance the benefits received
from the use of biochar. While the selection of feedstock, raw
biochar and/or pyrolysis conditions under which the biochar was
manufactured can make treatment processes less cumbersome, more
efficient and further controlled, treatment processes can be
utilized that provide for the biochar to have desired and generally
sustainable resulting properties regardless of the biochar source
or pyrolysis conditions. As explained further below, treatment can
(i) repurpose problematic biochars, (ii) handle changing biochar
material sources, e.g., seasonal and regional changes in the source
of biomass, (iii) provide for custom features and functions of
biochar for particular soils, regions or agricultural purposes;
(iv) increase the retention properties of biochar, (v) provide for
large volumes of biochar having desired and predictable properties,
(vi) provide for biochar having custom properties, (vii) handle
differences in biochar caused by variations in pyrolysis conditions
or manufacturing of the "raw" biochar; and (viii) address the
majority, if not all, of the problems that have, prior to the
present invention, stifled the large scale adoption and use of
biochars.
[0086] Treatment can wash both the interior and exterior pore
surfaces, remove harmful chemicals, introduce beneficial
substances, and alter certain properties of the biochar and the
pore surfaces and volumes. This is in stark contrast to simple
washing which generally only impacts the exterior surfaces and a
small percentage of the interior surface area. Treatment can
further be used to coat substantially all of the biochar pore
surfaces with a surface modifying agent or impregnate the pore
volume with additives or treatment to provide a predetermined
feature to the biochar, e.g., surface charge and charge density,
surface species and distribution, targeted nutrient addition,
magnetic modifications, root growth facilitator, and water
absorptivity and water retention properties. Just as importantly,
treatment can also be used to remove undesirable substances from
the biochar, such as dioxins or other toxins either through
physical removal or through chemical reactions causing
neutralization.
[0087] FIG. 4 is a schematic flow diagram of one example treatment
process 400 for use in accordance with the present invention. As
illustrated, the treatment process 400 starts with raw biochar 402
that may be subjected to one or more reactors or treatment
processes prior to bagging 420 the treated biochar for resale. For
example, 404 represents reactor 1, which may be used to treat the
biochar. The treatment may be a simple water wash or may be an acid
wash used for the purpose of altering the pH of the raw biochar
particles 402. The treatment may also contain a surfactant or
detergent to aid the penetration of the treatment solution into the
pores of the biochar. The treatment may optionally be heated,
cooled, or may be used at ambient temperature or any combination of
the three. For some applications, depending upon the properties of
the raw biochar, a water and/or acid/alkaline wash 404 (the latter
for pH adjustment) may be the only necessary treatment prior to
bagging the biochar 420. If, however, the moisture content of the
biochar needs to be adjusted, the treated biochar may then be put
into a second reactor 406 for purposes of reducing the moisture
content in the washed biochar. From there, the treated and moisture
adjusted biochar may be bagged 420.
[0088] Again, depending upon the starting characteristics of the
raw biochar and the intended application for the resale product,
further processing may still be needed or desired. In this case,
the treated moisture adjusted biochar may then be passed to a third
reactor 408 for inoculation, which may include the impregnation of
biochar with beneficial additives, such as nutrients, bacteria,
microbes, fertilizers or other additives. Thereafter, the
inoculated biochar may be bagged 420, or may be yet further
processed, for example, in a fourth reactor 410 to have further
moisture removed from or added to the biochar. Further moisture
adjustment may be accomplished by placing the inoculated biochar in
a fourth moisture adjustment reactor 410 or circulating the biochar
back to a previous moisture adjustment reactor (e.g. reactor 406).
Those skilled in the art will recognize that the ordering in which
the raw biochar is processed and certain processes may be left out,
depending on the properties of the starting raw biochar and the
desired application for the biochar. For example, the treatment and
inoculation processes may be performed without the moisture
adjustment step, inoculation processes may also be performed with
or without any treatment, pH adjustment or any moisture adjustment.
All the processes may be completed alone or in the conjunction with
one or more of the others.
[0089] For example, FIG. 4a illustrates a schematic of one example
of an implementation of biochar processing that includes washing
the pores and both pH and moisture adjustment. FIG. 4b illustrates
yet another example of an implementation of biochar processing that
includes inoculation.
[0090] As illustrated in FIG. 4a, raw biochar 402 is placed into a
reactor or tank 404. A washing or treatment liquid 403 is then
added to a tank and a partial vacuum, using a vacuum pump, 405 is
pulled on the tank. The treating or washing liquid 403 may be used
to clean or wash the pores of the biochar 402 or adjust the
chemical or physical properties of the surface area or pore volume,
such as pH level, usable pore volume, or VOC content, among other
things. The vacuum can be applied after the treatment liquid 403 is
added or while the treatment liquid 403 is added. Thereafter, the
washed/adjusted biochar 410 may be moisture adjusted by vacuum
exfiltration 406 to pull the extra liquid from the washed/moisture
adjusted biochar 410 or may be placed in a centrifuge 407, heated
or subjected to pressure gradient changes (e.g., blowing air) for
moisture adjustment. The moisture adjusted biochar 412 may then be
bagged or subject to further treatment. Any excess liquids 415
collected from the moisture adjustment step may be disposed of or
recycled, as desired. Optionally, biochar fines may be collected
from the excess liquids 415 for further processing, for example, to
create a slurry, cakes, or biochar extrudates.
[0091] Optionally, rather than using a vacuum pump 405, a positive
pressure pump may be used to apply positive pressure to the tank
404. In some situations, applying positive pressure to the tank may
also function to force or accelerate the washing or treating liquid
403 into the pores of the biochar 402. Any change in pressure in
the tank 404 or across the surface of the biochar could facilitate
the exchange of gas and/or moisture into and out of the pores of
the biochar with the washing or treating liquid 403 in the tank.
Accordingly, changing the pressure in the tank and across the
surface of the biochar, whether positive or negative, is within the
scope of this invention.
[0092] As illustrated FIG. 4b, the washed/adjusted biochar 410 or
the washed/adjusted and moisture adjusted biochar 412 may be
further treated by inoculating or impregnating the pores of the
biochar with an additive 425. The biochar 410, 412 placed back in a
reactor 401, an additive solution 425 is placed in the reactor 401
and a vacuum, using a vacuum pump, 405 is applied on the tank.
Again, the vacuum can be applied after the additive solution 425 is
added to the tank or while the additive solution 425 is being added
to the tank. Thereafter, the washed, adjusted and inoculated
biochar 428 can be bagged. Alternatively, if further moisture
adjustment is required, the biochar can be further moisture
adjusted by vacuum filtration 406 to pull the extra liquid from the
washed/moisture adjusted biochar 410 or may be placed in a
centrifuge 407 for moisture adjustment. The resulting biochar 430
can then be bagged. Any excess liquids 415 collected from the
moisture adjustment step may be disposed of or recycled, as
desired. Optionally, biochar particulates or "fines" which easily
are suspended in liquid may be collected from the excess liquids
415 for further processing, for example, to create a slurry,
biochar extrudates, or merely a biochar product of a consistently
smaller particle size. As described above, both processes of the
FIGS. 4a and 4b can be performed with a surfactant solution in
place of, or in conjunction with, the vacuum 405.
[0093] While known processes exist for the above described
processes, research associated with the present invention has shown
improvement and the ability to better control the properties and
characteristics of the biochar if the processes are performed
through the infusion and diffusion of liquids into and out of the
biochar pores. One such treatment process that can be used is
vacuum impregnation and vacuum and/or centrifuge extraction.
Another such treatment process that can be used is the addition of
a surfactant to infused liquid, which infused liquid may be
optionally heated, cooled, or used at ambient temperature or any
combination of the three.
[0094] Since research associated with the present invention has
identified what physical and chemical properties have the highest
impact on plant growth and/or soil health, the treatment process
can be geared to treat different forms of raw biochar to achieve
treated biochar properties known to enhance these characteristics.
For example, if the pH of the biochar needs to be adjusted to
enhance the raw biochar performance properties, the treatment may
be the infusion of an acid solution into the pores of the biochar
using vacuum, surfactant, or other treatment means. This treatment
of pore infusion through, for example, the rapid, forced infusion
of liquid into and out the pores of the biochar, has further been
proven to sustain the adjusted pH levels of the treated biochar for
much longer periods than biochar that is simply immersed in an acid
solution for the same period of time. By way of another example, if
the moisture content needs to be adjusted, then excess liquid and
other selected substances (e.g. chlorides, dioxins, and other
chemicals, to include those previously deposited by treatment to
catalyze or otherwise react with substances on the interior or
exterior surfaces of the biochar) can be extracted from the pores
using vacuum and/or centrifuge extraction or by using various
heating techniques. The above describes a few examples of treatment
that result in treated biochar having desired performance
properties identified to enhance soil health and plant life.
[0095] FIG. 5 illustrates one example of a system 500 that utilizes
vacuum impregnation to treat raw biochar. Generally, raw biochar
particles, and preferably a batch of biochar particles, are placed
in a reactor, which is connected to a vacuum pump, and a source of
treating liquid (i.e. water or acidic/basis solution). When the
valve to the reactor is closed, the pressure in the reactor is
reduced to values ranging from 750 Torr to 400 Torr to 10 Torr or
less. The biochar is maintained under vacuum ("vacuum hold time")
for anywhere from seconds to 1 minute to 10 minutes, to 100
minutes, or possibly longer. By way of example, for about a 500
pound batch of untreated biochar, a vacuum hold time of from about
1 to about 5 minutes can be used if the reactor is of sufficient
size and sufficient infiltrate is available to adjust the necessary
properties. While under the vacuum the treating liquid may then be
introduced into the vacuum chamber containing the biochar.
Alternatively, the treating liquid may be introduced into the
vacuum chamber before the biochar is placed under a vacuum.
Optionally, treatment may also include subjecting the biochar to
elevated temperatures from ambient to about 250.degree. C. or
reduced temperatures to about -25.degree. C. or below, with the
limiting factor being the temperature and time at which the
infiltrate can remain flowable as a liquid or semi-liquid.
[0096] The infiltrate or treating liquid is drawn into the biochar
pore, and preferably drawn into the macropores and mesopores.
Depending upon the specific doses applied and pore structure of the
biochar, the infiltrate can coat anywhere from 10% to 50% to 100%
of the total macropore and mesopore surface area and can fill or
coat anywhere from a portion to nearly all (10%-100%) of the total
macropore and mesopore volume.
[0097] As described above, the treating liquid can be left in the
biochar, with the batch being a treated biochar batch ready for
packaging, shipment and use in an agricultural or other
application. The treating liquid may also be removed through
drying, subsequent vacuum processing, centrifugal force (e.g.,
cyclone drying machines or centrifuges), with the batch being a
treated biochar batch ready for packaging, shipment and use in an
agricultural application. A second, third or more infiltration,
removal, infiltration and removal, and combinations and variations
of these may also be performed on the biochar with optional drying
steps between infiltrations to remove residual liquid from and
reintroduce gasses to the pore structure if needed. In any of these
stages the liquid may contain organic or inorganic surfactants to
assist with the penetration of the treating liquid.
[0098] As illustrated in FIG. 5, a system 500 for providing a
biochar, preferably having predetermined and uniform properties.
The system 500 has a vacuum infiltration tank 501. The vacuum
infiltration tank 501 has an inlet line 503 that has a valve 504
that seals the inlet line 503. In operation, the starting biochar
is added to vacuum infiltration tank 501 as shown by arrow 540.
Once the tank is filled with the starting biochar, a vacuum is
pulled on the tank, by a vacuum pump connected to vacuum line 506,
which also has valve 507. The starting biochar is held in the
vacuum for a vacuum hold time. Infiltrate, as shown by arrow 548 is
added to the tank 501 by line 508 having valve 509. The infiltrate
is mixed with the biochar in the tank 501 by agitator 502. The
mixing process is done under vacuum for a period of time sufficient
to have the infiltrate fill the desired amount of pore volume,
e.g., up to 100% of the macropores and mesopores.
[0099] Alternatively, the infiltrate may be added to the vacuum
infiltration tank 501 before vacuum is pulled on the tank. In this
manner, infiltrate is added in the tank in an amount that can be
impregnated into the biochar. As the vacuum is pulled, the biochar
is circulated in the tank to cause the infiltrate to fill the pore
volume. To one skilled in the art, it should be clear that the
agitation of the biochar during this process can be performed
through various means, such as a rotating tank, rotating agitator,
pressure variation in the tank itself, or other means.
Additionally, the biochar may be dried using conventional means
before even the first treatment. This optional pre-drying can
remove liquid from the pores and in some situations may increase
the efficiency of impregnation due to pressure changes in the
tank.
[0100] Pressure is then restored in the tank 501 and the
infiltrated biochar is removed, as shown by arrow 541, from the
tank 501 to bin 512, by way of a sealing gate 511 and removal line
510. The infiltrated biochar is collected in bin 512, where it can
be further processed in several different ways. The infiltrated
biochar can be shipped for use as a treated biochar as shown by
arrow 543. The infiltrated biochar can be returned to the tank 501
(or a second infiltration tank). If returned to the tank 501 the
biochar can be processed with a second infiltration step, a vacuum
drying step, a washing step, or combinations and variations of
these. The infiltrated biochar can be moved by conveyor 514, as
shown by arrow 542, to a drying apparatus 516, e.g., a centrifugal
dryer or heater, where water, infiltrate or other liquid is removed
by way of line 517, and the dried biochar leaves the dryer through
discharge line 518 as shown by arrow 545, and is collected in bin
519. The biochar is removed from the bin by discharge 520. The
biochar may be shipped as a treated biochar for use in an
agriculture application, as shown by arrow 547. The biochar may
also be further processed, as shown by 546. Thus, the biochar could
be returned to tank 501 (or a second vacuum infiltration tank) for
a further infiltration step. The drying step may be repeated either
by returning the dry biochar to the drying apparatus 516, or by
running the biochar through a series of drying apparatus, until the
predetermined dryness of the biochar is obtained, e.g., between 50%
to less than 1% moisture.
[0101] The system 500 is illustrative of the system, equipment and
processes that can be used for, and to carry out the present
inventions. Various other implementations and types of equipment
can be used. The vacuum infiltration tank can be a sealable
off-axis rotating vessel, chamber or tank. It can have an internal
agitator that also when reversed can move material out, empty it,
(e.g., a vessel along the lines of a large cement truck, or ready
mix truck, that can mix and move material out of the tank, without
requiring the tank's orientation to be changed). Washing equipment
may be added or utilized at various points in the process, or may
be carried out in the vacuum tank, or drier, (e.g., wash fluid
added to biochar as it is placed into the drier for removal). Other
steps, such as bagging, weighing, the mixing of the biochar with
other materials, e.g., fertilized, peat, soil, etc. can be carried
out. In all areas of the system referring to vacuum infiltration,
optionally positive pressure can be applied, if needed, to enhance
the penetration of the infiltrate or to assist with re-infusion of
gaseous vapors into the treated char. Additionally, where feasible,
especially in positive pressure environments, the infiltrate may
have soluble gasses added which then can assist with removal of
liquid from the pores, or gaseous treatment of the pores upon
equalization of pressure.
[0102] As noted above, the biochar may also be treated using a
surfactant. The same or similar equipment used in the vacuum
infiltration process can be used in the surfactant treatment
process. Although it is not necessary to apply a vacuum in the
surfactant treatment process, the vacuum infiltration tank or any
other rotating vessel, chamber or tank can be used. In the
surfactant treatment process, a surfactant, such as yucca extract,
is added to the infiltrate, e.g., acid wash or water. The quantity
of the surfactant added to the infiltrate may vary depending upon
the surfactant used. For example, organic yucca extract can be
added at a rate of between 0.1-20%, but more preferably 1-5% by
volume of the infiltrate. The infiltrate with surfactant is then
mixed with the biochar in a tumbler for several minutes, e.g., 3-5
minutes, without applied vacuum. Optionally, a vacuum or positive
pressure may be applied with the surfactant to improve efficiency,
but is not necessary. Additionally, infiltrate to which the
surfactant or detergent is added may be heated or may be ambient
temperature or less. Similarly, the mixture of the surfactant or
detergent, as well as the char being treated may be heated, or may
be ambient temperature, or less. After tumbling, excess free liquid
can be removed in the same manner as described above in connection
with the vacuum infiltration process. Drying, also as described
above in connection with the vacuum infiltration process, is an
optional additional step. Besides yucca extract, a number of other
surfactants may be used for surfactant treatment, which include,
but are not limited to, the following: nonionic types, such as,
ethoxylated alcohols, phenols-lauryl alcohol ethoxylates, Fatty
acid esters-sorbitan, tween 20, amines, amides-imidazoles; anionic
types, such as sulfonates-arylalkyl sulfonates and sulfate-sodium
dodecyl sulfate; cationic types, such as alkyl-amines or
ammoniums-quaternary ammoniums; and amphoteric types, such as
betaines-cocamidopropyl betaine.
[0103] Optionally, the biochar may also be treated by applying
ultrasonics. In this treatment process, the biochar may be
contacted with a treating liquid that is agitated by ultrasonic
waves. By agitating the treating liquid, contaminants may be
dislodged or removed from the biochar due to bulk motion of the
fluid in and around the biocarbon, pressure changes, including
cavitation in and around contaminants on the surface, as well as
pressure changes in or near pore openings (cavitation bubbles) and
internal pore cavitation.
[0104] In this manner, agitation will cause contaminants of many
forms to be released from the internal and external structure of
the biochar. The agitation also encourages the exchange of water,
gas, and other liquids with the internal biochar structure.
Contaminants are transported from the internal structure to the
bulk liquid (treating fluid) resulting in biochar with improved
physical and chemical properties. The effectiveness of ultrasonic
cleaning is tunable as bubble size and number is a function of
frequency and power delivered by the transducer to the treating
fluid
[0105] In one example, applying ultrasonic treatment, raw wood
based biochar between 10 microns to 10 mm with moisture content
from 0% to 90% may be mixed with a dilute mixture of acetic acid
and water (together the treating liquid) in a processing vessel
that also translates the slurry (the biochar/treating liquid
mixture). During translation, the slurry passes near an ultrasonic
transducer to enhance the interaction between the fluid and
biochar. The biochar may experience one or multiple washes of
dilute acetic acid, water, or other treating fluids. The biochar
may also make multiple passes by ultrasonic transducers to enhance
physical and chemical properties of the biochar. For example, once
a large volume of slurry is made, it can continuously pass an
ultrasonic device and be degassed and wetted to its maximum, at a
rapid processing rate. The slurry can also undergo a separation
process in which the fluid and solid biochar are separated at 60%
effectiveness or greater.
[0106] Through ultrasonic treatment, the pH of the biochar, or
other physical and chemical properties may be adjusted and the
mesopore and macropore surfaces of the biochar may be cleaned and
enhanced. Further, ultrasonic treatment can be used in combination
with bulk mixing with water, solvents, additives (fertilizers,
etc.), and other liquid based chemicals to enhance the properties
of the biochar. After treatment, the biochar may be subject to
moisture adjustment, further treatment and/or inoculation using any
of the methods set forth above.
[0107] C. Benefits of Treatment
[0108] As illustrated above, the treatment process, whether using
vacuum, surfactant or ultrasonic treatment, or a combination
thereof, may include two steps, which in certain applications, may
be combined: (i) washing and (ii) inoculation of the pores with an
additive. When the desired additive is the same and that being
inoculated into the pores, e.g., water, the step of washing the
pores and inoculating the pores with an additive may be
combined.
[0109] While not exclusive, washing is generally done for one of
three purposes: (i) to modify the surface of the pore structure of
the biochar (i.e., to allow for increased retention of liquids);
(ii) to modify the pH of the biochar; and/or (iii) to remove
undesired and potentially harmful compounds or gases.
[0110] 1. Increases Water Holding Capacity/Water Retention
Capacity
[0111] As demonstrated below, the treatment processes of the
invention modify the surfaces of the pore structure to provide
enhanced functionality and to control the properties of the biochar
to achieve consistent and predicable performance. Using the above
treatment processes, anywhere from at least 10% of the total pore
surface area up to 90% or more of the total pore surface area may
be modified. In some implementations, it may be possible to achieve
modification of up to 99% or more of the total pore surface area of
the biochar particle. Using the processes set forth above, such
modification may be substantially and uniformly achieved for an
entire batch of treated biochar.
[0112] For example, it is believed that by treating the biochar as
set forth above, the hydrophilicity of the surface of the pores of
the biochar is modified, allowing for a greater water retention
capacity. Further, by treating the biochars as set forth above,
gases and other substances are also removed from the pores of the
biochar particles, also contributing to the biochar particles'
increased water holding capacity. Thus, the ability of the biochar
to retain liquids, whether water or additives in solution, is
increased, which also increases the ability to load the biochar
particles with large volumes of inoculant, infiltrates and/or
additives.
[0113] A batch of biochar has a bulk density, which is defined as
weight in grams (g) per cm.sup.3 of loosely poured material that
has or retains some free space between the particles. The biochar
particles in this batch will also have a solid density, which is
the weight in grams (g) per cm.sup.3 of just particles, i.e., with
the free space between the particles removed. The solid density
includes the air space or free space that is contained within the
pores, but not the free space between particles. The actual density
of the particles is the density of the material in grams (g) per
cm.sup.3 of material, which makes up the biochar particles, i.e.,
the solid material with pore volume removed.
[0114] In general, as bulk density increases the pore volume is
expected to decrease. When the pore volume is macro or mesoporous,
the ability of the material to hold infiltrate, e.g., inoculant is
directly proportional to the pore volume, thus it is also expected
to decrease as bulk density increases. With the infiltration
processes, the treated biochars can have impregnation capacities
that are larger than could be obtained without infiltration, e.g.,
the treated biochars can readily have 30%, 40%, 50%, or most
preferably, 60%-100% of their total pore volume filled with an
infiltrate, e.g., an inoculant. The impregnation capacity is the
amount of a liquid that a biochar particle, or batch of particles,
can absorb. The ability to make the pores surface hydrophilic, and
to infuse liquid deep into the pore structure through the
application of positive or negative pressure and/or a surfactant,
alone or in combination, provides the ability to obtain these high
impregnation capabilities. The treated biochars can have
impregnation capacities, i.e., the amount of infiltrate that a
particle can hold on a volume held/total volume of a particle
basis, that is greater than 0.2 cm.sup.3/cm.sup.3 to 0.8
cm.sup.3/cm.sup.3. Resulting bulk densities of treated biochar can
range from 0.1-0.6 g/cm.sup.3 and sometimes preferably between
0.3-0.6 g/cm.sup.3 and can have solid densities ranging from
0.2-1.2 g/cm.sup.3.
[0115] Accordingly, by using the treatment above, the water
retention capacity of biochar can be greatly increased over the
water retention capacities of various soil types and even raw
biochar, thereby holding water and/or nutrients in the plant's root
zone longer and ultimately reducing the amount of applied water
(through irrigation, rainfall, or other means) needed by up to 50%
or more. FIG. 6 is a chart showing the water retention capacities
of soils versus raw and treated biochar. The soils sampled are loam
and sandy clay soil and a common commercial horticultural mix. The
charts show the retained water as a function of time.
[0116] In chart A, the bottom line represents the retained water in
the sandy claim loam soil over time. The middle line represents the
retained water in the sandy clay soil with 20% by volume percent of
unprocessed raw biochar. The top line represents the retained water
in the sandy clay loam soil with 20% by volume percent of treated
biochar (adjusted and inoculated biochar). Chart B represents the
same using a soilless potting mix rather than sandy clay loam
soil.
[0117] As illustrated in FIG. 7, testing showed a treated biochar
had an increased water retention capacity of approximately 1.5
times that of the raw biochar from the same feedstock. Similar
results have been seen with biochars derived from various
feedstocks. With certain biochar types, the water retention
capacity of treated biochar could be as great as three times that
of raw biochar.
[0118] "Water holding capacity," which may also be referred to as
"Water Retention Capacity," is the amount of water that can be held
both internally within the porous structure and in the
interparticle void spaces in a given batch of particles. While a
summary of the method of measure is provided above, a more specific
method of measuring water holding capacity/water retention capacity
is measured by the following procedure: (i) drying a sample of
material under temperatures of 105.degree. C. for a period of 24
hours or using another scientifically acceptable technique to
reduce the moisture content of the material to less than 2%, less
than 1%; and preferably less than 0.5% (ii) placing a measured
amount of dry material in a container; (iii) filling the container
having the measured amount of material with water such that the
material is completely immersed in the water; (iv) letting the
water remain in the container having the measured amount of
material for at least ten minutes or treating the material in
accordance with the invention by infusing with water when the
material is a treated biochar; (v) draining the water from the
container until the water ceases to drain; (vi) weighing the
material in the container (i.e., wet weight); (vii) again drying
the material by heating it under temperatures of 105.degree. C. for
a period of 24 hours or using another scientifically acceptable
technique to reduce the moisture content of the material to less
than 2% and preferably less than 1%; and (viii) weighing the dry
material again (i.e., dry weight) and, for purposes of a volumetric
measure, determining the volume of the material.
[0119] Measured gravimetrically, the water holding/water retention
capacity is determined by measuring the difference in weight of the
material from step (vi) to step (viii) over the weight of the
material from step (viii) (i.e., wet weight-dry weight/dry weight).
FIG. 8 illustrates the different water retention capacities of raw
biochar versus treated biochar measured gravimetrically. As
illustrated, water retention capacity of raw biochar can be between
100-200%, whereas treated biochar can have water retention
capacities measured gravimetrically between 200-400%.
[0120] Water holding capacity can also be measured volumetrically
and represented as a percent of the volume of water retained in the
biochar after gravitationally draining the excess water/volume of
biochar The volume of water retained in the biochar after draining
the water can be determined from the difference between the water
added to the container and water drained off the container or from
the difference in the weight of the wet biochar from the weight of
the dry biochar converted to a volumetric measurement. This
percentage water holding capacity for treated biochar may be 50-55
percent and above by volume.
[0121] Given biochar's increased water retention capacity, the
application of the treated biochar and even the raw biochar can
greatly assist with the reduction of water and/or nutrient
application. It has been discovered that these same benefits can be
imparted to agricultural growth.
[0122] Treated biochar of the present invention has also
demonstrated the ability to retain more water than raw biochar
after exposure to the environment for defined periods of time. For
purposes of this application "remaining water content" can be
defined as the total amount of water that remains held by the
biochar after exposure to the environment for certain amount of
time. Exposure to environment is exposure at ambient temperature
and pressures. Under this definition, remaining water content can
be measured by (i) creating a sample of biochar that has reached
its maximum water holding capacity; (ii) determining the total
water content by thermogravimetric analysis (H.sub.2O (TGA)), as
described above on a sample removed from the output of step (i)
above, (iii) exposing the biochar in the remaining sample to the
environment for a period of 2 weeks (15 days, 360 hrs.); (iv)
determining the remaining water content by thermogravimetric
analysis (H.sub.2O (TGA)); and (v) normalizing the remaining
(retained) water in mL to 1 kg or 1 L biochar. The percentage of
water remaining after exposure for this two-week period can be
calculated by the remaining water content of the biochar after the
predetermined period over the water content of the biochar at the
commencement of the two-week period. Using this test, treated
biochar has shown to retain water at rates over 4.times. that of
raw biochar. Testing has further demonstrated that the following
amount of water can remain in treated biochar after two weeks of
exposure to the environment: 100-650 mL/kg; 45-150 mL/L; 12-30
gal/ton; 3-10 gal/yd.sup.3 after 360 hours (15 days) of exposure to
the environment. In this manner, and as illustrated in FIG. 8,
biochar treated with a process consistent with those described in
this disclosure can increase the amount of retained water in
biochar about 3 times compared to other methods even after seven
weeks. In general, the more porous and the higher the surface area
of a given material, the higher the water retention capacity.
Further, it is theorized that by modifying the
hydrophilicity/hydrophobicity of the pore surfaces, greater water
holding capacity and controlled release may be obtained. Thus,
viewed as a weight percent, e.g., the weight of retained water to
weight of biochar, examples of the present biochars can retain more
than 5% of their weight, more than 10% of their weight, and more
than 15% of their weight, and even more than 50% of their weight
compared to an average soil which may retain 2% or less, or between
100-600 ml/kg by weight of biochar.
[0123] Tests have also shown that treated biochars that show weight
loss of >1% in the interval between 43-60.degree. C. when
analyzed by the Thermal Gravimetric Analysis (TGA) (as described
below) demonstrate greater water holding and content capacities
over raw biochars. Weight loss of >5%-15% in the interval
between 38-68.degree. C. when analyzed by the Thermal Gravimetric
Analysis (TGA) using sequences of time and temperature disclosed in
the following paragraphs or others may also be realized. Weight
percentage ranges may vary from between >1%-15% in temperature
ranges between 38-68.degree. C., or subsets thereof, to distinguish
between treated biochar and raw biochar.
[0124] FIG. 9 is a chart 900 showing the weight loss of treated
biochars 902 versus raw biochar samples 904 when heated at varying
temperatures using the TGA testing described below. As illustrated,
the treated biochars 902 continue to exhibit weight loss when
heated between 40-60.degree. C. when analyzed by the Thermal
Gravimetric Analysis (TGA) (described below), whereas the weight
loss in raw biochar 804 between the same temperature ranges levels
off. Thus, testing demonstrates the presence of additional moisture
content in treated biochars 902 versus raw biochars 904.
[0125] In particular, the treated biochars 902 exhibit substantial
water loss when heated in inert gas such as nitrogen following
treatment. More particularly, when heated for 25 minutes at each of
the following temperatures 20, 30, 40, 50 and 60.degree. C. the
treated samples lose about 5-% to 15% in the interval 43-60.degree.
C. and upward of 20-30% in the interval between 38-68.degree. C.
The samples to determine the water content of the raw biochar were
obtained by mixing a measured amount of biochar and water, stirring
the biochar and water for 2 minutes, draining off the water,
measuring moisture content and then subjecting the sample to TGA.
The samples for the treated biochar were obtained by using the same
measured amount of biochar as used in the raw biochar sample and
using treatment process consistent with those described in this
disclosure. The moisture content is then measured and the sample is
subjected to TGA described above.
[0126] The sequences of time and temperature conditions for
evaluating the effect of biochars heating in inert atmosphere is
defined in this application as the "Bontchev-Cheyne Test" ("BCT").
The BCT is run using samples obtained, as described above, and
applying Thermal Gravimetric Analysis (TGA) carried out using a
Hitachi STA 7200 analyzer under nitrogen flow at the rate of 110
mL/min. The biochar samples are heated for 25 minutes at each of
the following temperatures: 20, 30, 40, 50 and 60.degree. C. The
sample weights are measured at the end of each dwell step, at the
beginning and at the end of the experiment. The analyzer also
continually measures and records weight over time. Biochars treated
with a process consistent with those described in this disclosure
to enhance water holding or retention capacities typically exhibit
weight loss of >5% in the interval between 38-68.degree. C.,
>1% in the interval between 43-60.degree. C. Biochars with
greater water holding or retention capacities can exhibit >5%
weight loss in the interval between 43-60.degree. C. measured using
the above described BCT.
[0127] Lastly, as illustrated in FIG. 10, plant available water is
greatly increased in treated biochar over that of raw biochar. FIG.
10 illustrates the plant available water in raw biochar, versus
treated biochar and treated dried biochar and illustrates that
treated biochar can have a plant available water percent of greater
than 35% by volume.
[0128] "Plant Available Water" is the amount of unbound water in a
material available for plants to uptake. This is calculated by
subtracting the volumetric water content at the permanent wilting
point from the volumetric water content at field capacity, which is
the point when no water is available for the plants. Field capacity
is generally expressed as the bulk water content retained in at -33
J/kg (or -0.33 bar) of hydraulic head or suction pressure.
Permanent wilting point is generally expressed as the bulk water
content retained at -1500 J/kg (or -15 bar) of hydraulic head or
suction pressure. Methods for measuring plant available water are
well-known in the industry and use pressure plate extractors, which
are commercially available or can be built using well-known
principles of operation.
[0129] 2. Adjusts pH
[0130] With regard to treatment for pH adjustment, the above
described vacuum infiltration processes and/or surfactant treatment
processes have the ability to take raw biochars having detrimental
or deleterious pHs and transform those biochars into a treated
biochar having pH that is in an optimal range for most plant
growth, and soil health. Turning to FIG. 11, a graph 1100 is
provided that shows the pH of various starting raw biochars that
were made from different starting materials and pyrolysis process
temperatures, including coconut shells 1104, pistachio shells 1101,
corn at 500.degree. C. 1105, corn at 900.degree. C. 1102, bamboo
1103, mesquite 1106, wood and coffee 1108, wood (Australia) 1109,
various soft woods 1110, 1111, 1112, 1113, 1114, 1115, 1116, 1117,
red fir at 900.degree. C. 1107, various grasses at 500.degree. C.
1118, 1119, 1120, grass 1121, and grass at 900.degree. C. 1123. The
treatment processes described in this disclosure, can be used to
alter the pH from the various undesirable pH levels and bring the
pH into the preferred, optimal range 1124 for most plant growth,
soil health and combinations of these. FIG. 12 is a chart 1200
showing percentage of germination for lettuce plants for particular
pHs, and a desired germination range 1201. A control 1204 is
compared with an optimal pH range 1202, and a distribution 1203 of
growth rates across pHs is shown.
[0131] If treated for pH adjustment, the treated biochar takes a
few days after treatment for the pH to normalize. Once normalized,
tests have proven that pH altered biochar remains at a stable pH,
typically the treatment is used to lower the stable pH to below
that of the raw biochar, for up to 12 months or more after
treatment. Although in certain situations, the pH could be altered
to be higher than the raw biochar when needed.
[0132] For example, the treatment process of the present invention
can remove and/or neutralize inorganic compounds, such as the
calcium hydroxide ((CaOH).sub.2), potassium oxide
(K.sub.2OK.sub.2OK.sub.20), magnesium oxide (MgO), magnesium
hydroxide (Mg(OH).sub.2), and many others that are formed during
pyrolysis, and are fixed to the biochar pore surfaces. These
inorganics, in particular calcium hydroxide, adversely affect the
biochar's pH, making the pH in some instances as high as 8.5, 9.5,
10.5 and 11.2. These high pH ranges are deleterious, detrimental to
crops, and may kill or adversely affect the plants, sometimes
rendering an entire field a loss.
[0133] The calcium hydroxide, and other inorganics, cannot readily
and quickly be removed by simple washing of the biochar, even in an
acid bath. It cannot be removed by drying the biochar, such as by
heating or centrifugal force. It is theorized that these techniques
and methodologies cannot reach or otherwise affect the various pore
surfaces, e.g., macro-, meso- and micro- in any viable or
efficacious manner; and thus cannot remove or otherwise neutralize
the calcium hydroxide.
[0134] Upon modification of the pore surface area by removal and/or
neutralization of deleterious substances, such as calcium
hydroxide, the pH of the biochar can be reduced to the range of
about pH 5 to about pH 8, and more preferably from about pH 6.4 to
about 7.2, and still more preferably around 6.5 to 6.8, recognizing
that other ranges and pHs are contemplated and may prove useful,
under specific environmental or agricultural situations or for
other applications. Thus, the present treated biochars, particles,
batches and both, have most, essentially all, and more preferably
all, of their pore surfaces modified by the removal, neutralization
and both, of the calcium hydroxide that is present in the starting
biochar material. These treated biochars have pHs in the range of
about 5 to about 8, about 6.5 to about 7.5, about 6.4 to about 7,
and about 6.8. Prior to and before testing, biochar is passed
through a 2 mm sieve before pH is measured. All measurements are
taken according to Rajkovich et. al, Corn growth and nitrogen
nutrition after additions of biochars with varying properties to a
temperate soil, Biol. Fertil. Soils (2011), from which the
International Biochar Initiative (IBI) method is based.
[0135] There are a wide variety of tests, apparatus and equipment
for making pH measurements. For example, and preferably when
addressing the pH of biochar, batches, particles and pore surfaces
of those particles, two appropriates for measuring pH are the Test
Method for the US Composting Council ("TMCC") 4.11-A and the pH
Test Method promulgated by the International Biochar Initiative.
The test method for the TMCC comprises mixing biochar with
distilled water in 1:5 [mass:volume] ratio, e.g., 50 grams of
biochar is added to 250 ml of pH 7.0.+-.0.02 water and is stirred
for 10 minutes; the pH is then the measured pH of the slurry. The
pH Test Method promulgated by the International Biochar Initiative
comprises 5 grams of biochar is added to 100 ml of water
pH=7.0.+-.0.02 and the mixture is tumbled for 90 minutes; the pH of
the slurry is measured at the end of the 90 minutes of
tumbling.
[0136] 3. Removing/Neutralizing Deleterious Materials
[0137] Further, the treatment processes are capable of modifying
the pore surfaces to remove or neutralize deleterious materials
that are otherwise difficult, if not for all practical purpose,
impossible to mitigate. For example, heavy metals, transition
metals, sodium and phytotoxic organics, polycyclic aromatic
hydrocarbons, volatile organic compounds (VOCs), and perhaps other
phytotoxins. Thus, by treating the biochar in accordance with the
treatment processes set forth and described above, the resulting
treated biochar has essentially all, and more preferably all, of
their pore surfaces modified by the removal, neutralization and
both, of one or more deleterious, harmful, or potentially harmful
material that is present in the starting biochar material.
[0138] For example, treatment can reduce the total percentage of
residual organic compounds (ROC), including both the percentage of
heavy ROCs and percentage of VOCs. Through treatment, the total ROC
can be reduced to 0-25% wt. %, percentage heavy ROC content can be
reduced to 0-20% wt. % and VOC content can be reduced to less than
5% wt. %. For purposes of this application, "Residual organic
compounds" (ROCs) are defined as compounds that burn off during
thermogravimetric analysis, as defined above, between 150 degrees
C. and 950 degrees C. Residual organic compounds include, but are
not limited to, phenols, polyaromatic hydrocarbons, monoaromatic
hydrocarbons, acids, alcohols, esters, ethers, ketones, sugars,
alkanes and alkenes. Of the ROCs, those that burn off using
thermogravimetric analysis between 150 degrees C. and 550 degrees
are considered light organic compounds (volatiles or VOCs), and
those that burn off between 550 degrees C. and 950 degrees C. are
heavy residual organic compounds. It should be noted that there may
be some inorganic compounds which also are burned off during TGA
analysis in these temperature ranges, but these are generally a
very low percentage of the total emission and can be disregarded in
the vast majority of cases as slight variations. In any of these
measurements, a gas chromatograph/mass spectrometer may be used if
needed for higher degrees of precision.
[0139] The percent water, total organic compounds, total light
organic compounds (volatiles or VOC) and total heavy organic
compounds, as referenced in this application as contained in a
biochar particle or particles in a sample may all be measured by
thermogravimetric analysis. Thermogravimetric analysis is performed
by a Hitachi STA 7200 analyzer or similar piece of equipment under
nitrogen flow at the rate of 110 mL/min. The biochar samples are
heated for predetermined periods of time, e.g., 20 minutes, at a
variety of temperatures between 100 and 950.degree. C. The sample
weights are measured at the end of each dwell step and at the
beginning and at the end of the experiment. Thermogravimetric
analysis of a given sample indicating percentage water in a sample
is determined by % mass loss measured between standard temperature
and 150 degrees C. Thermogravimetric analysis of a given sample
indicating percentage of residual organic compounds is measured by
percentage mass loss sustained between 150 degrees C. and 950
degrees C. Thermogravimetric analysis of a given sample indicating
percentage of light organic compounds (volatiles) is measured by
percentage mass loss sustained between 150 degrees C. and 550
degrees C. Thermogravimetric analysis of a given sample indicating
percentage of heavy organic compounds is measured by percentage
mass loss sustained between 550 degrees C. and 950 degrees C. FIG.
13 is an example of a Thermogravimetric Analysis (TGA) plot
outlining the above explanation and the measure of water, light
organics and heavy organics.
[0140] As noted above, treatment can remove or neutralize heavy
metals, transition metals, sodium and phytotoxic organics,
polycyclic aromatic hydrocarbons, volatile organic compounds
(VOCs), other phytotoxins, and even dioxins. Thus, by treating the
biochar in accordance with the treatment processes set forth and
described above, the resulting treated biochar has essentially all,
and more preferably all, of their pore surfaces modified by the
removal, neutralization or both, of one or more deleterious,
harmful, or potentially harmful material that is present in the
starting biochar material.
[0141] Dioxins may also be removed through the treatment processes
of the present invention. Dioxins are released from combustion
processes and thus are often found in raw biochar. Dioxins include
polychlorinated dibenzo-p-dioxins (PCDDs) (i.e., 75 congeners (10
are specifically toxic)); polychlorinated dibenzofurans (PCDFs)
(i.e., 135 congeners (7 are specifically toxic)) and
polychlorinated biphenyls (PCBs) (Considered dioxin-like compounds
(DLCs)).
[0142] Since some dioxins may be carcinogenic even at low levels of
exposure over extended periods of time, the FDA views dioxins as a
contaminant and has no tolerances or administrative levels in place
for dioxins in animal feed. Dioxins in animal feed can cause health
problems in the animals themselves. Additionally, the dioxins may
accumulate in the fat of food-producing animals and thus
consumption of animal derived foods (e.g. meat, eggs, milk) could
be a major route of human exposure to dioxins. Thus, if biochar is
used in animal applications, where the animals ingest the biochar,
the ability to remove dioxins from the raw biochar prior to use is
of particular significance.
[0143] Results have proven the removal of dioxins from raw biochar
by applying the treatment process of the present invention. To
demonstrate the removal of dioxins, samples of both raw biochar and
biochar, treated within the parameters set forth above, were sent
out for testing. The results revealed that the dioxins in the raw
biochar were removed through treatment as the dioxins detected in
the raw biochar sample were not detected in the treated biochar
sample. Below is a chart comparing the test results of measured
dioxins in the raw verses the treated biochar.
TABLE-US-00002 Amount Detected Amount Detected in Raw Biochar in
Treated Biochar Dioxins Sample Sample Tetradioxins 26.4 ng/Kg-dry
Not detectable Pentadioxins 5.86 ng/Kg-dry Not detectable
Hexadioxins 8.41 ng/Kg-dry Not detectable
[0144] A number of different dioxins exist, several of which are
known to be toxic or undesirable for human consumption. Despite the
test results above, it is possible that any number of dioxins could
be present in raw biochar depending on the biomass or where the
biomass is grown. It is shown, however, in the above testing, that
the treatment process of the present invention can be used to
eliminate dioxins present in raw biochar.
[0145] Seventeen tetra-octo dioxins and furan congeners are the
basis for regulatory compliance. Other dioxins are much less toxic.
Dioxins are generally regulated on toxic equivalents (TEQ) and are
represented by the sum of values weighted by Toxic Equivalency
TEQ=.SIGMA.[C.sub.i].times.TEF.sub.i
Factor (TEF)
[0146] 2,3,7,8-TCDD has a TEF of 1 (most toxic). TEQ is measured as
ng/kg WHO-PCDD/F-TEQ//kg NDs are also evaluated. Two testing
methods are generally used to determine TEQ values: EPA Method 8290
(for research and understanding at low levels (ppt-ppq); and EPA
Method 1613B (for regulatory compliance). Both are based on high
resolution gas chromatography (HRGC)/high resolution mass
spectrometry (HRMS).
[0147] The required EU Feed Value is equal to or less than 0.75
ng/kg WHO-PCDD/F-TEQ//kg. Treated biochar, in accordance with the
present invention, has shown to have TEQ dioxins less than 0.5
ng/kg WHO-PCDD/F-TEQ//kg, well below the requirement for EU Feed
limits of 0.75 ng/kg WHO-PCDD/F-TEQ//kg. As further set forth
above, treatment can reduce the amount of detectable dioxins from
raw biochar such that the dioxins are not detectible in treated
biochar. Two methods are used: EPA Method 8290 (for research and
understanding at low levels (ppt-ppq); and EPA Method 1613B (for
regulatory compliance). Both are based on high resolution gas
chromatography (HRGC)/high resolution mass spectrometry (HRMS).
[0148] 4. Pore Volume
[0149] Generally, a treated biochar sample has greater than 50% by
volume of its porosity in macropores (pores greater than 300
nanometers). Further, results indicate that greater than 75% of
pores in treated biochar are below 50,000 nanometers. Also, results
indicate that greater than 50% by volume of treated biochar
porosity are pores in the range of 500 nanometers and 100,000
nanometers. Bacterial sizes are typically 500 nanometers to several
thousand nanometers. Bacteria and other microbes have been observed
to fit and colonize in the pores of treated biochar, thus
supporting the pore size test results.
[0150] Macropore volume is determined by mercury porosimetry, which
measures the meso and/or macro porosity by applying pressure to a
sample immersed in mercury at a pressure calibrated for the minimum
pore diameter to be measured (for macroporosity this is 300
nanometers). This method can be used to measure pores in the range
of 3 nm to 360,000 nm. Total volume of pores per volumetric unit of
substance is measured using gas expansion method.
[0151] Depending upon the biomass from which the biochar is
derived, mercury porosimetry testing has shown that washing under
differential pressure, using the processes described above, can
increase the number of both the smallest and larger pores in
certain biochar (e.g., pine) and can increase the number of usable
smaller pores. Treatment of biochar using either vacuum or
surfactant does alter the percentage of total usable pores between
500 to 100,000 nanometers and further has varying impact on pores
less than 50,000 nanometers and less than 10,000 nanometers.
[0152] FIG. 14 is a chart 1400 showing the impact of treatment on
pores sizes of biochar derived from coconut. The majority of the
coconut based biochar pores are less than 10 microns. Many are less
than 1 micron. Vacuum processing of the biochar results in small
reduction of 10 to 50 micron pores, with increase of smaller pores
on vacuum processing. The mercury porosimetry results of the raw
biochar are represented by 1402 (first column in the group of
three). The vacuum treated biochar is represented by 1404 (second
column in the group of three) and the surfactant treated biochar is
1406 (third column in the group of three).
[0153] FIG. 15 is a chart 1500 showing the impact of treatment on
pores sizes of biochar derived from pine. The majority of the pine
based biochar pores are 1 to 50 microns, which is a good range for
micro-biologicals. Vacuum processing results in significant
reduction of the 10 to 50 micron pores, with an increase of
smallest and largest pores. The mercury porosimetry results of the
raw biochar are represented by 1502 (first column in the group of
three). The vacuum treated biochar is represented by 1504 (second
column in the group of three) and the surfactant treated biochar is
3006 (third column in the group of three).
[0154] 5. Electrical Conductivity
[0155] The electrical conductivity (EC) of a solid material-water
mixture indicates the amount of salts present in the solid
material. Salts are essential for plant growth. The EC measurement
detects the amount of cations or anions in solution; the greater
the amount of ions, the greater the EC. The ions generally
associated with salinity are Ca.sup.2+, Mg.sup.2+, K.sup.+,
Na.sup.+, H.sup.+, NO.sub.3.sup.-, SO.sub.4.sup.2-, Cl--,
HCO.sub.3.sup.-, OH.sup.-. Electrical conductivity testing of
biochar was done following the method outlined in the USDA's Soil
Quality Test Kit Guide and using a conventional EC meter. The
biochar sample is mixed with DI water in a 1:1 biochar to water
ratio on a volume basis. After thorough mixing, the EC (dS/m) is
measured while the biochar particles are still suspended in
solution. Treatment, as outlined in this disclosure can be used to
adjust the ions in the char. Testing of treated biochar shows its
EC is generally greater than 0.2 dS/m and sometimes greater than
0.5 dS/m.
[0156] 6. Cation Exchange Capacity
[0157] One method for cation exchange capacity ("CEC")
determination is the use of ammonium acetate buffered at pH 7.0
(see Schollenberger, C. J. and Dreibelbis, E R. 1930, Analytical
methods in base-exchange investigations on soils, Soil Science, 30,
161-173). The material is saturated with 1M ammonium acetate,
(NH.sub.4OAc), followed by the release of the NH.sub.4.sup.+ ions
and its measurement in meq/100 g (milliequivalents of charge per
100 g of dry soil) or cmolc/kg (centimoles of charge per kilogram
of dry soil). Instead of ammonium acetate another method uses
barium chloride according to Mehlich, 1938, Use of triethanolamine
acetate-barium hydroxide buffer for the determination of some base
exchange properties and lime requirement of soil, Soil Sci. Soc.
Am. Proc. 29:374-378. 0.1 M BaCl.sub.2 is used to saturate the
exchange sites followed by replacement with either MgSO.sub.4 or
MgCl.sub.2.
[0158] Indirect methods for CEC calculation involves the estimation
of extracted Ca.sub.2.sup.+, Mg.sub.2.sup.+, K.sup.+, and Na.sup.+
in a standard soil test using Mehlich 3 and accounting for the
exchangeable acidity (sum of H.sup.+, Al.sub.3.sup.+,
Mn.sub.2.sup.+, and Fe.sub.2.sup.+) if the pH is below 6.0 (see
Mehlich, A. 1984, Mehlich-3 soil test extractant: a modification of
Mehlich-2 extractant, Commun. Soil Sci. Plant Anal. 15(12):
1409-1416). When treated using the above methods, including but not
limited by washing under a vacuum, treated biochars generally have
a CEC greater than 5 millieq/l and some even have a CEC greater
than 25 (millieq/l). To some extent, treatment can be used to
adjust the CEC of a char.
[0159] 7. Anion Exchange Capacity
[0160] Similar to CEC measurements, anion exchange capacity ("AEC")
may be calculated directly or indirectly-saturated paste extraction
of exchangeable anions, Cl.sup.-, NO.sub.3.sup.-, SO.sub.4.sup.2-,
and PO.sub.4.sup.3- to calculate anion sum or the use of potassium
bromide to saturate anions sites at different pHs and repeated
washings with calcium chloride and final measurement of bromide
(see Rhoades, J. D. 1982, Soluble salts, p. 167-179. In: A. L. Page
et al. (ed.) Methods of soil analysis: Part 2: Chemical and
microbiological properties; and Michael Lawrinenkoa and David A.
Laird, 2015, Anion exchange capacity of biochar, Green Chem., 2015,
17, 4628-4636). When treated using the above methods, including but
not limited by washing under a vacuum, treated biochars generally
have an AEC greater than 5 millieq/l and some even have an AEC
greater than 20 (millieq/l). To some extent, treatment can be used
to adjust the CEC of a char.
[0161] 8. Hydrophilicity/Hydrophobicity
[0162] The ability to control the hydrophilicity of the pores
provides the ability to load the biochar particles with larger
volumes of inoculant. The more hydrophilic the more the biochars
can accept inoculant or infiltrate. Tests show that biochar treated
in accordance with the above processes, using either vacuum or
surfactant treatment processes increase the hydrophilicity of raw
biochar. Two tests may be used to test the
hydrophobicity/hydrophilicity of biochar: (i) the Molarity of
Ethanol Drop ("MED") Test; and (ii) the Infiltrometer Test.
[0163] The MED test was originally developed by Doerr in 1998 and
later modified by other researchers for various materials. The MED
test is a timed penetration test that is noted to work well with
biochar soil mixtures. For 100% biochar, penetration time of
different mixtures of ethanol/water are noted to work better.
Ethanol/Water mixtures verses surface tension dynes were correlated
to determine whether treated biochar has increased hydrophilicity
over raw biochar. Seven mixtures of ethanol and deionized water
were used with a sorption time of 3 seconds on the biochar.
[0164] Seven solutions of deionized ("DI") water with the following
respective percentages of ethanol: 3, 5, 11, 13, 18, 24 and 36,
were made for testing. The test starts with a mixture having no DI.
If the solution is soaked into the biochar in 3 seconds for the
respective solution, it receives the corresponding Hydrophobicity
Index value below.
TABLE-US-00003 Ethanol % Hydrophobicity Index 0: DI Water 0 Very
Hydrophillic 3% 1 5% 2 11% 3 13% 4 18% 5 24% 6 36% 7 Strongly
Hydrophillic
[0165] To start the test the biochar ("material/substrate") is
placed in convenient open container prepared for testing.
Typically, materials to be tested are dried 110.degree. C.
overnight and cooled to room temperature. The test starts with a
deionized water solution having no ethanol. Multiple drips of the
solution are then laid onto the substrate surface from low height.
If drops soak in less than 3 seconds, test records substrate as
"0". If drops take longer than 3 seconds or don't soak in, go to
test solution 1. Then, using test solution 1, multiple drops from
dropper are laid onto the surface from low height. If drops soak
into the substrate in less than 3 seconds, test records material as
"1". If drops take longer than 3 seconds, or don't soak in, go to
test solution 2. Then, using test solution 2, multiple drops from
dropper laid onto the surface from low height. If drops soak into
the substrate in less than 3 seconds, test records material as "2".
If drops take longer than 3 seconds, or don't soak in, go to test
solution 3. Then, using test solution 3, multiple drops from
dropper laid onto the surface from low height. If drops soak into
the substrate in less than 3 seconds, test records material as "3".
If drops take longer than 3 seconds, or don't soak in, go to
solution 4.
[0166] The process above is repeated, testing progressively higher
numbered MED solutions until the tester finds the solution that
soaks into the substrate in 3 seconds or less. The substrate is
recorded as having that hydrophobicity index number that correlates
to the solution number assigned to it (as set forth in the chart
above).
[0167] Example test results using the MED test method is
illustrated below.
TABLE-US-00004 MATERIAL HYDROPHOBICITY INDEX Raw Biochars 3 to 5
Treated Biochars 1 to 3
[0168] Another way to measure and confirm that treatment decreases
hydrophobicity and increases hydrophilicity is by using a mini disk
infiltrometer. For this test procedure, the bubble chamber of the
infiltrometer is filled three quarters full with tap water for both
water and ethanol sorptivity tests. Deionized or distilled water is
not used. Once the upper chamber is full, the infiltrometer is
inverted and the water reservoir on the reserve is filled with 80
mL. The infiltrometer is carefully set on the position of the end
of the mariotte tube with respect to the porous disk to ensure a
zero suction offset while the tube bubbles. If this dimension is
changed accidentally, the end of the mariotte tube should be reset
to 6 mm from the end of the plastic water reservoir tube. The
bottom elastomer is then replaced, making sure the porous disk is
firmly in place. If the infiltrometer is held vertically using a
stand and clamp, no water should leak out.
[0169] The suction rate of 1 cm is set for all samples. If the
surface of the sample is not smooth, a thin layer of fine biochar
can be applied to the area directly underneath the infiltrometer
stainless steel disk. This ensures good contact between the samples
and the infiltrometer. Readings are then taken at 1 min intervals
for both water and ethanol sorptivity test. To be accurate, 20 mL
water or 95% ethanol needs to be infiltrated into the samples.
Record time and water/ethanol volumes at the times are
recorded.
[0170] The data is then processed to determine the results. The
data is processed by the input of the volume levels and time to the
corresponding volume column. The following equation is used to
calculate the hydrophobicity index of R
I=at+b {square root over (t)} [0171] a: Infiltration Rate, cm/s
[0172] b: Sorptivity, cm/s.sup.1/2
[0172] R = 1.95 * b ethanol b water ##EQU00001##
[0173] FIG. 16 illustrates one example of the results of a
hydrophobicity test performed on raw biochar, vacuum treated
biochar and surfactant treated biochar. As illustrated, both the
vacuum treated and surfactant treated biochar are more hydrophilic
than the raw biochar based upon the lower Index rating. In
accordance with the test data in FIG. 16, the hydrophobicity of raw
biochar was reduced 23% by vacuum processing and 46% by surfactant
addition.
[0174] As an example, raw biochar and treated biochar were tested
with ethanol and water, five times for each. The results below show
that the hydrophobicity index of the treated biochar is lower than
the raw biochar. Thus, tests demonstrate that treating the biochar,
using the methods set forth above, make the biochar less
hydrophobic and more hydrophilic.
TABLE-US-00005 MATERIAL HYDROPHOBICITY INDEX Dried Raw Biochar 12.9
Dried Vacuum Treated Biochar 10.4 Dried Surfactant Treated Biochar
7.0 As Is Raw Biochar 5.8 As Is Vacuum Treated Biochar 2.9
[0175] Further, through the treatment processes of the present
invention, the biochar can also be infused with soil enhancing
agents. By infusing liquid into the pore structure through the
application of positive or negative pressure and/or a surfactant,
alone or in combination, provides the ability to impregnate the
macropores of the biochar with soil enhancing solutions and solids.
The soil enhancing agent may include, but not be limited to, any of
the following: water, water solutions of salts, inorganic and
organic liquids of different polarities, liquid organic compounds
or combinations of organic compounds and solvents, mineral and
organic oils, slurries and suspensions, supercritical liquids,
fertilizers, plant growth promoting rhizobacteria, free-living and
nodule-forming nitrogen fixing bacteria, organic decomposers,
nitrifying bacteria, phosphate solubilizing bacteria, biocontrol
agents, bioremediation agents, saprotrophic fungi, ectomycorrhizae
and endomycorrhizae, among others.
[0176] 9. Impregnation and/or Inoculation with Infiltrates or
Additives
[0177] In addition to mitigating or removing deleterious pore
surface properties, by treating the pores of the biochar through a
forced, assisted, accelerate or rapid infiltration process, such as
those described above, the pore surface properties of the biochar
can be enhanced. Such treatment processes may also permit
subsequent processing, may modify the pore surface to provide
predetermined properties to the biochar, and/or provide
combinations and variations of these effects. For example, it may
be desirable or otherwise advantageous to coat substantially all,
or all of the biochar macropore and mesopore surfaces with a
surface modifying agent or treatment to provide a predetermined
feature to the biochar, e.g., surface charge and charge density,
surface species and distribution, targeted nutrient addition,
magnetic modifications, root growth facilitator, and water
absorptivity and water retention properties.
[0178] By infusing liquids into the pores of biochar, it has been
discovered that additives infused within the pores of the biochar
provide a time release effect or steady flow of some beneficial
substances to the environment, e.g. root zones of the plants, and
also can improve and provide a more beneficial environment for
microbes which may reside or take up residence within the pores of
the biochar. In particular, additive infused biochars placed in the
soil prior to or after planting can dramatically reduce the need
for high frequency application of additives, minimize losses caused
by leaching and runoff and/or reduce or eliminate the need for
controlled release fertilizers. They can also be exceptionally
beneficial in animal feed applications by providing an effective
delivery mechanism for beneficial nutrients, pharmaceuticals,
enzymes, microbes, or other substances.
[0179] For purposes of this application, "infusion" of a liquid or
liquid solution into the pores of the biochar means the
introduction of the liquid or liquid solution into the pores of the
biochar by a means other than solely contacting the liquid or
solution with the biochar, e.g., submersion. The infusion process,
as described in this application in connection with the present
invention, includes a mechanical, chemical or physical process that
facilitates or assist with the penetration of liquid or solution
into the pores of the biochar, which process may include, but not
be limited to, positive and negative pressure changes, such as
vacuum infusion, surfactant infusion, or infusion by movement of
the liquid and/or biochar (e.g., centrifugal force and/or
ultrasonic waves) or other method that facilitates, assists, forces
or accelerates the liquid or solution into the pores of the
biochar.
[0180] Prior to infusing the biochar, the biochar, as described in
detail above, may be washed and/or moisture adjusted. FIG. 17 is a
flow diagram 1700 of one example of a method for infusing biochar
with an additive. Optionally, the biochar may first be washed or
treated at step 1702, the wash may adjust the pH of the biochar, as
described in more detail above, or may be used to remove elemental
ash and other harmful organics that may be unsuitable for the
desired infused additive. Optionally, the moisture content of the
biochar may then be adjusted by drying the biochar at step 1704,
also as described in further detail above, prior to infusion of the
additive or inoculant at step 1706.
[0181] In summary, the infusion process may be performed with or
without any washing, prior pH adjustment or moisture content
adjustment. Optionally, the infusion process may be performed with
the wash and/or the moisture adjustment step. All the processes may
be completed alone or in the conjunction with one or more of the
others.
[0182] Through the above process of infusing the additive into the
pores of the biochar, the pores of the biochar may be filled by
25%, up to 100%, with an additive solution, as compared to 1-20%
when the biochar is only submerged in the solution or washed with
the solution for a period of less than twelve hours. Higher
percentages may be achieved by washing and/or drying the pores of
the biochar prior to infusion.
[0183] Data have been gathered from research conducted comparing
the results of soaking or immersion of biochar in liquid versus
vacuum impregnation of liquid into biochar. These data support the
conclusion that vacuum impregnation provides greater benefits than
simple soaking and results in a higher percentage volume of
moisture on the surface, interstitially and in the pores of the
biochar.
[0184] In one experiment, equal quantities of pine biochar were
mixed with equal quantities of water, the first in a beaker, the
second in a vacuum flask. The mixture in the beaker was
continuously stirred for up to 24 hours, then samples of the
suspended solid were taken, drained and analyzed for moisture
content. The mixture in the vacuum flask was connected to a vacuum
pump and negative pressure of 15'' was applied. Samples of the
treated solid were taken, drained and analyzed for moisture
content. FIG. 18 is a chart illustrating the results of the
experiment. The lower graph 1802 of the chart, which shows the
results of soaking over time, shows a Wt. % of water of
approximately 52%. The upper graph 1804 of the chart, which shows
the results of vacuum impregnation over time, shows a Wt. % of
water of approximately 72%.
[0185] FIGS. 19a and 19b show two charts that further illustrate
that the total water and/or any other liquid content in processed
biochar can be significantly increased using vacuum impregnation
instead of soaking. FIG. 19a compares the mL of total water or
other liquid by retained by 1 mL of treated biochar. The graph 1902
shows that approximately 0.17 mL of water or other liquid are
retained through soaking, while the graph 1904 shows that
approximately 0.42 mL of water or other liquid are retained as a
result of vacuum impregnation. FIG. 19b shows that the retained
water of a biochar subjected to soaking consists entirely of
surface and interstitial water 1906, while the retained water of a
biochar subjected to vacuum impregnation consists not only of
surface and interstitial water 1908a, but also water impregnated in
the pores of the biochar 1908b.
[0186] In addition, as illustrated by FIG. 20, the amount of
moisture content impregnated into the pores of vacuum processed
biochars by varying the applied (negative) pressure during the
treatment process. The graphs of four different biochars all show
how the liquid content of the pours of each of them increase to
100% as the vacuum is increased.
[0187] The pores may be substantially filled or completely filled
with additives to provide enhanced performance features to the
biochar, such as increased plant growth, nutrient delivery, water
retention, nutrient retention, disadvantageous species control,
e.g., weeds, disease causing bacteria, insects, volunteer crops,
etc. By infusing liquid deep into the pore structure through the
application of positive or negative pressure, surfactant and/or
ultrasonic waves, alone or in combination, provides the ability to
impregnate the mesopores and macropores of the biochar with
additives, that include, but are not limited to, soil enhancing
solutions and solids. It should be noted that using these infusion
techniques allows for impregnating the pores with additives that
are more fragile. For example, since heating is not a requirement
for these infusion techniques, microbes, chemicals, or compounds
can be infused without risk of destroying the microbes or changing
chemicals or compounds due to high temperatures. Also the process
can be done at low temperatures to infuse chemicals that have low
boiling points to keep them a liquid.
[0188] The additive may be a soil enhancing agent that includes,
but is not be limited to, any of the following: water, water
solutions of salts, inorganic and organic liquids of different
polarities, liquid organic compounds or combinations of organic
compounds and solvents, mineral and organic oils, slurries and
suspensions, supercritical liquids, fertilizers, PGPB (including
plant growth promoting rhizobacteria, free-living and
nodule-forming nitrogen fixing bacteria, organic decomposers,
nitrifying bacteria, and phosphate solubilizing bacteria), enzymes,
biocontrol agents, bioremediation agents, saprotrophic fungi,
ectomycorrhizae and endomycorrhizae, among others.
[0189] Fertilizers that may be infused into the biochar include,
but are not limited to, the following sources of nitrogen,
phosphorous, and potassium: urea, ammonium nitrate, calcium
nitrate, sulfur, ammonium sulfate, monoammonium phosphate, ammonium
polyphosphate, potassium sulfate, or potassium chloride.
[0190] Similar beneficial results are expected from other
additives, such as: bio pesticides; herbicides; insecticides;
nematicides; plant hormones; plant pheromones; organic or inorganic
fungicides; algicides; antifouling agents; antimicrobials;
attractants; biocides, disinfectants and sanitizers; miticides;
microbial pesticides; molluscicides; bacteriacides; fumigants;
ovicides; repellents; rodenticides, defoliants, desiccants; insect
growth regulators; plant growth regulators; beneficial microbes;
and, microbial nutrients or secondary signal activators, that may
also be added to the biochar in a similar manner as a fertilizer.
Additionally, beneficial macro- and micro-nutrients such as,
calcium, magnesium, sulfur, boron, zinc, iron, manganese,
molybdenum, copper and chloride may also be infused into the
biochar in the form of a water solution or other solvent
solution.
[0191] Examples of compounds, in addition to fertilizer, that may
be infused into the pores of the biochar include, but are not
limited to: phytohormones, such as, abscisic acid (ABA), auxins,
cytokinins, gibberellins, brassinosteroies, salicylic acid,
jasmonates, planet peptide hormones, polyamines, karrikins,
strigolactones; 2,1,3-Benzothiadiazole (BTH), an inducer of
systemic acquired resistance that confers broad spectrum disease
resistance (including soil borne pathogens); signaling agents
similar to BTH in mechanism or structure that protects against a
broad range or specific plant pathogens; EPSPS inhibitors;
synthetic auxins; photosystem I inhibitors photosystem II
inhibitors; and HPPD inhibitors.
[0192] In one example, a 1000 ppm NO.sub.3.sup.- N fertilizer
solution is infused into the pores of the biochar. As discussed
above, the method to infuse biochar with the fertilizer solution
may be accomplished generally by placing the biochar in a vacuum
infiltration tank or other sealable mixing vessel, chamber or tank.
When using vacuum infiltration, a vacuum may be applied to the
biochar and then the solution may be introduced into the tank.
Alternatively, the solution and biochar may both be introduced into
the tank and, once introduced, a vacuum is applied. Based upon the
determined total pore volume of the biochar or the incipient
wetness, the amount of solution to introduce into the tank
necessary to fill the pore of the biochar can be determined. When
infused in this manner, significantly more nutrients can be held in
a given quantity of biochar versus direct contact of the biochar
with the nutrients alone.
[0193] When using a surfactant, the biochar and additive solution
may be added to a tank along with 0.01-20% of surfactant, but more
preferably 1-5% of surfactant by volume of fertilizer solution. The
surfactant or detergent aids in the penetration of the wash
solution into the pores of the biochar. The same or similar
equipment used in the vacuum infiltration process can be used in
the surfactant treatment process. Although it is not necessary to
apply a vacuum in the surfactant treatment process, the vacuum
infiltration tank or any other mixing vessel, chamber or tank can
be used. Again, while it is not necessary to apply a vacuum, a
vacuum may be applied or the pressure in the vessel may be changed.
Further, the surfactant can be added with or without heat or
cooling either of the infiltrate, the biochar, the vessel itself,
or any combination of the three.
[0194] The utility of infusing the biochar with an additive is that
the pores in biochar create a protective "medium" for carrying said
additive to the environment. As an example when the additive is a
fertilizer the nutrient infused biochar provides a more constant
supply of available nutrients to the soil and plants and continues
to act beneficially, potentially sorbing more nutrients or
nutrients in solution even after introduction to the soil. By
infusing the nutrients in the pores of the biochar, immediate
oversaturation of the soil with the nutrients is prevented and a
time released effect is provided. This effect is illustrated in
connection with FIGS. 18 and 19 below. As demonstrated in
connection with FIGS. 18 & 19 below, biochars having pores
infused with additives, using the infusion methods described above,
have been shown to increase nutrient retention, increase crop
yields and provide a steadier flow of fertilizer to the root zones
of the plants.
[0195] FIG. 21 is a chart showing improved mass yield in lettuce
with fertilizer infused biochar using vacuum impregnation. FIG. 21
compares the mass yield results of lettuce grown in different
environments. One set of data measurements represents lettuce grown
in soil over a certain set time period with certain, predetermined
amounts of fertilizer infused into the biochar. A second set of
data represents lettuce grown in soil over a certain set period of
time with the same amount of unimpregnated biochar added at the
beginning of the trial and certain predetermined amounts of NPK
solution added to the soil over time. Growth comparisons were made
between the same amount of fertilizer solution infused into the
biochar as added directly to the soil, using the same watering
schedule. As illustrated, the test results demonstrated a 15% yield
increase in growth when infusing approximately 750 mg/pot of NPK
into the biochar than when applying it directly to the soil.
Similarly, the same mass yield of lettuce is achieved at 400 mg
NPK/pot with infused biochar than at 750 mg/pot when adding the
fertilizer solution directly to the soil.
[0196] FIG. 22 is a chart illustrating the concentration of nitrate
(N) found in distilled water after washing differentially treated
biochar. In the illustrated example, two biochar samples (500 ml
each) mixed with 1000 ppm NO.sub.3.sup.- N fertilizer solution were
washed with distilled water. The resulting wash was then tested for
the presence of nitrate (N), measured in ppm. In one sample, the
biochar was submerged in and mixed with the nutrient solution. In
the other example, the biochar was mixed or washed with a nutrient
solution augmented with 1% surfactant by volume (i.e., 1 ml of
surfactant per 100 ml of fertilizer solution) in a tumbler. In both
examples, the biochar was not dried completely before infusion with
the NO.sub.3.sup.- N fertilizer solution, but used as received with
a moisture content of approximately 10-15%. In both examples, the
biochar was mixed with solution and/or surfactant (in the case of a
second sample) with a bench scale tumbler, rotating the drum for
four (4) minutes without vacuum. The results demonstrate that the
biochar treated with the 1% surfactant increases the efficiency of
infiltrating nitrate fertilizer into biochar and then demonstrates
the release of the nutrient over time. To yield the above data, the
test was repeated six times for each treatment sample, with 10
washes for each sample per repeat test.
[0197] The above are only a few examples of how additive infused
biochar may be produced for different uses. Those skilled in the
art will recognize that there may be other mechanisms for infusing
fertilizer or other soil additives into the pores of the biochar
without departing from the scope of the invention. Those skilled in
the art will further recognize that the present invention can be
used on any type of soil application, including, but not limited
to, the following: crops, turf grasses, potted plants, flowering
plants, annuals, perennials, evergreens and seedlings, as will be
further described below.
[0198] For example, in another implementation, additive infused
biochar may be produced for use for consumption by animals and/or
humans. Biochar may be infused in the same manner as described
above with nutrients (such as carbohydrates, minerals, proteins,
lipids), vitamins, drugs and/or other supplements (such as enzymes
or hormones, to name a few), or a combination of any of the
foregoing, for consumption by either humans and/or animals.
Coloring, flavor agents and/or coating may also be infused into the
pores of the biochar or applied to the surface. The foregoing may
be included to enhance the performance of the substance in the
digestive tract or to ease or facilitate the ingestion of the
biochar.
[0199] D. Biochar as a Habitat for Microorganisms
[0200] Biotechnology, specifically the use of biological organisms,
usually microorganisms, to address chemical, industrial, medical,
or agricultural problems is a growing field with new applications
being discovered daily. To date, much research has focused on
identifying, developing, producing and deploying microbes for
various uses. However, despite much work on the microbes
themselves, relatively little work has been performed on how to
carry, deliver, and encourage the successful establishment of these
microbes in their targeted environment. Most current technology for
microbial carriers in agriculture is based on technologies or
products that are highly variable and, in many cases, lead to
highly unpredictable performance of microbes in the field. For
example, many commercial microbes in agricultural settings are
delivered on peat, clay, or other carriers derived from natural
sources, accompanied by limited engineering or process control.
[0201] Biochar have a proclivity to interact positively with many
microbes relevant to plant health, animal health, and human public
health applications. In fact, there has been a level of initial
research focused on inoculating biochar with microbes and/or using
biochar in conjunction with microbes or materials with microbes,
e.g. compost. See co-owned U.S. Pat. No. 8,317,891 Method for
Enhancing Soil Growth Using Bio-char and Fischer et al., and
Synergisms between compost and biochar for sustainable soil
amelioration 2012
http://www.intechopen.com/source/pdfs/27163/InTech-Synergisms_between_com-
post_and_biochar_for_sustainable_soil_amelioration.pdf.
[0202] However, biochars, especially in raw form, often suffer from
many characteristics which make their interaction with microbial
organisms extremely unpredictable. Key among these undesirable
characteristics is a high degree of variability. Because of this
and other factors, biochar has been, to date, unused in large scale
commercial biotechnology applications. There are several methods by
which this variability can be ameliorated. At a high level, the
methods to overcome these challenges fall into two categories: (i)
making the biochar a more favorable habitat for the
microbes--either by modifying its properties, adding materials
beneficial to microbes, or removing materials deleterious to
microbes, or (ii) inoculating, applying, or immobilizing the
microbes on the biochar in ways that mitigate the underlying
variability in the material. Both of these high-level methods can
be used independently or in conjunction and have been shown to have
a significant impact on the suitability of biochar in many
biotechnology applications.
[0203] Before delving into the varying treatment methods that will
turn the biochar into a microbial carrier or co-deploying with
microbes, it is important to be able to view biochar as a habitat
for microbes. Biochar, especially treated biochar, has many
physical properties that make it interesting as a microbial
habitat. The most obvious of these is its porosity (most biochars
have a surface area of over 100 m2/g and total porosity of 0.10
cm3/cm3 or above). Furthermore, many biochars have significant
water holding and nutrient retention characteristics which may be
beneficial to microbes. Previous disclosure has outlined how these
characteristics can be further improved with treatment, e.g., U.S.
patent application Ser. No. 15/156,256, filed on May 16, 2016, and
titled Enhanced Biochar.
[0204] However, recent data indicates that the Earth may be home to
more than one trillion independent species of microbes (See Kenneth
J. Locey and Jay T. Lennon, Scaling laws predict global microbial
diversity, Proceedings of the National Academy of Science, vol. 113
no. 21 (see full text at
http://www.pnas.org/content/113/21/5970.full). Clearly, each of
these microbial species does not require an identical habitat. In
fact, many have evolved in different conditions and thrive in
different environments. Biochar, due to its organic origins,
porosity, and amenability to treatment seems to be an extremely
desirable base product to be used in the construction of microbial
carriers or co-deployment of microbes. If the properties of the
biochar can be made to match the properties expected by particular
microbes, or groups of microbes, empirical data has shown that a
much greater impact can be delivered in Many applications--whether
the targeted biochar is used as a carrier, substrate, co-deployed
product, or merely is introduced into the same environment at a
separate time. It stands to reason, as many real-world environments
are composed of very complex microbial ecosystems, that giving
certain microbes in these ecosystems a more favorable habitat, can
ultimately help those microbes to become more successfully
established, and potentially shift the entire ecosystem based on
their improved ability to compete for resources. Clearly this is a
very desirable characteristic when the successful deployment and
establishment of a targeted microbe into a new environment is a
desired outcome.
[0205] There are many properties of a habitat which may be
important to certain microbes, but some of the most important are:
pH, hydrophobicity or hydrophilicity, ability to hold moisture,
ability to retain and exchange certain types of nutrients, ion
exchange capacity (cationic and anionic), physical protection from
predatory or competitive microbes or protozoa (usable and
inhabitable porosity), presence or absence of nutrients,
micronutrients, or sources of metabolic carbon, ability to host
other symbiotic microbes or plant systems (such as plant root
tissue), or others which may be important to various types or
species of microbes. Ability to either enhance or suppress the
availability of certain enzymes can also be an extremely important
factor in building a viable habitat. This invention focuses on
methods and systems that can be used to consistently produce
biochar which has these targeted characteristics, methods that can
be used to effectively create a particular formulation of biochar
targeted to match a particular microbe or group of microbes, and
techniques for deploying the desired microbes along with this
targeted biochar, through inoculation, co-deployment, integrated
growth/fermentation, or other methods.
[0206] By using treatment properties disclosed previously, proper
feedstock selection, and control of the pyrolysis process, the
following are some, but not all, of the properties that can be
consistently targeted and controlled at production scales to
improve the biochar for use with microbes or as a microbial
carrier. Examples of those properties include (1) pH, (2)
hydrophobicity, (3) sodium levels, (4) usable pore size
distribution and usable pore volume, (5) particle size and
distribution, (6) exterior and interior surface geometry, (7)
nutrient exchange, (8) useable carbon or energy source, (9) toxic
materials or compounds, (10) surface structure/crystals/tortuosity,
(11) compatibility with biofilm formations, (12) surface charge,
(13) enzyme activity and (14) sterilization.
[0207] 1. pH
[0208] It is well known that various microbes prefer varying levels
of acidity or alkalinity. For example, acidophiles have evolved to
inhabit extremely acidic environments. Likewise, aikaliphiles
prefer more basic (alkali) environments. It has been clearly shown
that the methods outlined for treating biochars can product
targeted pH values that can be sustained over long periods of
time.
[0209] 2. Hydrophobicity
[0210] There are several common sources of hydrophobicity in porous
carbonaceous materials. One of them is the occurrence of
hydrophobic organic compounds on the surface of the char--typically
residual from the pyrolysis process. Targeted removal of these
compounds is a method to improve the hydrophobicity of porous
carbonaceous substances. These compounds can be removed in a
non-selective way by increasing the pyrolysis temperature of the
biomass to a level at which the compounds will disassociate with
the material and become gaseous. This method, while useful, is very
broad, and can also remove other desirable compounds as well as
changing the surface chemistry of the residual carbon, increasing
ash percentages, or reducing carbon yield by reacting and removing
more carbon than is necessary. These compounds can also be
selectively removed by the application of a targeted solvent using
the mechanisms previously disclosed to infiltrate liquids into the
pore volume of the material. This method is also effective, and has
shown to be much more predictable in the removal of certain
compounds. Since the vast majority of microbes rely heavily on
water for both transport and life, the easy association of water
with a material has a large bearing on its ability to sustain
microbial life.
[0211] 3. Sodium Levels
[0212] Differing types of microbes have varying proclivities for
the presence of sodium. Some microbes Halobacterium spp.,
Salinibacter ruber, Wallemia ichthyophaga prefer high levels of
salinity, while others prefer moderate or limited levels of sodium.
Sodium can be removed from biochar by either simple washing, or
more preferably and effectively, treatment methods which infuse a
solvent (most commonly water, although others may be used) into the
pores of the material. Sodium can be added, by using the same
methods except instead of using a solvent, the liquid being washed
with or infused is a solution high in sodium content. Additionally,
since sodium usually manifests itself as a cation in solution,
temporary or permanent adjustment of the cationic exchange capacity
(CEC) of the material through treatment which impacts the ability
of the material to exchange cations. Lowering the CEC of the
material will in many cases reduce its ability to exchange sodium
cations, while raising the CEC will typically enhance the ability
of the material to exchange sodium cations, with exceptions
occurring if other cations are present in quantities that cause
them to preferentially exchange instead of the sodium cations
present. Finally, differing biomass feedstock contains differing
levels of sodium--selecting an appropriate feedstock prior to
pyrolysis will result in a raw or untreated biochar with reasonably
controlled levels of sodium. For example, pine wood, when
pyrolyzed, results in a raw char with lower levels of sodium, while
coconut shells result in char with higher levels of sodium after
pyrolysis.
TABLE-US-00006 Untreated Untreated Coconut Untreated Pine Pine ASH
Composition Shell Biochar Biochar #1 Biochar #2 Ultimate Analysis -
Moisture free results Ash 6.7% 9.2% 3.6% Ash Composition Sodium
Oxide, as 5.7% 1.2% 0.8% Na2O
Regardless, it should be clear that there are various methods
available to produce final product with a targeted sodium level,
making it suitable for various microbes depending on their
preference for an environment with a certain sodium level.
[0213] 4. Usable Pore Size Distribution and Usable Pore Volume
[0214] One very important quality of a microbial habitat is the
availability of shelter from environmental or biological hazards. A
few examples of environmental hazards are high temperature, UV
radiation, or low moisture, while an example of a biological hazard
is the existing of predatory multicellular microbes such as
protozoa, including both flagellates and ciliates. In order for a
particle or material to provide shelter for microbes, at least two
conditions must be present: (i) The material must consist of pores
or openings of a size which can be inhabited by the microbe in
question (ii) but prevent the hazard from entering (e.g. pore size
smaller than the size of predators, such as protozoa, or deep
enough to be shaded from UV rays) and, (iii) the pores mentioned
previously must be usable--namely, they should not be occupied by
solid matter (clogged) and/or they should not contain substances
that are toxic or undesirable for the microbe in question. In some
cases, the pore size distribution of a biochar can be adjusted by
the selection of the biomass feedstock to be pyrolyzed and the
conditions of the pyrolysis process itself. For example, pine wood
has a relatively narrow pore size distribution, with most pores
falling in the range from 10-70 .mu.m. Coconut shells, on the other
hand, have a much wider size distribution, with many pores below 1
.mu.m, and also a high percentage of porosity above 100 .mu.m. It
is theorized that materials with pores of a single size or where
most pores are of similar size can potentially be good carriers or
habitats for certain, targeted microbes, while materials consisting
of broader ranges of pore sizes may be better habitats for
communities, consortia or groups of microbes, where each microbe
may prefer a slightly different pore size. Furthermore, the pore
size of a material may also be controlled during the pyrolysis
process by increasing temperature or performing "activation" or
other steps common in activated carbon production to react or
remove carbon, leaving larger pores, or exposing availability of
pores that were once inaccessible from the exterior surface of the
material. Adjusting the particle size of the material may also
change the pore size distribution in at least two ways: (i)
exposing pores that were not available or accessible previously, or
(ii) destroying larger pores by fracturing, splitting, or dividing
them. In many cases, raw biochar may contain a proper pore size
distribution, but for one reason or another, the pores are not
usable by the microbes in question. In other cases, the pore size
distribution provided by the natural feedstock may be undesirable.
Both properties may also be impacted through treatment of the raw
biochar itself. Larger pores can be created using strong acids or
other caustic substances either by simple washing or through forced
or rapid infusion into the pores. Conversely, a material with fewer
usable pores may be created by intentionally "clogging" or filling
the larger pores with either solids, gums, or liquids designed to
stay resident in the pores themselves. This treatment may be done
in a controlled way to only partially fill the pores. For example,
one could infuse a limited amount of heated liquid, such as a
resin, that will become solid at normal atmospheric temperatures.
If the volume of liquid used is less than the available pore volume
of the material being infused, some of the porosity of the material
will be left untreated and available for use. Most importantly, and
most commonly, usable pore volume may be increased through the act
of simply removing contaminants (physical or chemical) from the
pores. Rapid infusion and extraction of liquids may be used to
accomplish this. As discussed previously, appropriate solvents may
be infused or extracted to remove chemical contaminants.
Additionally, gasses or liquids may be driven into or out of the
pores to force the removal of many solid obstructions, such as
smaller particles of ash or simply smaller particles of raw biochar
which may have become lodged in the pore in question. Regardless of
the mechanism used, it has been shown that the available,
uncontaminated, usable pore volume and pore size has a major role
in determining the efficacy biochars in microbial roles.
[0215] FIGS. 23 and 24 are images that show how different sized
bacteria will fit in different biochar pore size structures. FIG.
2.3 is rod-shaped gram-positive bacteria, Bacillus thuringiensis
israelensis, in a treated pine biochar, with pore openings of
.about.10-20 .mu.m and bacteria of .about.2-5 .mu.m. FIG. 24 is
rod-shaped gram-negative bacteria, Serratia liquefaciens, in a
treated coconut shell biochar, with pore openings of .about.2-10
.mu.m and bacteria of .about.1-2 .mu.m.
[0216] In addition, total pore volume in the size of 5-50 .mu.m has
been shown to correlate with microbial release rate after
inoculation on treated biochar. FIG. 25 illustrates release rate
data verse total pore volume data for both coconut shell and pine
based treated biochars inoculated with a releasable bacteria. As
illustrated in FIG. 25, the data was plotted in a graph, and
clearly, shows that as pore volume increases so does the release
rate.
[0217] 5. Exterior and Interior Surface Geometry
[0218] Two important properties of microbial carriers are: (i)
their ability to release microbes from their surfaces and (ii)
their ability to immobilize or stabilize microbes on their
surfaces. Depending on the final application or use of the carrier,
one or both of these properties may be desired. For example, for
carriers designed to quickly release a microbe into a targeted
domain such as a lake, river, or other waterway, the release
characteristics of the material are paramount. For other
applications, such as applications of certain symbiotic microbes in
agriculture, rapid release may be undesirable, rather it may be
important to sustain the microbes within the porosity of the
material until plant tissue, such as root biomass, is nearby to
provide nutrition for the microbes in question. The surface and
pore geometry of the material used as a carrier can be critical to
determine this behavior. For example, material with generally
smooth, uniform surfaces will typically release many microbes much
more effectively, while material with more rugged, varied, tortuous
pore surfaces and geometry will typically retain and immobilize
microbes more effectively. The biomass used in the production of
the final material is one of the most important factors in surface
geometry. However, even this quality can be altered through
treatment. Specifically, smooth surfaces may be etched by
implementing the treatment and infusion processes previously
disclosed with strong acids, rendering them rougher. Conversely,
rough surfaces may be treated with either organic or inorganic
compounds to coat and remove contour. Mechanical means may also be
used to affect changes in particle geometry. Many forms of charred
material have relatively low crush strength and are relatively
brittle. The method used to grind, or size particles can have a
large impact on the geometry of the final particles. For example,
particles milled using a ball mill or other type of grinding
technology will typically have a smoother exterior geometry after
the milling is complete and may lose a good amount of their
porosity through the simple mechanical crushing of pores. However,
particles sized using ultrasonic vibrations or even simple physical
vibrations to shatter, rather than crush larger particles into
smaller ones, will typically retain their geometry, or sometimes
result in smaller particles with more rugged geometries than the
particles at the beginning. It should be apparent to one skilled in
the art that there are various mechanical mechanisms available to
effect these changes, but the resulting particles can be tailored
to meet a particular microbial release or immobilization
outcome.
[0219] 6. Particle Size and Distribution
[0220] It is well known that the particle size and particle size
distribution of a material has a key impact on its formulation as a
microbial carrier. In many cases, these factors are very different
for porous carbonaceous materials than they are for other common
microbial carriers. In standard carriers, typically the reduction
of particle size is a method used to increase surface area, and
thus the area available to support, immobilize, and carry microbes.
However, in porous materials, specifically materials with a large
volume of usable interior porosity, sometimes a reduction in
particle size does not cause a large increase in the usable surface
area specifically because the interior surfaces of the material
were already exposed, and reducing the size of the particle does
not change that fact. This leads to a somewhat counterintuitive
behavior in some cases in which the reduction of the particle size
of a porous material actually degrades its performance as a
microbial carrier, due to the phenomena that surfaces that were
once sheltered inside the material are exposed as exterior surfaces
when the material is split or crushed, making the material less
desirable as a habitat for microbes that require shelter from the
surrounding environment. Additionally, at times the actual
distribution of particle sizes can be a key factor in performance.
As a simple example, imagine an aggregated material which consists
of only two particle sizes: 1 mm and 1 .mu.m. Furthermore, imagine
that 50% of the mass of the aggregate resided in the 1 mm particles
with the remainder in the 1 .mu.m particles. Lastly, imagine that
the 1 mm particles were porous carbonaceous particles with an
average pore size of approximately 50 .mu.m. It should be clear
that if this aggregate was placed in a container and agitated, that
a good portion of the 1 .mu.m particles would end up inhabiting the
pore volume of the 1 mm particles, impacting their usability. In
fact, this is the behavior that we see in practice. Therefore, for
certain microbial applications, it is desirable to remove extremely
small particles, often referred to as fines, from the aggregate.
This has the additional benefit of reducing dust during
application, which is particularly important in aerial
applications, and reducing the level of surface runoff for
applications in water, which also is important in certain microbial
applications. The small particles may be removed through several
methods such as sieving, blowing or aerodynamic removal, separation
with either stationary or moving liquids (hydrostatic or
hydrodynamic separation) of various viscosities, temperatures, flow
rates, etc. However, at times, having a mixture of smaller and
larger particles can be desirable. The most common cases are when
communities of microbes are to be deployed, or the aggregate is to
remain generally intact for a period of time (fermentation
applications, long term storage applications, or preparation for
other formulation uses such as palletization), in which case, the
interparticle void space is also an important factor and can be
optimized for a particular microbe or set of microbes by providing
a range of particle sizes and geometries.
[0221] 7. Nutrient Exchange
[0222] The ability of a material to hold or exchange nutrients is
an incredibly important characteristic, not only for microbial, but
also for general agricultural applications. There are two primary
mechanisms that porous carbonaceous materials can exchange
nutrients: (i) sorption or retention of the nutrients on the
interior and exterior surfaces of the material, and (ii) retention
of the nutrients either in suspension or solution in liquid or
gasses residing in the pore volume of the material. Both mechanisms
are very useful, but also very different in function. Surface
sorption or retention is driven by two main properties, among
others: (i) ion exchange capacity of the material and. (ii)
reactivity or electrical charge of compounds present on or coating
the surfaces of the material. Retention of nutrients in solution or
suspension are impacted by other, different characteristics of the
material, such as hydrophilicity, oil sorption capacity, usable
pore volume and pore size distribution, and interior pore geometry
and tortuosity. The surface retention of nutrients can be targeted
by selecting the feedstock biomass (some materials render a char
after pyrolysis with vastly differing ionic exchange capacities
(CEC and AEC) than others). It can also be impacted by adjusting
pyrolysis conditions. Higher pyrolysis temperatures tend to reduce
CEC and nutrient adsorption capability. See Gai, Xiapu et al.
"Effects of Feedstock and Pyrolysis Temperature on Biochar
Adsorption of Ammonium and Nitrate." Ed. Jonathan A. Coles. PLoS
ONE 9.12 (2014): e113888. PMC. Web. 19 Nov. 2016. In addition, the
surface retention of nutrients can be impacted by treating the
surfaces of the material with substances targeted towards adjusting
the ionic exchange characteristics. For example, using the
previously disclosed treatment methods to infuse H.sub.2O.sub.2
into the pores of the carbonaceous material and then evaporating
the liquid can increase the cationic exchange properties of the
material.
[0223] Furthermore, another way to exchange nutrients more
efficiently is to use the pore volume rather than, or in addition
to, the pore surfaces--namely keeping the nutrients in solution or
liquid or gaseous form and placing them in the volume of the pores
rather than attempting to sorb them on the surfaces of the
material. This can be an incredibly useful technique not only for
plant life and soil health, but also for microbes. The food sources
can vary from simple to complex such as glucose, molasses, yeast
extract, kelp meal, or bacteria media (e.g. MacConkey, Tryptic Soy,
Luria-Bertani). When using the pore volume to exchange nutrients in
this way, it should be clear that a wide variety of nutrients may
be used, and targeted combinations of pore volume, size, and
nutrition can be produced to assist in the delivery, establishment,
or successful colonization of targeted microorganisms or groups of
microorganisms. It should be clear by this point that merely
immersing the biochar or porous carbonaceous material in a liquid
nutrient broth may be partially effective in filling the pore
volume or coating the pore surfaces with these nutrients and should
be considered within the scope of this invention, however using the
treatment techniques outlined in this and related disclosures is
much more effective at both coating the surfaces and infusing
nutrition into the pore volume of the material itself. Since many
microbes rely on liquid for mobility, placing liquid into the pore
volume of the material is in many cases a prerequisite for
successfully infusing, carrying, or delivering microbes.
[0224] 8. Usable Carbon or Energy Sources
[0225] Related to the ability to improve nutrient exchange is the
ability to treat the pore volume, pore surfaces, exterior surfaces,
or any combination of these with not only custom broths or growth
media, but also other forms of carbon known to be beneficial to
microbes and plant life. Some examples of this are carbohydrates
(simple and complex), humic substances, plant macro and
micronutrients such as nitrogen (in many forms, such as ammonium
and nitrates), phosphorous, potassium, iron, magnesium, calcium,
and sulfur and trace elements such as manganese, cobalt, zinc,
copper, molybdenum. These nutrients may either be infused in liquid
or gaseous form, or even as a suspended solid in liquid. The liquid
may be left in the pores, or may be removed. If removed through
evaporation, nutrients in solution or suspended solids may be left
behind, while if removed by mechanical or physical means, a portion
of the liquid may be left behind as well as some solids. It should
be noted that the various forms of removal have differing
advantages and disadvantages and that many energy sources may be
added either at the same time or in sequence, with one, or many,
removal steps in between treatment or infusion steps.
[0226] 9. Toxic Materials or Compounds
[0227] The selective addition or removal of materials or substances
known to be toxic to a certain microbe or lifeform is a key step in
preparation of biochar for use as a microbial habitat or carrier.
It has been shown, that through treatment, potentially toxic
compounds can be removed with much greater effectiveness than
through simple pyrolysis alone. Some examples of the potentially
deleterious compounds that may be removed are: volatile organic
compounds (VOCs), monoaromatics, polycyclic aromatic hydrocarbons
(PAHs), heavy metals, and chlorinated compounds (e.g. dioxins and
furans). A proven approach to remove these substances is to wash
the exterior surfaces with and/or rapidly infuse a solvent into the
pore volume of the material targeted to remove these substances.
Following the infusion with either mechanical extraction, drying,
or other methods to remove the solvent laden with the substances in
question, from the pores and interparticle, spaces is a desirable,
but not strictly necessary step to further reduce the levels of
toxicity. For example, the following data shows removal of dioxins
using the treatment process of the present invention.
TABLE-US-00007 Raw coconut Treated coconut Raw pine Treated pine
shell biochar shell biochar biochar biochar TEQ ng/kg 0.7 0.4 9.6
0.4 (method 8290A)
[0228] Another approach for some toxic compounds (benzene as one
example) is, rather than removing the compounds in question, to
react them in place with other compounds to neutralize the
toxicant. This approach can be used either with washing, or forced
assisted infusion, and in these cases a removal step is less
necessary although it still can be used to prepare the material for
another, subsequent phase of treatment.
[0229] Much attention is given to the removal of toxic compounds,
but it should be also be noted that at times, it can be extremely
beneficial to actually add or treat the material with toxic
compounds. A primary example of this is sterilization, or
preparation for selective infusion. Even after pyrolysis, residual
biological life has been found to potentially establish itself in
biochars given the right conditions. Treating, washing, or infusing
the material with antiseptics such as methanol, ethanol, or other
antibacterial or antiviral substances can be a key step in removing
contamination and preparing the material for use in microbial
applications. A variation on this approach is to infuse, treat, or
wash the material with a selectively toxic compound, such as a
targeted antibiotic or pharmaceutical targeted towards interrupting
the lifecycle of a specific set of microorganisms or organisms,
thereby giving other microbes, either through infusion or merely
contact in situ the opportunity to establish. Some examples of this
treatment would be the use of antifungals such as cycloheximide to
suppress fungal growth and provide an environment more well suited
toward the establishment of bacteria. As has been stated
previously, the methods may be used alone, or in combination with
one another. Specifically, a toxic compound such as ethanol, may be
infused, removed, and then steps may be taken to remove other toxic
compounds, followed by steps to add carbon sources or growth
media.
[0230] 10. Surface Structures/Crystals/Tortuosity
[0231] The physical surface and pore structure of the material is
critically important to its suitability as a microbial habitat.
There are many factors that contribute to the surface structure of
the material. The most notable of these factors is the biomass used
to produce the carbonaceous material the cellular structure of the
biomass dictates the basic shape of many of the pores. For example,
pyrolyzed coconut shells typically have less surface area, and a
more diverse distribution of pore sizes than pyrolyzed pine wood,
which, when pyrolyzed at the same temperature, has greater surface
area, but a more uniform (less diverse) pore size distribution.
Tortuosity, or the amount of curvature in a given path through a
selected pore volume is also an extremely important characteristic
of engineered porous carbonaceous materials.
[0232] FIG. 26 shows the total fungi/bacteria ratio for two
biochars derived from different biochar starting materials, e.g.,
feedstocks. Each biochar was loaded with different levels of
moisture, and the total fungi/bacteria ratio was monitored during
the first week. Biochar A 2301 showed a constant total
fungi/bacteria ratio of 0.08 across moisture levels range 5000 ng
from 15% to 40%, while Biochar B 2302 showed a constant total
fungi/bacteria ratio of 0.50 for moisture levels ranging from 30%
to 40%. It is theorized that, a fungi/bacteria ratio between 0.05
and 0.60 is an effective prescription for a stable biochar
composition. This composition allows a commercially viable product,
which has sufficient shelf life that it can be delivered to storage
houses waiting for the proper planting window.
[0233] It is theorized that the difference in the observed total
fungi/total bacteria ratios of may also be explainable by the
structures of the biochars. Biochar's having an open pore
structure, e.g., more interconnected pores, promotes more bacteria
formation; while closed pores, e.g., relatively non-connected
nature of the pores, tends to promote fungi formation. Biochars
with differing microbial communities may be beneficial for specific
applications in commercial agriculture. Thus, custom or tailored
loading of the microbial population may be a desired implementation
of the present invention.
[0234] For example, as shown in FIGS. 27a, 27b and 27c, Biochar A
2701 shows that it has a greater population of, i.e., is inhabited
by, more gram negative, gram positive and actinomycetes than
Biochar B 2702. Thus, for example, Biochar A would be more
applicable for use with certain agricultural crops in which Plant
Growth Promoting Bacteria (PGPB) species in the actinomycetes, gram
(-) pseudomonas, and bacillus groups are used for nutrient
utilization and uptake.
[0235] It should be noted that both pyrolysis and post-treatment
can be used to further modify the shape of these pores and
structures. Pyrolyzing at higher temperatures, injecting select
gasses or liquids during pyrolysis, or both typically will increase
the pore volume and surface area of the material in question. Steam
is the most readily available gas to cause this effect, but
hydrogen sulfide, carbon dioxide, carbon monoxide, as well as other
reactive gasses can be used. Prior art has clearly shown that the
surface area of a biochar changes based on feedstock and pyrolysis
temperature. Post treatment focused on a forced infusion of a
strong acid, or other reactive substance into the pore space of the
carbonaceous material can also be used to modify the pore size and
pore volume of material by removing or breaking down the carbon
matrix which forms the structure of the biochar, or other porous
carbonaceous material. Acid etching or infusion can also be used to
make smoother surfaces rougher. Rough surfaces can be very useful
in the attachment and immobilization of microbes. Smooth surfaces
can be useful for the easy release of carried microbes. Coating the
surface area with materials such as starches is a technique to make
rough surfaces smoother. Ultrasound, with or without a transmission
media (gel, liquid, oil, or other) can also be used to rupture
interpose divisions and create more pore space. Flash gasification
either at atmospheric pressure, or under negative or positive
pressure, of liquid infused into the pores by the methods
previously disclosed can also be used to crack, disrupt, or
fracture solid material separating adjacent pores.
[0236] While much attention is given to modifying the pore
structure by removing carbonaceous material, it should be noted
that the pore structure can also be modified by the coating, forced
infusion, and/or addition of materials which will bond to the
carbon and consume pore volume, smooth surfaces, add tortuosity,
change the exterior surfaces, or all of these. In the most simple
form, it should be clear that materials may be added to coat
surfaces or fill pore volume either through forced infusion, simple
contact, or other means. However, if the material is infused or
even simply contacted with a super saturated solution of a
substance that will crystallize, such as sucrose, sodium chloride,
or other common or uncommon substances known to form crystals. It
should be noted that the crystals or substances used to create them
do not need to be water soluble, and in fact in many cases it is
desirable if they are not. The crystals may also be composed of
nutrients or substances which may be beneficial to microbial or
plant life. Examples of this are sucrose and monoammonium
phosphate, both known for their ability to easily crystallize and
be beneficial for microbial and plant life respectively. By adding
material or even growing crystals on the carbon, a hybrid material
is formed which can have many properties that are exceptionally
useful for the delivery and establishment of microbial systems.
Crystallization is also way to add tortuosity to a carbonaceous
material and typically is much more effective in this aspect than
coating with solids alone.
[0237] 11. Compatibility with Biofilm Formation
[0238] Biofilms can be an important factor in the survival of a
microbe in extreme or challenging conditions. Bacterial communities
can shift their morphology to increase nutritional access and
decrease predation. One such modification is that the bacteria may
attach to surfaces, such as those found in biochar, in a densely
compacted community. In this compacted form, they may form an
extracellular polymeric substance (EPS) matrix called a biofilm.
These communities can contain hundreds of different species which
find shelter under the protective EPS coating from predatory
protozoa, pathogens, contaminants, and other environmental
stressors. In some cases, usually related to public health or
healthcare, biofilms are undesirable as they typically allow
pathogenic microbes to survive exposure to antiseptics,
antibiotics, predatory microbes such as protozoa, or other agents
which may eliminate them or negatively impact their prospects for
survival. But in agricultural settings, encouraging target biofilm
establishment could lead to improved microbe survival and thus
improved agricultural or crop benefits.
[0239] As outlined in the article titled The Effect of
Environmental Conditions on Biofilm Formation of Burkholderia
psudomallei Clinical Isolates, it can be seen that certain bacteria
require certain environmental factors, among them surface pH, for
the creation of biofilms. See Ramli, et al., The Effect of
Environmental Conditions on Biofilm Formation of Burkholderia
psudomallei Clinical Isolates (Sep. 6, 2012)
(http://dx.doi.org/10.1371/journal.pone.0044104). It is believed
that other surface characteristics (rugged vs. smooth surfaces,
surface charge, and more), along with moisture levels and relative
humidity also play a large role in biofilm formation.
[0240] But for certain microbes requiring deployment into
environments known to present survival challenges, optimizing a
delivery material to encourage the formation of these protective
biofilms can provide the targeted microbes with a significant
advantage. Also, many vegetable and short cycle row crops such as
tomatoes, lettuce, and celery form mutualistic relationships with
bacteria that lead to the formation of biofilms on root hairs that
function not only in nutrient uptake but also in plant pathogen
resistance.
[0241] As outlined in previous disclosure, treatment of raw biochar
can be used to adjust the surface pH to a level suitable for
biofilm formation. Similarly, adjusting the humidity by selectively
leaving a measured or controlled amount of water resident in the
pore volume of the material can also provide benefit. Lastly, the
techniques outlines for modifying the physical surface properties
of the material either by smoothing or roughening, can be key
factors also.
[0242] It should be clear that these factors can also be reversed
to create an environment that is unsuitable for biofilm formation
in applications where the formation of biofilms on the carrier is
not desirable--e.g. delivery or applications where quick release of
microbes from the carrier is important.
[0243] 12. Surface Charge
[0244] The surface charge of a porous carbonaceous material can be
crucially important in the association and establishment of
targeted microbes with or on the material. For example, most
bacteria have a net negative surface charge and in certain
conditions a specific bacterium may favor attachment to positively
charged surfaces. In some biological applications, this attachment
may be preferred, in others, attachment may not be preferred.
However, modifying the surface charge of the material is clearly a
way to impact the suitability for attachment of certain microbes.
There are many ways in which the surface charge of a carbonaceous
material may be changed or modified. One way to accomplish this is
by treating the surface area of the material with a solution
containing a metal, such as Mn, Zn, Fe, or Ca. This can be
performed either by doping the material with these metals prior to
or during pyrolysis, or more preferably, by using a forced infusion
or treatment technique after pyrolysis to deposit these substances
on the interior and/or exterior surfaces of the carbonaceous
material. By controlling the amount and or types of substances
infused, the surface charge of the material can be modified by
encouraging loading of O.sub.2.sup.- or other anions, or
conversely, N.sup.+, NH.sub.2.sup.+, or other cations. This
modification of surface charge can have a profound impact on the
ability of certain microorganism to be immobilized on the interior
and exterior surfaces of the material.
[0245] Another application of surface charge can be found by
temporarily charging the carbonaceous material during inoculation
with microbes. Carbon is used as a cathode or anode in many
industrial applications. Because of its unique electrical
properties, carbon, or more specifically porous carbonaceous
materials, may be given a temporary surface charge by the
application of a difference in electrical potential. One
application of this mechanism is to create a temporarily positively
charged surface to encourage microbial attachment. Then, while the
charge is maintained, allowing the microbes to attach themselves to
and colonize the carrier. Once the colonization is complete, the
charge can be released and the carrier, laden with microbes can
either be deployed as is, or can undergo further treatment to
stabilize the microbes such as lyophilization, or freeze
drying.
[0246] 13. Enzyme Activity
[0247] For some types of microbes, enzyme activity, or the presence
of certain enzymes is every bit as important as the availability of
energy or nutrition. Enzymes can be critical in the ability of
microbes to metabolize nutrition, which in turn can be a key
element of reproduction, survival, and effective deployment. There
are six main types of enzymes: hydrolases, isomerases, ligases,
lyases, oxidoreductases, and transferases. These enzymes can be
important in microbial applications. Through treatment or even
simple contact, enzymes, like nutrients and energy sources, can be
deposited on the surfaces or within the pore volume of porous
carbonaceous materials, either as solids, or in
solution/suspension, ensuring the enzymes are not degraded through
the process. However, forced infusion of enzymes through the
treatment processes previously outlined allows for much greater
storage capacity and much greater levels of contact with the
interior surfaces of the biochar, and as such, is preferable to
simple contact. In some cases, the carbonaceous material can be
used to deliver enzymes alone into an environment where both a
habitat and enzymes are needed to promote or encourage the growth
of certain indigenous microbes.
[0248] Another important aspect of enzyme activity is that some
bacteria make extra-cellular enzymes which could be bound by the
biochar or either reduce or even stop biochemical reactions. Thus,
in certain situations when application is appropriate the
carbonaceous material can be used to inhibit or make certain
enzymes ineffective. For example, if the biochar is being used as a
carrier for food or certain chemicals that are vulnerable to
breakdown by enzymatic degradation and these specific enzymes would
be bound by the biochar, then using the carbonaceous material as
the carrier would provide for greater shelf-life and viability of
the product versus traditional carriers.
[0249] 14. Sterilization
[0250] In many cases, it is desirable to remove potential unwanted
microbes from the surfaces and pore volume of the material through
sterilization. At outlined above, infusion with antiseptics or
antibiotics are a way to accomplish this. Boiling, or more
preferably, forced infusion of steam is also a technique that can
be used to remove resident microbial life. Heating to a temperature
above 100 degrees C., and preferably between 100 and 150 degrees C.
is also effective for removing some microbial life. Heating may be
required for ideally 30 minutes or more, depending on volume,
method, and extent (temperature, radiation). Autoclaving can also
be used 30 minutes, 121 degrees C., 20 psig. For applications
requiring a high level of sterility, gamma irradiation can be used,
with dosages adjusted for the level of sterility needed in ranges
of 5 to 10 kGy or even 50 to 100 kGy or even higher dosage levels.
For all sterilization methods, the extent of treatment required
will depend on the volume of material and the required level of
sterilization. In general, sterilization, using heat, should be
done for at least 30 minutes, but should be adjusted as needed.
[0251] At this point, it should be clear that all of these
properties can be controlled and modified to create a treated,
controlled biochar that is suitable for use as a microbial carrier,
delivery system, habitat, fermentation substrate, or environmental
(soil, water or other) enhancement. By controlling these properties
and producing a material matched to the application and the
microbe(s) in question, effectiveness can be dramatically improved
over both traditional biological carriers, and many forms of raw,
untreated, uncontrolled biochar. Furthermore, varying materials,
with varying properties, may be aggregated to provide delivery
systems or habitats targeted towards consortia, communities, or
groups of microbes.
[0252] E. Inoculating, Applying, or Immobilizing the Microbes on
the Biochar
[0253] Typically, the prior art teaches either placing biochar on
soils alone or combining the biochar with compost and using this
mixture as a soil amendment. The nature of the microbial population
in this compost mixture is poorly disclosed by the prior art. Thus
using more targeted methods to get the desired microbes into the
suitable habitat created by the raw biochar, or more preferably
treated or controlled biochar is desired. The following are some
but not all, methods and systems that can be used to inoculate,
deploy, or otherwise associate microbial life with a treated or
untreated biochar:
[0254] 1. Co-Deployment
[0255] This method focuses on deploying the microbes at the same
time as the biochar. This can be done either by deploying the
biochar into the environment first, followed by microbes or by
reversing the order, or even deploying the two components
simultaneously. An example of this would be the deployment of a
commercial brady rhizobium inoculant simultaneously with the
introduction of a treated biochar into the soil media. The system
here is the combination use of a biochar and microbes in the
environment, and more preferably a char treated to have suitable
properties for a target microbe or group of microbes which it is
used with in a targeted application for a specified purpose, for
example a symbiotic crop of said microbe(s).
[0256] In one experiment, various biochar feedstocks with various
post-treatments were added to a soilless mix containing soybean
seeds that had been treated with a commercial microbial product
containing bradyrhizobium japonicum, and compared to both a control
with microbe inoculant and one without. Some of the treated
biochars co-deployed with the inoculant increased seed germination
rates, one by 29%. Others increased nodulation measured at 10
weeks, one more than doubled the number of nodules. The use of the
microbial inoculant increased shoot biomass in all treatments. FIG.
28 is a chart comparing shoot biomass when the biochar added to a
soilless mix containing soybean seeds is treated with microbial
product containing bradyrhizobium japonicum, and when it is
untreated. As illustrated in FIG. 28, shoot biomass increased with
the biochar was treated.
[0257] FIG. 29 shows the comparison of root biomass in a microbial
inoculated environment versus one without inoculation. As
illustrated in FIG. 29, when inoculated, root biomass decreased
with the inoculant alone yet increased with the use of all the
treated biochars with or without inoculant.
[0258] In addition leaf tissue analysis was done which showed some
of the treated biochars co-deployed with the rhizobial inoculant
showed a significant increase in nitrogen uptake. FIG. 30 is a
chart comparing the nitrogen levels when the biochar is inoculated
with the rhizobial inoculant verses when it is not inoculated.
Statistical significance in the chart in FIG. 30 is marked with a
star. In all cases, nitrogen levels increase with inoculation.
[0259] As outlined in these results, the addition of a treated
biochar suitable for co-deployment with this particular microbe
increased nodulation, increased nitrogen fixation/availability, and
resulted in substantially increased root mass. It should be noted
that to demonstrate the differing performance of varying
formulations, two formulations were tested, each showing different
interactions with the microbe in question, along with significant
variations in performance. This is just one example to demonstrate
the invention of how the specific combination of biochar feedstock,
biochar treatment, co-deployed microbe, and application (this case
plant species) can lead to improved microbial effectiveness and
thus improved results (this case plant vigor), versus no treatment,
applying the microbe alone, or applying the biochar alone. Another
example of co-deployment benefit could be using a biochar that has
strong absorption properties in combination with fertilizer (or
infused with fertilizer) and microbes in an agricultural setting.
The biochar properties that help retain and then slowly release
nutrients and ions will also help the targeted microbe population
to establish and grow without being impacted by the high levels of
fertilizer salts or nutrients which can often impede and sometimes
kill the microbes being deployed.
[0260] 2. Basic Inoculation
[0261] A more advanced method of inoculation centers on mixing the
microbe or microbes in question with the treated or untreated
biochar before deployment. In some cases, the biochar in question
can be treated, produced, or controlled to assist with this
deployment, making this case slightly different than merely
inoculating a microbe on untreated biochar. In one form, microbes
suspended in liquid (either water, growth media, or other liquids)
are deposited on the biochar and mixed together until both
materials are well integrated and then the material is deployed as
a granular solid. It has been shown that materials that have been
treated to be more hydrophilic typically accept this inoculation
more readily than hydrophobic materials--demonstrating yet another
way in which the treatment of biochar can enhance performance. In
another form of basic inoculation, the biochar is delivered in
suspension in the liquid also carrying the microbes. This
biochar/liquid/microbe slurry is then deployed as a liquid. In this
form, sizing the biochar particles in such a way that their surface
properties and porosity is maintained is a key element of
effectiveness. Additionally, ensuring that the pores are treated to
allow easy association of both liquid and microbes with the
surfaces of the biochar is important. An example of a basic
inoculation method of biochar for a bacteria in lab scale is as
follows: [0262] 1) Isolate Pseudomonas protegens on a plate with
1.5% w/v Tryptic Soy Broth solidified with 1.5% w/v agar and
incubate at 30.degree. C. for 12 h [0263] 2) Take an isolated
colony of Pseudomonas protegens and grow up in a 1.5% w/v TSB
solution (90 ml) along with 10 g sterile biochar (sterilized at 110
C in small batches for 15-20 min) and combine both in a sterile 250
ml Erlenmeyer flask [0264] 3) Shake contents of flask at 150 rpm at
30.degree. C. for 12 h, or greater [0265] 4) Transfer contents of
flask into a sterilized ultracentrifuge tube (250 ml) and spin at
10,000.times.g for 10 min [0266] 5) Carefully remove supernatant
liquid fraction by filtering through a Whatman No 4 filter with a
vacuum filtration system to separate out the bulk liquid from
biochar. After basic inoculation, the material and the microbes may
be deployed immediately, stored for future use, or stabilized using
technology such as lyophilization.
[0267] 3. Assisted Inoculation
[0268] Another form of inoculation, which appears to have greater
efficacy with some microbial systems, is assisted inoculation.
Assisted inoculation involves providing mechanical, chemical, or
biological assistance to move the targeted microbe either into the
pore volume of the carrier or onto interior surfaces of the
material that normally may not be accessible. Realizing that many
microbes require liquid, and preferably water, for mobility, the
most straightforward method of assisted inoculation requires
infiltrating the pore volume of the material with water prior to
contact with the targeted microbes. This water infusion can be done
using the treatment methods described previously in this
disclosure. It has been shown that, with certain microbes, making
this change alone will have a positive impact on the ability of
microbes to associate with and infiltrate the material. In one
experiment, it was shown that water infusion improved release rate
on both a treated pine biochar with granular particles and with a
coconut biochar powder. FIG. 31 illustrates the three-day release
rates of water infused biochar compared to other types of biochar.
As illustrated, results vary depending upon the biomass.
[0269] Changes can also be made in the media to reduce surface
tension and increase flowability through the addition of a
surfactant to the water, either into the liquid used to carry the
microbes, or into the pores of the material itself, through simple
contact, or preferably forced infusion.
[0270] Additionally, the microbes themselves may be assisted into
the pores using the treatment techniques previously outlined. Care
needs to be taken to match the microbe to the technique used, but
many microbes are capable of surviving vacuum infiltration if
performed at relatively gentle, lower pressure differentials
(+/-10% of standard temperature and pressure). Some microbes, and
many spores however are capable of surviving vacuum infiltration
even at relatively large pressure differentials (+/-50, 75, or even
90 or 95% or more variation from standard temperature and
pressure). When this technique is used, a liquid mixture is
constructed containing both liquid to be infused and the microbe or
microbes in question. The liquid is then used as the "infiltrant"
outlined in previous disclosure related to placing liquid into the
pore volume of the material. The final material, infiltrated with
microbes, may then be heated to incubate the microbes, cooled to
slow development of the microbes or stabilize the microbes, or have
other techniques applied such as lyophilization. The material may
then be delivered in solid granular form, powdered, further sized
downward by grinding or milling, upward by agglomerating,
aggregating, or bonding, or suspended in a liquid carrier. A clear
advantage to this assisted infusion approach is that the material
can be processed or handled after inoculation with more microbial
stability because the targeted microbes are inhabiting the interior
pore volume of the material and are less prone to degradation due
to contact with exterior surfaces, or other direct physical or
environmental contact. This method may be applied repeatedly, with
one or more microbes, and one to many moisture removal steps. It
may also be combined with the other inoculation methods disclosed
here either in whole or in part.
[0271] FIGS. 32a, 32b and 32c show scanning electron microscopy
(SEM) images of raw biochar compared to ones that have been
processed by being infused under vacuum with bio-extract containing
different microbial species.
[0272] FIG. 32a is a SEM (10 KV.times.3.00K 10.0 .mu.m) of pore
morphology of raw biochar. FIG. 32b is a SEM (10 KV.times.3.00K
10.0 .mu.m) of pore morphology of raw biochar of FIG. 32a after it
has been infused with microbial species. FIG. 32c is a SEM (10
KV.times.3.00K 10.0 .mu.m) of a pore morphology of another example
of raw biochar of FIG. 32a after it has been infused with microbial
species. The images confirm the ability to incorporate different
microbes into the pores of biochar by treatment. In turn, these
beneficial microbes can interact with and enhance the performance
of the environment they are deployed into, for example the plants'
root systems when the inoculated biochar is mixed with the soil in
the root zone.
[0273] Compared to a biochar that has immersed in a compost tea,
which may have a relatively short, e.g., a few days for the life of
the microbes, the impregnated populations of examples of the
present treated biochars, are stable over substantially longer
periods of time, e.g., at least an 8 week period and in some cases
1 year or more as measured by PLFA (Phospholipid-derived fatty
acids) analysis. PLFA analysis extracts the fatty acid side chains
of phospholipid bilayers and measures the quantity of these
biomarkers using GC-MS. An estimate of the microbial community
population can thus be determined through PLFA analysis. The
microbial activity may also be inferred through PLFA analysis by
monitoring the transformation of specific fatty acids. Thus, the
impregnation of the biochar with a microbial population provides
for extended life of the microbes by at least 5.times., 10.times.,
or more over simple contact or immersion. In fact, some microbes
may be better suited to surfactant infiltration versus vacuum
infiltration and vice versa and this may impact the shelf life,
penetration, viability, or other characteristics of the
microbes.
[0274] As used herein, unless stated otherwise, the stable shelf
life of an example of a biochar product having a microbial
population is the period of time over which the product can be
stored in a warehouse, e.g., dry environment, temperature between
40.degree. F.-90.degree. F., with a less than 50% decrease in
microbial population.
[0275] 4. Integrated Growth/Deployable Substrate
[0276] With many microbes, especially fungi, it can be helpful to
develop or "grow" the microbes on the material itself. With porous
materials, rather than mechanically or chemically assisting the
infiltration of the microbes, it can be beneficial to allow the
microbes themselves to inhabit the pore volume of the material
prior to deployment. In fact, with materials constructed to
effectively immobilize microbes, this can be the most efficient
technique to stabilize, store, and ultimately deploy the microbes
in question.
[0277] An example of this method involves preparing the biochar
material for the microbes, sometimes through thorough cleansing,
other times through addition of either enzymes or energy sources
needed by the microbe in question, preferably using the treatment
techniques described previously in this disclosure. Once the
material is prepared, the microbes are placed onto the material, or
infused into the material and then incubated for a period of time.
In the case of many microbial systems, the microbes themselves will
inhabit the material and form close affiliations with available
surfaces and pore volume. At this point, the material can be
deployed with the microbes actively attached and affiliated. With
many microbes, especially fungi, this is a preferred method of
deployment and shows many advantages over co-deployment, or basic
inoculation because of the tight integration of biological life
with the material itself.
[0278] An example of an integrated growth inoculation method of
biochar for a fungus in lab scale is as follows: [0279] 1) Make
petri dishes containing corn meal agar (17 g/L), glucose (10 g/L),
and yeast extract (1 g/L) [0280] 2) Inoculate plates with Sordaria
fimicola and incubate between 22-30 C for at least 1 day to produce
hyphae [0281] 3) Sterilize an inoculating loop and slice "plugs" of
the hyphae and agar generating cubes that are agar and hyphal mass
[0282] 4) Inoculate a sterile plate with a "plug" in the center of
the plate, around perimeter have sterile biochar [0283] 5) Incubate
plate for at least a day and remove biochar (that are now covered
with grown over hyphae)]
[0284] It should be noted that because of this effect, biochars,
and specifically treated biochars can also be extremely effective
substrates for solid state fermentation--particularly when growth
media or energy sources are added to the pore volume of the
material. So, once incubation is ongoing, the material can either
be removed, with the integrated microbes, and deployed, or it can
be stabilized for long term storage, or it can be left in situ and
used as a fermentation or growth substrate to develop or grow more
microbes--especially those that require a solid to propagate and
develop.
[0285] 5. Media and/or Enzyme Infiltration
[0286] As mentioned previously, growth media, energy sources,
enzymes, or other beneficial/necessary components for microbial
growth may be infused into the pore volume or coated onto the
surfaces of the material in question. This method can be combined
with any of the other inoculation techniques disclosed here. It has
been shown that with certain microbes and certain types of
material, inoculation with growth media or enzymes can significant
impact the effectiveness of the biochar material as a carrier.
[0287] 6. Habitat Pre-Establishment (Enhanced Rhizosphere)
[0288] There are certain microbes which, because of symbiotic
associations with host organisms, such as plants, prefer to develop
in the vicinity of the organism, such as the active root or other
plant tissue. An effective method for deploying these organisms can
be to develop and deploy the plant/microbe/habitat (biochar) system
together as a unit.
[0289] An example of this is germinating seed or transplanting a
seedling or developing juvenile plant in the presence of treated or
untreated biochar, and the targeted microbes. Biochar that has been
treated to encourage hydrophilicity and neutral pH typically allows
for easier affiliation of plant root tissue with the material. As
this affiliation occurs, a habitat for symbiotic organisms is
developed within the material itself due to the proximity of active
plant tissue to microbes reliant on the tissue for energy. As this
symbiosis continues, the number, activity, and colony size of the
targeted microbes will continue to grow. At this point, the plant
and biochar can be deployed together into the target environment,
acting as a pre-established habitat and carrying the microbes along
with them.
[0290] Another option is to develop and then remove the biochar
from the "incubation" system either by stripping the biochar
material from the symbiotic organism, such as the root mass, or by
sieving or sifting the media used to grow the plant. At this point,
the microbes can either be deployed directly or stabilized for
storage.
[0291] Thus, through more controlled inoculation of the biochar
particles, one can achieve a predetermined and controllable amount
of a microbial community, e.g., population, into the soil. This
integration of a microbial community with a biochar particle, and
biochar batches provides the ability to have controlled addition,
use and release of the microbes in the community. In agricultural
applications, this integration c a n further enhance, promote and
facilitate the growth of roots, e.g., micro-roots, in the biochar
pores, e.g., pore morphology, pore volume.
[0292] Other methods than those listed above exist for integrating
a microbial community with an untreated or previously infused
biochar particle. Different manners and methods would be preferred
depending on needs to minimize contamination, encourage biochar
pore colonization/infiltration, minimize labor and cost and
producing a uniform, or mostly uniform, product.
[0293] Other methods for integrating a microbial community with a
biochar particle may include, but are not be limited to the
following: while under vacuum, pulling the microbial solution
through a treated biochar bed that is resting on a membrane filter;
spraying a microbial solution on top of a treated biochar bed;
lyophilizing a microbial solution and then blending said freeze
dried solution with the treated biochar; again infusing, as defined
previously, the treated biochar with a microbial solution; adding
treated biochar to a growth medium, inoculating with the microbe,
and incubating to allow the microbe to grow in said biochar
containing medium; infusing, as defined previously, the biochar
with a food source and then introducing the substrate infused
biochar to a microbe and incubating to allow the microbes to grow;
blending commercially available strains in dry form with treated
biochar; adding the treated biochar to a microbial solution and
then centrifuging at a high speed, potentially with a density
gradient in order to promote the biochar to spin down with the
microbes; densely packing a column with treated biochar and then
gravity flowing a microbial solution through the column and
possibly repeating this multiple times; or adding the microbe to a
solution based binder that is well known to enter the treated
biochar pores and then adding said solution to the treated biochar.
In order to insure the proper microbial community the treated
biochar may need to be sterilized prior to these methods for
integrating a microbial community. All or parts of the above
manners and methods may be combined to create greater efficacy. In
addition, those skilled in the art will recognize that there may be
additional manners or methods of infusing biochars with microbials,
including those created by the combination of one or more of the
manners and methods listed above, without departing from the scope
of the present invention.
[0294] F. Using Microbial Inoculated Biochars
[0295] Thus, treated biochar can have a microbial community in its
pores (macro-, meso-, and combinations and variations of these), on
its pore surfaces, embedded in it, located on its surface, and
combinations and variations of these. The microbial community can
have several different types, e.g., species, of biologics, such as
different types of bacteria or fungi, or it may have only a single
type. For example, a preferred functional biochar, can have a
preferred range for bacterial population of from about 50-5000000
micrograms/g biochar; and for fungi, from about 5 to 500000
micrograms/g biochar. A primary purpose in agricultural settings,
among many purposes, in selecting the microbial population is
looking toward a population that will initiate a healthy soil,
e.g., one that is beneficial for, enhances or otherwise advance the
desired growth of plants under particular environmental conditions.
Two types of microbial infused biochars will be discussed further
for agricultural settings: bacteria and fungi. However, the
microbes may also be used in other applications, including but not
limited to animal health, either directly or through interactions
with other microbes in the animals' digestive tract and public
health applications, such as microbial larvicides (e.g. Bacillus
thuringiensis var. israelensis (Bti)) and Bacillus sphaericus used
to fight Malaria).
[0296] G. Bacteria Inoculated Biochars
[0297] PGPB include, for example, plant growth promoting
rhizobacteria, free-living and nodule-forming nitrogen fixing
bacteria, organic decomposers, nitrifying bacteria, phosphate
solubilizing bacteria, biocontrol agents, bioremediation agents,
archea, actinomycetes, thermophilic bacteria, purple sulfur
bacteria, cyanobacteria, and combinations and variations of
these.
[0298] PGPB may promote plant growth either by direct stimulation
such as iron chelation, phosphate solubilization, nitrogen fixation
and phytohormone production or by indirect stimulation, such as
suppression of plant pathogens and induction of resistance in host
plants against pathogens. In addition, some beneficial bacteria
produce enzymes (including chitinases, cellulases, -1,3 glucanases,
proteases, and lipases) that can lyse a portion of the cell walls
of many pathogenic fungi. PGPB that synthesize one or more of these
enzymes have been found to have biocontrol activity against a range
of pathogenic fungi including Botrytis cinerea, Sclerotium rolfsii,
Fusarium oxysporum, Phytophthora spp., Rhizoctonia solani, Pythium
ultimum.
[0299] Currently the most economic conventional solid carrier used
to deliver microbes is peat. A solid carrier allows for a
relatively long shelf life and a more direct application to a
plant's root system compared to a microbial liquid solution, which
would be sprayed directly.
[0300] Research has shown a substantial increase in PGPB growth and
distribution resulting from being infused in biochar. For example,
data resulting from research conducted to compare the effects upon
CO2 production (an indicator of bacterial growth) using peat and
biochars show the beneficial effects of using various biochars in
promoting PGPB growth. As illustrated in the left-hand chart in
FIG. 33, peat results in CO2 production of between approximately
10% and 30% (depending upon the grown medium), whereas biochars
result in CO2 production of approximately 48% and 80%. Replicated
experimental results using different biochars confirm CO2
production of approximately 30% to 70% (depending on the grown
medium), as compared to approximately 10% to 20% for the peat
control.
[0301] The method developed for determining this CO2 production as
an indicator of bacterial growth consists of the following. The
substrate, here biochar or peat, is sterilized by heating at 110 C
for 15 hours. A bacterial stock solution is then created, here
Tryptic Soy Broth was solidified with agar at 1.5% w/v in petri
plates to isolate the gram negative non-pathogenic organism
Escherichia coli ATCC 51813 (15 h growth at 37.degree. C.). Then an
isolated colony is captured with an inoculating loop and suspend in
10 ml sterile buffer (phosphate buffer saline or equivalent) to
create the bacterial stock solution. Lactose containing assays are
then used, here, test tubes that contain 13 ml of either Lauryl
Tryptose Broth (LTB) or Brilliant Green Broth (BGB) that also
contain a Durham tube. A negative control is generated by adding 10
.mu.L of sterile buffer to triplicate sets of LTB and BGB tubes. A
positive control is generated by adding 10 .mu.L of bacterial stock
solution to triplicate sets of LTB and BGB tubes. A negative
substrate is generated by adding 1.25 ml (.about.1% v/v) of sterile
substrate to triplicate sets of LTB and BGB tubes. A positive
substrate is generated by adding 1.25 ml (.about.1% v/v) of sterile
substrate and 10 .mu.L of bacterial stock solution to triplicate
sets of LTB and BGB tubes. The tubes of the four treatments are
then incubated statically in a test tube rack at 37.degree. C. for
at least 15 h. The tubes are then carefully observed and any gas
bubbles captured by the Durham tube within respective LTB or BGB
tubes are closely measured with a ruler. Small bubbles <0.2 mm
should not be considered. A continuous bubble as shown in
individual tubes in FIG. 34 are what are observed and quantified.
FIG. 34 is an example of carbon dioxide production captured as a
continuous gas bubble in BGB (left two tubes) and LTB (right two
tubes) growth medium. The percent carbon dioxide production is then
calculated by dividing the recorded bubble length by the total
Durham tube length and multiplying by 100.
[0302] Further tests were conducted using the Streptomyces lidicus
WYEC 108 bacterium found in one of the commercially available
products sold under the Actinovate brand. Actinovate products are
biofungicides that protect against many common foliar and
soil-borne diseases found in outdoor crops, greenhouses and
nurseries. The formulations are water-soluble.
[0303] FIG. 35 illustrates the effects upon the growth of
Streptomyces lidicus using conventional peat versus biochars. In
the test illustrated by the photograph on the left of FIG. 35, an
Actinovate powder was blended with peat, placed in an inoculated
media and incubated at 25.degree. C. The photograph shows the
distribution and density of white colonies after 3 days. In the
test illustrated by the photograph on the right of FIG. 35, an
Actinovate powder was blended with the treated biochar, placed in
an inoculated media and incubated at 25.degree. C. The photograph
also shows the distribution and density of white colonies after 3
days, the distribution and density of which are significantly
greater than those achieved with peat.
[0304] FIG. 36 further illustrates the improved growth of the
Actinovate bacterium using biochar versus peat. The left photograph
shows only limited and restricted growth away from the peat
carrier. The right photograph shows abundant growth of the
bacterium spread much farther out from the biochar carrier.
[0305] Another application of using biochar inoculated with
bacteria would be in the biofuel industry, where methanotroph
inoculated biochar could be used to create methanol. Methanotrophic
bacteria are proteobacteria with diverse respiration capabilities,
enzyme types, and carbon assimilation pathways. However,
Methylosinus trichosporium OB3b is one of the few methanotrophs
that can be manipulated by environmental conditioning to
exclusively produce methanol from methane. M. trichosporium OB3b is
one of the most well studied aerobic C.sub.1 degraders and can be
grown in either batch or continuous systems. As mentioned earlier,
the large pore volume and surface area of biochar is suitable for
bacterial colonization and should subsequently increase substrate
access to enzyme activation sites. To improve the conversion rate,
copper, nitrate, and phosphate should be included in the system.
The use of biochar as a support material for the aerobic
bioconversion of methane to methanol provides a pore distribution
suitable for both adsorptions of methane and impregnation with
bacteria. By providing biological and adsorptive functionality the
biochar can intensify the bacteria in the biochar and increases the
conversion rate.
[0306] In general, bacteria communicate via the distribution of
signaling molecules which trigger a variety of behaviors like
swarming (rapid surface colonization), nodulation (nitrogen
fixation), and virulence. Biochars can bind signaling molecules and
in particular it is believed can bind a major signaling molecule to
their surface. This binding ability can be dependent upon many
factors including on the pyrolysis temperature. This dependency on
pyrolysis temperature and other factors can be overcome, mitigated,
by the use of examples of the present vacuum infiltration
techniques. For example, a signaling molecule that is involved in
quorum sensing-multicellular-like cross-talk found in prokaryotes
can be bound to the surface of biochars. Concentration of biochars
required to bind the signaling molecule decreased as the surface
area of biochars increased. These signaling molecules may be added
to the surface of a biochar and may be used to manipulate the
behavior of the bacteria. An example of such a use would be to bind
the molecules which inhibit cell-to-cell communication and could be
useful in hindering plant pathogens; using techniques in the
present invention signaling molecules may be added to the surface
of a biochar to engineer specific responses from various naturally
occurring bacteria.
[0307] H. Fungi Inoculated Biochars
[0308] Beneficial fungi include, for example, saprotrophic fungi,
biocontrol fungi, ectomycorrhizae, endomycorrhizae, ericoid
mycorrhizae, and combinations and variations of these. It is
further theorized that, in general, biochars with greater fungal
development may be better suited for perennial crops such as
grapes, almonds, blueberries, and strawberries in which symbiotic
relationships with arbuscular mycorrhizal fungi (AMF) are favored
over PGPBs. The presence of high concentrations of AMF spores in
biochars can therefore rapidly promote fungal colonization of plant
root hairs leading to extensive mycelial development. Increased
plant root associations with mycelial filaments would consequently
increase nutrient and water uptake.
[0309] Mycorrhizal fungi, including but not limited to
Endomycorrhizae and Ectomycorrhizae, are known to be an important
component of soil life. The mutualistic association between the
fungi and the plant can be particularly helpful in improving plant
survivability in nutrient-poor soils, plant resistance to diseases,
e.g. microbial soil-borne pathogens, and plant resistance to
contaminated soils, e.g. soils with high metal concentrations.
Since mycorrhizal root systems significantly increase the absorbing
area of plant roots, introducing mycorrhizal fungi may also reduce
water and fertilizer requirements for plants.
[0310] Typically mycorrhizae are introduced into soil as a liquid
formulation or as a solid in powder or granular form and contain
dormant mycorrhizal spores and/or colonized root fragments. Often
the most economic and efficient method is to treat the seeds
themselves, but dealing with traditional liquid and powder
inoculums to coat the seed can be difficult. In accordance with the
present invention, inoculated biochar may be used to coat the seeds
by, for example, using a starch binder on the seeds and then
subjecting the seeds to inoculated biochar fines or powder. Another
method is by placing the mycorrhizae inoculum in the soil near the
seeding or established plant but is more costly and has delayed
response as the plants initial roots form without a mycorrhizal
system. This is because the dormant mycorrhizae are only activated
when they come close enough to living roots which exude a signaling
chemical. In addition if the phosphorus levels are high in the
soil, e.g. greater than 70 ppm, the dormant mycorrhizae will not be
activated until the phosphorus levels are reduced. Thus applying
inoculant with or near fertilizers with readily available
phosphorus levels can impede the desired mycorrhizal fungi growth.
A third option is to dip plant roots into an inoculant solution
prior to replanting, but this is costly as it is both labor and
time intensive and only applicable to transplanting.
[0311] If the colonization of mycorrhizae can be quickened and the
density of the mycorrhizae's hyphal network can be increased then
the beneficial results of mycorrhizal root systems, e.g. increased
growth, increased survivability, reduced water, and reduced
fertilizer needs, can be realized sooner. Prior art shows that
compost, compost teas, humates, and fish fertilizers can improve
microbial activities and in more recent studies have shown
physically combining arbuscular mycorrhizal fungi (AMF) inoculant
with raw biochar has resulted in additional plant yield compared to
each alone. See Hammer, et. al. Biochar Increases Arbuscular
Mycorrhizal Plant Growth Enhancement and Ameliorates Salinity
Stress, Applied Soil Ecology Vol 96, November 2015 (pg.
114-121).
[0312] An ideal carrier for the mycorrhizae would have moisture,
air, a neutral pH, a surface for fungi to attach, and a space for
the roots and fungi to meet. Thus a previously infused biochar
created by the method disclosed above would be a better carrier
than raw biochar alone. The infused biochar could be physically
mixed with a solid mycorrhizal fungi inoculant or sprayed with a
liquid mycorrhizal inoculant prior to or during application at
seeding or to established plants. Additionally, the infused biochar
and mycorrhizal fungi inoculant could be combined to form starter
cubes, similar to Organo-Cubes, rockwool, oasis cubes, and peat
pots.
[0313] The infused biochar could be further improved upon by
initially infusing or further infusing the biochar with
micronutrients for mycorrhizal fungi, for example but not limited
to humic acid, molasses, or sugar. The growth nutrient infused
biochar would further expedite the colonization of the mycorrhizal
fungi when physically combined with the inoculant and applied to
seeds or plants.
[0314] Another improvement to the infused biochar would be to
initially infuse or further infuse the biochar with the signaling
molecules of mycorrhizal fungi. The signaling molecule infused
biochar would further expedite the colonization of the mycorrhizal
fungi when physically combined with the inoculant and applied to
seeds or plants, as it would bring the mycorrhizae out of dormancy
quicker and thus establish the mycorrhizal root system quicker.
[0315] Another method for establishing and improving mycorrhizal
fungi colonies would be by growing mycorrhizae into the infused
biochar and then applying the mycorrhizal fungi inoculated biochar
to seeds or plants. Similar to a sand culture (Ojala and Jarrell
1980 http://jhbiotech.com/docs/Mycorrhizae-Article.pdf), a bed of
infused biochar is treated with a recycled inoculated nutrient
solution by passing it through the bed multiple times.
[0316] I. Batch Treatment/Bulk Production
[0317] As demonstrated above, the treatment processes described
above are particularly well suited for large scale production of
biochar. The processes and biochars of the present invention
provides a unique capability to select starting materials and
pyrolysis techniques solely on the basis of obtaining a particular
structure, e.g., pore size, density, pore volume, amount of open
pores, interconnectivity, tortuosity, etc. Thus, these starting
materials and processes can be selected without regard to adverse,
harmful, phytotoxic side effects that may come from the materials
and processes. This is possible, because the infiltration steps
have the capability of mitigating, removing or otherwise address
those adverse side effects. In this manner, a truly custom biochar
can be made, with any adverse side effects of the material
selection and pyrolysis process being mitigated in later processing
steps.
[0318] Further, the processes are capable of treating a large,
potentially variable, batch of biochar to provide the same,
generally uniform, predetermined customized characteristics for
which treatment was designed to achieve, e.g., pH adjustment.
Treatment can result in treated biochar batches in which 50% to 70%
to 80% to 99% of the biochar particles in the batch have same
modified or customized characteristic, e.g., deleterious pore
surface materials mitigated, pore surface modified to provide
beneficial surface, pore volume containing beneficial
additives.
[0319] Accordingly, the ability to produce large quantities of
biochar having a high level of consistency, predictability and
uniformity, provides numerous advantages in both large and small
agricultural applications, among other things. For example, the
ability to provide large quantities of biochar having predetermined
and generally uniform properties will find applications in large
scale agriculture applications. Thus, treated biochar batches from
about 100 lbs up to 50,000+ lbs and between may have treated
biochar particles with predetermined, uniform properties.
[0320] As the treated biochar batches are made up of individual
biochar particles, when referring to uniformity of such batches it
is understood that these batches are made up of tens and hundreds
of thousands of particles. Uniformity is thus based upon a sampling
and testing method that statistically establishes a level of
certainty that the particles in the batch have the desired
uniformity.
[0321] Thus, when referring to a treated batch of biochar as being
"completely uniform" or having "complete uniformity" it means that
at least about 99% of all particles in the batch have at least one
or more property or feature that is the same. Same being within
appropriately set tolerances for said property. When a treated
batch of biochar is referred to as "substantially uniform" or
having "substantial uniformity" it means that at least about 95% of
all particles in the batch have at least one or more property or
feature that is the same. When a treated batch of biochar is
referred to as "essentially uniform" or having "essential
uniformity" it means that at least about 80% of all particles in
the batch have at least one or more property or feature that is the
same. The batches can have less than 25%, 20% to 80%, and 80% or
more particles in the batch that have at least one or more property
or feature that is the same. Further, the batches can have less
than 25%, 20% to 80%, and 80% or more particles in the batch that
have at one, two, three, four, or all properties or features that
are the same.
[0322] J. Applications
[0323] Generally, treated biochar of the present inventions can be
used throughout the world, in numerous soil types, agricultural
applications, horticultural, large and small scale farming, organic
farming, and in a variety of soil management applications and
systems, and combinations and variations of these. In fact, this
particular solution provides the capability to custom-manufacture
biochar for a particular climate, environment, geographical area,
soil type, plant type, microbe type, or application by more
precisely controlling key characteristics.
[0324] Examples of these applications include for example, use in
acidic and highly weathered tropical field soils, use in temperate
soils of higher fertility, use in large commercial applications,
use for the production of large scale crops such as, soybean, corn,
sugarcane and rice, in forestry applications, for golf courses
(e.g., greens, fairways), for general purpose turf grasses, wine
grapes, table grapes, raisin grapes, fruit and nut trees, ground
fruits (e.g., strawberries, blueberries, blackberries), row crops
(e.g., tomatoes, celery, lettuce, leafy greens), root crops (e.g.,
tubers, potatoes, beets, carrots), mushrooms, and combinations and
variations of these.
[0325] Treated biochars and agriculture practices and methods,
provide for improved soil structure, increased water retention
capability, increased water holding ability of the soil over time,
reduced runoff or leaching, increased holding ability for
nutrients, increase holding of nutrients over time, and
combinations and variations of these, and other features that
relate to the increased holding and retention features and soil
aggregation of the present biochars and processes. It further being
understood that in addition to nutrients, other material additives,
(e.g., herbicide, pesticide), can be utilized and benefit from the
increased holding and retention capacities of the present biochars,
systems, and methods.
[0326] Treated biochar may also be used in other applications, for
example, such mixing with manure in holding ponds to potentially
reduce gaseous nitrogen losses, soil remedial (for example
absorption and capture of pesticide, contaminates, heavy metals, or
other undesirable, disadvantageous soil components), ground water
remediation, other bioremediations, storm water runoff remediation,
mine remediation, mercury remediation and as a cattle or poultry
feed additive.
[0327] Further, the present invention could be used to clean and/or
infiltrate the pores of biochar with a variety of substances, for a
number of purposes, including but not limited to, infiltrating the
pores of biochar with nutrients, vitamins, microbes, drugs and/or
other supplements, or a combination of any of the foregoing, for
consumption by either humans and/or animals. The treated biochar
may also be applied to animal pens, bedding, and/or other areas
where animal waste is present to reduce odor and emission of
unpleasant or undesirable vapors. Furthermore it may be applied to
compost piles to reduce odor, emissions, and temperature to enable
the use of the food waste and animal feed in composting. Biochar
can also be applied to areas where fertilizer or pesticide runoff
is occurring to slow or inhibit leaching and runoff. Additionally,
it can be used in the public health sector to help control disease,
for example carrying or deploying larvicides to reduce numbers of
certain disease carrying or transmitting insects. The biochar may
also be treated with additives which make it easier to dispense or
apply, such as non-toxic oils, anti-clumping/binding additives,
surface drying agents, or other materials.
[0328] In general, in the agricultural application of biochar to
soil, the biochar should be located near the soil's surface in the
root zone, or in or adjacent to the rhizosphere, where the bulk of
nutrient cycling and uptake by plants takes place. Although
benefits may be obtained from the application of biochar in layers
above, below, in and combinations and variation of these, the root
zone, for example during landscaping for carbon sequestration, or
if using biochar for moisture management. Layering of biochar at
various depths above, below, in and combinations and variation of
these, the root zone, the surface, and combinations and variations
of these, may also be employed. The biochar layers may have
different predetermined properties for each layer, based upon, for
example, the depth of the layer, soil type, geography, crop,
climate and other factors.
[0329] The above are only a few examples of how additive infused or
microbial carrying biochar may be produced for different uses.
Those skilled in the art will recognize that there may be other
mechanisms for infusing additives into the pores of the biochar
without departing from the scope of the invention. Those skilled in
the art will further recognize that the present invention can be
used on any type of soil application, including, but not limited
to, the following: crops, turf grasses, potted plants, flowering
plants, annuals, perennials, evergreens and seedlings. By way of
example, treated biochar may be incorporated into or around the
root zone of a plant. As most trees, rows, and specialty crops
extract large percentage of their water from the first twenty-four
inches below the soil surface, the above applications will
generally be effective incorporating the biochar around the root
zone from the top surface of the soil and up to a depth of 24''
below the top surface of the soil, depending on the plant type and
species, or alternatively, within a 24'' radius surrounding the
roots regardless of root depth or proximity from the top surface of
the soil. When the plant roots are closer to the surface, the
incorporation of the biochar within the top 2-6'' inches of the
soil surface may also be effective. Greater depths are more
beneficial for plants having larger root zones, such as trees.
[0330] In certain examples of biochar applications, the treated
biochar can be applied in amounts (e.g., rates of addition as
measured by weight of treated biochar per area of field) of from
about 0.001 ton of treated biochar per acre to about 150 tons of
treated biochar per acre, from about 2.5 tons of treated biochar
per acre to about 100 tons of treated biochar per acre, and from
about 5 tons of treated biochar per acre to about 70 tons of
treated biochar per acre, although larger and smaller amounts may
be used. Additional rates of from about 1/2 tons of treated biochar
to about 10 tons of treated biochar may be used. For example,
application rates of 1 ton of treated biochar was added per acre to
a soil for a lettuce crop where the soil had a pH of about 7. In
another example, about 3 tons per acre of treated biochar was added
to soil for a strawberry crop. In these examples, the plants showed
enhanced growth rates and yields.
[0331] Generally, for conventional field cropping systems, biochar
can be preferably added using existing farm equipment and
incorporated into existing farming operations. For example, treated
biochar can be applied and incorporated together with lime, since
lime is often applied as a fine solid, which must be well
incorporated into soil. However, it is also contemplated that the
examples of the present inventions may give rise to new equipment
and utilizations based upon the features, performance and
capabilities of the present inventions. Generally, treated biochar
may be applied to fields, by way of example through the use of
manure or compost spreaders, lime spreaders, plowing method (e.g.,
from hand hoes, animal draft plows, disc harrows, chisels, rotary
hoes, etc.), large scale tillage equipment, including rotary
tillers, mulch finishers, draw offset discs, and disc harrows (such
as for example JOHN DEERE DH51, DH52F, PC10, RT22, and RC22).
Treated biochar may also be applied by modified large scale
nutrient applicators (such as, for example, JOHN DEERE 2410C,
2510H, 25105 Strip-Till Medium Residue Applicator), large scale
draw dry spreaders (such as JOHN DEERE DN345), large scale no-till
planters, large scale dry fertilizer sub-surface applicators, and
liquid slurry surface or subsurface applicators. Similar, and
various other types of large farming, and earth moving and
manipulation equipment may be used to apply the treated biochar to
the field, such as for example, drop spreaders or drills.
[0332] For example, treated biochar may be applied using banding
techniques, which is an operation involving applying the biochar in
a narrow band, using equipment that cuts the soil open, without
disturbing the entire soil surface. Using this technique the
biochar can be placed inside the soil while minimizing soil
disturbance, making it possible to apply biochar after crop
establishment, among other applications.
[0333] In other examples, treated biochar may be mixed with other
soil amendments, or other materials, such as for example manure,
sand, topsoil, compost, turf grass substrate, peat, peat moss, or
lime before soil application, which are already scheduled or part
of the existing operations, and in this manner by combining these
steps (e.g., biochar application with existing application step)
can improve efficiency by reducing the number of field operations
required. In other examples, treated biochar can also be mixed with
liquid, (e.g., liquid manures) and applied as a slurry. Finer
biochar particles may be preferably used with this type of slurry
application using existing application equipment, and dust problems
associated with these finer particles may be mitigated, managed or
eliminated.
[0334] In further examples, treated biochar can be top dressed on
perennial pastures or other perennial vegetation, such as spaces
between fruit trees in orchards. Treated biochar may also be
applied with individual plants while transplanting or mixed with
topsoil and other amendments while preparing raised beds. In
forestry or similar operations where replanting of seedlings takes
place, treated biochar can be applied by broadcasting (e.g.,
surface application) or incorporation over the entire planting
area, it can be added in the planting holes, and combinations and
variations of these. Before or after tree establishment, biochar
could also be applied by traditional and subsurface banding or
top-dressed over perennial vegetation in orchards, but care should
be taken to minimize root damage and soil compaction.
[0335] In other examples of applications, treated biochar can be
applied in trenches radiating out from the base of established
trees ("radial trenching") or in holes dug at some distance from
the base of the tree ("vertical mulching"); biochar could also
potentially be applied to soil using "air excavation tools". These
tools use pressurized air to deliver material, e.g., compost, under
the soil surface and reduce compaction. Alternatively, the soil
around tree roots can be excavated and treated biochar applied
before covering with soil.
[0336] While, in some examples, particle size distribution of
treated biochar materials may vary widely depending on the
feedstock and the pyrolysis technique used to produce the biochar,
uniformity if required or preferred, can be achieved by various
milling and grinding techniques that may be employed during
processing or during the distribution and application to soil. When
smaller particles are utilized, and in particular for surface
applications, care should be taken to apply the treated biochar in
ways that minimize loss due to wind or water erosion.
[0337] As set forth above, the treated biochar of the present
invention may be used in various agriculture activities, and the
fields of edaphology and pedology, as well as other activities and
in other fields. Additionally, the treated biochar may be used, for
example, with: farming systems and technologies, operations or
activities that may be developed in the future; and with such
existing systems, operations or activities which may be modified,
in-part, based on the teachings of this specification. Further, the
various treated biochar and treatment processes set forth in this
specification may be used with each other in different and various
combinations. Thus, for example, the processes and resulting
biochar compositions provided in the various examples provided in
this specification may be used with each other; and the scope of
protection afforded the present inventions should not be limited to
any particular example, process, configuration, application or
arrangement that is set forth in a particular example or
figure.
[0338] Although this specification focuses on agriculture, soil
modification and plant growth, it should be understood that the
materials, compositions, structures, apparatus, methods, and
systems, taught and disclosed herein, may have applications and
uses for many other activities in addition to agriculture for
example, as filters, additives, and in remediation activities,
among other things.
[0339] It being understood that one or more of these may be
preferred for one application, and another of these may be
preferred for a different application. Thus, these are only a
general list of preferred features and are not required, necessary
and may not be preferred in all applications and uses.
[0340] It is noted that there is no requirement to provide or
address the theory underlying the novel and groundbreaking
functionality, performance or other beneficial features and
properties that are the subject of, or associated with, embodiments
of the present inventions. Nevertheless, to the extent that various
theories are provided in this specification to further advance the
art in this important area. These theories put forth in this
specification, and unless expressly stated otherwise, in no way
limit, restrict or narrow the scope of protection to be afforded
the claimed inventions. These theories many not be required or
practiced to utilize the present inventions. It is further
understood that the present inventions may lead to new, and
heretofore unknown theories to explain the functionality,
performance or other beneficial features and properties that are
the subject of, or associated with, embodiments of the methods,
articles, materials, and devices of the present inventions; and
such later developed theories shall not limit the scope of
protection afforded the present inventions.
[0341] Those skilled in the art will recognize that there are other
methods that may be used to treat biochar in a manner that forces
the infusion of liquids into the pores of the biochar without
departing from the scope of the invention. The foregoing
description of implementations has been presented for purposes of
illustration and description. It is not exhaustive and does not
limit the claimed inventions to the precise form disclosed.
Modifications and variations are possible in light of the above
description or may be acquired from practicing the invention. The
claims and their equivalents define the scope of the invention.
* * * * *
References