U.S. patent application number 14/299007 was filed with the patent office on 2014-09-25 for processing materials.
The applicant listed for this patent is Xyleco, Inc.. Invention is credited to Thomas Craig MASTERMAN, Marshall MEDOFF, Robert PARADIS.
Application Number | 20140286714 14/299007 |
Document ID | / |
Family ID | 51491991 |
Filed Date | 2014-09-25 |
United States Patent
Application |
20140286714 |
Kind Code |
A1 |
MEDOFF; Marshall ; et
al. |
September 25, 2014 |
PROCESSING MATERIALS
Abstract
Materials, such as biomass feedstocks (e.g., plant biomass,
animal biomass, and municipal waste biomass) are processed to
produce useful products, such as fuels. Conveying systems, such as
flowing gas conveying systems and such as closed-loop flowing gas
conveying systems are described.
Inventors: |
MEDOFF; Marshall;
(Brookline, MA) ; MASTERMAN; Thomas Craig;
(Rockport, MA) ; PARADIS; Robert; (Burlington,
MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Xyleco, Inc. |
Woburn |
MA |
US |
|
|
Family ID: |
51491991 |
Appl. No.: |
14/299007 |
Filed: |
June 9, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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PCT/US14/21632 |
Mar 7, 2014 |
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14299007 |
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61774684 |
Mar 8, 2013 |
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61774773 |
Mar 8, 2013 |
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61774731 |
Mar 8, 2013 |
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61774735 |
Mar 8, 2013 |
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61774740 |
Mar 8, 2013 |
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61774744 |
Mar 8, 2013 |
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61774746 |
Mar 8, 2013 |
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61774750 |
Mar 8, 2013 |
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61774752 |
Mar 8, 2013 |
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61774754 |
Mar 8, 2013 |
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61774775 |
Mar 8, 2013 |
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61774780 |
Mar 8, 2013 |
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61774761 |
Mar 8, 2013 |
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61774723 |
Mar 8, 2013 |
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61793336 |
Mar 15, 2013 |
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Current U.S.
Class: |
406/106 |
Current CPC
Class: |
C10L 1/026 20130101;
B01J 2219/0886 20130101; C10G 1/00 20130101; H01J 2237/31 20130101;
Y02E 50/30 20130101; B01D 61/445 20130101; B01J 2219/0869 20130101;
Y02E 60/16 20130101; B01J 19/085 20130101; G21K 5/10 20130101; B65G
53/40 20130101; C13K 13/002 20130101; C07C 29/149 20130101; D21C
9/007 20130101; G21F 7/00 20130101; C12P 7/04 20130101; B65G 53/04
20130101; B01D 53/32 20130101; C10L 2290/36 20130101; C12P 19/02
20130101; C12P 2201/00 20130101; Y02E 50/10 20130101; C12P 7/56
20130101; Y02W 10/37 20150501; B65G 27/00 20130101; C10L 1/023
20130101; C12P 2203/00 20130101; H01J 37/317 20130101; H01J
2237/3165 20130101; E04B 1/92 20130101; E04B 2001/925 20130101;
H01J 2237/202 20130101; C10L 9/08 20130101; B01D 61/44 20130101;
Y02W 10/33 20150501; C13K 1/02 20130101; C12M 47/00 20130101; C12P
7/10 20130101; C07C 31/12 20130101; Y02P 20/133 20151101; Y02W
10/40 20150501; B01J 2219/0879 20130101; C10L 2200/0476 20130101;
C12M 47/10 20130101; C12P 19/14 20130101; B01D 15/02 20130101; C12P
7/06 20130101; C12P 7/52 20130101; C10L 2200/0469 20130101; C07C
29/149 20130101; C07C 31/12 20130101 |
Class at
Publication: |
406/106 |
International
Class: |
B65G 53/40 20060101
B65G053/40 |
Claims
1. A method of conveying a material, the method comprising;
providing a recirculating gas flow at least a portion of which
passing through a radiation field having an intensity above
background levels, delivering a material through an ingress into
the recirculating gas flow, removing the material at an egress from
the recirculating gas flow.
2. The method of claim 1, wherein the material is conveyed by the
recirculating gas flow in the recirculating loop between the
ingress and egress.
3. The method of claim 1, wherein the ingress is positioned in the
radiation field having an intensity above background levels, and
the egress is positioned in an area having a radiation field
substantially the same as background levels.
4. The method of claim 1, wherein the recirculating gas flow is
enclosed.
5. The method of claim 1, further comprising delivering process
gases along with the material through the ingress to the
recirculating gas flow.
6. The method of claim 5, wherein the process gases are selected
from the group consisting of volatile organic compounds, hazardous
air pollutants, ozone and mixtures thereof.
7. The method of claim 1, further comprising sending at least a
portion of gas from the recirculating gas flow through an air
pollution control system.
8. The method of claim 7, wherein the air pollution control system
is in line with the recirculating gas flow.
9. The method of claim 7, wherein the pollution control system
includes an ozone abatement system.
10. The method of claim 7, wherein the air pollution control system
includes a metal oxide catalyst.
11. The method of claim 7, wherein the air pollution control system
includes activated carbon.
12. The method of claim 1, wherein a gas in the recirculating gas
is an inert gas.
13. The method of any one of the previous claims, wherein the gas
is nitrogen.
14. The method of claim 1, further comprising treating the material
with ionizing radiation.
15. The method of claim 14, wherein the ionizing radiation includes
an electron beam.
16. The method of claim 1, further comprising diverting a portion
of a gas in the recirculating gas flow out of the recirculating
flow.
17. The method of claim 16, wherein the portion of gas that is
diverted is diverted downstream from the ingress.
18. The method of claim 17, further comprising removing dust from
the recirculating gas upstream from where the gas is diverted.
20. The method of claim 1, wherein the material is a biomass
material.
21. The method of claim 20, wherein the biomass is a
lignocellulosic material.
22. The method of claim 1, wherein the material has a density of
less than 0.75 g/cm.sup.3.
23. The method of claim 1, wherein the material has been comminuted
and has a mean particle size between about 0.5 mm and 10 mm.
24. The method of claim 23, wherein material has been comminuted
and has an aspect ratio of greater than 2.
25. The method of claim 1, wherein the radiation field is created
by Bremsstrahlung X-rays.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of PCT/US14/21632 filed
Mar. 7, 2014 and claims priority to the following provisional
applications: U.S. Ser. No. 61/774,684, filed Mar. 8, 2013; U.S.
Ser. No. 61/774,773, filed Mar. 8, 2013; U.S. Ser. No. 61/774,731,
filed Mar. 8, 2013; U.S. Ser. No. 61/774,735, filed Mar. 8, 2013;
U.S. Ser. No. 61/774,740, filed Mar. 8, 2013; U.S. Ser. No.
61/774,744, filed Mar. 8, 2013; U.S. Ser. No. 61/774,746, filed
Mar. 8, 2013; U.S. Ser. No. 61/774,750, filed Mar. 8, 2013; U.S.
Ser. No. 61/774,752, filed Mar. 8, 2013; U.S. Ser. No. 61/774,754,
filed Mar. 8, 2013; U.S. Ser. No. 61/774,775, filed Mar. 8, 2013;
U.S. Ser. No. 61/774,780, filed Mar. 8, 2013; U.S. Ser. No.
61/774,761, filed Mar. 8, 2013; U.S. Ser. No. 61/774,723, filed
Mar. 8, 2013; and U.S. Ser. No. 61/793,336, filed Mar. 15, 2013.
The full disclosure of each of these applications is incorporated
by reference herein.
BACKGROUND
[0002] Many potential lignocellulosic feedstocks are available
today, including agricultural residues, woody biomass, municipal
waste, oilseeds/cakes and seaweed, to name a few. At present, these
materials are often under-utilized, being used, for example, as
animal feed, biocompost materials, burned in a co-generation
facility or even landfilled.
[0003] Lignocellulosic biomass includes crystalline cellulose
fibrils embedded in a hemicellulose matrix, surrounded by lignin.
This produces a compact matrix that is difficult to access by
enzymes and other chemical, biochemical and/or biological
processes. Cellulosic biomass materials (e.g., biomass material
from which the lignin has been removed) is more accessible to
enzymes and other conversion processes, but even so,
naturally-occurring cellulosic materials often have low yields
(relative to theoretical yields) when contacted with hydrolyzing
enzymes. Lignocellulosic biomass is even more recalcitrant to
enzyme attack. Furthermore, each type of lignocellulosic biomass
has its own specific composition of cellulose, hemicellulose and
lignin.
SUMMARY
[0004] Generally, the inventions relate to equipment, systems and
methods for processing materials, such as biomass. Many processes
are disclosed herein for saccharifying or liquefying a biomass
material, e.g., cellulosic, lignocellulosic and/or starchy
feedstocks, by converting biomass material to low molecular weight
sugars, e.g., saccharifying the feedstock using an enzyme, e.g.,
one or more cellulase and/or amylase. The invention also relates to
converting a feedstock to a product, e.g., by bioprocessing, such
as fermentation. The processes include novel methods of conveying
and cooling biomass feedstocks used in the above processes and
other related processes.
[0005] Inventions also feature equipment, systems and methods of
treating materials, e.g., biomass, with radiation, and methods and
equipment for conveying the material before, during, and after
treatment. In some cases the material is treated with multiple
passes of radiation and the methods and equipment disclosed herein
are used to convey the material between passes or treatment
units.
[0006] In one aspect, the invention features methods of reducing
the recalcitrance of a biomass material that include conveying
treated biomass materials out of a radiation zone utilizing a
recirculating gas flow.
[0007] In another aspect, the invention features methods of
reducing the recalcitrance of a biomass material that include
metering treated biomass materials, e.g., using an air lock, such
as a rotary valve, into a recirculating gas flow.
[0008] In one aspect, the invention relates to a method of
conveying a material, such as a biomass material (e.g., a
cellulosic, lignocellulosic or hydrocarbon containing material).
The method can include providing recirculating gas flow (e.g., a
recirculating gas flow in an enclosed loop), delivering a material
through an ingress into the recirculating gas flow and removing the
material at an egress from the recirculating gas flow. For example,
the material is conveyed by the recirculating gas flow in the
recirculating loop between the ingress and the egress. A portion of
the gas flow can pass through a radiation field having an intensity
above background levels. For example, the ingress can be positioned
in the radiation field having an intensity above background levels,
and the egress can be positioned in an area having a radiation
field substantially the same as background levels. For example, the
radiation field can be created by Bremsstrahlung X-rays. The method
can include delivering any process gas that may be present along
with the material to the recirculating gas flow. For example,
process gases that may have been produced while processing the
material, e.g., prior to it being conveyed by the recirculating gas
loop conveyor, can enter the gas flow with the material through the
ingress. Some examples of process gas can include gases selected
from the group consisting of volatile organic compounds (VOC),
hazardous air pollutants (HAP), ozone and mixtures of these.
[0009] In some implementations of the methods, at least a portion
of gas, e.g., at least 10%, at least 50% or substantially 100%,
from the recirculating gas flow passes through an air pollution
control system. For example, the pollution control system can be
in-line with the recirculating gas flow so that substantially all
of the gas in the recirculating gas flow flows through the
pollution control system (e.g., the pollution control system is in
series with the recirculating gas flow). Alternatively, or in
addition, a portion of the recirculating gas flow can be diverted
through a pollution control system (e.g., the diverted gas can be
in parallel with the gas flow so that it rejoins the gas flow, or
it can be removed from the gas flow to the atmosphere). In some
implementations, the pollution control system includes an ozone
abatement system. In some implementations, the pollution control
system includes a catalyst, for example a metal or metal oxide
catalyst. In some implementations, the pollution control system
includes activated carbon.
[0010] In some implementations of the method using the
recirculating gas flow, a gas (e.g., the entire gas in the gas flow
or a portion of this gas) includes at least 75% of an inert gas
(e.g., at least 80%, at least 85%, at least 90%, at least 95%, at
least 99%). In some implementations a gas in the recirculating flow
(e.g., the entire gas in the gas flow or a portion of this gas)
includes less than about 20% oxygen (e.g., less than about 15%,
less than about 10%, less than about 5%, less than about 1%). For
example, in some implementations, a gas in the recirculating gas
flow (e.g., the entire gas in the gas flow or a portion of this
gas) can include nitrogen, carbon dioxide and/or argon (e.g., more
than 80% N.sub.2, CO.sub.2 and/or Ar, more than 90% N.sub.2,
CO.sub.2 and/or Ar, more than 95% N.sub.2, CO.sub.2 and/or Ar, or
more than 99% N.sub.2, CO.sub.2 and/or Ar).
[0011] Alternatively, or in addition, the methods can include
irradiation of the material, e.g., prior to, before or during it
being conveyed by the recirculating flow. In some implementations,
the irradiation is with ionizing radiation, such as electron beam
irradiation.
[0012] In some implementations, the methods include diverting a
portion of a gas (e.g., producing a second gas flow) that is in the
recirculating gas flow, out of the recirculating loop. For example,
the portion that is diverted out of the gas flow can be diverted
downstream from the ingress for the material. Optionally, dust
(e.g., fine particles of the material), can be removed from the
recirculating gas flow upstream from where the gas is diverted. For
example, the dust can be removed from the gas flow that is diverted
from the recirculating gas flow. An example of a method for
removing dust particles includes using a dust bag.
[0013] The methods can be used, for example, to convey particulate
material. For example, the material can be a material that has been
comminuted, e.g., so that it can be conveyed by the air flow. In
some implementations, the materials have an average particle size
between about 0.5 mm and 10 mm. For example, having an average
particle size above at least about 0.5 mm (e.g., at least about
0.75 mm, at least about 1.00 mm) and below about 10 mm (e.g., below
about 6 mm, below about 3 mm, below about 2 mm). In some
implementations, the materials that are conveyed include materials
with a density of less than about 0.75 g/cm.sup.3 (e.g., less than
about 0.7, 0.65, 0.60, 0.50, 0.35, 0.25, 0.20, 0.15, 0.10, 0.05 or
even less than 0.025 g/cm.sup.3). In some other implementations,
the materials can also or alternatively include a material that
have been comminuted and has an aspect ratio of greater than 2.
[0014] In another aspect, the invention is a system for conveying a
material including a closed recirculating gas loop, a portion of
which being disposed in a radiation field having an intensity level
above background levels, and with an ingress into the loop for a
material and an egress out of the loop for the material. For
example, the system includes a material flow path disposed in the
loop and between the ingress and egress. The ingress can be in
fluid communication with delivery elements, the delivery elements
comprise a system (e.g., a device) for delivering the material to
the gas loop, for example a rotary valve that controls the flow of
the material from outside of the gas loop to the interior of the
gas loop. The delivery elements can be in fluid communication with
an input-conveyor, e.g., a conveyor that can convey a material such
as a belt conveyor, a screw conveyor, a hopper, a pneumatic
conveyor, a vibratory conveyor, a cooled conveyor or combinations
of these. For, example, a vibratory conveyor can deliver a
material, optionally to a hopper, and then to the delivery elements
which then deliver the material to the closed gas loop through the
ingress. Optionally, the egress is in fluid communication with an
output-conveyor. For example the output-conveyor can be selected
from the group consisting of a belt conveyor, a vibratory conveyor,
a pneumatic conveyor, a screw conveyor, a cooling conveyor, a
hopper or combinations of these
[0015] In some implementations, the system includes elements
designed for separating the material that is conveyed therein from
the gas in the recirculating gas loop. For example, the separating
elements can include one are more bag houses. Optionally, the
system can also include a pollution control system in fluid
communication with the recirculating gas loop. For example, the
pollution control system is in line with the recirculating gas
loop. Alternatively, or additionally, the recirculating gas loop
includes an outlet for diverting a portion of the gas flow
therefrom and through the pollution control system.
[0016] In some implementations, the system includes a gas (e.g., a
portion of the gas in the gas loop or substantially all of the gas
in the loop) in the recirculating gas loop that in composition is
less than about 20% oxygen. The system can also include a material
(e.g., a hydrocarbon containing material, a cellulosic material
and/or lignocellulosic material) in the recirculating gas loop
between the ingress and the egress (e.g., when the system is in
operation). For example, the system can be useful for conveying
biomass material and has biomass material between the ingress and
egress of the recirculating gas loop when the system is in
operation.
[0017] In some implementations, the material ingress for the system
is located (e.g., situated, disposed, placed, in fluid
communication with the) inside a vault and the material egress is
located (e.g., situated, disposed, placed, in fluid communication
with the) outside or on the exterior of the vault. Optionally, the
vault is constructed of radiation opaque materials.
[0018] In another aspect, the invention includes a biomass
conveying system, method or equipment. For example, the system can
include a closed recirculating gas loop with a portion of the loop
disposed inside a vault and a portion of the loop disposed outside
of the vault. The system also includes a biomass ingress to the
recirculating gas loop located inside the vault and a biomass
egress out of the loop located outside of the vault. Optionally,
the gas loop and vault form a substantially gas tight enclosure.
Also optionally, the gas loop and vault form a radiation tight
enclosure (e.g., X-ray, electron and photon tight). In some
implementations, the atmosphere in the vault includes a gas with
less than about 20% oxygen (e.g., less than about 15%, less than
about 10%, less than about 5%, less than about 1%). For example,
the atmosphere in the vault can be substantially nitrogen gas. The
gas in the enclosed recirculating gas loop and the vault can be
substantially the same. The vault can also include equipment for
treating biomass such as equipment to reduce the recalcitrance of
lignocellulosic material. For example, the vault can include one or
more electron beam irradiation devices. The portion of the
recirculating gas loop disposed inside the vault can be exposed to
a radiation field that is higher than background level (e.g.,
higher than the radiation level outside of the vault).
[0019] The methods and systems present an efficient and safe way to
process materials (e.g., biomass). For example biomass that is
treated to reduce its recalcitrance that can produce pollutants
such as volatile organic compounds, hazardous atmospheric
pollutants (HAP) and ozone. Ozone, for example, can be created by
electron beam irradiation in air. Conveying the material can
therefore release these pollutants to the environment. Some of the
methods described herein mitigate or even obviate these concerns by
removing the pollutants and/or reducing, or even eliminating, their
creation. For example, the methods, systems and equipment can allow
processing of materials in an inert environment, such as
nitrogen.
[0020] Implementations of the invention can optionally include one
or more of the following summarized features. In some
implementations, the selected features can be applied or utilized
in any order while in other implementations a specific selected
sequence is applied or utilized. Individual features can be applied
or utilized more than once in any sequence and even continuously.
In addition, an entire sequence, or a portion of a sequence, of
applied or utilized features can be applied or utilized once,
repeatedly or continuously in any order. In some optional
implementations, the features can be applied or utilized with
different, or where applicable the same, set or varied,
quantitative or qualitative parameters as determined by a person
skilled in the art. For example, parameters of the features such as
size, individual dimensions (e.g., length, width, height), location
of, degree (e.g., to what extent such as the degree of
recalcitrance), duration, frequency of use, density, concentration,
intensity and speed can be varied or set, where applicable as
determined by a person of skill in the art.
[0021] Features, for example, include: A method of conveying a
material; reducing the recalcitrance of a biomass material;
conveying treated biomass materials out of a radiation zone
utilizing a recirculating gas flow; metering treated biomass
materials using an air lock into a recirculating gas flow; metering
treated biomass materials using a rotary valve into a recirculating
gas flow; providing a recirculating gas flow at least a portion of
which passing through a radiation field having an intensity above
background levels; delivering a material through an ingress to a
recirculating gas flow; removing the material at an egress to a
recirculating gas flow; conveying material by a recirculating gas
flow of a recirculating gas loop between an ingress to the flow and
a egress to the flow; a recirculating gas flow that is enclosed;
delivering process gasses along with a material through the ingress
into a recirculating gas flow; delivering volatile organic
compounds through an ingress into a recirculating gas flow;
delivering hazardous air pollutants through an ingress into a
recirculating gas flow; delivering ozone through the ingress into a
recirculating gas flow; sending at least a portion of gas from a
recirculating gas flow through an air pollution control system;
sending at least a portion of gas from a recirculating gas flow
through an air pollution control system that is in line with a
recirculating gas flow; sending at least a portion of a gas from a
recirculating gas flow through an ozone abatement system; sending
at least a portion of a gas from a recirculating gas loop through a
metal oxide catalyst; sending at least a portion of a gas from a
recirculating gas loop through activated carbon; a gas that
includes at least 75% of an inert gas; a gas that includes at least
80% of an inert gas; a gas that includes at least 90% of an inert
gas; a gas that has less than about 20% oxygen; a gas that has less
than about 10% oxygen; a gas that includes nitrogen; treating a
material with ionizing radiation; treating a material with an
electron beam; diverting a portion of a gas in a recirculating gas
flow out of the recirculating flow; diverting a portion of a gas in
a recirculating gas flow out of the recirculating flow downstream
from a ingress for a material; removing dust from a recirculating
gas; removing dust from a recirculating gas or a portion of the
recirculating gas at any position e.g., upstream, downstream or in
parallel with any component in fluid communication with the
recirculating gas; a material that is a biomass material; a
material that is a lignocellulosic material; a material that has a
density of less than 0.75 g/cm.sup.3; the material has a density of
less than 0.7 g/cm.sup.3; a material that has a density of less
than 0.6 g/cm.sup.3; a material that has a density of less than 0.6
g/cm.sup.3; a material that has been comminuted and has a mean
particle size of at least 0.5 mm; a material that has been
comminuted and has a mean particle size of at least 0.75 mm; a
material that has been comminuted and has a mean particle size of
at least 1.00 mm; a material that has been comminuted and has a
mean particle size below about 10 mm; a material that has been
comminuted and has a mean particle size below about 6 mm; a
material that has been comminuted and has a mean particle size
below about 3 mm; a material that has been comminuted and has a
mean particle size below about 2 mm; a material that has been
comminuted and has an aspect ratio of greater than 2; a radiation
field that is created by Bremsstrahlung X-rays.
[0022] Some other features, for example, include: A system for
conveying a material; a closed recirculating gas loop with an
ingress for a material and an egress for the material, at least a
portion of which being disposed in a radiation field having an
intensity level above background level; a material flow path in a
closed recirculating gas loop, the flow path disposed between an
ingress for a material and an egress for the material; an ingress
is in fluid communication to delivery elements for delivering a
material to a recirculating gas loop; delivery elements for a
conveying system (e.g., a recirculating gas loop) that comprise a
rotary valve; a delivery element for a conveying system (e.g.,
including a recirculating gas loop) that in fluid communication
with an input-conveyor; an input-conveyor that is a vibratory
conveyor; an egress that includes elements for separating a
conveyed material from a gas in the recirculating gas loop;
elements for separating a material from a gas that includes a bag
house; an egress to a recirculating gas loop that is in fluid
communication with an output-conveyor; an egress to a recirculating
gas loop that is in fluid communication with a belt conveyor; an
egress to a recirculating gas loop that is in fluid communication
with a vibratory conveyor; an egress to a recirculating gas loop
that is in fluid communication with a pneumatic conveyor; an egress
to a recirculating gas loop that is in fluid communication with a
screw conveyor; an egress to a recirculating gas loop that is in
fluid communication with a cooling conveyor; a pollution control
system in fluid communication with the recirculating gas loop; a
pollution control system in fluid communication with the
recirculating gas loop in line with the recirculating gas loop; a
recirculating gas loop that includes an outlet for diverting a
portion of a gas in the gas loop t and through a pollution control
system; a gas in a recirculating gas loop that comprises less than
about 20% oxygen; a material ingress into a recirculating gas loop
that is situated in a vault and a material egress to the loop that
is situated on the exterior of the vault; a vault that is
constructed of radiation opaque materials; a vault that is
constructed with low porosity materials; utilizing a vault
constructed of low porosity concrete; utilizing a vault with walls
constructed of low porosity bricks; a biomass in a recirculating
gas loop between the ingress and the egress to the loop.
[0023] Other features, for example, include: A biomass conveying
system; a closed recirculating gas loop with a portion of the loop
disposed inside a vault; a closed recirculating gas loop with a
portion of the loop disposed outside of a vault; a biomass ingress
into a recirculating gas loop located inside a vault and an egress
for the biomass located outside of the vault; a gas loop and vault
that form a substantially gas tight enclosure; a gas loop and vault
that form a radiation tight enclosure; an atmosphere within a vault
comprising a gas with less than about 20% oxygen; a gas in a
recirculating gas loop comprising a gas with less than about 20%
oxygen; a portion of a recirculating gas loop disposed inside a
vault that is exposed to a radiation field that is higher than
background level.
[0024] Other features and advantages of the invention will be
apparent from the following detailed description, and from the
claims.
DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1A is a perspective view of a vault showing the flow of
biomass.
[0026] FIG. 1B is a detailed right side view of components of a
recirculating loop inside a vault.
[0027] FIG. 1C is a detailed perspective cutout view of the rotary
valve and feeding bin shown in FIG. 1B.
[0028] FIG. 2 is a detailed left side view of components of the
recirculating air loop.
[0029] FIG. 3A is a perspective view of a vault including a
recirculating air loop.
[0030] FIG. 3B is a side view of the vault and storage units
including a recirculating air loop.
DETAILED DESCRIPTION
[0031] Using the methods described herein; materials, e.g., biomass
(e.g., plant biomass, animal biomass, paper, and municipal waste
biomass) can be processed to produce useful intermediates and
products such as organic acids, salts of organic acids, anhydrides,
esters of organic acids and fuels, e.g., fuels for internal
combustion engines or feedstocks for fuel cells. Many methods
disclosed herein involve saccharification of biomass to produce
sugars, and in some cases fermentation of the resulting sugars to
form other products and/or intermediates. These steps, and other
steps involved in converting biomass to useful products and
intermediates, often include pretreatment of the biomass, e.g.,
with radiation or other treatments that raise the temperature of
the biomass and thus require multi-stage treatment to avoid
overheating the biomass. The systems described herein allow the
biomass to be conveyed to and from pretreatment, and back and forth
between multiple treatment steps, without releasing hazardous
process gases or particulate, e.g., ozone, volatile organic
compounds, and carbon containing fine particulates to the
atmosphere or deleteriously affecting the biomass.
[0032] These conveying systems, e.g., vacuum or pneumatic conveying
systems will be described in the context of a vaulted system, e.g.,
as would be used with certain radiation pretreatment equipment,
e.g., electron beam irradiating devices. By being closed loop in
design, these systems prevent gases, e.g., ozone rich air and
volatile organic compounds (VOCs), which can be harmful to breathe,
from leaking out of the work cell where irradiation takes place.
The closed loop also prevents or controls the release of
carbon-containing particles, e.g., biomass fines or soot, that can
also be hazardous, e.g., explosive or respiratory hazards.
Moreover, in terms of work and energy, these systems provide a
highly efficient way of transporting material in and out of the
work cell. Finally, in preferred implementations the systems have
no `daylight` openings that would allow radiation to escape.
[0033] Examples of conveying systems, e.g., vacuum and pneumatic
conveying systems, are shown in the figures.
[0034] FIG. 1A is a perspective view of a vault containing a
conveying system and a pretreatment work cell. Some of the vault
walls and the vault ceiling has been omitted to show the interior
equipment layout. Generally, the shown vault is photo-tight to
protect workers and/or the environment exterior to the vault from
Bremsstrahlung X-rays and intense light produced by electrons
striking material, e.g., metals, in the vault. In some instances,
the vault is configured to be air-tight so as to prevent the escape
of toxic process gasses e.g., VOCs, Ozone, NOx. In other instances,
the interior of the vault is maintained at a lower pressure than
region exterior of the vault to prevent toxic process gases from
being released from the vault. Exhaust system 155 can exhaust
process gasses out of the vault and can, for example, be adjusted
to maintain a negative pressure in the vault relative to the
pressure outside of the vault. The general flow of biomass in the
vault is indicated with solid arrows. Biomass is fed to a first
enclosed conveyor 110 by a pipe 120, configured to prevent clogging
by biomass e.g., having a diameter of at least 6 inches, at least 7
inches, at least 8 inches, at least 10 inches, at least 12 inches.
The conveying surface of the conveyor 110 can have a bias cut
(e.g., indicated by a dotted line on conveyor 110 in FIG. 1A) at an
end distal to the pipe 120, such that that the conveying surface
ends with the bias cut. Therefore, the conveyor 110, with the bias
cut, is configured to dump (e.g., pore or distribute) biomass to a
second enclosed conveyor 130, generally configured perpendicular to
first conveyor 110. The second conveyor 130 conveys the biomass
under the scan horn 140 of an electron beam device where it can be
irradiated through an electron-transparent foil window with little
energy loss. The biomass is then sent to a hopper (not fully
visible in the figure) disposed under the second conveyor. The
hopper feeds the biomass to section 150 of a recirculating air loop
through a rotating valve (not visible in this figure but shown in
FIGS. 1B and 1C). The air in section 150 of the recirculating air
loop then conveys the material up and out of the vault in the
direction of air flow. Return air, shown by dotted lines, enters
the vault and is brought under the rotary valve by section 151 of
the recirculating air loop. Any ozone, VOCs and lofted particulates
enter the closed loop and can be removed from the air prior to it
being sent back to the vault as will be discussed with reference to
the following figures. In addition or alternatively, an inert gas
such as nitrogen, carbon dioxide, argon and mixtures of these in
any concentration or proportion can be used instead of air. Biomass
and gases (e.g., air in the loop) that is sent out of the vault
through 150 can be processed by utilizing external
equipment/systems of the loop 157 such as solid separators (e.g.,
bag filters), heat exchangers, pollution control systems and pumps.
The air/gases, substantially stripped of solids, can then be
returned to the loop e.g., section 151. Details of some of these
external systems will be described with reference to FIG. 2.
[0035] In order to control the atmosphere in the vault, e.g., to
ensure an air tight structure and/or to contain process gases
and/or ensure the pressure in the vault is maintained at lower
pressure than the atmosphere outside the vault, the vaults can be
constructed of low porosity materials. For example, the porosity of
the walls can be reduced by infusion of materials into the
construction blocks. For example, concrete with lower permeability
can generally be achieved by substituting between 25 to 65 percent
slag cement for Portland cement. Finely-divided solids (e.g., lime,
silicates and colloidal silica) added to the cement when the blocks
are made can reduce permeability to water and gases by increasing
the density or by filling up voids. Some crystalline admixtures
react with water and cement particles in the concrete to form
calcium silicate hydrates and/or pore-blocking precipitates in the
existing microcracks and capillaries. The resulting crystalline
deposits, which are analogous to calcium silicate hydrate
formation, become integrally bound with the hydrated pastes.
Porosity reducing additives can also include hydrophobic
water-repellent chemicals based on soaps and long-chain fatty acids
derivatives, vegetable oils (tallows, soya-based materials, and
greases), and petroleum (mineral oil, paraffin waxes, and bitumen
emulsions). These materials are more useful for providing a water
repellency layer on the material and would be more usefully applied
to the exterior portions of the vault to aid in decreasing interior
vault humidity, which can exacerbate corrosion in the vault. In
addition, to improve the life of the structures, the interior
surfaces (e.g., of concrete blocks) can be coated or covered with a
corrosion resistant material, such as stainless steel.
[0036] FIG. 1B is a detailed right side view showing a portion of
the recirculating air loop where the return air, the direction of
flow of which is shown by dotted arrows, is charged with biomass
material 100. Biomass is delivered into the recirculating air loop
through a funnel 160 into a feeding bin 170, and flows in the
direction indicated by the solid arrows. A rotary valve system 180
under the feeding bin 170 then feeds the biomass to the
recirculating air loop. Only as small amount of air from the vault
is metered into the flowing air path 151-152, so that system 180
acts like a toxic gas air lock. As discussed above, the air in
section 150 of the recirculating air loop then carries the biomass
out of the vault. When the loop is in operation, air flow is about
300 ft.sup.3/min (e.g., between about 50 to 1000 ft.sup.3/min,
between about 50 to 800 ft.sup.3/min, between about 50 to 500
ft.sup.3/min, between about 100 to 400 ft.sup.3/min, between about
300 to 500 ft.sup.3/min, between about 150 to 350 ft.sup.3/min,
between about 300 to 600 ft.sup.3/min).
[0037] The rotary valve system 180 is enclosed in an enclosure 190.
The enclosure can be made of or include radiation opaque materials
(e.g., lead or lead lining) and can be purged (e.g., the interior
of the enclosure) with an inert gas or high flow of air to ensure
the components are protected from radiation and ozone.
[0038] FIG. 1C is a detailed perspective cutout view of the rotary
valve 180 and feeding bin 170. A motor 182 is coupled to shaft 184
through a pulley (e.g., a belt or chain) 186 that couples the drive
shaft of the motor 182 with the wheel 188. Alternatively, shaft 184
can be coupled to the motor 182 by a direct drive or gear motor.
Through these couplings, when the motor is engaged the shaft and
attached paddles (e.g., paddle 189) rotate in the direction
indicated by the arrow. The valve delivers (e.g., meters) portions
of biomass 100 to the section 150 of the recirculating air loop,
which acts as an air conveyor for the biomass, while keeping air
from the recirculating air loop from entering the feeding bin. Such
a system also reduces any potential process gases (e.g., toxic
gases) from entering from the vault through the rotary valve into
the flow pathway 151-150.
[0039] FIG. 2 is a detailed left side view of the components of the
recirculating air loop 250 (discussed above and now shown in its
entirety in FIG. 2). Dotted lines generally show the boundaries of
the foundation, walls and ceiling. The area A is the interior of
the vault. Arrows show the general direction of flow, with dotted
arrows indicating the general direction of flow of air, and solid
lines show the general direction of flow of biomass. Feed bin 170
and rotary valve enclosure 190 are also inside the vault as
discussed above. Biomass flows from the rotary valve, to a dust bag
system 210 (e.g., a bag house) of the recirculating air loop 250.
The dust bag system includes an inlet 212 for the biomass, a dust
bag 214 for trapping small particulates (e.g., biomass fines, dust
and/or soot), an outlet 216 for recirculating the air, an outlet
218 for large biomass particles (e.g. sent to further processing or
collection), and a gas draw off 219. The gasses that are drawn off
gas draw off 219 can be treated, for example, with a pollution
control system to remove and/or destroy and ozone, hazardous air
pollutants (HAP) and volatile organic compounds (VOC) as will be
discussed below. Gas draw off 219 can include an axial fan disposed
in a chamber (e.g., a tube) in fluid communication with the dust
bag and air flows therein as well as flow control valves. At 153
and 154, areas where the system 250 passes through vault walls, the
external walls of the pipes are made thicker with, for example,
lead. The thickness and distance along the pipe for this additional
thickness is designed to ensure X-rays do not emanate out of the
structure near 153 and 154.
[0040] After passing through the dust bag system, the air is cooled
by utilizing air-to-air heat exchanger 220. The system also
includes an air pollution control system 230 in line with the
recirculating air in the recirculating air loop 250. The pollution
control system can be used, for example, to remove/destroy ozone,
HAP and VOC. Vacuum pump system 240 keeps the air circulating in
the indicated direction in the recirculating air loop.
[0041] Air pressure adjusting systems can be disposed anywhere
along the gas flow path. For example, an inlet (e.g., one or more)
for allowing a gas into the system can be disposed anywhere along
the air flow path and can be configured and/or adjusted to
replenish the gas that is lost during operation of the
recirculating gas loop. In particular, gas that is lost at gas draw
off 219 can be replenished, for example by an inlet that is
operationally combined with vacuum pump system 240. For example, a
small inlet to allow a gas (e.g., air, nitrogen) to slightly
overpressure the system could be utilized (e.g., overpressure by
about 0.1%, 1%, 10%, 50%, 100%). Gases that are lost in the vault
can be vented through a vent system, for example the exhaust system
155. The vent system can include pumps/blowers to draw gas from
inside the vault to the exterior of the vault. The exhausted gases
can be treated e.g., with process gas mitigation/treatment systems
(e.g., ozone, VOCs systems). The Exhaust system can act constantly
or periodically to ensure that a negative pressure is maintained in
the vault.
[0042] FIG. 3A illustrates surrounding systems that can be used
with the closed air recirculating loop discussed above. FIG. 3A
shows a perspective view of a vault, including; part of the
recirculating air loop outside of the vault, a biomass feed storage
unit 310 and a treated biomass storage unit 320. Biomass from the
feed storage unit is conveyed by an auger screw system 312 to the
inlet to the vault. A screw conveyor 330 conveys biomass from the
dust bag system previously described to a second conveyor 340,
which then conveys material to the treated biomass storage unit
320. An auger screw system 322 can convey material from the treated
biomass storage back to the vault for additional treatment. In
other optional embodiments, the treated biomass can conveyed to a
second vault for a second treatment (e.g., a 3.sup.rd, 4.sup.th or
5.sup.th vault). If the biomass is treated a second time, the
second conveyor 340 can be redirected to a third storage unit (not
shown here). FIG. 3B shows a side view of the vault and storage
units including parts of the recirculating air loop 250 and other
components previously discussed.
[0043] Air pollution control technologies can be used for the
destruction of process gases, for example after removing gases from
the dust bag system at 219 and in the pollution control system 230.
Thermal oxidation can be utilized for the destruction of, for
example HAPs and VOCs. Since generally HAPs and VOCs are carbon
based, thermal oxidizer systems can be used to destroy these gases
by complete oxidation to carbon dioxide and water. Some types of
thermal oxidizer systems, for example, that can be utilized to
treat the process gases as described herein, are regenerative
thermal oxidizers, regenerative catalytic oxidizers, thermal
recuperative oxidizers and direct fired thermal oxidizer. The first
three thermal oxidizer systems can be preferable when designing for
high energy efficiency because they all include some form of energy
(e.g., heat) recovery and can have very high thermal efficiencies
(e.g., greater than 95%). Air pollution control technologies for
ozone generally include systems that convert ozone to oxygen. Other
process gases, for example, NO.sub.x can also be treated with
ammonia to produce nitrogen and water
[0044] Air pollution technologies often utilize a metal or metal
oxide catalyst. For example metal and metal oxide catalysts (e.g.,
CuO--MnO.sub.2, vanadium oxides, tungsten oxides, Pd and Pt). The
catalysts allow the conversion reactions (e.g., to CO.sub.2, to
O.sub.2, to N.sub.2 and/or water) to occur at relatively lower
temperatures, for example at temperatures as low as about 200 deg
C. (e.g., 100 to 400 deg C.) lower than without the catalysts). Air
pollution technologies also often utilized activated carbon. Ozone
can be reduced to oxygen directly utilizing an activated carbon
filter (e.g., bed, column). Activated carbons also act as an
adsorbent for VOCs and HAPs, selectively removing and holding the
gases on the surface until the carbon is regenerated. Activated
carbons can be utilized in any useful form, for example,
granulated, extruded, pelletized, powdered, acid washed, high
purity, polymer supported, as an aerogel and impregnated carbon
(e.g., with iodine, silver and metal ions, for example, Al, Mn, Zn,
Fe, Li, Ca metal ions).
[0045] The catalysts and activated carbon as described herein can
be utilized in an any useful configuration, e.g., pelletized,
extruded, supported (e.g., on silica, on alumina, on carbon, on
graphite, on aluminosilicates, on clays, on a foam, on a sponge, on
a mesh, on beads, on a honeycomb structure, on a ceramic, on a
woven or non-woven cloth, on a pleated filter, on a spiral filter,
on a layered filter), as a mesh, as a wire, as fibers, in a column
and/or on an filtering bed.
[0046] Optionally, process gases (e.g., components to be removed
and/or destroyed in the gas) can be concentrated using, for
example, a rotor concentrator and/or a centrifuge and then this
concentrated gas stream can be treated with the pollution control
systems described herein. Concentration can provide the advantage
of not requiring a high throughput of gas through one of the air
pollution control systems as described herein, so that a smaller
capacity (e.g., lower gas flow) system can be utilized. Optionally
the process gas stream can be split into two or more flows and each
flow treated independently.
[0047] The air pollution technologies and systems can be utilized
in combinations and in any order to treat the process gases. For
example, systems for destruction and/or removal of VOCs and HAPs
can be utilized prior to ozone destruction systems. Additional
systems can be utilized, for example, particulate filters, in
combinations with these systems. Removal of particulates, then
removal of VOCs and HAPs followed by Ozone removal can be preferred
to reduce catalyst deactivation (e.g., fouling and catalyst
poisoning can be reduced).
[0048] Some suppliers of process gas mitigation equipment (e.g.,
air pollution control technologies) and related supplies (e.g.,
filters, catalysts, activated carbon) include: Anguil Environmental
Systems, Inc. (Milwaukee, Wis.); PureSphere Co., Inc. (Korea);
General Air Products, Inc. (Exton, Pa.); Cabot Corp. (Boston,
Mass.); Corporate Consulting Service Instruments, Inc. (Arkon,
Ohio); Ozone Solutions, Inc. (Hull, Iowa); Columbus Industries,
Inc. (Ashville, Ohio); California Carbon Co., Inc (Wilmington,
Calif.); Calgon Carbon Corporation (Pittsburgh, Pa.); and General
Carbon Co. (Paterson, N.J.). Some specific ozone destructor units
that can be utilized in the methods described herein are; the
NT-400 unit available from Auguil Environmental Systems Inc. and/or
scaled up versions of this unit. An exemplary ozone destructor
system that can be utilized is the NT-400 or a scaled up version of
this system (e.g., so that high gas flow rates can be utilized),
available from Ozone Solutions, Inc.
[0049] Air pollution control technologies can be centralized. For
example the systems utilized to treat gases from 219 can be
consolidated at least in part with system 230. This consolidation
can serve to replace any air lost from gases removed at 219. For
example, they can be combined with other process gas controlling
systems such as ozone mitigation systems.
[0050] In addition or alternatively to using air in the
recirculating air system other gases can be used. For example,
inert cases selected from nitrogen, argon, helium, carbon dioxide
and mixtures of these. When combined with irradiating systems where
the irradiation can occur under an inert gas, the enclosed
circulating loop conveyor has the advantage of conserving the inert
gas. Some small makeup gas can be added to adjust for small leaks
in the system as previously discussed. For example, the makeup gas
(e.g., inert gas) can be added at any point of the recirculating
loop through an inlet. The advantage of utilizing the inert gas
would be reduction of ozone production. In the case of utilizing an
inert gas, for example nitrogen, the ozone filters can be by-passed
or removed from the closed loop. Other systems, such as the dust
bag system (e.g., baghouse), can be modified, for example, so that
valve system 219 draws out very little or no gas. In optional
embodiments, there is no valve system 219 to draw off gas or it is
completely shut off.
[0051] Some more details and reiterations of processes for treating
a feedstock that can be utilized, for example, with the embodiments
already discussed above, or in other embodiments, are described in
the following disclosures. The conveying systems discussed herein
can be utilized, for example, in processes that include the
feedstock treatment and processing steps described in the following
sections.
Systems for Treating a Feedstock
[0052] Processes for conversion of a feedstock to sugars and other
products, in which the conveying methods discuss above may be used,
can include, for example, optionally physically pre-treating the
feedstock, e.g., to reduce its size, before and/or after this
treatment, optionally treating the feedstock to reduce its
recalcitrance (e.g., by irradiation), and saccharifying the
feedstock to form a sugar solution. Saccharification can be
performed by mixing a dispersion of the feedstock in a liquid
medium, e.g., water with an enzyme, as will be discussed in detail
herein. Prior to treatment with an enzyme, pretreated biomass can
be subjected to hot water and pressure (e.g., 100-150 deg C.,
100-140 deg C. or 110-130 deg C. and associated pressure), and/or
an acid (e.g., about 0.01 to 1% H.sub.3PO.sub.4, about 0.05 to 0.5%
H.sub.3PO.sub.4 e.g. about 0.1% H.sub.3PO.sub.4). During or after
saccharification, the mixture (if saccharification is to be
partially or completely performed en route) or solution can be
transported, e.g., by pipeline, railcar, truck or barge, to a
manufacturing plant. At the plant, the solution can be
bioprocessed, e.g., fermented, to produce a desired product or
intermediate, which can then be processed further, e.g., by
distillation. The individual processing steps, materials used and
examples of products and intermediates that may be formed will be
described in detail below
Radiation Treatment
[0053] The feedstock can be treated with radiation to modify its
structure to reduce its recalcitrance. Such treatment can, for
example, reduce the average molecular weight of the feedstock,
change the crystalline structure of the feedstock, and/or increase
the surface area and/or porosity of the feedstock. Radiation can be
by, for example electron beam, ion beam, 100 nm to 280 nm
ultraviolet (UV) light, gamma or X-ray radiation. Radiation
treatments and systems for treatments are discussed in U.S. Pat.
No. 8,142,620, and U.S. patent application Ser. No. 12/417,731, the
entire disclosures of which are incorporated herein by
reference.
[0054] Each form of radiation ionizes biomass via particular
interactions, as determined by the energy of the radiation. Heavy
charged particles primarily ionize matter via Coulomb scattering;
furthermore, these interactions produce energetic electrons that
may further ionize matter. Alpha particles are identical to the
nucleus of a helium atom and are produced by the alpha decay of
various radioactive nuclei, such as isotopes of bismuth, polonium,
astatine, radon, francium, radium, several actinides, such as
actinium, thorium, uranium, neptunium, curium, californium,
americium, and plutonium. Electrons interact via Coulomb scattering
and Bremsstrahlung radiation produced by changes in the velocity of
electrons.
[0055] When particles are utilized, they can be neutral
(uncharged), positively charged or negatively charged. When
charged, the charged particles can bear a single positive or
negative charge, or multiple charges, e.g., one, two, three or even
four or more charges. In instances in which chain scission is
desired to change the molecular structure of the carbohydrate
containing material, positively charged particles may be desirable,
in part, due to their acidic nature. When particles are utilized,
the particles can have the mass of a resting electron, or greater,
e.g., 500, 1000, 1500, or 2000 or more times the mass of a resting
electron. For example, the particles can have a mass of from about
1 atomic unit to about 150 atomic units, e.g., from about 1 atomic
unit to about 50 atomic units, or from about 1 to about 25, e.g.,
1, 2, 3, 4, 5, 10, 12 or 15 atomic units.
[0056] Gamma radiation has the advantage of a significant
penetration depth into a variety of material in the sample.
[0057] In embodiments in which the irradiating is performed with
electromagnetic radiation, the electromagnetic radiation can have,
e.g., energy per photon (in electron volts) of greater than
10.sup.2 eV, e.g., greater than 10.sup.3, 10.sup.4, 10.sup.5,
10.sup.6, or even greater than 10.sup.7 eV. In some embodiments,
the electromagnetic radiation has energy per photon of between
10.sup.4 and 10.sup.7, e.g., between 10.sup.5 and 10.sup.6 eV. The
electromagnetic radiation can have a frequency of, e.g., greater
than 10.sup.16 Hz, greater than 10.sup.17 Hz, 10.sup.18, 10.sup.19,
10.sup.20, or even greater than 10.sup.21 Hz. In some embodiments,
the electromagnetic radiation has a frequency of between 10.sup.18
and 10.sup.22 Hz, e.g., between 10.sup.19 to 10.sup.21 Hz.
[0058] Electron bombardment may be performed using an electron beam
device that has a nominal energy of less than 10 MeV, e.g., less
than 7 MeV, less than 5 MeV, or less than 2 MeV, e.g., from about
0.5 to about 4 MeV, from about 0.6 to about 3 MeV, from about 0.5
to 1.5 MeV, from about 0.8 to 1.8 MeV, or from about 0.7 to 1 MeV.
In some implementations the nominal energy is about 500 to 800
keV.
[0059] The electron beam may have a relatively high total beam
power (the combined beam power of all accelerating heads, or, if
multiple accelerators are used, of all accelerators and all heads),
e.g., at least 25 kW, e.g., at least 30, 40, 50, 60, 65, 70, 80,
100, 125, or 150 kW. In some cases, the power is even as high as
500 kW, 750 kW, or even 1000 kW or more. In some cases the electron
beam has a beam power of 1200 kW or more, e.g., 1400, 1600, 1800,
or even 3000 kW.
[0060] This high total beam power is usually achieved by utilizing
multiple accelerating heads. For example, the electron beam device
may include two, four, or more accelerating heads. The use of
multiple heads, each of which has a relatively low beam power,
prevents excessive temperature rise in the material, thereby
preventing burning of the material, and also increases the
uniformity of the dose through the thickness of the layer of
material.
[0061] It is generally preferred that the bed of biomass material
has a relatively uniform thickness. In some embodiments the
thickness is less than about 1 inch (e.g., less than about 0.75
inches, less than about 0.5 inches, less than about 0.25 inches,
less than about 0.1 inches, between about 0.1 and 1 inch, between
about 0.2 and 0.3 inches).
[0062] It is desirable to treat the material as quickly as
possible. In general, it is preferred that treatment be performed
at a dose rate of greater than about 0.25 Mrad per second, e.g.,
greater than about 0.5, 0.75, 1, 1.5, 2, 5, 7, 10, 12, 15, or even
greater than about 20 Mrad per second, e.g., about 0.25 to 2 Mrad
per second. Higher dose rates allow a higher throughput for a
target (e.g., the desired) dose. Higher dose rates generally
require higher line speeds, to avoid thermal decomposition of the
material. In one implementation, the accelerator is set for 3 MeV,
50 mA beam current, and the line speed is 24 feet/minute, for a
sample thickness of about 20 mm (e.g., comminuted corn cob material
with a bulk density of 0.5 g/cm.sup.3).
[0063] In some embodiments, electron bombardment is performed until
the material receives a total dose of at least 0.1 Mrad, 0.25 Mrad,
1 Mrad, 5 Mrad, e.g., at least 10, 20, 30 or at least 40 Mrad. In
some embodiments, the treatment is performed until the material
receives a dose of from about 10 Mrad to about 50 Mrad, e.g., from
about 20 Mrad to about 40 Mrad, or from about 25 Mrad to about 30
Mrad. In some implementations, a total dose of 25 to 35 Mrad is
preferred, applied ideally over a couple of passes, e.g., at 5
Mrad/pass with each pass being applied for about one second.
Cooling methods, systems and equipment can be used before, during,
after and in between radiations, for example utilizing a cooling
screw conveyor and/or a cooled vibratory conveyor.
[0064] Using multiple heads as discussed above, the material can be
treated in multiple passes, for example, two passes at 10 to 20
Mrad/pass, e.g., 12 to 18 Mrad/pass, separated by a few seconds of
cool-down, or three passes of 7 to 12 Mrad/pass, e.g., 5 to 20
Mrad/pass, 10 to 40 Mrad/pass, 9 to 11 Mrad/pass. As discussed
herein, treating the material with several relatively low doses,
rather than one high dose, tends to prevent overheating of the
material and also increases dose uniformity through the thickness
of the material. In some implementations, the material is stirred
or otherwise mixed during or after each pass and then smoothed into
a uniform layer again before the next pass, to further enhance
treatment uniformity.
[0065] In some embodiments, electrons are accelerated to, for
example, a speed of greater than 75 percent of the speed of light,
e.g., greater than 85, 90, 95, or 99 percent of the speed of
light.
[0066] In some embodiments, any processing described herein occurs
on lignocellulosic material that remains dry as acquired or that
has been dried, e.g., using heat and/or reduced pressure. For
example, in some embodiments, the cellulosic and/or lignocellulosic
material has less than about 25 wt. % retained water, measured at
25.degree. C. and at fifty percent relative humidity (e.g., less
than about 20 wt. %, less than about 15 wt. %, less than about 14
wt. %, less than about 13 wt. %, less than about 12 wt. %, less
than about 10 wt. %, less than about 9 wt. %, less than about 8 wt.
%, less than about 7 wt. %, less than about 6 wt. %, less than
about 5 wt. %, less than about 4 wt. %, less than about 3 wt. %,
less than about 2 wt. %, less than about 1 wt. %, or less than
about 0.5 wt. %.
[0067] In some embodiments, two or more ionizing sources can be
used, such as two or more electron sources. For example, samples
can be treated, in any order, with a beam of electrons, followed by
gamma radiation and UV light having wavelengths from about 100 nm
to about 280 nm. In some embodiments, samples are treated with
three ionizing radiation sources, such as a beam of electrons,
gamma radiation, and energetic UV light. The biomass is conveyed
through the treatment zone where it can be bombarded with
electrons.
[0068] It may be advantageous to repeat the treatment to more
thoroughly reduce the recalcitrance of the biomass and/or further
modify the biomass. In particular the process parameters can be
adjusted after a first (e.g., second, third, fourth or more) pass
depending on the recalcitrance of the material. In some
embodiments, a conveyor can be used which includes a circular
system where the biomass is conveyed multiple times through the
various processes described above. In some other embodiments
multiple treatment devices (e.g., electron beam generators) are
used to treat the biomass multiple (e.g., 2, 3, 4 or more) times.
In yet other embodiments, a single electron beam generator may be
the source of multiple beams (e.g., 2, 3, 4 or more beams) that can
be used for treatment of the biomass.
[0069] The effectiveness in changing the molecular and/or
supermolecular structure and/or reducing the recalcitrance of the
carbohydrate-containing biomass depends on the electron energy used
and the dose applied, while exposure time depends on the power and
dose. In some embodiments, the dose rate and total dose are
adjusted so as not to destroy (e.g., char or burn) the biomass
material. For example, the carbohydrates should not be damaged in
the processing so that they can be released from the biomass
intact, e.g. as monomeric sugars.
[0070] In some embodiments, the treatment (with any electron source
or a combination of sources) is performed until the material
receives a dose of at least about 0.05 Mrad, e.g., at least about
0.1, 0.25, 0.5, 0.75, 1.0, 2.5, 5.0, 7.5, 10.0, 15, 20, 25, 30, 40,
50, 60, 70, 80, 90, 100, 125, 150, 175, or 200 Mrad. In some
embodiments, the treatment is performed until the material receives
a dose of between 0.1-100 Mrad, 1-200, 5-200, 10-200, 5-150, 50-150
Mrad, 5-100, 5-50, 5-40, 10-50, 10-75, 15-50, 20-35 Mrad.
[0071] In some embodiments, relatively low doses of radiation are
utilized, e.g., to increase the molecular weight of a cellulosic or
lignocellulosic material (with any radiation source or a
combination of sources described herein). For example, a dose of at
least about 0.05 Mrad, e.g., at least about 0.1 Mrad or at least
about 0.25, 0.5, 0.75. 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, or at
least about 5.0 Mrad. In some embodiments, the irradiation is
performed until the material receives a dose of between 0.1 Mrad
and 2.0 Mrad, e.g., between 0.5 rad and 4.0 Mrad or between 1.0
Mrad and 3.0 Mrad.
[0072] It also can be desirable to irradiate from multiple
directions, simultaneously or sequentially, in order to achieve a
desired degree of penetration of radiation into the material. For
example, depending on the density and moisture content of the
material, such as wood, and the type of radiation source used
(e.g., gamma or electron beam), the maximum penetration of
radiation into the material may be only about 0.75 inch. In such a
cases, a thicker section (up to 1.5 inch) can be irradiated by
first irradiating the material from one side, and then turning the
material over and irradiating from the other side. Irradiation from
multiple directions can be particularly useful with electron beam
radiation, which irradiates faster than gamma radiation but
typically does not achieve as great a penetration depth.
Radiation Opaque Materials
[0073] As previously discussed, the invention can include
processing the material in a vault and/or bunker that is
constructed using radiation opaque materials. In some
implementations, the radiation opaque materials are selected to be
capable of shielding the components from X-rays with high energy
(short wavelength), which can penetrate many materials. One
important factor in designing a radiation shielding enclosure is
the attenuation length of the materials used, which will determine
the required thickness for a particular material, blend of
materials, or layered structure. The attenuation length is the
penetration distance at which the radiation is reduced to
approximately 1/e (e=Eulers number) times that of the incident
radiation. Although virtually all materials are radiation opaque if
thick enough, materials containing a high compositional percentage
(e.g., density) of elements that have a high Z value (atomic
number) have a shorter radiation attenuation length and thus if
such materials are used a thinner, lighter shielding can be
provided. Examples of high Z value materials that are used in
radiation shielding are tantalum and lead. Another important
parameter in radiation shielding is the halving distance, which is
the thickness of a particular material that will reduce gamma ray
intensity by 50%. As an example for X-ray radiation with an energy
of 0.1 MeV the halving thickness is about 15.1 mm for concrete and
about 2.7 mm for lead, while with an X-ray energy of 1 MeV the
halving thickness for concrete is about 44.45 mm and for lead is
about 7.9 mm. Radiation opaque materials can be materials that are
thick or thin so long as they can reduce the radiation that passes
through to the other side. Thus, if it is desired that a particular
enclosure have a low wall thickness, e.g., for light weight or due
to size constraints, the material chosen should have a sufficient Z
value and/or attenuation length so that its halving length is less
than or equal to the desired wall thickness of the enclosure.
[0074] In some cases, the radiation opaque material may be a
layered material, for example having a layer of a higher Z value
material, to provide good shielding, and a layer of a lower Z value
material to provide other properties (e.g., structural integrity,
impact resistance, etc.). In some cases, the layered material may
be a "graded-Z" laminate, e.g., including a laminate in which the
layers provide a gradient from high-Z through successively lower-Z
elements. In some cases the radiation opaque materials can be
interlocking blocks, for example, lead and/or concrete blocks can
be supplied by NELCO Worldwide (Burlington, Mass.), and
reconfigurable vaults can be utilized.
[0075] A radiation opaque material can reduce the radiation passing
through a structure (e.g., a wall, door, ceiling, enclosure, a
series of these or combinations of these) formed of the material by
about at least about 10%, (e.g., at least about 20%, at least about
30%, at least about 40%, at least about 50%, at least about 60%, at
least about 70%, at least about 80%, at least about 90%, at least
about 95%, at least about 96%, at least about 97%, at least about
98%, at least about 99%, at least about 99.9%, at least about
99.99%, at least about 99.999%) as compared to the incident
radiation. Therefore, an enclosure made of a radiation opaque
material can reduce the exposure of equipment/system/components by
the same amount. Radiation opaque materials can include stainless
steel, metals with Z values above 25 (e.g., lead, iron), concrete,
dirt, sand and combinations thereof. Radiation opaque materials can
include a barrier in the direction of the incident radiation of at
least about 1 mm (e.g., 5 mm, 10 mm, 5 cm, 10 cm, 100 cm, 1 m, 10
m).
Radiation Sources
[0076] The type of radiation determines the kinds of radiation
sources used as well as the radiation devices and associated
equipment. The methods, systems and equipment described herein, for
example for treating materials with radiation, can utilized sources
as described herein as well as any other useful source.
[0077] Sources of gamma rays include radioactive nuclei, such as
isotopes of cobalt, calcium, technetium, chromium, gallium, indium,
iodine, iron, krypton, samarium, selenium, sodium, thallium, and
xenon.
[0078] Sources of X-rays include electron beam collision with metal
targets, such as tungsten or molybdenum or alloys, or compact light
sources, such as those produced commercially by Lyncean.
[0079] Alpha particles are identical to the nucleus of a helium
atom and are produced by the alpha decay of various radioactive
nuclei, such as isotopes of bismuth, polonium, astatine, radon,
francium, radium, several actinides, such as actinium, thorium,
uranium, neptunium, curium, californium, americium, and
plutonium.
[0080] Sources for ultraviolet radiation include deuterium or
cadmium lamps.
[0081] Sources for infrared radiation include sapphire, zinc, or
selenide window ceramic lamps.
[0082] Sources for microwaves include klystrons, Slevin type RF
sources, or atom beam sources that employ hydrogen, oxygen, or
nitrogen gases.
[0083] Accelerators used to accelerate the particles (e.g.,
electrons or ions) can be DC (e.g., electrostatic DC or
electrodynamic DC), RF linear, magnetic induction linear or
continuous wave. For example, various irradiating devices may be
used in the methods disclosed herein, including field ionization
sources, electrostatic ion separators, field ionization generators,
thermionic emission sources, microwave discharge ion sources,
recirculating or static accelerators, dynamic linear accelerators,
van de Graaff accelerators, Cockroft Walton accelerators (e.g.,
PELLETRON.RTM. accelerators), LINACS, Dynamitrons (e.g.,
DYNAMITRON.RTM. accelerators), cyclotrons, synchrotrons, betatrons,
transformer-type accelerators, microtrons, plasma generators,
cascade accelerators, and folded tandem accelerators. For example,
cyclotron type accelerators are available from IBA, Belgium, such
as the RHODOTRON.TM. system, while DC type accelerators are
available from RDI, now IBA Industrial, such as the
DYNAMITRON.RTM.. Other suitable accelerator systems include, for
example: DC insulated core transformer (ICT) type systems,
available from Nissin High Voltage, Japan; S-band LINACs, available
from L3-PSD (USA), Linac Systems (France), Mevex (Canada), and
Mitsubishi Heavy Industries (Japan); L-band LINACs, available from
Iotron Industries (Canada); and ILU-based accelerators, available
from Budker Laboratories (Russia). Ions and ion accelerators are
discussed in Introductory Nuclear Physics, Kenneth S. Krane, John
Wiley & Sons, Inc. (1988), Krsto Prelec, FIZIKA B 6 (1997) 4,
177-206, Chu, William T., "Overview of Light-Ion Beam Therapy",
Columbus-Ohio, ICRU-IAEA Meeting, 18-20 Mar. 2006, Iwata, Y. et
al., "Alternating-Phase-Focused IH-DTL for Heavy-Ion Medical
Accelerators", Proceedings of EPAC 2006, Edinburgh, Scotland, and
Leitner, C. M. et al., "Status of the Superconducting ECR Ion
Source Venus", Proceedings of EPAC 2000, Vienna, Austria. Some
particle accelerators and their uses are disclosed, for example, in
U.S. Pat. No. 7,931,784 to Medoff, the complete disclosure of which
is incorporated herein by reference.
[0084] Electrons may be produced by radioactive nuclei that undergo
beta decay, such as isotopes of iodine, cesium, technetium, and
iridium. Alternatively, an electron gun can be used as an electron
source via thermionic emission and accelerated through an
accelerating potential. An electron gun generates electrons, which
are then accelerated through a large potential (e.g., greater than
about 500 thousand, greater than about 1 million, greater than
about 2 million, greater than about 5 million, greater than about 6
million, greater than about 7 million, greater than about 8
million, greater than about 9 million, or even greater than 10
million volts) and then scanned magnetically in the x-y plane,
where the electrons are initially accelerated in the z direction
down the accelerator tube and extracted through a foil window.
Scanning the electron beams is useful for increasing the
irradiation surface when irradiating materials, e.g., a biomass,
that is conveyed through the scanned beam. Scanning the electron
beam also distributes the thermal load homogenously on the window
and helps reduce the foil window rupture due to local heating by
the electron beam. Window foil rupture is a cause of significant
down-time due to subsequent necessary repairs and re-starting the
electron gun.
[0085] Various other irradiating devices may be used in the methods
disclosed herein, including field ionization sources, electrostatic
ion separators, field ionization generators, thermionic emission
sources, microwave discharge ion sources, recirculating or static
accelerators, dynamic linear accelerators, van de Graaff
accelerators, and folded tandem accelerators. Such devices are
disclosed, for example, in U.S. Pat. No. 7,931,784 to Medoff, the
complete disclosure of which is incorporated herein by
reference.
[0086] A beam of electrons can be used as the radiation source. A
beam of electrons has the advantages of high dose rates (e.g., 1,
5, or even 10 Mrad per second), high throughput, less containment,
and less confinement equipment. Electron beams can also have high
electrical efficiency (e.g., 80%), allowing for lower energy usage
relative to other radiation methods, which can translate into a
lower cost of operation and lower greenhouse gas emissions
corresponding to the smaller amount of energy used. Electron beams
can be generated, e.g., by electrostatic generators, cascade
generators, transformer generators, low energy accelerators with a
scanning system, low energy accelerators with a linear cathode,
linear accelerators, and pulsed accelerators.
[0087] Electrons can also be more efficient at causing changes in
the molecular structure of carbohydrate-containing materials, for
example, by the mechanism of chain scission. In addition, electrons
having energies of 0.5-10 MeV can penetrate low density materials,
such as the biomass materials described herein, e.g., materials
having a bulk density of less than 0.5 g/cm.sup.3, and a depth of
0.3-10 cm. Electrons as an ionizing radiation source can be useful,
e.g., for relatively thin piles, layers or beds of materials, e.g.,
less than about 0.5 inch, e.g., less than about 0.4 inch, 0.3 inch,
0.25 inch, or less than about 0.1 inch. In some embodiments, the
energy of each electron of the electron beam is from about 0.3 MeV
to about 2.0 MeV (million electron volts), e.g., from about 0.5 MeV
to about 1.5 MeV, or from about 0.7 MeV to about 1.25 MeV. Methods
of irradiating materials are discussed in U.S. Pat. App. Pub.
2012/0100577 A1, filed Oct. 18, 2011, the entire disclosure of
which is herein incorporated by reference.
[0088] Electron beam irradiation devices may be procured
commercially or built. For example elements or components such
inductors, capacitors, casings, power sources, cables, wiring,
voltage control systems, current control elements, insulating
material, microcontrollers and cooling equipment can be purchased
and assembled into a device. Optionally, a commercial device can be
modified and/or adapted. For example, devices and components can be
purchased from any of the commercial sources described herein
including Ion Beam Applications (Louvain-la-Neuve, Belgium), Wasik
Associates inc. (Dracut, Mass.), NHV Corporation (Japan), the Titan
Corporation (San Diego, Calif.), Vivirad High Voltage Corp
(Billerica, Mass.) and/or Budker Laboratories (Russia). Typical
electron energies can be 0.5 MeV, 1 MeV, 2 MeV, 4.5 MeV, 7.5 MeV,
or 10 MeV. Typical electron beam irradiation device power can be 1
kW, 5 kW, 10 kW, 20 kW, 50 kW, 60 kW, 70 kW, 80 kW, 90 kW, 100 kW,
125 kW, 150 kW, 175 kW, 200 kW, 250 kW, 300 kW, 350 kW, 400 kW, 450
kW, 500 kW, 600 kW, 700 kW, 800 kW, 900 kW or even 1000 kW.
Accelerators that can be used include NHV irradiators medium energy
series EPS-500 (e.g., 500 kV accelerator voltage and 65, 100 or 150
mA beam current), EPS-800 (e.g., 800 kV accelerator voltage and 65
or 100 mA beam current), or EPS-1000 (e.g., 1000 kV accelerator
voltage and 65 or 100 mA beam current). Also, accelerators from
NHV's high energy series can be used such as EPS-1500 (e.g., 1500
kV accelerator voltage and 65 mA beam current), EPS-2000 (e.g.,
2000 kV accelerator voltage and 50 mA beam current), EPS-3000
(e.g., 3000 kV accelerator voltage and 50 mA beam current) and
EPS-5000 (e.g., 5000 and 30 mA beam current).
[0089] Tradeoffs in considering electron beam irradiation device
power specifications include cost to operate, capital costs,
depreciation, and device footprint. Tradeoffs in considering
exposure dose levels of electron beam irradiation would be energy
costs and environment, safety, and health (ESH) concerns.
Typically, generators are housed in a vault, e.g., of lead or
concrete, especially for production from X-rays that are generated
in the process. Tradeoffs in considering electron energies include
energy costs.
[0090] The electron beam irradiation device can produce either a
fixed beam or a scanning beam. A scanning beam may be advantageous
with large scan sweep length and high scan speeds, as this would
effectively replace a large, fixed beam width. Further, available
sweep widths of 0.5 m, 1 m, 2 m or more are available. The scanning
beam is preferred in most embodiments described herein because of
the larger scan width and reduced possibility of local heating and
failure of the windows.
Electron Guns
Windows
[0091] The extraction system for an electron accelerator can
include two window foils. The cooling gas in the two foil window
extraction system can be a purge gas or a mixture, for example air,
or a pure gas. In one embodiment the gas is an inert gas such as
nitrogen, argon, helium and or carbon dioxide. It is preferred to
use a gas rather than a liquid since energy losses to the electron
beam are minimized. Mixtures of pure gas can also be used, either
pre-mixed or mixed in line prior to impinging on the windows or in
the space between the windows. The cooling gas can be cooled, for
example, by using a heat exchange system (e.g., a chiller) and/or
by using boil off from a condensed gas (e.g., liquid nitrogen,
liquid helium). Window foils are described in PCT/US2013/64332
filed Oct. 10, 2013 the full disclosure of which is incorporated by
reference herein.
Heating and Throughput During Radiation Treatment
[0092] Several processes can occur in biomass when electrons from
an electron beam interact with matter in inelastic collisions. For
example, ionization of the material, chain scission of polymers in
the material, cross linking of polymers in the material, oxidation
of the material, generation of X-rays ("Bremsstrahlung") and
vibrational excitation of molecules (e.g. phonon generation).
Without being bound to a particular mechanism, the reduction in
recalcitrance can be due to several of these inelastic collision
effects, for example ionization, chain scission of polymers,
oxidation and phonon generation. Some of the effects (e.g.,
especially X-ray generation), necessitate shielding and engineering
barriers, for example, enclosing the irradiation processes in a
concrete (or other radiation opaque material) vault. Another effect
of irradiation, vibrational excitation, is equivalent to heating up
the sample. Heating the sample by irradiation can help in
recalcitrance reduction, but excessive heating can destroy the
material, as will be explained below.
[0093] The adiabatic temperature rise (.DELTA.T) from adsorption of
ionizing radiation is given by the equation: .DELTA.T=D/Cp: where D
is the average dose in kGy, C.sub.p is the heat capacity in J/g
.degree. C., and .DELTA.T is the change in temperature in .degree.
C. A typical dry biomass material will have a heat capacity close
to 2. Wet biomass will have a higher heat capacity dependent on the
amount of water since the heat capacity of water is very high (4.19
J/g .degree. C.). Metals have much lower heat capacities, for
example 304 stainless steel has a heat capacity of 0.5 J/g .degree.
C. The temperature change due to the instant adsorption of
radiation in a biomass and stainless steel for various doses of
radiation is shown in Table 1. At the higher temperatures biomass
will decompose causing extreme deviation from the estimated changes
in temperature.
TABLE-US-00001 TABLE 1 Calculated Temperature increase for biomass
and stainless steel. Dose (Mrad) Estimated Biomass .DELTA.T
(.degree. C.) Steel .DELTA.T (.degree. C.) 10 50 200 50 250
(decomposed) 1000 100 500 (decomposed) 2000 150 750 (decomposed)
3000 200 1000 (decomposed) 4000
[0094] High temperatures can destroy and or modify the biopolymers
in biomass so that the polymers (e.g., cellulose) are unsuitable
for further processing. A biomass subjected to high temperatures
can become dark, sticky and give off odors indicating
decomposition. The stickiness can even make the material hard to
convey. The odors can be unpleasant and be a safety issue. In fact,
keeping the biomass below about 200.degree. C. has been found to be
beneficial in the processes described herein (e.g., below about
190.degree. C., below about 180.degree. C., below about 170.degree.
C., below about 160.degree. C., below about 150.degree. C., below
about 140.degree. C., below about 130.degree. C., below about
120.degree. C., below about 110.degree. C., between about
60.degree. C. and 180.degree. C., between about 60.degree. C. and
160.degree. C., between about 60.degree. C. and 150.degree. C.,
between about 60.degree. C. and 140.degree. C., between about
60.degree. C. and 130.degree. C., between about 60.degree. C. and
120.degree. C., between about 80.degree. C. and 180.degree. C.,
between about 100.degree. C. and 180.degree. C., between about
120.degree. C. and 180.degree. C., between about 140.degree. C. and
180.degree. C., between about 160.degree. C. and 180.degree. C.,
between about 100.degree. C. and 140.degree. C., between about
80.degree. C. and 120.degree. C.).
[0095] It has been found that irradiation above about 10 Mrad is
desirable for the processes described herein (e.g., reduction of
recalcitrance). A high throughput is also desirable so that the
irradiation does not become a bottle neck in processing the
biomass. The treatment is governed by a Dose rate equation:
M=FP/Dtime, where M is the mass of irradiated material (Kg), F is
the fraction of power that is adsorbed (unit less), P is the
emitted power (kW=Voltage in MeV.times.Current in mA), time is the
treatment time (sec) and D is the adsorbed dose (kGy). In an
exemplary process where the fraction of adsorbed power is fixed,
the Power emitted is constant and a set dosage is desired, the
throughput (e.g., M, the biomass processed) can be increased by
increasing the irradiation time. However, increasing the
irradiation time without allowing the material to cool, can
excessively heat the material as exemplified by the calculations
shown above. Since biomass has a low thermal conductivity (less
than about 0.1 Wm.sup.-1K.sup.-1), heat dissipation is slow,
unlike, for example metals (greater than about 10
Wm.sup.-1K.sup.-1) which can dissipate energy quickly as long as
there is a heat sink to transfer the energy to.
Electron Guns
Beam Stops
[0096] In some embodiments the systems and methods include a beam
stop (e.g., a shutter). For example, the beam stop can be used to
quickly stop or reduce the irradiation of material without powering
down the electron beam device. Alternatively the beam stop can be
used while powering up the electron beam, e.g., the beam stop can
stop the electron beam until a beam current of a desired level is
achieved. The beam stop can be placed between the primary foil
window and a secondary foil window. For example the beam stop can
be mounted so that it is movable, that is, so that it can be moved
into and out of the beam path. Even partial coverage of the beam
can be used, for example, to control the dose of irradiation. The
beam stop can be mounted to the floor, to a conveyor for the
biomass, to a wall, to the radiation device (e.g., at the scan
horn), or to any structural support. Preferably the beam stop is
fixed in relation to the scan horn so that the beam can be
effectively controlled by the beam stop. The beam stop can
incorporate a hinge, a rail, wheels, slots, or other means allowing
for its operation in moving into and out of the beam. The beam stop
can be made of any material that will stop at least 5% of the
electrons, e.g., at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, at
least 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or
even about 100% of the electrons.
[0097] The beam stop can be made of a metal including, but not
limited to, stainless steel, lead, iron, molybdenum, silver, gold,
titanium, aluminum, tin, or alloys of these, or laminates (layered
materials) made with such metals (e.g., metal-coated ceramic,
metal-coated polymer, metal-coated composite, multilayered metal
materials). Optionally beam stops can be made of corrosion
resistant materials. The beam stops can include structural
materials that include stainless steel (e.g., 304, 316 stainless
steel, HASTELLOY.RTM. ALLOYS and INCONEL.RTM. Alloys). For example,
HASTELLOY.RTM. Corrosion-Resistant alloys from Hynes (Kokomo, Ind.,
USA) such as HASTELLOY.RTM. B-3.RTM. ALLOY, HASTELLOY.RTM.
HYBRID-BC1.RTM. ALLOY, HASTELLOY.RTM. C-4 ALLOY, HASTELLOY.RTM.
C-22.RTM. ALLOY, HASTELLOY.RTM. C-22HS.RTM. ALLOY, HASTELLOY.RTM.
C-276 ALLOY, HASTELLOY.RTM. C-2000.RTM. ALLOY, HASTELLOY.RTM.
G-30.RTM. ALLOY, HASTELLOY.RTM. G-35.RTM. ALLOY, HASTELLOY.RTM. N
ALLOY and HASTELLOY.RTM. ULTIMET.RTM. alloy.
[0098] The beam stop can be cooled, for example, with a cooling
fluid such as an aqueous solution or a gas. The beam stop can be
partially or completely hollow, for example with cavities. Interior
spaces of the beam stop can be used for cooling fluids and gases.
The beam stop can be of any shape, including flat, curved, round,
oval, square, rectangular, beveled and wedged shapes.
[0099] The beam stop can have perforations so as to allow some
electrons through, thus controlling (e.g., reducing) the levels of
radiation across the whole area of the window, or in specific
regions of the window. The beam stop can be a mesh formed, for
example, from fibers or wires. Multiple beam stops can be used,
together or independently, to control the irradiation. The beam
stop can be remotely controlled, e.g., by radio signal or hard
wired to a motor for moving the beam into or out of position.
Beam Dumps
[0100] The embodiments disclosed herein can also include a beam
dump. A beam dump's purpose is to safely absorb a beam of charged
particles. Like a beam stop, a beam dump can be used to block the
beam of charged particles. However, a beam dump is much more robust
than a beam stop, and is intended to block the full power of the
electron beam for an extended period of time. They are often used
to block the beam as the accelerator is powering up.
[0101] Beam dumps are also designed to accommodate the heat
generated by such beams, and are usually made from materials such
as copper, aluminum, carbon, beryllium, tungsten, or mercury. Beam
dumps can be cooled, for example by using a cooling fluid that is
in thermal contact with the beam dump.
Biomass Materials
[0102] Lignocellulosic materials include, but are not limited to,
wood, particle board, forestry wastes (e.g., sawdust, aspen wood,
wood chips), grasses, (e.g., switchgrass, miscanthus, cord grass,
reed canary grass), grain residues, (e.g., rice hulls, oat hulls,
wheat chaff, barley hulls), agricultural waste (e.g., silage,
canola straw, wheat straw, barley straw, oat straw, rice straw,
jute, hemp, flax, bamboo, sisal, abaca, corn cobs, corn stover,
soybean stover, corn fiber, alfalfa, hay, coconut hair), sugar
processing residues (e.g., bagasse, beet pulp, agave bagasse),
algae, seaweed, manure, sewage, and mixtures of any of these.
[0103] In some cases, the lignocellulosic material includes
corncobs. Ground or hammermilled corncobs can be spread in a layer
of relatively uniform thickness for irradiation, and after
irradiation are easy to disperse in the medium for further
processing. To facilitate harvest and collection, in some cases the
entire corn plant is used, including the corn stalk, corn kernels,
and in some cases even the root system of the plant.
[0104] Advantageously, no additional nutrients (other than a
nitrogen source, e.g., urea or ammonia) are required during
fermentation of corncobs or cellulosic or lignocellulosic materials
containing significant amounts of corncobs.
[0105] Corncobs, before and after comminution, are also easier to
convey and disperse, and have a lesser tendency to form explosive
mixtures in air than other cellulosic or lignocellulosic materials
such as hay and grasses.
[0106] Cellulosic materials include, for example, paper, paper
products, paper waste, paper pulp, pigmented papers, loaded papers,
coated papers, filled papers, magazines, printed matter (e.g.,
books, catalogs, manuals, labels, calendars, greeting cards,
brochures, prospectuses, newsprint), printer paper, polycoated
paper, card stock, cardboard, paperboard, materials having a high
.alpha.-cellulose content such as cotton, and mixtures of any of
these. For example paper products as described in U.S. application
Ser. No. 13/396,365 ("Magazine Feedstocks" by Medoff et al., filed
Feb. 14, 2012), the full disclosure of which is incorporated herein
by reference.
[0107] Cellulosic materials can also include lignocellulosic
materials which have been partially or fully de-lignified.
[0108] In some instances other biomass materials can be utilized,
for example starchy materials. Starchy materials include starch
itself, e.g., corn starch, wheat starch, potato starch or rice
starch, a derivative of starch, or a material that includes starch,
such as an edible food product or a crop. For example, the starchy
material can be arracacha, buckwheat, banana, barley, cassava,
kudzu, oca, sago, sorghum, regular household potatoes, sweet
potato, taro, yams, or one or more beans, such as favas, lentils or
peas. Blends of any two or more starchy materials are also starchy
materials. Mixtures of starchy, cellulosic and or lignocellulosic
materials can also be used. For example, a biomass can be an entire
plant, a part of a plant or different parts of a plant, e.g., a
wheat plant, cotton plant, a corn plant, rice plant or a tree. The
starchy materials can be treated by any of the methods described
herein.
[0109] Microbial materials that can be used as feedstock can
include, but are not limited to, any naturally occurring or
genetically modified microorganism or organism that contains or is
capable of providing a source of carbohydrates (e.g., cellulose),
for example, protists, e.g., animal protists (e.g., protozoa such
as flagellates, amoeboids, ciliates, and sporozoa) and plant
protists (e.g., algae such alveolates, chlorarachniophytes,
cryptomonads, euglenids, glaucophytes, haptophytes, red algae,
stramenopiles, and viridaeplantae). Other examples include seaweed,
plankton (e.g., macroplankton, mesoplankton, microplankton,
nanoplankton, picoplankton, and femtoplankton), phytoplankton,
bacteria (e.g., gram positive bacteria, gram negative bacteria, and
extremophiles), yeast and/or mixtures of these. In some instances,
microbial biomass can be obtained from natural sources, e.g., the
ocean, lakes, bodies of water, e.g., salt water or fresh water, or
on land. Alternatively or in addition, microbial biomass can be
obtained from culture systems, e.g., large scale dry and wet
culture and fermentation systems.
[0110] In other embodiments, the biomass materials, such as
cellulosic, starchy and lignocellulosic feedstock materials, can be
obtained from transgenic microorganisms and plants that have been
modified with respect to a wild type variety. Such modifications
may be, for example, through the iterative steps of selection and
breeding to obtain desired traits in a plant. Furthermore, the
plants can have had genetic material removed, modified, silenced
and/or added with respect to the wild type variety. For example,
genetically modified plants can be produced by recombinant DNA
methods, where genetic modifications include introducing or
modifying specific genes from parental varieties, or, for example,
by using transgenic breeding wherein a specific gene or genes are
introduced to a plant from a different species of plant and/or
bacteria. Another way to create genetic variation is through
mutation breeding wherein new alleles are artificially created from
endogenous genes. The artificial genes can be created by a variety
of ways including treating the plant or seeds with, for example,
chemical mutagens (e.g., using alkylating agents, epoxides,
alkaloids, peroxides, formaldehyde), irradiation (e.g., X-rays,
gamma rays, neutrons, beta particles, alpha particles, protons,
deuterons, UV radiation) and temperature shocking or other external
stressing and subsequent selection techniques. Other methods of
providing modified genes is through error prone PCR and DNA
shuffling followed by insertion of the desired modified DNA into
the desired plant or seed. Methods of introducing the desired
genetic variation in the seed or plant include, for example, the
use of a bacterial carrier, biolistics, calcium phosphate
precipitation, electroporation, gene splicing, gene silencing,
lipofection, microinjection and viral carriers. Additional
genetically modified materials have been described in U.S.
application Ser. No. 13/396,369 filed Feb. 14, 2012 the full
disclosure of which is incorporated herein by reference.
[0111] Any of the methods described herein can be practiced with
mixtures of any biomass materials described herein.
Other Materials
[0112] Other materials (e.g., natural or synthetic materials), for
example polymers, can be treated and/or made utilizing the methods,
equipment and systems described herein. For example polyethylene
(e.g., linear low density ethylene and high density polyethylene),
polystyrenes, sulfonated polystyenes, poly (vinyl chloride),
polyesters (e.g., nylons, DACRON.TM., KODEL.TM.), polyalkylene
esters, poly vinyl esters, polyamides (e.g., KEVLAR.TM.),
polyethylene terephthalate, cellulose acetate, acetal, poly
acrylonitrile, polycarbonates (e.g., LEXAN.TM.), acrylics [e.g.,
poly (methyl methacrylate), poly(methyl methacrylate),
polyacrylnitriles], Poly urethanes, polypropylene, poly butadiene,
polyisobutylene, polyacrylonitrile, polychloroprene (e.g.
neoprene), poly(cis-1,4-isoprene) [e.g., natural rubber],
poly(trans-1,4-isoprene) [e.g., gutta percha], phenol formaldehyde,
melamine formaldehyde, epoxides, polyesters, poly amines,
polycarboxylic acids, polylactic acids, polyvinyl alcohols,
polyanhydrides, poly fluoro carbons (e.g., TEFLON.TM.), silicons
(e.g., silicone rubber), polysilanes, poly ethers (e.g.,
polyethylene oxide, polypropylene oxide), waxes, oils and mixtures
of these. Also included are plastics, rubbers, elastomers, fibers,
waxes, gels, oils, adhesives, thermoplastics, thermosets,
biodegradable polymers, resins made with these polymers, other
polymers, other materials and combinations thereof. The polymers
can be made by any useful method including cationic polymerization,
anionic polymerization, radical polymerization, metatheses
polymerization, ring opening polymerization, graft polymerization,
addition polymerization. In some cases the treatments disclosed
herein can be used, for example, for radically initiated graft
polymerization and cross linking. Composites of polymers, for
example with glass, metals, biomass (e.g., fibers, particles),
ceramics can also be treated and/or made.
[0113] Other materials that can be treated by using the methods,
systems and equipment disclosed herein are ceramic materials,
minerals, metals, inorganic compounds. For example, silicon and
germanium crystals, silicon nitrides, metal oxides, semiconductors,
insulators, cements and or conductors.
[0114] In addition, manufactured multipart or shaped materials
(e.g., molded, extruded, welded, riveted, layered or combined in
any way) can be treated, for example cables, pipes, boards,
enclosures, integrated semiconductor chips, circuit boards, wires,
tires, windows, laminated materials, gears, belts, machines,
combinations of these. For example, treating a material by the
methods described herein can modify the surfaces, for example,
making them susceptible to further functionalization, combinations
(e.g., welding) and/or treatment can cross link the materials.
Biomass Material Preparation
Mechanical Treatments
[0115] The biomass can be in a dry form, for example with less than
about 35% moisture content (e.g., less than about 20%, less than
about 15%, less than about 10% less than about 5%, less than about
4%, less than about 3%, less than about 2% or even less than about
1%). The biomass can also be delivered in a wet state, for example
as a wet solid, a slurry or a suspension with at least about 10 wt.
% solids (e.g., at least about 20 wt. %, at least about 30 wt. %,
at least about 40 wt. %, at least about 50 wt. %, at least about 60
wt. %, at least about 70 wt. %).
[0116] The material to be processed, e.g., biomass material or
another feedstock, can be a particulate material. For example, with
an average particle size above at least about 0.25 mm (e.g., at
least about 0.5 mm, at least about 0.75 mm, at least about 1.00 mm)
and below about 10 mm (e.g., below about 6 mm, below about 5 mm,
below about 4 mm, below about 3 mm, below about 2 mm). In some
embodiments this is produced by mechanical means, for example as
described herein.
[0117] The processes disclosed herein can utilize low bulk density
materials, for example cellulosic or lignocellulosic feedstocks
that have been physically pretreated to have a bulk density of less
than about 0.75 g/cm.sup.3, e.g., less than about 0.7, 0.65, 0.60,
0.50, 0.35, 0.25, 0.20, 0.15, 0.10, 0.05 or less, e.g., less than
about 0.025 g/cm.sup.3. Bulk density is determined using ASTM
D1895B. Briefly, the method involves filling a measuring cylinder
of known volume with a sample and obtaining a weight of the sample.
The bulk density is calculated by dividing the weight of the sample
in grams by the known volume of the cylinder in cubic centimeters.
If desired, low bulk density materials can be densified, for
example, by methods described in U.S. Pat. No. 7,971,809 published
Jul. 5, 2011, the entire disclosure of which is hereby incorporated
by reference.
[0118] In some cases, the pre-treatment processing includes
screening of the biomass material. Screening can be through a mesh
or perforated plate with a desired opening size, for example, less
than about 6.35 mm (1/4 inch, 0.25 inch), (e.g., less than about
3.18 mm (1/8 inch, 0.125 inch), less than about 1.59 mm ( 1/16
inch, 0.0625 inch), is less than about 0.79 mm ( 1/32 inch, 0.03125
inch), e.g., less than about 0.51 mm ( 1/50 inch, 0.02000 inch),
less than about 0.40 mm ( 1/64 inch, 0.015625 inch), less than
about 0.23 mm (0.009 inch), less than about 0.20 mm ( 1/128 inch,
0.0078125 inch), less than about 0.18 mm (0.007 inch), less than
about 0.13 mm (0.005 inch), or even less than about 0.10 mm ( 1/256
inch, 0.00390625 inch)). In one configuration the desired biomass
falls through the perforations or screen and thus biomass larger
than the perforations or screen are not irradiated. These larger
materials can be re-processed, for example by comminuting, or they
can simply be removed from processing. In another configuration
material that is larger than the perforations is irradiated and the
smaller material is removed by the screening process or recycled.
In this kind of a configuration, the conveyor, such as a vibratory
conveyor, itself (for example a part of the conveyor) can be
perforated or made with a mesh. For example, in one particular
embodiment the biomass material may be wet and the perforations or
mesh allow water to drain away from the biomass before
irradiation.
[0119] Screening of material can also be by a manual method, for
example by an operator or mechanoid (e.g., a robot equipped with a
color, reflectivity or other sensor) that removes unwanted
material. Screening can also be by magnetic screening wherein a
magnet is disposed near the conveyed material and the magnetic
material is removed magnetically.
[0120] Optional pre-treatment processing can include heating the
material. For example a portion of a conveyor conveying the biomass
or other material can be sent through a heated zone. The heated
zone can be created, for example, by IR radiation, microwaves,
combustion (e.g., gas, coal, oil, biomass), resistive heating
and/or inductive coils. The heat can be applied from at least one
side or more than one side, can be continuous or periodic and can
be for only a portion of the material or all the material. For
example, a portion of the conveying trough can be heated by use of
a heating jacket. Heating can be, for example, for the purpose of
drying the material. In the case of drying the material, this can
also be facilitated, with or without heating, by the movement of a
gas (e.g., air, oxygen, nitrogen, He, CO.sub.2, Argon) over and/or
through the biomass as it is being conveyed.
[0121] Optionally, pre-treatment processing can include cooling the
material. Cooling material is described in U.S. Pat. No. 7,900,857
published Mar. 8, 2011, the disclosure of which in incorporated
herein by reference. For example, cooling can be by supplying a
cooling fluid, for example water (e.g., with glycerol), or nitrogen
(e.g., liquid nitrogen) to the bottom of the conveying trough.
Alternatively, a cooling gas, for example, chilled nitrogen can be
blown over the biomass materials or under the conveying system.
[0122] Another optional pre-treatment processing method can include
adding a material to the biomass or other feedstocks. The
additional material can be added by, for example, by showering,
sprinkling and or pouring the material onto the biomass as it is
conveyed. Materials that can be added include, for example, metals,
ceramics and/or ions as described in U.S. Pat. App. Pub.
2010/0105119 A1 (filed Oct. 26, 2009) and U.S. Pat. App. Pub.
2010/0159569 A1 (filed Dec. 16, 2009), the entire disclosures of
which are incorporated herein by reference. Optional materials that
can be added include acids and bases. Other materials that can be
added are oxidants (e.g., peroxides, chlorates), polymers,
polymerizable monomers (e.g., containing unsaturated bonds), water,
catalysts, enzymes and/or organisms. Materials can be added, for
example, in pure form, as a solution in a solvent (e.g., water or
an organic solvent) and/or as a solution. In some cases the solvent
is volatile and can be made to evaporate e.g., by heating and/or
blowing gas as previously described. The added material may form a
uniform coating on the biomass or be a homogeneous mixture of
different components (e.g., biomass and additional material). The
added material can modulate the subsequent irradiation step by
increasing the efficiency of the irradiation, damping the
irradiation or changing the effect of the irradiation (e.g., from
electron beams to X-rays or heat). The method may have no impact on
the irradiation but may be useful for further downstream
processing. The added material may help in conveying the material,
for example, by lowering dust levels.
[0123] Biomass can be delivered to conveyor (e.g., vibratory
conveyors that can be used in the vaults herein described) by a
belt conveyor, a pneumatic conveyor, a screw conveyor, a hopper, a
pipe, manually or by a combination of these. The biomass can, for
example, be dropped, poured and/or placed onto the conveyor by any
of these methods. In some embodiments the material is delivered to
the conveyor using an enclosed material distribution system to help
maintain a low oxygen atmosphere and/or control dust and fines.
Lofted or air suspended biomass fines and dust are undesirable
because these can form an explosion hazard or damage the window
foils of an electron gun (if such a device is used for treating the
material).
[0124] The material can be leveled to form a uniform thickness
between about 0.0312 and 5 inches (e.g., between about 0.0625 and
2.000 inches, between about 0.125 and 1 inches, between about 0.125
and 0.5 inches, between about 0.3 and 0.9 inches, between about 0.2
and 0.5 inches between about 0.25 and 1.0 inches, between about
0.25 and 0.5 inches, 0.100+/-0.025 inches, 0.150+/-0.025 inches,
0.200+/-0.025 inches, 0.250+/-0.025 inches, 0.300+/-0.025 inches,
0.350+/-0.025 inches, 0.400+/-0.025 inches, 0.450+/-0.025 inches,
0.500+/-0.025 inches, 0.550+/-0.025 inches, 0.600+/-0.025 inches,
0.700+/-0.025 inches, 0.750+/-0.025 inches, 0.800+/-0.025 inches,
0.850+/-0.025 inches, 0.900+/-0.025 inches, 0.900+/-0.025
inches.
[0125] Generally, it is preferred to convey the material as quickly
as possible through the electron beam to maximize throughput. For
example the material can be conveyed at rates of at least 1 ft/min,
e.g., at least 2 ft/min, at least 3 ft/min, at least 4 ft/min, at
least 5 ft/min, at least 10 ft/min, at least 15 ft/min, 20, 25, 30,
35, 40, 45, 50 ft/min. The rate of conveying is related to the beam
current, for example, for a 1/4 inch thick biomass and 100 mA, the
conveyor can move at about 20 ft/min to provide a useful
irradiation dosage, at 50 mA the conveyor can move at about 10
ft/min to provide approximately the same irradiation dosage.
[0126] After the biomass material has been conveyed through the
radiation zone, optional post-treatment processing can be done. The
optional post-treatment processing can, for example, be a process
described with respect to the pre-irradiation processing. For
example, the biomass can be screened, heated, cooled, and/or
combined with additives. Uniquely to post-irradiation, quenching of
the radicals can occur, for example, quenching of radicals by the
addition of fluids or gases (e.g., oxygen, nitrous oxide, ammonia,
liquids), using pressure, heat, and/or the addition of radical
scavengers. For example, the biomass can be conveyed out of the
enclosed conveyor and exposed to a gas (e.g., oxygen) where it is
quenched, forming carboxylated groups. In one embodiment the
biomass is exposed during irradiation to the reactive gas or fluid.
Quenching of biomass that has been irradiated is described in U.S.
Pat. No. 8,083,906 published Dec. 27, 2011, the entire disclosure
of which is incorporate herein by reference.
[0127] If desired, one or more mechanical treatments can be used in
addition to irradiation to further reduce the recalcitrance of the
carbohydrate-containing material. These processes can be applied
before, during and or after irradiation.
[0128] In some cases, the mechanical treatment may include an
initial preparation of the feedstock as received, e.g., size
reduction of materials, such as by comminution, e.g., cutting,
grinding, shearing, pulverizing or chopping. For example, in some
cases, loose feedstock (e.g., recycled paper, starchy materials, or
switchgrass) is prepared by shearing or shredding. Mechanical
treatment may reduce the bulk density of the
carbohydrate-containing material, increase the surface area of the
carbohydrate-containing material and/or decrease one or more
dimensions of the carbohydrate-containing material.
[0129] Alternatively, or in addition, the feedstock material can be
treated with another treatment, for example chemical treatments,
such as with an acid (HCl, H.sub.2SO.sub.4, H.sub.3PO.sub.4), a
base (e.g., KOH and NaOH), a chemical oxidant (e.g., peroxides,
chlorates, ozone), irradiation, steam explosion, pyrolysis,
sonication, oxidation, chemical treatment. The treatments can be in
any order and in any sequence and combinations. For example, the
feedstock material can first be physically treated by one or more
treatment methods, e.g., chemical treatment including and in
combination with acid hydrolysis (e.g., utilizing HCl,
H.sub.2SO.sub.4, H.sub.3PO.sub.4), radiation, sonication,
oxidation, pyrolysis or steam explosion, and then mechanically
treated. This sequence can be advantageous since materials treated
by one or more of the other treatments, e.g., irradiation or
pyrolysis, tend to be more brittle and, therefore, it may be easier
to further change the structure of the material by mechanical
treatment. As another example, a feedstock material can be conveyed
through ionizing radiation using a conveyor as described herein and
then mechanically treated. Chemical treatment can remove some or
all of the lignin (for example, chemical pulping) and can partially
or completely hydrolyze the material. The methods also can be used
with pre-hydrolyzed material. The methods also can be used with
material that has not been pre hydrolyzed The methods can be used
with mixtures of hydrolyzed and non-hydrolyzed materials, for
example, with about 50% or more non-hydrolyzed material, with about
60% or more non-hydrolyzed material, with about 70% or more
non-hydrolyzed material, with about 80% or more non-hydrolyzed
material or even with 90% or more non-hydrolyzed material.
[0130] In addition to size reduction, which can be performed
initially and/or later in processing, mechanical treatment can also
be advantageous for "opening up," "stressing," breaking or
shattering the carbohydrate-containing materials, making the
cellulose of the materials more susceptible to chain scission
and/or disruption of crystalline structure during the physical
treatment.
[0131] Methods of mechanically treating the carbohydrate-containing
material include, for example, milling or grinding. Milling may be
performed using, for example, a hammer mill, ball mill, colloid
mill, conical or cone mill, disk mill, edge mill, Wiley mill, grist
mill or other mill. Grinding may be performed using, for example, a
cutting/impact type grinder. Some exemplary grinders include stone
grinders, pin grinders, coffee grinders, and burr grinders.
Grinding or milling may be provided, for example, by a
reciprocating pin or other element, as is the case in a pin mill.
Other mechanical treatment methods include mechanical ripping or
tearing, other methods that apply pressure to the fibers, and air
attrition milling. Suitable mechanical treatments further include
any other technique that continues the disruption of the internal
structure of the material that was initiated by the previous
processing steps.
[0132] Mechanical feed preparation systems can be configured to
produce streams with specific characteristics such as, for example,
specific maximum sizes, specific length-to-width, or specific
surface areas ratios. Physical preparation can increase the rate of
reactions, improve the movement of material on a conveyor, improve
the irradiation profile of the material, improve the radiation
uniformity of the material, or reduce the processing time required
by opening up the materials and making them more accessible to
processes and/or reagents, such as reagents in a solution.
[0133] The bulk density of feedstocks can be controlled (e.g.,
increased). In some situations, it can be desirable to prepare a
low bulk density material, e.g., by densifying the material (e.g.,
densification can make it easier and less costly to transport to
another site) and then reverting the material to a lower bulk
density state (e.g., after transport). The material can be
densified, for example from less than about 0.2 g/cc to more than
about 0.9 g/cc (e.g., less than about 0.3 to more than about 0.5
g/cc, less than about 0.3 to more than about 0.9 g/cc, less than
about 0.5 to more than about 0.9 g/cc, less than about 0.3 to more
than about 0.8 g/cc, less than about 0.2 to more than about 0.5
g/cc). For example, the material can be densified by the methods
and equipment disclosed in U.S. Pat. No. 7,932,065 to Medoff and
International Publication No. WO 2008/073186 (which was filed Oct.
26, 2007, was published in English, and which designated the United
States), the full disclosures of which are incorporated herein by
reference. Densified materials can be processed by any of the
methods described herein, or any material processed by any of the
methods described herein can be subsequently densified.
[0134] In some embodiments, the material to be processed is in the
form of a fibrous material that includes fibers provided by
shearing a fiber source. For example, the shearing can be performed
with a rotary knife cutter.
[0135] For example, a fiber source, e.g., that is recalcitrant or
that has had its recalcitrance level reduced, can be sheared, e.g.,
in a rotary knife cutter, to provide a first fibrous material. The
first fibrous material is passed through a first screen, e.g.,
having an average opening size of 1.59 mm or less ( 1/16 inch,
0.0625 inch), provide a second fibrous material. If desired, the
fiber source can be cut prior to the shearing, e.g., with a
shredder. For example, when a paper is used as the fiber source,
the paper can be first cut into strips that are, e.g., 1/4- to
1/2-inch wide, using a shredder, e.g., a counter-rotating screw
shredder, such as those manufactured by Munson (Utica, N.Y.). As an
alternative to shredding, the paper can be reduced in size by
cutting to a desired size using a guillotine cutter. For example,
the guillotine cutter can be used to cut the paper into sheets that
are, e.g., 10 inches wide by 12 inches long.
[0136] In some embodiments, the shearing of the fiber source and
the passing of the resulting first fibrous material through a first
screen are performed concurrently. The shearing and the passing can
also be performed in a batch-type process.
[0137] For example, a rotary knife cutter can be used to
concurrently shear the fiber source and screen the first fibrous
material. A rotary knife cutter includes a hopper that can be
loaded with a shredded fiber source prepared by shredding a fiber
source.
[0138] In some implementations, the feedstock is physically treated
prior to saccharification and/or fermentation. Physical treatment
processes can include one or more of any of those described herein,
such as mechanical treatment, chemical treatment, irradiation,
sonication, oxidation, pyrolysis or steam explosion. Treatment
methods can be used in combinations of two, three, four, or even
all of these technologies (in any order). When more than one
treatment method is used, the methods can be applied at the same
time or at different times. Other processes that change a molecular
structure of a biomass feedstock may also be used, alone or in
combination with the processes disclosed herein.
[0139] Mechanical treatments that may be used, and the
characteristics of the mechanically treated carbohydrate-containing
materials, are described in further detail in U.S. Pat. App. Pub.
2012/0100577 A1, filed Oct. 18, 2011, the full disclosure of which
is hereby incorporated herein by reference.
Sonication, Pyrolysis, Oxidation, Steam Explosion, Heating
[0140] If desired, one or more sonication, pyrolysis, oxidative,
heating or steam explosion processes can be used instead of or in
addition to irradiation to reduce or further reduce the
recalcitrance of the carbohydrate-containing material. For example,
these processes can be applied before, during and or after
irradiation. Some of these processes are described in detail in
U.S. Pat. No. 7,932,065 to Medoff, the full disclosure of which is
incorporated herein by reference.
[0141] Alternatively, the biomass can be heated after the biomass
is treated by one or more of sonication, pyrolysis, oxidation,
radiation and steam explosion processes. For example the biomass
can be heated after the biomass is irradiated prior to a
saccharification step. The heating can be created, for example, by
IR radiation, microwaves, combustion (e.g., gas, coal, oil, and/or
biomass), resistive heating and/or inductive coils. This heating
can be in a liquid, for example, in water or other water-based
solvents. The heat can be applied from at least one side or more
than one side, can be continuous or periodic and can be for only a
portion of the material or all the material. The biomass can be
heated to temperatures above about 90 deg C. in an aqueous liquid
that may have an acid or a base present. For example, the aqueous
biomass slurry can be heated to between about 90 and 150 deg C.
(e.g., between about 105-145 deg C., between about 110 to 140 deg
C., or 115-135 deg C.). The time that the aqueous biomass mixture
is held at the targeted temperature range is 1 to 12 hours (e.g., 1
to 6 hours, 1 to 4 hours). In some instances, the aqueous biomass
mixture is alkaline and the pH is between 6 and 13 (e.g., 8-12, or
8-11).
Intermediates and Products
[0142] Using the processes described herein, the biomass material
can be converted to one or more products, such as energy, fuels,
foods and materials. For example, intermediates and products such
as organic acids, salts of organic acids, anhydrides, esters of
organic acids and fuels, e.g., fuels for internal combustion
engines or feedstocks for fuel cells can be produced. Systems and
processes are described herein that can use as feedstock cellulosic
and/or lignocellulosic materials that are readily available, but
often can be difficult to process, e.g., municipal waste streams
and waste paper streams, such as streams that include newspaper,
Kraft paper, corrugated paper or mixtures of these.
[0143] Specific examples of products include, but are not limited
to, hydrogen, sugars (e.g., glucose, xylose, arabinose, mannose,
galactose, fructose, disaccharides, oligosaccharides and
polysaccharides), alcohols (e.g., monohydric alcohols or dihydric
alcohols, such as ethanol, n-propanol, isobutanol, sec-butanol,
tert-butanol or n-butanol), hydrated or hydrous alcohols (e.g.,
containing greater than 10%, 20%, 30% or even greater than 40%
water), biodiesel, organic acids, hydrocarbons (e.g., methane,
ethane, propane, isobutene, pentane, n-hexane, biodiesel,
bio-gasoline and mixtures thereof), co-products (e.g., proteins,
such as cellulolytic proteins (enzymes) or single cell proteins),
and mixtures of any of these in any combination or relative
concentration, and optionally in combination with any additives
(e.g., fuel additives). Other examples include carboxylic acids,
salts of a carboxylic acid, a mixture of carboxylic acids and salts
of carboxylic acids and esters of carboxylic acids (e.g., methyl,
ethyl and n-propyl esters), ketones (e.g., acetone), aldehydes
(e.g., acetaldehyde), alpha and beta unsaturated acids (e.g.,
acrylic acid) and olefins (e.g., ethylene). Other alcohols and
alcohol derivatives include propanol, propylene glycol,
1,4-butanediol, 1,3-propanediol, sugar alcohols (e.g., erythritol,
glycol, glycerol, sorbitol threitol, arabitol, ribitol, mannitol,
dulcitol, fucitol, iditol, isomalt, maltitol, lactitol, xylitol and
other polyols), and methyl or ethyl esters of any of these
alcohols. Other products include methyl acrylate,
methylmethacrylate, D-lactic acid, L-lactic acid, pyruvic acid,
poly lactic acid, citric acid, formic acid, acetic acid, propionic
acid, butyric acid, succinic acid, valeric acid, caproic acid,
3-hydroxypropionic acid, palmitic acid, stearic acid, oxalic acid,
malonic acid, glutaric acid, oleic acid, linoleic acid, glycolic
acid, gamma-hydroxybutyric acid, and mixtures thereof, salts of any
of these acids, mixtures of any of the acids and their respective
salts.
[0144] Any combination of the above products with each other,
and/or of the above products with other products, which other
products may be made by the processes described herein or
otherwise, may be packaged together and sold as products. The
products may be combined, e.g., mixed, blended or co-dissolved, or
may simply be packaged or sold together.
[0145] Any of the products or combinations of products described
herein may be sanitized or sterilized prior to selling the
products, e.g., after purification or isolation or even after
packaging, to neutralize one or more potentially undesirable
contaminants that could be present in the product(s). Such
sanitation can be done with electron bombardment, for example, by
at a dosage of less than about 20 Mrad, e.g., from about 0.1 to 15
Mrad, from about 0.5 to 7 Mrad, or from about 1 to 3 Mrad.
[0146] The processes described herein can produce various
by-product streams useful for generating steam and electricity to
be used in other parts of the plant (co-generation) or sold on the
open market. For example, steam generated from burning by-product
streams can be used in a distillation process. As another example,
electricity generated from burning by-product streams can be used
to power electron beam generators used in pretreatment.
[0147] The by-products used to generate steam and electricity are
derived from a number of sources throughout the process. For
example, anaerobic digestion of wastewater can produce a biogas
high in methane and a small amount of waste biomass (sludge). As
another example, post-saccharification and/or post-distillate
solids (e.g., unconverted lignin, cellulose, and hemicellulose
remaining from the pretreatment and primary processes) can be used,
e.g., burned, as a fuel.
[0148] Other intermediates and products, including food and
pharmaceutical products, are described in U.S. Pat. App. Pub.
2010/0124583 A1, published May 20, 2010, to Medoff, the full
disclosure of which is hereby incorporated by reference herein.
Lignin Derived Products
[0149] The spent biomass (e.g., spent lignocellulosic material)
from lignocellulosic processing by the methods described are
expected to have a high lignin content and in addition to being
useful for producing energy through combustion in a Co-Generation
plant, may have uses as other valuable products. For example, the
lignin can be used as captured as a plastic, or it can be
synthetically upgraded to other plastics. In some instances, it can
also be converted to lignosulfonates, which can be utilized as
binders, dispersants, emulsifiers or as sequestrants.
[0150] When used as a binder, the lignin or a lignosulfonate can,
e.g., be utilized in coal briquettes, in ceramics, for binding
carbon black, for binding fertilizers and herbicides, as a dust
suppressant, in the making of plywood and particle board, for
binding animal feeds, as a binder for fiberglass, as a binder in
linoleum paste and as a soil stabilizer.
[0151] When used as a dispersant, the lignin or lignosulfonates can
be used, e.g., concrete mixes, clay and ceramics, dyes and
pigments, leather tanning and in gypsum board.
[0152] When used as an emulsifier, the lignin or lignosulfonates
can be used, e.g., in asphalt, pigments and dyes, pesticides and
wax emulsions.
[0153] When used as a sequestrant, the lignin or lignosulfonates
can be used, e.g., in micro-nutrient systems, cleaning compounds
and water treatment systems, e.g., for boiler and cooling
systems.
[0154] For energy production lignin generally has a higher energy
content than holocellulose (cellulose and hemicellulose) since it
contains more carbon than homocellulose. For example, dry lignin
can have an energy content of between about 11,000 and 12,500 BTU
per pound, compared to 7,000 an 8,000 BTU per pound of
holocellulose. As such, lignin can be densified and converted into
briquettes and pellets for burning. For example, the lignin can be
converted into pellets by any method described herein. For a slower
burning pellet or briquette, the lignin can be crosslinked, such as
applying a radiation dose of between about 0.5 Mrad and 5 Mrad.
Crosslinking can make a slower burning form factor. The form
factor, such as a pellet or briquette, can be converted to a
"synthetic coal" or charcoal by pyrolyzing in the absence of air,
e.g., at between 400 and 950.degree. C. Prior to pyrolyzing, it can
be desirable to crosslink the lignin to maintain structural
integrity.
Saccharification
[0155] In order to convert the feedstock to a form that can be
readily processed the glucan- or xylan-containing cellulose in the
feedstock can be hydrolyzed to low molecular weight carbohydrates,
such as sugars, by a saccharifying agent, e.g., an enzyme or acid,
a process referred to as saccharification. The low molecular weight
carbohydrates can then be used, for example, in an existing
manufacturing plant, such as a single cell protein plant, an enzyme
manufacturing plant, or a fuel plant, e.g., an ethanol
manufacturing facility.
[0156] The feedstock can be hydrolyzed using an enzyme, e.g., by
combining the materials and the enzyme in a solvent, e.g., in an
aqueous solution.
[0157] Alternatively, the enzymes can be supplied by organisms that
break down biomass, such as the cellulose and/or the lignin
portions of the biomass, contain or manufacture various
cellulolytic enzymes (cellulases), ligninases or various small
molecule biomass-degrading metabolites. These enzymes may be a
complex of enzymes that act synergistically to degrade crystalline
cellulose or the lignin portions of biomass. Examples of
cellulolytic enzymes include: endoglucanases, cellobiohydrolases,
and cellobiases (beta-glucosidases).
[0158] During saccharification a cellulosic substrate can be
initially hydrolyzed by endoglucanases at random locations
producing oligomeric intermediates. These intermediates are then
substrates for exo-splitting glucanases such as cellobiohydrolase
to produce cellobiose from the ends of the cellulose polymer.
Cellobiose is a water-soluble 1,4-linked dimer of glucose. Finally,
cellobiase cleaves cellobiose to yield glucose. The efficiency
(e.g., time to hydrolyze and/or completeness of hydrolysis) of this
process depends on the recalcitrance of the cellulosic
material.
[0159] Therefore, the treated biomass materials can be
saccharified, by combining the material and a cellulase enzyme in a
fluid medium, e.g., an aqueous solution. In some cases, the
material is boiled, steeped, or cooked in hot water prior to
saccharification, as described in U.S. Pat. App. Pub. 2012/0100577
A1 by Medoff and Masterman, published on Apr. 26, 2012, the entire
contents of which are incorporated herein.
[0160] The saccharification process can be partially or completely
performed in a tank (e.g., a tank having a volume of at least 4000,
40,000, or 500,000 L) in a manufacturing plant, and/or can be
partially or completely performed in transit, e.g., in a rail car,
tanker truck, or in a supertanker or the hold of a ship. The time
required for complete saccharification will depend on the process
conditions and the carbohydrate-containing material and enzyme
used. If saccharification is performed in a manufacturing plant
under controlled conditions, the cellulose may be substantially
entirely converted to sugar, e.g., glucose in about 12-96 hours. If
saccharification is performed partially or completely in transit,
saccharification may take longer.
[0161] It is generally preferred that the tank contents be mixed
during saccharification, e.g., using jet mixing as described in
International App. No. PCT/US2010/035331, filed May 18, 2010, which
was published in English as WO 2010/135380 and designated the
United States, the full disclosure of which is incorporated by
reference herein.
[0162] The addition of surfactants can enhance the rate of
saccharification. Examples of surfactants include non-ionic
surfactants, such as a TWEEN.RTM. 20 or TWEEN.RTM. 80 polyethylene
glycol surfactants, ionic surfactants, or amphoteric
surfactants.
[0163] It is generally preferred that the concentration of the
sugar solution resulting from saccharification be relatively high,
e.g., greater than 40%, or greater than 50, 60, 70, 80, 90 or even
greater than 95% by weight. Water may be removed, e.g., by
evaporation, to increase the concentration of the sugar solution.
This reduces the volume to be shipped, and also inhibits microbial
growth in the solution.
[0164] Alternatively, sugar solutions of lower concentrations may
be used, in which case it may be desirable to add an antimicrobial
additive, e.g., a broad spectrum antibiotic, in a low
concentration, e.g., 50 to 150 ppm. Other suitable antibiotics
include amphotericin B, ampicillin, chloramphenicol, ciprofloxacin,
gentamicin, hygromycin B, kanamycin, neomycin, penicillin,
puromycin, streptomycin. For example, antimicrobials from Lallemand
Biofuels and Distilled Spirits (Montreal, Quebec, Canada) can be
used such as LACTOSIDE V.TM., BACTENIX.RTM. V300, BACTENIX.RTM.
V300SP, ALLPEN.TM. SPECIAL, BACTENIX.RTM. V60, BACTENIX.RTM. V60SP,
BACTENIX.RTM. V50 and/or LACTOSIDE 247.TM.. Antibiotics will
inhibit growth of microorganisms during transport and storage, and
can be used at appropriate concentrations, e.g., between 15 and
1000 ppm by weight, e.g., between 25 and 500 ppm, or between 50 and
150 ppm. If desired, an antibiotic can be included even if the
sugar concentration is relatively high. Alternatively, other
additives with anti-microbial of preservative properties may be
used. Preferably the antimicrobial additive(s) are food-grade.
[0165] A relatively high concentration solution can be obtained by
limiting the amount of water added to the carbohydrate-containing
material with the enzyme. The concentration can be controlled,
e.g., by controlling how much saccharification takes place. For
example, concentration can be increased by adding more
carbohydrate-containing material to the solution. In order to keep
the sugar that is being produced in solution, a surfactant can be
added, e.g., one of those discussed above. Solubility can also be
increased by increasing the temperature of the solution. For
example, the solution can be maintained at a temperature of
40-50.degree. C., 60-80.degree. C., or even higher.
Saccharifying Agents
[0166] Suitable cellulolytic enzymes include cellulases from
species in the genera Bacillus, Coprinus, Myceliophthora,
Cephalosporium, Scytalidium, Penicillium, Aspergillus, Pseudomonas,
Humicola, Fusarium, Thielavia, Acremonium, Chrysosporium and
Trichoderma, especially those produced by a strain selected from
the species Aspergillus (see, e.g., EP Pub. No. 0 458 162),
Humicola insolens (reclassified as Scytalidium thermophilum, see,
e.g., U.S. Pat. No. 4,435,307), Coprinus cinereus, Fusarium
oxysporum, Myceliophthora thermophila, Meripilus giganteus,
Thielavia terrestris, Acremonium sp. (including, but not limited
to, A. persicinum, A. acremonium, A. brachypenium, A.
dichromosporum, A. obclavatum, A. pinkertoniae, A. roseogriseum, A.
incoloratum, and A. furatum). Preferred strains include Humicola
insolens DSM 1800, Fusarium oxysporum DSM 2672, Myceliophthora
thermophila CBS 117.65, Cephalosporium sp. RYM-202, Acremonium sp.
CBS 478.94, Acremonium sp. CBS 265.95, Acremonium persicinum CBS
169.65, Acremonium acremonium AHU 9519, Cephalosporium sp. CBS
535.71, Acremonium brachypenium CBS 866.73, Acremonium
dichromosporum CBS 683.73, Acremonium obclavatum CBS 311.74,
Acremonium pinkertoniae CBS 157.70, Acremonium roseogriseum CBS
134.56, Acremonium incoloratum CBS 146.62, and Acremonium furatum
CBS 299.70H. Cellulolytic enzymes may also be obtained from
Chrysosporium, preferably a strain of Chrysosporium lucknowense.
Additional strains that can be used include, but are not limited
to, Trichoderma (particularly T. viride, T. reesei, and T.
koningii), alkalophilic Bacillus (see, for example, U.S. Pat. No.
3,844,890 and EP Pub. No. 0 458 162), and Streptomyces (see, e.g.,
EP Pub. No. 0 458 162).
[0167] In addition to or in combination to enzymes, acids, bases
and other chemicals (e.g., oxidants) can be utilized to saccharify
lignocellulosic and cellulosic materials. These can be used in any
combination or sequence (e.g., before, after and/or during addition
of an enzyme). For example strong mineral acids can be utilized
(e.g. HCl, H.sub.2SO.sub.4, H.sub.3PO.sub.4) and strong bases
(e.g., NaOH, KOH).
Sugars
[0168] In the processes described herein, for example after
saccharification, sugars (e.g., glucose and xylose) can be isolated
and/or purified. For example sugars can be isolated and/or purified
by precipitation, crystallization, chromatography (e.g., simulated
moving bed chromatography, high pressure chromatography),
electrodialysis, centrifugation, extraction, any other isolation
method known in the art, and combinations thereof.
Hydrogenation and Other Chemical Transformations
[0169] The processes described herein can include hydrogenation.
For example glucose and xylose can be hydrogenated to sorbitol and
xylitol respectively. Hydrogenation can be accomplished by use of a
catalyst (e.g., Pt/gamma-Al.sub.2O.sub.3, Ru/C, Raney Nickel, or
other catalysts know in the art) in combination with H.sub.2 under
high pressure (e.g., 10 to 12000 psi). Other types of chemical
transformation of the products from the processes described herein
can be used, for example production of organic sugar derived
products (e.g., furfural and furfural-derived products). Chemical
transformations of sugar derived products are described in U.S.
Ser. No. 13/934,704 filed Jul. 3, 2013, the entire disclosure of
which is incorporated herein by reference in its entirety.
Fermentation
[0170] Yeast and Zymomonas bacteria, for example, can be used for
fermentation or conversion of sugar(s) to alcohol(s). Other
microorganisms are discussed below. The optimum pH for
fermentations is about pH 4 to 7. For example, the optimum pH for
yeast is from about pH 4 to 5, while the optimum pH for Zymomonas
is from about pH 5 to 6. Typical fermentation times are about 24 to
168 hours (e.g., 24 to 96 hrs) with temperatures in the range of
20.degree. C. to 40.degree. C. (e.g., 26.degree. C. to 40.degree.
C.), however thermophilic microorganisms prefer higher
temperatures.
[0171] In some embodiments, e.g., when anaerobic organisms are
used, at least a portion of the fermentation is conducted in the
absence of oxygen, e.g., under a blanket of an inert gas such as
N.sub.2, Ar, He, CO.sub.2 or mixtures thereof. Additionally, the
mixture may have a constant purge of an inert gas flowing through
the tank during part of or all of the fermentation. In some cases,
anaerobic condition, can be achieved or maintained by carbon
dioxide production during the fermentation and no additional inert
gas is needed.
[0172] In some embodiments, all or a portion of the fermentation
process can be interrupted before the low molecular weight sugar is
completely converted to a product (e.g., ethanol). The intermediate
fermentation products include sugar and carbohydrates in high
concentrations. The sugars and carbohydrates can be isolated via
any means known in the art. These intermediate fermentation
products can be used in preparation of food for human or animal
consumption. Additionally or alternatively, the intermediate
fermentation products can be ground to a fine particle size in a
stainless-steel laboratory mill to produce a flour-like substance.
Jet mixing may be used during fermentation, and in some cases
saccharification and fermentation are performed in the same
tank.
[0173] Nutrients for the microorganisms may be added during
saccharification and/or fermentation, for example the food-based
nutrient packages described in U.S. Pat. App. Pub. 2012/0052536,
filed Jul. 15, 2011, the complete disclosure of which is
incorporated herein by reference. In some cases, the food-based
nutrient source is selected from the group consisting of grains,
vegetables, residues of grains, residues of vegetables, residues of
meat (e.g., stock, extract, bouillon or renderings), and mixtures
thereof. For example, the nutrient source may be selected from the
group consisting of wheat, oats, barley, soybeans, peas, legumes,
potatoes, corn, rice bran, corn meal, wheat bran, meat product
residues, and mixtures thereof.
[0174] "Fermentation" includes the methods and products that are
disclosed in application Nos. PCT/US2012/71093 published Jun. 27,
2013, PCT/US2012/71907 published Jun. 27, 2012, and
PCT/US2012/71083 published Jun. 27, 2012 the contents of which are
incorporated by reference herein in their entirety.
[0175] Mobile fermenters can be utilized, as described in
International App. No. PCT/US2007/074028 (which was filed Jul. 20,
2007, was published in English as WO 2008/011598 and designated the
United States) and has a U.S. Pat. No. 8,318,453, the contents of
which are incorporated herein in its entirety. Similarly, the
saccharification equipment can be mobile. Further, saccharification
and/or fermentation may be performed in part or entirely during
transit.
Fermentation Agents
[0176] The microorganism(s) used in fermentation can be
naturally-occurring microorganisms and/or engineered
microorganisms. For example, the microorganism can be a bacterium
(including, but not limited to, e.g., a cellulolytic bacterium), a
fungus, (including, but not limited to, e.g., a yeast), a plant, a
protist, e.g., a protozoa or a fungus-like protest (including, but
not limited to, e.g., a slime mold), or an alga. When the organisms
are compatible, mixtures of organisms can be utilized.
[0177] Suitable fermenting microorganisms have the ability to
convert carbohydrates, such as glucose, fructose, xylose,
arabinose, mannose, galactose, oligosaccharides or polysaccharides
into fermentation products. Fermenting microorganisms include
strains of the genus Sacchromyces spp. (including, but not limited
to, S. cerevisiae (baker's yeast), S. distaticus, S. uvarum), the
genus Kluyveromyces, (including, but not limited to, K. marxianus,
K. fragilis), the genus Candida (including, but not limited to, C.
pseudotropicalis, and C. brassicae), Pichia stipitis (a relative of
Candida shehatae), the genus Clavispora (including, but not limited
to, C. lusitaniae and C. opuntiae), the genus Pachysolen
(including, but not limited to, P. tannophilus), the genus
Bretannomyces (including, but not limited to, e.g., B. clausenii
(Philippidis, G. P., 1996, Cellulose bioconversion technology, in
Handbook on Bioethanol: Production and Utilization, Wyman, C. E.,
ed., Taylor & Francis, Washington, D.C., 179-212)). Other
suitable microorganisms include, for example, Zymomonas mobilis,
Clostridium spp. (including, but not limited to, C. thermocellum
(Philippidis, 1996, supra), C. saccharobutylacetonicum, C.
tyrobutyricum C. saccharobutylicum, C. Puniceum, C. beijernckii,
and C. acetobutylicum), Moniliella spp. (including but not limited
to M. pollinis, M. tomentosa, M. madida, M. nigrescens, M.
oedocephali, M. megachiliensis), Yarrowia lipolytica, Aureobasidium
sp., Trichosporonoides sp., Trigonopsis variabilis, Trichosporon
sp., Moniliellaacetoabutans sp., Typhula variabilis, Candida
magnoliae, Ustilaginomycetes sp., Pseudozyma tsukubaensis, yeast
species of genera Zygosaccharomyces, Debaryomyces, Hansenula and
Pichia, and fungi of the dematioid genus Torula (e.g., T.
corallina).
[0178] Additional microorganisms include the Lactobacillus group.
Examples include Lactobacillus casei, Lactobacillus rhamnosus,
Lactobacillus delbrueckii, Lactobacillus plantarum, Lactobacillus
coryniformis, e.g., Lactobacillus coryniformis subspecies torquens,
Lactobacillus pentosus, Lactobacillus brevis. Other microorganisms
include Pediococus penosaceus, Rhizopus oryzae.
[0179] Several organisms, such as bacteria, yeasts and fungi, can
be utilized to ferment biomass derived products such as sugars and
alcohols to succinic acid and similar products. For example,
organisms can be selected from; Actinobacillus succinogenes,
Anaerobiospirillum succiniciproducens, Mannheimia
succiniciproducens, Ruminococcus flaverfaciens, Ruminococcus albus,
Fibrobacter succinogenes, Bacteroides fragilis, Bacteroides
ruminicola, Bacteroides amylophilus, Bacteroides succinogenes,
Mannheimia succiniciproducens, Corynebacterium glutamicium,
Aspergillus niger, Aspergillus fumigatus, Byssochlamys nivea,
Lentinus degener, Paecilomyces varioti, Penicillium viniferum,
Saccharomyces cerevisiae, Enterococcus faecali, Prevotella
ruminicolas, Debaryomyces hansenii, Candida catenulata VKM Y-5, C.
mycoderma VKM Y-240, C. rugosa VKM Y-67, C. paludigena VKM Y-2443,
C. utilis VKM Y-74, C. utilis 766, C. zeylanoides VKM Y-6, C.
zeylanoides VKM Y-14, C. zeylanoides VKM Y-2324, C. zeylanoides VKM
Y-1543, C. zeylanoides VKM Y-2595, C. valida VKM Y-934,
Kluyveromyces wickerhamii VKM Y-589, Pichia anomala VKM Y-118, P.
besseyi VKM Y-2084, P. media VKM Y-1381, P. guilliermondii H-P-4,
P. guilliermondii 916, P. inositovora VKM Y-2494, Saccharomyces
cerevisiae VKM Y-381, Torulopsis candida 127, T. candida 420,
Yarrowia lipolytica 12a, Y. lipolytica VKM Y-47, Y. lipolytica 69,
Y. lipolytica VKM Y-57, Y. lipolytica 212, Y. lipolytica 374/4, Y.
lipolytica 585, Y. lipolytica 695, Y. lipolytica 704, and mixtures
of these organisms.
[0180] Many such microbial strains are publicly available, either
commercially or through depositories such as the ATCC (American
Type Culture Collection, Manassas, Va., USA), the NRRL
(Agricultural Research Service Culture Collection, Peoria, Ill.,
USA), or the DSMZ (Deutsche Sammlung von Mikroorganismen and
Zellkulturen GmbH, Braunschweig, Germany), to name a few.
[0181] Commercially available yeasts include, for example, RED
STAR.RTM./Lesaffre Ethanol Red (available from Red Star/Lesaffre,
USA), FALI.RTM. (available from Fleischmann's Yeast, a division of
Burns Philip Food Inc., USA), SUPERSTART.RTM. (Lallemand Biofuels
and Distilled Spirits, Canada), EAGLE C6 FUEL.TM. or C6 FUEL.TM.
(available from Lallemand Biofuels and Distilled Spirits, Canada),
GERT STRAND.RTM. (available from Gert Strand AB, Sweden) and
FERMOL.RTM. (available from DSM Specialties).
Distillation
[0182] After fermentation, the resulting fluids can be distilled
using, for example, a "beer column" to separate ethanol and other
alcohols from the majority of water and residual solids. The vapor
exiting the beer column can be, e.g., 35% by weight ethanol and can
be fed to a rectification column. A mixture of nearly azeotropic
(92.5%) ethanol and water from the rectification column can be
purified to pure (99.5%) ethanol using vapor-phase molecular
sieves. The beer column bottoms can be sent to the first effect of
a three-effect evaporator. The rectification column reflux
condenser can provide heat for this first effect. After the first
effect, solids can be separated using a centrifuge and dried in a
rotary dryer. A portion (25%) of the centrifuge effluent can be
recycled to fermentation and the rest sent to the second and third
evaporator effects. Most of the evaporator condensate can be
returned to the process as fairly clean condensate with a small
portion split off to waste water treatment to prevent build-up of
low-boiling compounds.
Hydrocarbon-Containing Materials
[0183] In other embodiments utilizing the methods and systems
described herein, hydrocarbon-containing materials can be
processed. Any process described herein can be used to treat any
hydrocarbon-containing material herein described.
"Hydrocarbon-containing materials," as used herein, is meant to
include oil sands, oil shale, tar sands, coal dust, coal slurry,
bitumen, various types of coal, and other naturally-occurring and
synthetic materials that include both hydrocarbon components and
solid matter. The solid matter can include rock, sand, clay, stone,
silt, drilling slurry, or other solid organic and/or inorganic
matter. The term can also include waste products such as drilling
waste and by-products, refining waste and by-products, or other
waste products containing hydrocarbon components, such as asphalt
shingling and covering, asphalt pavement, etc.
[0184] In yet other embodiments utilizing the methods and systems
described herein, wood and wood containing produces can be
processed. For example lumber products can be processed, e.g.
boards, sheets, laminates, beams, particle boards, composites,
rough cut wood, soft wood and hard wood. In addition cut trees,
bushes, wood chips, saw dust, roots, bark, stumps, decomposed wood
and other wood containing biomass material can be processed.
Conveying Systems
[0185] Various conveying systems can be used to convey the biomass
material, for example, as discussed, to a vault, and under an
electron beam in a vault. Exemplary conveyors are belt conveyors,
pneumatic conveyors, screw conveyors, carts, trains, trains or
carts on rails, elevators, front loaders, backhoes, cranes, various
scrapers and shovels, trucks, and throwing devices can be used. For
example, vibratory conveyors can be used in various processes
described herein. Vibratory conveyors are described in
PCT/US2013/64289 filed Oct. 10, 2013 the full disclosure of which
is incorporated by reference herein.
[0186] Vibratory conveyors are particularly useful for spreading
the material and producing a uniform layer on the conveyor trough
surface. For example the initial feedstock can form a pile of
material that can be at least four feet high (e.g., at least about
3 feet, at least about 2 feet, at least about 1 foot, at least
about 6 inches, at least about 5 inches, at least about, 4 inches,
at least about 3 inches, at least about 2 inches, at least about 1
inch, at least about 1/2 inch) and spans less than the width of the
conveyor (e.g., less than about 10%, less than about 20%, less than
about 30%, less than about 40%, less than about 50%, less than
about 60%, less than about 70%, less than about 80%, less than
about 90%, less than about 95%, less than about 99%). The vibratory
conveyor can spread the material to span the entire width of the
conveyor trough and have a uniform thickness, preferably as
discussed above. In some cases, an additional spreading method can
be useful. For example, a spreader such as a broadcast spreader, a
drop spreader (e.g., a CHRISTY SPREADER.TM.) or combinations
thereof can be used to drop (e.g., place, pour, spill and/or
sprinkle) the feedstock over a wide area. Optionally, the spreader
can deliver the biomass as a wide shower or curtain onto the
vibratory conveyor. Additionally, a second conveyor, upstream from
the first conveyor (e.g., the first conveyor is used in the
irradiation of the feedstock), can drop biomass onto the first
conveyor, where the second conveyor can have a width transverse to
the direction of conveying smaller than the first conveyor. In
particular, when the second conveyor is a vibratory conveyor, the
feedstock is spread by the action of the second and first conveyor.
In some optional embodiments, the second conveyor ends in a bias
cross cut discharge (e.g., a bias cut with a ratio of 4:1) so that
the material can be dropped as a wide curtain (e.g., wider than the
width of the second conveyor) onto the first conveyor. The initial
drop area of the biomass by the spreader (e.g., broadcast spreader,
drop spreader, conveyor, or cross cut vibratory conveyor) can span
the entire width of the first vibratory conveyor, or it can span
part of this width. Once dropped onto the conveyor, the material is
spread even more uniformly by the vibrations of the conveyor so
that, preferably, the entire width of the conveyor is covered with
a uniform layer of biomass. In some embodiments combinations of
spreaders can be used. Some methods of spreading a feed stock are
described in U.S. Pat. No. 7,153,533, filed Jul. 23, 2002 and
published Dec. 26, 2006, the entire disclosure of which is
incorporated herein by reference.
[0187] Generally, it is preferred to convey the material as quickly
as possible through an electron beam to maximize throughput. For
example, the material can be conveyed at rates of at least 1
ft/min, e.g., at least 2 ft/min, at least 3 ft/min, at least 4
ft/min, at least 5 ft/min, at least 10 ft/min, at least 15 ft/min,
at least 20 ft/min, at least 25 ft/min, at least 30 ft/min, at
least 40 ft/min, at least 50 ft/min, at least 60 ft/min, at least
70 ft/min, at least 80 ft/min, at least 90 ft/min. The rate of
conveying is related to the beam current and targeted irradiation
dose, for example, for a 1/4inch thick biomass spread over a 5.5
foot wide conveyor and 100 mA, the conveyor can move at about 20
ft/min to provide a useful irradiation dosage (e.g. about 10 Mrad
for a single pass), at 50 mA the conveyor can move at about 10
ft/min to provide approximately the same irradiation dosage.
[0188] The rate at which material can be conveyed depends on the
shape and mass of the material being conveyed, and the desired
amount. Flowing materials e.g., particulate materials, are
particularly amenable to conveying with vibratory conveyors.
Conveying speeds can, for example be, at least 100 lb/hr (e.g., at
least 500 lb/hr, at least 1000 lb/hr, at least 2000 lb/hr, at least
3000 lb/hr, at least 4000 lb/hr, at least 5000 lb/hr, at least
10,000 lb/hr, at least 15,000 lb/hr, or even at least 25,000
lb/hr). Some typical conveying speeds can be between about 1000 and
10,000 lb/hr, (e.g., between about 1000 lb/hr and 8000 lb/hr,
between about 2000 and 7000 lb/hr, between about 2000 and 6000
lb/hr, between about 2000 and 5000 lb/hr, between about 2000 and
4500 lb/hr, between about 1500 and 5000 lb/hr, between about 3000
and 7000 lb/hr, between about 3000 and 6000 lb/hr, between about
4000 and 6000 lb/hr and between about 4000 and 5000 lb/hr). Typical
conveying speeds depend on the density of the material. For
example, for a biomass with a density of about 35 lb/ft.sup.3, and
a conveying speed of about 5000 lb/hr, the material is conveyed at
a rate of about 143 ft.sup.3/hr, if the material is 1/4'' thick and
is in a trough 5.5 ft wide, the material is conveyed at a rate of
about 1250 ft/hr (about 21 ft/min). Rates of conveying the material
can therefore vary greatly. Preferably, for example, a 1/4'' thick
layer of biomass, is conveyed at speeds of between about 5 and 100
ft/min (e.g. between about 5 and 100 ft/min, between about 6 and
100 ft/min, between about 7 and 100 ft/min, between about 8 and 100
ft/min, between about 9 and 100 ft/min, between about 10 and 100
ft/min, between about 11 and 100 ft/min, between about 12 and 100
ft/min, between about 13 and 100 ft/min, between about 14 and 100
ft/min, between about 15 and 100 ft/min, between about 20 and 100
ft/min, between about 30 and 100 ft/min, between about 40 and 100
ft/min, between about 2 and 60 ft/min, between about 3 and 60
ft/min, between about 5 and 60 ft/min, between about 6 and 60
ft/min, between about 7 and 60 ft/min, between about 8 and 60
ft/min, between about 9 and 60 ft/min, between about 10 and 60
ft/min, between about 15 and 60 ft/min, between about 20 and 60
ft/min, between about 30 and 60 ft/min, between about 40 and 60
ft/min, between about 2 and 50 ft/min, between about 3 and 50
ft/min, between about 5 and 50 ft/min, between about 6 and 50
ft/min, between about 7 and 50 ft/min, between about 8 and 50
ft/min, between about 9 and 50 ft/min, between about 10 and 50
ft/min, between about 15 and 50 ft/min, between about 20 and 50
ft/min, between about 30 and 50 ft/min, between about 40 and 50
ft/min). It is preferable that the material be conveyed at a
constant rate, for example, to help maintain a constant irradiation
of the material as it passes under the electron beam (e.g., shower,
field).
[0189] The vibratory conveyors described can include screens used
for sieving and sorting materials. Port openings on the side or
bottom of the troughs can be used for sorting, selecting or
removing specific materials, for example, by size or shape. Some
conveyors have counterbalances to reduce the dynamic forces on the
support structure. Some vibratory conveyors are configured as
spiral elevators, are designed to curve around surfaces and/or are
designed to drop material from one conveyor to another (e.g., in a
step, cascade or as a series of steps or a stair). Along with
conveying materials conveyors can be used, by themselves or coupled
with other equipment or systems, for screening, separating,
sorting, classifying, distributing, sizing, inspection, picking,
metal removing, freezing, blending, mixing, orienting, heating,
cooking, drying, dewatering, cleaning, washing, leaching,
quenching, coating, de-dusting and/or feeding. The conveyors can
also include covers (e.g., dust-tight covers), side discharge
gates, bottom discharge gates, special liners (e.g., anti-stick,
stainless steel, rubber, custom steal, and or grooved), divided
troughs, quench pools, screens, perforated plates, detectors (e.g.,
metal detectors), high temperature designs, food grade designs,
heaters, dryers and or coolers. In addition, the trough can be of
various shapes, for example, flat bottomed, vee shaped bottom,
flanged at the top, curved bottom, flat with ridges in any
direction, tubular, half pipe, covered or any combinations of
these. In particular, the conveyors can be coupled with an
irradiation systems and/or equipment.
[0190] The conveyors (e.g., vibratory conveyor) can be made of
corrosion resistant materials. The conveyors can utilize structural
materials that include stainless steel (e.g., 304, 316 stainless
steel, HASTELLOY.RTM. ALLOYS and INCONEL.RTM. Alloys). For example,
HASTELLOY.RTM. Corrosion-Resistant alloys from Hynes (Kokomo, Ind.,
USA) such as HASTELLOY.RTM. B-3.RTM. ALLOY, HASTELLOY.RTM.
HYBRID-BC1.RTM. ALLOY, HASTELLOY.RTM. C-4 ALLOY, HASTELLOY.RTM.
C-22.RTM. ALLOY, HASTELLOY.RTM. C-22HS.RTM. ALLOY, HASTELLOY.RTM.
C-276 ALLOY, HASTELLOY.RTM. C-2000.RTM. ALLOY, HASTELLOY.RTM.
G-30.RTM. ALLOY, HASTELLOY.RTM. G-35.RTM. ALLOY, HASTELLOY.RTM. N
ALLOY and HASTELLOY.RTM. ULTIMET.RTM. alloy.
[0191] The vibratory conveyors can include non-stick release
coatings, for example, TUFFLON.TM. (Dupont, Del., USA). The
vibratory conveyors can also include corrosion resistant coatings.
For example, coatings that can be supplied from Metal Coatings Corp
(Houston, Tex., USA) and others such as Fluoropolymer, XYLAN.RTM.,
Molybdenum Disulfide, Epoxy Phenolic, Phosphate--ferrous metal
coating, Polyurethane--high gloss topcoat for epoxy, inorganic
zinc, Poly Tetrafluoro ethylene, PPS/RYTON.RTM., fluorinated
ethylene propylene, PVDF/DYKOR.RTM., ECTFE/HALAR.RTM. and Ceramic
Epoxy Coating. The coatings can improve resistance to process gases
(e.g., ozone), chemical corrosion, pitting corrosion, galling
corrosion and oxidation.
[0192] Optionally, in addition to the conveying systems described
herein, one or more other conveying systems can be enclosed. When
using an enclosure, the enclosed conveyor can also be purged with
an inert gas so as to maintain an atmosphere at a reduced oxygen
level. Keeping oxygen levels low avoids the formation of ozone
which in some instances is undesirable due to its reactive and
toxic nature. For example, the oxygen can be less than about 20%
(e.g., less than about 10%, less than about 1%, less than about
0.1%, less than about 0.01%, or even less than about 0.001%
oxygen). Purging can be done with an inert gas including, but not
limited to, nitrogen, argon, helium or carbon dioxide. This can be
supplied, for example, from a boil off of a liquid source (e.g.,
liquid nitrogen or helium), generated or separated from air in
situ, or supplied from tanks. The inert gas can be recirculated and
any residual oxygen can be removed using a catalyst, such as a
copper catalyst bed. Alternatively, combinations of purging,
recirculating and oxygen removal can be done to keep the oxygen
levels low.
[0193] The enclosed conveyor can also be purged with a reactive gas
that can react with the biomass. This can be done before, during or
after the irradiation process. The reactive gas can be, but is not
limited to, nitrous oxide, ammonia, oxygen, ozone, hydrocarbons,
aromatic compounds, amides, peroxides, azides, halides, oxyhalides,
phosphides, phosphines, arsines, sulfides, thiols, boranes and/or
hydrides. The reactive gas can be activated in the enclosure, e.g.,
by irradiation (e.g., electron beam, UV irradiation, microwave
irradiation, heating, IR radiation), so that it reacts with the
biomass. The biomass itself can be activated, for example by
irradiation. Preferably the biomass is activated by the electron
beam, to produce radicals which then react with the activated or
unactivated reactive gas, e.g., by radical coupling or
quenching.
[0194] Purging gases supplied to an enclosed conveyor can also be
cooled, for example below about 25.degree. C., below about
0.degree. C., below about -40.degree. C., below about -80.degree.
C., below about -120.degree. C. For example, the gas can be boiled
off from a compressed gas such as liquid nitrogen or sublimed from
solid carbon dioxide. As an alternative example, the gas can be
cooled by a chiller or part of or the entire conveyor can be
cooled.
Other Embodiments
[0195] Any material, processes or processed materials discussed
herein can be used to make products and/or intermediates such as
composites, fillers, binders, plastic additives, adsorbents and
controlled release agents. The methods can include densification,
for example, by applying pressure and heat to the materials. For
example composites can be made by combining fibrous materials with
a resin or polymer. For example radiation cross-linkable resin,
e.g., a thermoplastic resin can be combined with a fibrous material
to provide a fibrous material/cross-linkable resin combination.
Such materials can be, for example, useful as building materials,
protective sheets, containers and other structural materials (e.g.,
molded and/or extruded products). Absorbents can be, for example,
in the form of pellets, chips, fibers and/or sheets. Adsorbents can
be used, for example, as pet bedding, packaging material or in
pollution control systems. Controlled release matrices can also be
the form of, for example, pellets, chips, fibers and or sheets. The
controlled release matrices can, for example, be used to release
drugs, biocides, fragrances. For example, composites, absorbents
and control release agents and their uses are described in
International Serial No. PCT/US2006/010648, filed Mar. 23, 2006,
and U.S. Pat. No. 8,074,910 filed Nov. 22, 2011, the entire
disclosures of which are herein incorporated by reference.
[0196] In some instances the biomass material is treated at a first
level to reduce recalcitrance, e.g., utilizing accelerated
electrons, to selectively release one or more sugars (e.g.,
xylose). The biomass can then be treated to a second level to
release one or more other sugars (e.g., glucose). Optionally the
biomass can be dried between treatments. The treatments can include
applying chemical and biochemical treatments to release the sugars.
For example, a biomass material can be treated to a level of less
than about 20 Mrad (e.g., less than about 15 Mrad, less than about
10 Mrad, less than about 5 Mrad, less than about 2 Mrad) and then
treated with a solution of sulfuric acid, containing less than 10%
sulfuric acid (e.g., less than about 9%, less than about 8%, less
than about 7%, less than about 6%, less than about 5%, less than
about 4%, less than about 3%, less than about 2%, less than about
1%, less than about 0.75%, less than about 0.50%, less than about
0.25%) to release xylose. Xylose, for example that is released into
solution, can be separated from solids and optionally the solids
washed with a solvent/solution (e.g., with water and/or acidified
water). Optionally, the solids can be dried, for example in air
and/or under vacuum optionally with heating (e.g., below about 150
deg C., below about 120 deg C.) to a water content below about 25
wt. % (below about 20 wt. %, below about 15 wt. %, below about 10
wt. %, below about 5 wt. %). The solids can then be treated with a
level of less than about 30 Mrad (e.g., less than about 25 Mrad,
less than about 20 Mrad, less than about 15 Mrad, less than about
10 Mrad, less than about 5 Mrad, less than about 1 Mrad or even not
at all) and then treated with an enzyme (e.g., a cellulase) to
release glucose. The glucose (e.g., glucose in solution) can be
separated from the remaining solids. The solids can then be further
processed, for example utilized to make energy or other products
(e.g., lignin derived products).
Flavors, Fragrances and Colorants
[0197] Any of the products and/or intermediates described herein,
for example, produced by the processes, systems and/or equipment
described herein, can be combined with flavors, fragrances,
colorants and/or mixtures of these. For example, any one or more of
(optionally along with flavors, fragrances and/or colorants)
sugars, organic acids, fuels, polyols, such as sugar alcohols,
biomass, fibers and composites can be combined with (e.g.,
formulated, mixed or reacted) or used to make other products. For
example, one or more such product can be used to make soaps,
detergents, candies, drinks (e.g., cola, wine, beer, liquors such
as gin or vodka, sports drinks, coffees, teas), syrups,
pharmaceuticals, adhesives, sheets (e.g., woven, none woven,
filters, tissues) and/or composites (e.g., boards). For example,
one or more such product can be combined with herbs, flowers,
petals, spices, vitamins, potpourri, or candles. For example, the
formulated, mixed or reacted combinations can have
flavors/fragrances of grapefruit, orange, apple, raspberry, banana,
lettuce, celery, cinnamon, chocolate, vanilla, peppermint, mint,
onion, garlic, pepper, saffron, ginger, milk, wine, beer, tea, lean
beef, fish, clams, olive oil, coconut fat, pork fat, butter fat,
beef bouillon, legume, potatoes, marmalade, ham, coffee and
cheeses.
[0198] Flavors, fragrances and colorants can be added in any
amount, such as between about 0.001 wt. % to about 30 wt. %, e.g.,
between about 0.01 to about 20, between about 0.05 to about 10, or
between about 0.1 wt. % to about 5 wt. %. These can be formulated,
mixed and or reacted (e.g., with any one of more product or
intermediate described herein) by any means and in any order or
sequence (e.g., agitated, mixed, emulsified, gelled, infused,
heated, sonicated, and/or suspended). Fillers, binders, emulsifier,
antioxidants can also be utilized, for example protein gels,
starches and silica.
[0199] In one embodiment the flavors, fragrances and colorants can
be added to the biomass immediately after the biomass is irradiated
such that the reactive sites created by the irradiation may react
with reactive compatible sites of the flavors, fragrances, and
colorants.
[0200] The flavors, fragrances and colorants can be natural and/or
synthetic materials. These materials can be one or more of a
compound, a composition or mixtures of these (e.g., a formulated or
natural composition of several compounds). Optionally the flavors,
fragrances, antioxidants and colorants can be derived biologically,
for example, from a fermentation process (e.g., fermentation of
saccharified materials as described herein). Alternatively, or
additionally these flavors, fragrances and colorants can be
harvested from a whole organism (e.g., plant, fungus, animal,
bacteria or yeast) or a part of an organism. The organism can be
collected and or extracted to provide color, flavors, fragrances
and/or antioxidant by any means including utilizing the methods,
systems and equipment described herein, hot water extraction,
supercritical fluid extraction, chemical extraction (e.g., solvent
or reactive extraction including acids and bases), mechanical
extraction (e.g., pressing, comminuting, filtering), utilizing an
enzyme, utilizing a bacteria such as to break down a starting
material, and combinations of these methods. The compounds can be
derived by a chemical reaction, for example, the combination of a
sugar (e.g., as produced as described herein) with an amino acid
(Maillard reaction). The flavor, fragrance, antioxidant and/or
colorant can be an intermediate and or product produced by the
methods, equipment or systems described herein, for example and
ester and a lignin derived product.
[0201] Some examples of flavor, fragrances or colorants are
polyphenols. Polyphenols are pigments responsible for the red,
purple and blue colorants of many fruits, vegetables, cereal
grains, and flowers. Polyphenols also can have antioxidant
properties and often have a bitter taste. The antioxidant
properties make these important preservatives. On class of
polyphenols are the flavonoids, such as Anthocyanidines,
flavanonols, flavan-3-ols, s, flavanones and flavanonols. Other
phenolic compounds that can be used include phenolic acids and
their esters, such as chlorogenic acid and polymeric tannins.
[0202] Among the colorants inorganic compounds, minerals or organic
compounds can be used, for example titanium dioxide, zinc oxide,
aluminum oxide, cadmium yellow (E.g., CdS), cadmium orange (e.g.,
CdS with some Se), alizarin crimson (e.g., synthetic or
non-synthetic rose madder), ultramarine (e.g., synthetic
ultramarine, natural ultramarine, synthetic ultramarine violet),
cobalt blue, cobalt yellow, cobalt green, viridian (e.g., hydrated
chromium(III)oxide), chalcophylite, conichalcite, cornubite,
cornwallite and liroconite. Black pigments such as carbon black and
self-dispersed blacks may be used.
[0203] Some flavors and fragrances that can be utilized include
ACALEA TBHQ, ACET C-6, ALLYL AMYL GLYCOLATE, ALPHA TERPINEOL,
AMBRETTOLIDE, AMBRINOL 95, ANDRANE, APHERMATE, APPLELIDE,
BACDANOL.RTM., BERGAMAL, BETA IONONE EPOXIDE, BETA NAPHTHYL
ISO-BUTYL ETHER, BICYCLONONALACTONE, BORNAFIX.RTM., CANTHOXAL,
CASHMERAN.RTM., CASHMERAN.RTM. VELVET, CASSIFFIX.RTM., CEDRAFIX,
CEDRAMBER.RTM., CEDRYL ACETATE, CELESTOLIDE, CINNAMALVA, CITRAL
DIMETHYL ACETATE, CITROLATE.TM., CITRONELLOL 700, CITRONELLOL 950,
CITRONELLOL COEUR, CITRONELLYL ACETATE, CITRONELLYL ACETATE PURE,
CITRONELLYL FORMATE, CLARYCET, CLONAL, CONIFERAN, CONIFERAN PURE,
CORTEX ALDEHYDE 50% PEOMOSA, CYCLABUTE, CYCLACET.RTM.,
CYCLAPROP.RTM., CYCLEMAX.TM., CYCLOHEXYL ETHYL ACETATE, DAMASCOL,
DELTA DAMASCONE, DIHYDRO CYCLACET, DIHYDRO MYRCENOL, DIHYDRO
TERPINEOL, DIHYDRO TERPINYL ACETATE, DIMETHYL CYCLORMOL, DIMETHYL
OCTANOL PQ, DIMYRCETOL, DIOLA, DIPENTENE, DULCINYL.RTM.
RECRYSTALLIZED, ETHYL-3-PHENYL GLYCIDATE, FLEURAMONE, FLEURANIL,
FLORAL SUPER, FLORALOZONE, FLORIFFOL, FRAISTONE, FRUCTONE,
GALAXOLIDE.RTM. 50, GALAXOLIDE.RTM. 50 BB, GALAXOLIDE.RTM. 50 IPM,
GALAXOLIDE.RTM. UNDILUTED, GALBASCONE, GERALDEHYDE, GERANIOL 5020,
GERANIOL 600 TYPE, GERANIOL 950, GERANIOL 980 (PURE), GERANIOL CFT
COEUR, GERANIOL COEUR, GERANYL ACETATE COEUR, GERANYL ACETATE,
PURE, GERANYL FORMATE, GRISALVA, GUAIYL ACETATE, HELIONAL.TM.,
HERBAC, HERBALIME.TM., HEXADECANOLIDE, HEXALON, HEXENYL SALICYLATE
CIS 3-, HYACINTH BODY, HYACINTH BODY NO. 3, HYDRATROPIC
ALDEHYDE.DMA, HYDROXYOL, INDOLAROME, INTRELEVEN ALDEHYDE,
INTRELEVEN ALDEHYDE SPECIAL, IONONE ALPHA, IONONE BETA, ISO CYCLO
CITRAL, ISO CYCLO GERANIOL, ISO E SUPER.RTM., ISOBUTYL QUINOLINE,
JASMAL, JESSEMAL.RTM., KHARISMAL.RTM., KHARISMAL.RTM. SUPER,
KHUSINIL, KOAVONE.RTM., KOHINOOL.RTM., LIFFAROME.TM., LIMOXAL,
LINDENOL.TM., LYRAL.RTM., LYRAME SUPER, MANDARIN ALD 10% TRI ETH,
CITR, MARITIMA, MCK CHINESE, MEIJIFF.TM., MELAFLEUR, MELOZONE,
METHYL ANTHRANILATE, METHYL IONONE ALPHA EXTRA, METHYL IONONE GAMMA
A, METHYL IONONE GAMMA COEUR, METHYL IONONE GAMMA PURE, METHYL
LAVENDER KETONE, MONTAVERDI.RTM., MUGUESIA, MUGUET ALDEHYDE 50,
MUSK Z4, MYRAC ALDEHYDE, MYRCENYL ACETATE, NECTARATE.TM., NEROL
900, NERYL ACETATE, OCIMENE, OCTACETAL, ORANGE FLOWER ETHER,
ORIVONE, ORRINIFF 25%, OXASPIRANE, OZOFLEUR, PAMPLEFLEUR.RTM.,
PEOMOSA, PHENOXANOL.RTM., PICONIA, PRECYCLEMONE B, PRENYL ACETATE,
PRISMANTOL, RESEDA BODY, ROSALVA, ROSAMUSK, SANJINOL,
SANTALIFF.TM., SYVERTAL, TERPINEOL, TERPINOLENE 20, TERPINOLENE 90
PQ, TERPINOLENE RECT., TERPINYL ACETATE, TERPINYL ACETATE JAX,
TETRAHYDRO, MUGUOL.RTM., TETRAHYDRO MYRCENOL, TETRAMERAN,
TIMBERSILK.TM., TOBACAROL, TRIMOFIX.RTM. O TT, TRIPLAL.RTM.,
TRISAMBER.RTM., VANORIS, VERDOX.TM., VERDOX.TM. HC, VERTENEX.RTM.,
VERTENEX.RTM. HC, VERTOFIX.RTM. COEUR, VERTOLIFF, VERTOLIFF ISO,
VIOLIFF, VIVALDIE, ZENOLIDE, ABS INDIA 75 PCT MIGLYOL, ABS MOROCCO
50 PCT DPG, ABS MOROCCO 50 PCT TEC, ABSOLUTE FRENCH, ABSOLUTE
INDIA, ABSOLUTE MD 50 PCT BB, ABSOLUTE MOROCCO, CONCENTRATE PG,
TINCTURE 20 PCT, AMBERGRIS, AMBRETTE ABSOLUTE, AMBRETTE SEED OIL,
ARMOISE OIL 70 PCT THUYONE, BASIL ABSOLUTE GRAND VERT, BASIL GRAND
VERT ABS MD, BASIL OIL GRAND VERT, BASIL OIL VERVEINA, BASIL OIL
VIETNAM, BAY OIL TERPENELESS, BEESWAX ABS N G, BEESWAX ABSOLUTE,
BENZOIN RESINOID SIAM, BENZOIN RESINOID SIAM 50 PCT DPG, BENZOIN
RESINOID SIAM 50 PCT PG, BENZOIN RESINOID SIAM 70.5 PCT TEC,
BLACKCURRANT BUD ABS 65 PCT PG, BLACKCURRANT BUD ABS MD 37 PCT TEC,
BLACKCURRANT BUD ABS MIGLYOL, BLACKCURRANT BUD ABSOLUTE BURGUNDY,
BOIS DE ROSE OIL, BRAN ABSOLUTE, BRAN RESINOID, BROOM ABSOLUTE
ITALY, CARDAMOM GUATEMALA CO2 EXTRACT, CARDAMOM OIL GUATEMALA,
CARDAMOM OIL INDIA, CARROT HEART, CASSIE ABSOLUTE EGYPT, CASSIE
ABSOLUTE MD 50 PCT IPM, CASTOREUM ABS 90 PCT TEC, CASTOREUM ABS C
50 PCT MIGLYOL, CASTOREUM ABSOLUTE, CASTOREUM RESINOID, CASTOREUM
RESINOID 50 PCT DPG, CEDROL CEDRENE, CEDRUS ATLANTICA OIL REDIST,
CHAMOMILE OIL ROMAN, CHAMOMILE OIL WILD, CHAMOMILE OIL WILD LOW
LIMONENE, CINNAMON BARK OIL CEYLAN, CISTE ABSOLUTE, CISTE ABSOLUTE
COLORLESS, CITRONELLA OIL ASIA IRON FREE, CIVET ABS 75 PCT PG,
CIVET ABSOLUTE, CIVET TINCTURE 10 PCT, CLARY SAGE ABS FRENCH DECOL,
CLARY SAGE ABSOLUTE FRENCH, CLARY SAGE C'LESS 50 PCT PG, CLARY SAGE
OIL FRENCH, COPAIBA BALSAM, COPAIBA BALSAM OIL, CORIANDER SEED OIL,
CYPRESS OIL, CYPRESS OIL ORGANIC, DAVANA OIL, GALBANOL, GALBANUM
ABSOLUTE COLORLESS, GALBANUM OIL, GALBANUM RESINOID, GALBANUM
RESINOID 50 PCT DPG, GALBANUM RESINOID HERCOLYN BHT, GALBANUM
RESINOID TEC BHT, GENTIANE ABSOLUTE MD 20 PCT BB, GENTIANE
CONCRETE, GERANIUM ABS EGYPT MD, GERANIUM ABSOLUTE EGYPT, GERANIUM
OIL CHINA, GERANIUM OIL EGYPT, GINGER OIL 624, GINGER OIL RECTIFIED
SOLUBLE, GUAIACWOOD HEART, HAY ABS MD 50 PCT BB, HAY ABSOLUTE, HAY
ABSOLUTE MD 50 PCT TEC, HEALINGWOOD, HYSSOP OIL ORGANIC, IMMORTELLE
ABS YUGO MD 50 PCT TEC, IMMORTELLE ABSOLUTE SPAIN, IMMORTELLE
ABSOLUTE YUGO, JASMIN ABS INDIA MD, JASMIN ABSOLUTE EGYPT, JASMIN
ABSOLUTE INDIA, ASMIN ABSOLUTE MOROCCO, JASMIN ABSOLUTE SAMBAC,
JONQUILLE ABS MD 20 PCT BB, JONQUILLE ABSOLUTE France, JUNIPER
BERRY OIL FLG, JUNIPER BERRY OIL RECTIFIED SOLUBLE, LABDANUM
RESINOID 50 PCT TEC, LABDANUM RESINOID BB, LABDANUM RESINOID MD,
LABDANUM RESINOID MD 50 PCT BB, LAVANDIN ABSOLUTE H, LAVANDIN
ABSOLUTE MD, LAVANDIN OIL ABRIAL ORGANIC, LAVANDIN OIL GROSSO
ORGANIC, LAVANDIN OIL SUPER, LAVENDER ABSOLUTE H, LAVENDER ABSOLUTE
MD, LAVENDER OIL COUMARIN FREE, LAVENDER OIL COUMARIN FREE ORGANIC,
LAVENDER OIL MAILLETTE ORGANIC, LAVENDER OIL MT, MACE ABSOLUTE BB,
MAGNOLIA FLOWER OIL LOW METHYL EUGENOL, MAGNOLIA FLOWER OIL,
MAGNOLIA FLOWER OIL MD, MAGNOLIA LEAF OIL, MANDARIN OIL MD,
MANDARIN OIL MD BHT, MATE ABSOLUTE BB, MOSS TREE ABSOLUTE MD TEX
IFRA 43, MOSS-OAK ABS MD TEC IFRA 43, MOSS-OAK ABSOLUTE IFRA 43,
MOSS-TREE ABSOLUTE MD IPM IFRA 43, MYRRH RESINOID BB, MYRRH
RESINOID MD, MYRRH RESINOID TEC, MYRTLE OIL IRON FREE, MYRTLE OIL
TUNISIA RECTIFIED, NARCISSE ABS MD 20 PCT BB, NARCISSE ABSOLUTE
FRENCH, NEROLI OIL TUNISIA, NUTMEG OIL TERPENELESS, OEILLET
ABSOLUTE, OLIBANUM RESINOID, OLIBANUM RESINOID BB, OLIBANUM
RESINOID DPG, OLIBANUM RESINOID EXTRA 50 PCT DPG, OLIBANUM RESINOID
MD, OLIBANUM RESINOID MD 50 PCT DPG, OLIBANUM RESINOID TEC,
OPOPONAX RESINOID TEC, ORANGE BIGARADE OIL MD BHT, ORANGE BIGARADE
OIL MD SCFC, ORANGE FLOWER ABSOLUTE TUNISIA, ORANGE FLOWER WATER
ABSOLUTE TUNISIA, ORANGE LEAF ABSOLUTE, ORANGE LEAF WATER ABSOLUTE
TUNISIA, ORRIS ABSOLUTE ITALY, ORRIS CONCRETE 15 PCT IRONE, ORRIS
CONCRETE 8 PCT IRONE, ORRIS NATURAL 15 PCT IRONE 4095C, ORRIS
NATURAL 8 PCT IRONE 2942C, ORRIS RESINOID, OSMANTHUS ABSOLUTE,
OSMANTHUS ABSOLUTE MD 50 PCT BB, PATCHOULI HEART N.sup.o3,
PATCHOULI OIL INDONESIA, PATCHOULI OIL INDONESIA IRON FREE,
PATCHOULI OIL INDONESIA MD, PATCHOULI OIL REDIST, PENNYROYAL HEART,
PEPPERMINT ABSOLUTE MD, PETITGRAIN BIGARADE OIL TUNISIA, PETITGRAIN
CITRONNIER OIL, PETITGRAIN OIL PARAGUAY TERPENELESS, PETITGRAIN OIL
TERPENELESS STAB, PIMENTO BERRY OIL, PIMENTO LEAF OIL, RHODINOL EX
GERANIUM CHINA, ROSE ABS BULGARIAN LOW METHYL EUGENOL, ROSE ABS
MOROCCO LOW METHYL EUGENOL, ROSE ABS TURKISH LOW METHYL EUGENOL,
ROSE ABSOLUTE, ROSE ABSOLUTE BULGARIAN, ROSE ABSOLUTE DAMASCENA,
ROSE ABSOLUTE MD, ROSE ABSOLUTE MOROCCO, ROSE ABSOLUTE TURKISH,
ROSE OIL BULGARIAN, ROSE OIL DAMASCENA LOW METHYL EUGENOL, ROSE OIL
TURKISH, ROSEMARY OIL CAMPHOR ORGANIC, ROSEMARY OIL TUNISIA,
SANDALWOOD OIL INDIA, SANDALWOOD OIL INDIA RECTIFIED, SANTALOL,
SCHINUS MOLLE OIL, ST JOHN BREAD TINCTURE 10 PCT, STYRAX RESINOID,
STYRAX RESINOID, TAGETE OIL, TEA TREE HEART, TONKA BEAN ABS 50 PCT
SOLVENTS, TONKA BEAN ABSOLUTE, TUBEROSE ABSOLUTE INDIA, VETIVER
HEART EXTRA, VETIVER OIL HAITI, VETIVER OIL HAITI MD, VETIVER OIL
JAVA, VETIVER OIL JAVA MD, VIOLET LEAF ABSOLUTE EGYPT, VIOLET LEAF
ABSOLUTE EGYPT DECOL, VIOLET LEAF ABSOLUTE FRENCH, VIOLET LEAF
ABSOLUTE MD 50 PCT BB, WORMWOOD OIL TERPENELESS, YLANG EXTRA OIL,
YLANG III OIL and combinations of these.
[0204] The colorants can be among those listed in the Color Index
International by the Society of Dyers and Colourists. Colorants
include dyes and pigments and include those commonly used for
coloring textiles, paints, inks and inkjet inks. Some colorants
that can be utilized include carotenoids, arylide yellows,
diarylide yellows, .beta.-naphthols, naphthols, benzimidazolones,
disazo condensation pigments, pyrazolones, nickel azo yellow,
phthalocyanines, quinacridones, perylenes and perinones,
isoindolinone and isoindoline pigments, triarylcarbonium pigments,
diketopyrrolo-pyrrole pigments, thioindigoids. Cartenoids include,
e.g., alpha-carotene, beta-carotene, gamma-carotene, lycopene,
lutein and astaxanthin Annatto extract, Dehydrated beets (beet
powder), Canthaxanthin, Caramel, .beta.-Apo-8'-carotenal, Cochineal
extract, Carmine, Sodium copper chlorophyllin, Toasted partially
defatted cooked cottonseed flour, Ferrous gluconate, Ferrous
lactate, Grape color extract, Grape skin extract (enocianina),
Carrot oil, Paprika, Paprika oleoresin, Mica-based pearlescent
pigments, Riboflavin, Saffron, Titanium dioxide, Tomato lycopene
extract; tomato lycopene concentrate, Turmeric, Turmeric oleoresin,
FD&C Blue No. 1, FD&C Blue No. 2, FD&C Green No. 3,
Orange B, Citrus Red No. 2, FD&C Red No. 3, FD&C Red No.
40, FD&C Yellow No. 5, FD&C Yellow No. 6, Alumina (dried
aluminum hydroxide), Calcium carbonate, Potassium sodium copper
chlorophyllin (chlorophyllin-copper complex), Dihydroxyacetone,
Bismuth oxychloride, Ferric ammonium ferrocyanide, Ferric
ferrocyanide, Chromium hydroxide green, Chromium oxide greens,
Guanine, Pyrophyllite, Talc, Aluminum powder, Bronze powder, Copper
powder, Zinc oxide, D&C Blue No. 4, D&C Green No. 5,
D&C Green No. 6, D&C Green No. 8, D&C Orange No. 4,
D&C Orange No. 5, D&C Orange No. 10, D&C Orange No. 11,
FD&C Red No. 4, D&C Red No. 6, D&C Red No. 7, D&C
Red No. 17, D&C Red No. 21, D&C Red No. 22, D&C Red No.
27, D&C Red No. 28, D&C Red No. 30, D&C Red No. 31,
D&C Red No. 33, D&C Red No. 34, D&C Red No. 36, D&C
Red No. 39, D&C Violet No. 2, D&C Yellow No. 7, Ext.
D&C Yellow No. 7, D&C Yellow No. 8, D&C Yellow No. 10,
D&C Yellow No. 11, D&C Black No. 2, D&C Black No. 3
(3), D&C Brown No. 1, Ext. D&C, Chromium-cobalt-aluminum
oxide, Ferric ammonium citrate, Pyrogallol, Logwood extract,
1,4-Bis[(2-hydroxy-ethyl)amino]-9,10-anthracenedione
bis(2-propenoic)ester copolymers,
1,4-Bis[(2-methylphenyl)amino]-9,10-anthracenedione,
1,4-Bis[4-(2-methacryloxyethyl)phenylamino]anthraquinone
copolymers, Carbazole violet, Chlorophyllin-copper complex,
Chromium-cobalt-aluminum oxide, C.I. Vat Orange 1,
2-[[2,5-Diethoxy-4-[(4-methylphenyl)thiol]phenyl]azo]-1,3,5-benzenetriol,
16,23-Dihydrodinaphtho[2,3-a:2',3'-i]naphth[2',3':6,7]indolo[2,3-c]carbaz-
ole-5,10,15,17,22,24-hexone,
N,N'-(9,10-Dihydro-9,10-dioxo-1,5-anthracenediyl)bisbenzamide,
7,16-Dichloro-6,15-dihydro-5,9,14,18-anthrazinetetrone,
16,17-Dimethoxydinaphtho (1,2,3-cd:3',2',1'-lm)
perylene-5,10-dione, Poly(hydroxyethyl methacrylate)-dye
copolymers(3), Reactive Black 5, Reactive Blue 21, Reactive Orange
78, Reactive Yellow 15, Reactive Blue No. 19, Reactive Blue No. 4,
C.I. Reactive Red 11, C.I. Reactive Yellow 86, C.I. Reactive Blue
163, C.I. Reactive Red 180,
4-[(2,4-dimethylphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-on-
e (solvent Yellow 18),
6-Ethoxy-2-(6-ethoxy-3-oxobenzo[b]thien-2(3H)-ylidene)benzo[b]thiophen-3(-
2H)-one, Phthalocyanine green, Vinyl alcohol/methyl
methacrylate-dye reaction products, C.I. Reactive Red 180, C.I.
Reactive Black 5, C.I. Reactive Orange 78, C.I. Reactive Yellow 15,
C.I. Reactive Blue 21, Disodium
1-amino-4-[[4-[(2-bromo-1-oxoallyl)amino]-2-sulphonatophenyl]ami-
no]-9,10-dihydro-9,10-dioxoanthracene-2-sulphonate (Reactive Blue
69), D&C Blue No. 9, [Phthalocyaninato(2-)]copper and mixtures
of these.
[0205] Other than in the examples herein, or unless otherwise
expressly specified, all of the numerical ranges, amounts, values
and percentages, such as those for amounts of materials, elemental
contents, times and temperatures of reaction, ratios of amounts,
and others, in the following portion of the specification and
attached claims may be read as if prefaced by the word "about" even
though the term "about" may not expressly appear with the value,
amount, or range. Accordingly, unless indicated to the contrary,
the numerical parameters set forth in the following specification
and attached claims are approximations that may vary depending upon
the desired properties sought to be obtained by the present
invention. At the very least, and not as an attempt to limit the
application of the doctrine of equivalents to the scope of the
claims, each numerical parameter should at least be construed in
light of the number of reported significant digits and by applying
ordinary rounding techniques.
[0206] Notwithstanding that the numerical ranges and parameters
setting forth the broad scope of the invention are approximations,
the numerical values set forth in the specific examples are
reported as precisely as possible. Any numerical value, however,
inherently contains error necessarily resulting from the standard
deviation found in its underlying respective testing measurements.
Furthermore, when numerical ranges are set forth herein, these
ranges are inclusive of the recited range end points (e.g., end
points may be used). When percentages by weight are used herein,
the numerical values reported are relative to the total weight.
[0207] Also, it should be understood that any numerical range
recited herein is intended to include all sub-ranges subsumed
therein. For example, a range of "1 to 10" is intended to include
all sub-ranges between (and including) the recited minimum value of
1 and the recited maximum value of 10, that is, having a minimum
value equal to or greater than 1 and a maximum value of equal to or
less than 10. The terms "one," "a," or "an" as used herein are
intended to include "at least one" or "one or more," unless
otherwise indicated.
[0208] Any patent, publication, or other disclosure material, in
whole or in part, that is said to be incorporated by reference
herein is incorporated herein only to the extent that the
incorporated material does not conflict with existing definitions,
statements, or other disclosure material set forth in this
disclosure. As such, and to the extent necessary, the disclosure as
explicitly set forth herein supersedes any conflicting material
incorporated herein by reference. Any material, or portion thereof,
that is said to be incorporated by reference herein, but which
conflicts with existing definitions, statements, or other
disclosure material set forth herein will only be incorporated to
the extent that no conflict arises between that incorporated
material and the existing disclosure material.
[0209] While this invention has been particularly shown and
described with references to preferred embodiments thereof, it will
be understood by those skilled in the art that various changes in
form and details may be made therein without departing from the
scope of the invention encompassed by the appended claims.
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