U.S. patent application number 14/156704 was filed with the patent office on 2014-05-29 for prefabricated multi-modal bioenergy systems and methods.
This patent application is currently assigned to Impact Bioenergy, Inc.. The applicant listed for this patent is Impact Bioenergy, Inc.. Invention is credited to Jan Allen, Connor Folley, Thomas Kraemer.
Application Number | 20140147911 14/156704 |
Document ID | / |
Family ID | 44678047 |
Filed Date | 2014-05-29 |
United States Patent
Application |
20140147911 |
Kind Code |
A1 |
Allen; Jan ; et al. |
May 29, 2014 |
PREFABRICATED MULTI-MODAL BIOENERGY SYSTEMS AND METHODS
Abstract
A prefabricated, multi-modal, bio-mimicry system that can be
quickly deployed.
Inventors: |
Allen; Jan; (Shoreline,
WA) ; Folley; Connor; (Shoreline, WA) ;
Kraemer; Thomas; (Duvall, WA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Impact Bioenergy, Inc. |
Shoreline |
WA |
US |
|
|
Assignee: |
Impact Bioenergy, Inc.
Shoreline
WA
|
Family ID: |
44678047 |
Appl. No.: |
14/156704 |
Filed: |
January 16, 2014 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
13081053 |
Apr 6, 2011 |
8662791 |
|
|
14156704 |
|
|
|
|
61381304 |
Sep 9, 2010 |
|
|
|
Current U.S.
Class: |
435/267 ;
435/290.1 |
Current CPC
Class: |
C05F 17/979 20200101;
Y02W 30/47 20150501; Y10T 29/49826 20150115; Y02W 30/40 20150501;
Y02W 30/43 20150501; Y02E 50/343 20130101; C12M 43/02 20130101;
Y02P 20/145 20151101; Y02E 50/30 20130101; C05F 17/50 20200101;
C05F 17/986 20200101 |
Class at
Publication: |
435/267 ;
435/290.1 |
International
Class: |
C12M 1/00 20060101
C12M001/00 |
Claims
1. A prefabricated, multi-modal, bio-mimicry system in which at
least two modes are chosen from the group consisting of: an
alternating digester system, an above grade anaerobic digestion
system, an enclosed ventilated composting system, a wood
gasification system, a product-package separation system, a
trans-esterification system, a drying/pelleting/prilling
system.
2. The prefabricated, multi-modal, bio-mimicry system of claim 1
where at least one mode is an alternating digester system, if the
input is seasonal food or landscape waste.
3. The prefabricated, multi-modal, bio-mimicry system of claim 2
where the alternating digester system is a subterranean alternating
digester system.
4. The prefabricated, multi-modal, bio-mimicry system of claim 3
where the subterranean alternating digester system is comprised of:
a subterranean enclosure configured to hold organic matter, the
enclosure having a plurality of conduits in a bottom surface of the
enclosure; an irrigation system configured to dispense a liquid
from a top portion of the enclosure and to recover a percolated
liquid from a bottom portion of the enclosure; a ventilation system
configured to provide air flow to the bottom portion of the
enclosure; a leak detection zone below the bottom surface of the
enclosure configured to collect and recover fluid, wherein the
fluid includes groundwater that leaks upward, digester liquid that
leaks downward from the enclosure, or a combination thereof; and a
gas-tight membrane cover configured to cover the enclosure and to
store gas produced during digestion.
5. The prefabricated, multi-modal, bio-mimicry system of claim 1
where at least one mode is an above ground anaerobic digestion
system, if the input is food and/or soiled paper waste.
6. The prefabricated, multi-modal, bio-mimicry system of claim 1
where at least one mode is an enclosed ventilated composting
system, if the input is seasonal landscape waste, biosolids,
manure, and/or bedding.
7. The prefabricated, multi-modal, bio-mimicry system of claim 1
where at least one mode is a wood gasification system, if the input
is green and/or dry wood waste.
8. The prefabricated, multi-modal, bio-mimicry system of claim 1
where at least one mode is a product-package separation system, if
the input is packaged, unsaleable food.
9. The prefabricated, multi-modal, bio-mimicry system of claim 1
where at least one mode is a drying/pelleting/prilling system, if
the input is digestate, compost, and/or biochar.
10. The prefabricated, multi-modal, bio-mimicry system of claim 1
where at least one mode is a trans-esterification system, if the
input is fat, oil, and/or grease waste.
11. The prefabricated, multi-modal, bio-mimicry system of claim 1
where odor is controlled in a four-stage, series system of
enclosures: biofilter, carbon filter, and counteractant misting
system in an exhaust stack.
12. The prefabricated, multi-modal, bio-mimicry system of claim 1
where the prefabricated, multi-modal, bio-mimicry system is built
onto modular skids.
13. A method to scale a prefabricated, multi-modal, bio-mimicry
system in which at least two modes are chosen from the group
consisting of: an alternating digester system, an above grade
anaerobic digestion system, an enclosed ventilated composting
system, a wood gasification system, a product-package separation
system, a trans-esterification system, a drying/pelleting/prilling
system to process between 0.1 and 75 tons of input per day.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Non-provisional
application Ser. No. 13/081,053, filed Apr. 6, 2011, which claims
priority to U.S. Provisional Application No. 61/381,304, filed on
Sep. 10, 2010, the disclosure of which are is incorporated by
reference herein in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT
DISC
[0003] Not Applicable
BACKGROUND
[0004] Currently, anaerobic digestion, composting, gasification,
product-packaging separation, trans-esterification, drying,
pelleting, and prilling are used as independent processes. Each
process requires feedstock as input and is designed to produce a
single marketable product as output. Additionally, each of these
processes produces by-products that may become an operating expense
for disposal or an environmental liability; examples of these
by-products are digestate (digestion yields), woody oversized
particles (composting yield), ash (gasification yields), and
glycerin (trans-esterification yields). Generally, energy output is
also considered a by-product. For example, heat production from
composting and gasification are by-products. Commonly, design and
deployment of facilities that employ anaerobic digestion,
composting, gasification, product-packaging separation,
trans-esterification, drying, pelleting, or prilling processes
requires between 2 and 4 years. They are also typically designed as
large, centralized facilities due to the presumption that larger
facilities are more cost-efficient due to the larger economy of
scale. This presumption has proven to be incorrect in most urban
situations due to the high cost of hauling and transportation of
feedstocks (as inputs) and by-products (as outputs) over
increasingly longer distances.
[0005] Organic waste processing facilities are typically designed
at a scale of 100 to over 1,000 tons per day. They exist in four
industrial sectors: wastewater treatment, manure treatment,
industrial plants, and urban organic recycling plants. These
processing facilities control feedstock preparation, residence
time, temperature, moisture, density, oxygen, pH, and final
particle size. They may also control odors with a one-stage
treatment system.
[0006] There is a need for renewable energy, energy independence,
distributed energy generation, diversion of organic waste from
disposal and zero waste systems. ("Zero Waste Movement") Coupling
two or more of the above technologies together in a synergistic way
to reduce by-product waste and increase usable energy/heat
production will help achieve the goals of the Zero Waste Movement.
The practice of coupling these technologies can be referred to as
by-product synergy or bio-mimicry.
BRIEF DESCRIPTION OF INVENTION
[0007] An objective of this invention is to provide a multi-modal,
bio-mimicry system. Another objective is to provide a prefabricated
system that can be quickly deployed for use.
DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0008] Other features and advantages of the present invention will
become apparent in the following detailed descriptions of the
preferred embodiment with reference to the accompanying drawings,
of which:
[0009] FIG. 1 shows a plan view of a subterranean alternating
digester system according to embodiments of the present
invention;
[0010] FIG. 2 shows a cross-sectional view of a subterranean
alternating digester system according to embodiments of the present
invention;
[0011] FIG. 3 shows a process of alternating subterranean digesting
according to embodiments of the present invention;
[0012] FIG. 4 shows a cross-sectional view of a bottom surface of a
subterranean alternating digester system with conduits according to
embodiments of the present invention;
[0013] FIG. 5 shows a plan view of a covered conduit with channel
cover plates according to embodiments of the present invention;
[0014] FIG. 6 schematically shows an anaerobic phase in the
alternating subterranean digestion system according to illustrative
embodiments of the present invention;
[0015] FIG. 7 schematically shows an aerobic phase in the
alternating subterranean digestion system according to illustrative
embodiments of the present invention;
[0016] FIG. 8A schematically shows a side-view of a biofilter pipe
according to embodiments of the present invention;
[0017] FIG. 8B schematically shows a cross-sectional view of a
biofilter pipe along line A-A of FIG. 8A within biofilter
material;
[0018] FIG. 9 shows biofilter pipes placed on top of a biofilter
surface within a biofilter enclosure and surrounded by biofilter
media according to embodiments of the present invention;
[0019] FIG. 10 schematically shows an illustrative biofilter system
that may be used with embodiments of the present invention;
[0020] FIG. 11 shows a plan view of the digester enclosure with
pivoting screw conveyor and an excavator outside the enclosure
during pile restructuring or removal according to embodiments of
the present invention;
[0021] FIG. 12 shows a spike attached to a machine according to
embodiments of the present invention;
[0022] FIG. 13 shows a perspective view of a portion of the spike
with a sampling corbel according to embodiments of the present
invention;
[0023] FIG. 14 shows a side-view of the sampling corbel shown in
FIG. 13;
[0024] FIG. 15 schematically shows various locations of a machine
during pile restructuring or removal of the organic matter at the
end of the alternating subterranean digesting process according to
embodiments of the present invention;
[0025] FIG. 16 shows a system for processing seasonal food and
landscape waste;
[0026] FIG. 17 shows a system for processing food and soiled paper
waste;
[0027] FIG. 18 shows a system for processing seasonal landscape
waste;
[0028] FIG. 19 shows a system for processing biosolids, manure, and
bedding;
[0029] FIG. 20 shows a system for processing wood;
[0030] FIG. 21 shows a system for processing packaged and
unsaleable food;
[0031] FIG. 22 shows a system for processing fats, oils, and
grease; and
[0032] FIG. 23 shows a system for processing digestate, compost and
biochar.
DETAILED DESCRIPTION OF THE INVENTION
[0033] The present invention is related to a prefabricated,
multi-modal, bio-mimicry system. ("Bioenergy System") In the
Bioenergy System one of the above named processes, or their
equivalents, rely upon another process to avoid disposal expense
and/or environmental liability by utilizing by-product created in a
first mode in subsequent modes until by-products are no longer
usable or saleable. Multiple embodiments of the invention are
described hereinafter with reference to the accompanying drawings.
This invention may, however, be embodied in many different forms
and should not be construed as limited to the embodiments set forth
herein; rather, these embodiments are provided so that this
disclosure will be thorough and complete and will fully convey the
scope of the invention to those skilled in the art.
[0034] Although the Bioenergy System can be embodied in any number
of multi-modal combinations, each embodiment is a prefabricated
design that can be arranged quickly on the field. Mechanical
systems are prefabricated onto modular skids that can be
transported by truck or other means and positioned during
construction. Mechanical systems include but are not limited to
piping, valving, pumping, filtering, separating, and thermal
conditioning for solid and semi-solids, such as food waste, liquid
or gas circulation. Preferably, each skid is built to fit within a
space 8 feet wide by 40 feet long by 9 feet high and can be lifted
and installed in one movement with connections for power, controls,
inputs, and outputs minimized in number and located at the limits
of the skid. Preferably, the Bioenergy System is scaled to operate
between 0.1 to 75 tons per day allowing on-site processing and
eliminating the cost of hauling and transport.
[0035] Referring to FIG. 16, in one embodiment, seasonal food and
landscape wastes 200, from resorts, parks, island, and other
facilities having intermittent waste generation patterns, may be
processed in alternating digester system 210. In an alternating
digesting system 210, anaerobic digestion is followed by aerobic
digestion. Preferably, the alternating digester system 210 is
subterranean, as described below.
[0036] FIGS. 1 and 2 schematically show a plan view and a
cross-sectional view, respectively, of a subterranean alternating
digester system 10, and FIG. 3 shows a process of alternating
subterranean digesting according to its several embodiments.
Referring to 3, the process begins at step 100 in which a
subterranean enclosure 12 is provided. As shown in FIGS. 1 and 2,
the subterranean enclosure 12 is configured to hold organic matter
and may be constructed of steel sheeting or sheet piling, pre-cast
concrete panels with water tight joints, or cast-in-place concrete,
or other structural elements designed to withstand subterranean
earth pressure and contain the digesting material.
[0037] In step 110, the enclosure is covered with a flexible,
removable, gas-tight membrane 14. The membrane cover 14 has a
gas-tight seal that seals the membrane cover 14 to the perimeter of
the subterranean enclosure 12. The cover 14 prevents methane and
fugitive odor release and also helps to prevent evaporation loss.
As known by those skilled in the art, impermeable covers suitable
for use as geomembranes may include High-Density Polyethylene
(HDPE), Low-Density Polyethylene, Polypropylene, XR-5.RTM. (a woven
synthetic fabric of DuPont Dacron Polyester) and periplastid
reticulum (PPR) membranes and other flexible membrane
materials.
[0038] In step 120, a pile 16 of the organic matter is formed on a
bottom surface 12a of the subterranean enclosure 12. As shown in
FIG. 2, the bottom surface 12a has a series of conduits 18. Details
of the conduits 18 and their function will be discussed in more
detail below. Preferably, the organic matter includes larger,
oversized particles. During periods when larger particle materials
are unavailable, the feedstock may be amended with screening
oversized material, large woody particles cast off in the screening
process, bark, and similar forest product residuals. The removal of
the oversized particles may be accomplished at the final screening
process after the composting process is complete. The oversized
particles may include brush, branches, waxed or un-waxed corrugated
cardboard boxes, dimensional wood, pallets, and/or crating.
Preferably, the feedstock is a mixture of incoming organic matter,
screening oversized particles and woody materials. The feedstock
also, preferably, includes high-carbon amendments of at least about
95% carbon. The high-carbon amendments may include cedar bark,
wood, sawdust and/or paper.
[0039] Because oversized particles are used, initial grinding of
the feedstock is eliminated and brush, branches, dimensional wood,
broken pallets, paper bags with waste, plastic bags with waste, and
crating may be directly and immediately placed into the process
without particle size reduction allowing for more rapid feedstock
receiving and preparation. The use of oversized particles, along
with a pile restructuring apparatus, also eliminates the need for
pile turning during the digestion process. The pile restructuring
apparatus or spike is discussed in more detail below. As a result,
costs and emissions are significantly reduced. Because the
un-ground feedstock is lower in bulk density and higher in porosity
due to the inclusion of the larger particles, a deeper pile may be
used than is commonly used in composting practice. For example, the
pile of organic matter may be initially formed with an average
height of about 15-25 feet. Thus, embodiments of the present
invention provide more cost efficiency than other systems (e.g.,
approximately $30 per ton processed versus approximately $60 per
ton processed) and allow for more seasonal composition, volume, and
moisture variations through the use of a deeper pile and the
addition of the high-carbon amendments in the pile. For example,
the pile may have an initial density of no greater than about 700
pounds per cubic yard with a minimum porosity of about 50% by
volume. The pile may also have a density ranging from about 650 to
about 850 pounds per cubic yard over the entire residence time.
[0040] As shown in FIGS. 1 and 2, the organic matter may be fed
into the enclosed space created by the subterranean enclosure 12
and the gas-tight membrane 14 by means of a completely enclosed and
gas-tight screw conveyor 20. The conveyor 20 may have a pivot point
20a and multiple discharge chutes 20b. For example, FIG. 1 shows
the conveyor 20 in four different positions and FIG. 2 shows the
conveyor 20 with two discharge chutes, although multiple positions
and discharge chutes may be used. The conveyor 20 may be made
gas-tight by means of a resident plug of organic materials in the
enclosed screw and housing. The conveyor 20 may include a feed
hopper 22 and the screw in the conveyor 20 may determine the
maximum particle size of the organic material by means of a natural
shearing action and may open any bagged waste material. Although
the above discussion discloses that the enclosure 12 is covered
with the gas-tight membrane 14 before the pile 16 of organic matter
is formed in the enclosure, the pile may also be formed in the
enclosure first and then the enclosure 12 covered with the
gas-tight membrane 14. Similarly, the pile may be formed in the
enclosure first, then the enclosure 12 covered with the gas-tight
membrane 14, and then additional organic matter may be fed into the
enclosure 12. Thus, the feeding schedule of the conveyor 20 may be
continuous, intermittent, or even seasonal, and the digestion pile
may be built over time.
[0041] Referring again to FIG. 3, in step 130, a liquid percolation
system 24 irrigates the top of the pile with liquids. As shown in
FIG. 2, the irrigation system 24 may be coupled to the conveyor 20
or may be formed in a top portion of the enclosure 12 (not shown).
The liquid to be dispensed on the pile may contain nutrients,
buffering, and alkalinity to cultivate and maintain efficient
methanogenesis within the organic matter. During this anaerobic
phase of the process, liquids from the pile (e.g., produced from
the digestion process of the organic matter or from excess liquids
dispensed from the irrigation system) may be collected in the
conduits 18 at the bottom surface 12a of the enclosure 12.
[0042] The conduits 18 may be channels formed in the bottom surface
12a, such as shown in FIGS. 2 and 4, or may be pipes placed on the
bottom surface or in channels formed in the bottom surface (not
shown). The pipes have holes that allow fluid to flow from an area
outside of the pipe to within the pipe. When channels are used, the
series of conduits 18 may each have one or more channel cover
plates 26. As shown in greater detail in FIG. 5, each channel cover
plate 26 may include openings 26a that allow the percolate and
fluid from the pile 16 to flow into each conduit 18. The channel
cover plate 26 may be made of various materials, preferably
configured to withstand the forces of the pile and a machine, such
as an excavator, that may be placed on the bottom surface 12a of
the enclosure 12 when the digester batch is being removed. The
conduits 18 may be spaced any distance apart from one another,
e.g., about 8 feet apart, and may be formed of various materials,
e.g., constructed of cast in place concrete. For example, each
channel cover plate 26 may be about 48''.times.75'' and the
openings 26a may be about 1.5''.times.3'' with 3'' spacing and 6''
spacing between openings. Alternatively, a layer of porous material
designed to withstand the forces of the pile and a machine 64, such
as an excavator, that may be placed on the bottom surface 12a of
the enclosure 12 when the digester batch is being removed may be
used to convey the liquid at the bottom of the enclosure.
[0043] As shown in FIGS. 1 and 2, the conduits 18 collect the
percolate and fluid from the pile 16 and a submersible pump 28
pumps the liquid through a vertical manifold 30 to a liquid
digester 32 adjacent to the digester system 10. The irrigation
system 24 is in fluid communication with the liquid digester 32.
The vertical manifold 30 may be formed of various materials, e.g.,
concrete, steel, or HDPE pipe. The liquid stored in the liquid
digester 32 may consist of hydrolyzed liquids from the pile and
make up water. The liquid is provided to the pile 16 and is
collected through the conduits 18 such that a continuous production
of biomethane occurs. The liquid in the irrigation system 24 may be
maintained at a desired temperature to control the interior
temperature in the digester enclosure 12. For example, the liquid
may be heated in the liquid digester 32 or in the pipes in the
irrigation system 22. When the percolate recovery and return system
is operating and temperatures in the liquid and digester enclosure
12 are maintained in the optimum range, the production of
biomethane increases significantly.
[0044] The biomethane production rate is measured for methane
content and gross volumetric biogas production. Longer residence
time, higher temperatures, and efficient liquid to organic matter
contact (during percolation) are factors that increase actual
biomethane yield. An example of this embodiment would be 6 months
of residence time, a uniform 100.degree. F. digester temperature,
and an initial bulk density of 600-700 lbs per cubic yard. The
biogas produced may be recovered from the top portion of the
enclosure 12 and captured for later use.
[0045] As shown in FIGS. 2 and 4, the digester system 10 may also
include a lower surface 10a formed on the native soil 34 and
beneath the conduits 18. For example, the bottom surface 12a of the
enclosure 12 and lower surface 10a of the system 10 may be
constructed of concrete. The lower surface 10a of the system may be
installed underwater as a tremie concrete plug to exclude
groundwater and facilitate construction of the digester system 10
in areas of high groundwater. Between the bottom surface 12a and
the lower surface 10a, a coarse (porous) mineral aggregate layer or
other porous material 36 may be used between the surfaces, creating
a leak detection zone. The leak detection zone may include a
submersible pump 38 that pumps any recovered liquid to a liquid
storage tank 40 adjacent to the digester system 10, as shown in
FIG. 1. The recovered liquid may be groundwater that leaks upward
from below the lower surface 10a or digester liquid that leaks
downward from the digester enclosure 12, or a combination of both.
After characterizing the liquid, the liquid can be either reused or
disposed of depending upon its quality.
[0046] Referring again to FIG. 3, in step 140, the process then
alternates to an aerobic environment for subsequent aerobic
composting when the desired biomethane yield has been achieved.
This is accomplished by turning the liquid irrigation system 24 off
and removing all excess liquid from the system 10. Then, air is
forced into the digester enclosure 12 using one or more pressure
blowers or fans 42. The pressure fan 42 is configured to provide
air flow through the conduits 18 such that a positive air pressure
is formed at the bottom of the pile 16 forcing air through the pile
and causing heat and moisture to exhaust out of the top of the pile
16. FIGS. 6 and 7 schematically show the flow of liquids and air in
the anaerobic phase and the aerobic phase of the process. The
airflow rate may vary from about 0.5 cfm per cubic yard to about
3.0 cfm per cubic yard. The exhaust air escaping from the top of
the pile is hot (around 120-175.degree. F.), odorous, and
saturated.
[0047] The digester system 10 may further include a biofilter
system 50 in fluid communication with the top portion of the
enclosure 12 such that the air and moisture withdrawn from the pile
is transported to the biofilter 50 for exhaust treatment. For
example, as shown in FIG. 1, the exhaust may be captured and
collected by one or more exhaust fans 44 and discharged through an
air manifold 46 in fluid communication with the top portion of the
enclosure 12. The air manifold 46 is in fluid communication with a
biofilter manifold 48, which transports the exhaust to the
biofilter 50 which is used for emission or odor control. One or
more ventilation fans 51 may also be in fluid communication with
the biofilter manifold 48, which may allow ambient air to be
blended in with the exhaust before going to the biofilter 50, to
help with the temperature and moisture control of the biofilter air
entering the biofilter system 50. The biofilter manifold 48 is also
in fluid communication with a series of biofilter pipes 52, which
are disposed on or in a biofilter surface 54 surrounded by a
biofilter enclosure 56. The biofilter manifold 48 may run through
an opening formed in the biofilter enclosure 56. The biofilter
enclosure 56 is configured to hold biofilter media 58 formed around
and on top of the biofilter pipes 52. FIGS. 8A and 8B schematically
show a side-view and cross-sectional view, respectively, of one
illustrative biofilter pipe 52. As shown, each of the biofilter
pipes 52 has holes 60 that allow fluid to flow from within the
biofilter pipe 52 to an area outside of the pipe which contains the
biofilter media 58. Each of the biofilter pipes 52 may be placed on
top of the biofilter surface 54, such as shown in FIG. 9, or may be
placed within channels (not shown) formed within the biofilter
surface 54.
[0048] As known by those skilled in the art, the biofilter media 58
may be composed of various materials and layers, such as shown in
FIG. 10. For example, the biofilter media 58 may include shredded
wood and bark, preferably about 75% wood and about 25% bark. Other
acceptable green materials may include plant leaves, needles, and
grass, although preferably these are no more than about 2% by wet
weight of the biofilter media. Dimensional wood, stumps, trees,
clean plywood, and clean particle board or other materials may also
be used. Preferably, the biofilter media 58 includes at least about
60% organic matter, a maximum TKN nitrogen of no more than 0.35%, a
moisture content of between about 35 to about 60%, and combined
nitrate and ammonium concentrations that are less than about 100
ppm. The biofilter media 58 also preferably includes at least about
90% by weight of particle sizes ranging from about 1.0 to about 4.0
inches, with less than about 10% by weight of particle sizes
ranging less than about 1.0 inch and less than about 5% by weight
of particle sizes ranging greater than about 4.0 inches.
[0049] Referring again to FIG. 3, in step 150, the process further
includes temporarily removing the membrane cover 14 after aerobic
composting has been started and inserting a pile restructuring
apparatus or spike 62 in the pile 16 at designated areas and times
in order to form air shafts in the pile. The air shafts repair
uneven airflow allowing substantially uniform aerobic conditions in
the pile. As shown in FIGS. 11 and 12, the spike 62 may be mounted
on a machine 64, such as an excavator or loader, which may be
positioned around the enclosure 12. The spike 62 has a long shaft
and may include a sampling corbel 66 attached on a side of the
spike toward its end.
[0050] In operation, the machine moves around the top of the
enclosure 12 and punctures the pile with the spike 62 at designated
areas leaving vertical air shafts throughout the pile. The air
shafts may be formed in a uniform array of shafts across the pile
or in an uneven pattern, e.g., in designated areas where more
aerobic conditions are needed. For example, the air shafts may be
spaced about 6 feet apart from the center of one shaft to the
center of another. Preferably, the spike 62 is long enough so that
the air shafts are formed through at least half the height of the
pile. For example, for a pile having an initial height of about 25
feet, the spike may be about 13 feet long and have about an 8 inch
diameter. The sampling corbel 66 allows a small sample of the lower
horizon of the pile to be brought to the surface for observation
and mapping of the lower horizon. The inspection of the sample may
include a visual inspection of the moisture, color, texture, odor,
and/or temperature of the organic matter. The observations and
mapping may be recorded. This information may then be used to
adjust airflow through the pile. Forming the array of air shafts
across the pile 16 with the spike 62 may be done one or more times
during the composting phase of the process, preferably about once
for a pile having a composting process of about one month.
[0051] The use of the spike 62 allows the organic matter in the
pile 16 to have sufficient aerobic conditions for the composting
process without the need for turning (tearing down and rebuilding)
the pile. Higher porosity, volatile solids, nitrogen, and airflow
are factors that increase the rate of composting. An example is
about 1 month of residence time, an initial 160.degree. F. digester
temperature declining to 120.degree. F., and an initial bulk
density of 700-800 lbs per cubic yard at the beginning of
composting.
[0052] When a desired temperature drop has been achieved or a
desired amount of biomethane has been produced, the digestion
process is complete and the digester batch can be removed. FIG. 15
schematically shows various locations of a machine 64, such as a
track styled hydraulic excavator or loader, during pile
restructuring or removing of the organic matter at the end of the
alternating subterranean digesting process. For example, a
hydraulic excavator with approximately 30,000 lbs operating weight
and approximately 100 hp may be used. After removal, the batch can
be aged and then screened for sale as a compost or soil product.
After removal of the batch, the bottom surface 12a of the enclosure
12 and pumps may be cleaned and serviced.
[0053] The alternating digester system 210 may produce heat,
electricity, compressed natural gas, biomethane, and compost.
Preferably, the compost is further finished and/or improved in an
enclosed ventilated composting system 240 or digestate drying or
pelleting process 230. Preferably, odor is controlled in a
four-stage, series system of enclosures: biofilter, carbon filter,
and counteractant misting system in an exhaust stack 240.
[0054] Referring to FIG. 17, in another embodiment, food waste and
paper 250 from agricultural, institutional, commercial, urban, and
suburban settings may be processed in an above grade anaerobic
digestion system 260. The above grade anaerobic digestion system
260 may produce heat, electricity, compressed natural gas,
biomethane, and digestate. Preferably, the by-product digestate 270
is further finished and/or improved in an enclosed ventilated
composting system 240 or digestate drying, pelleting, or prilling
process 260. Preferably, odor is controlled in a four-stage, series
system of enclosures: biofilter, carbon filter, and counteractant
misting system in an exhaust stack.
[0055] Referring for FIG. 18, in another embodiment seasonal
landscape waste can be processed in an enclosed ventilated
composting system 240. The enclosed ventilated composting system
240 may produce heat, compost, mulch, and wood waste. Preferably,
the by-product wood waste 320 is further finished and/or improved
in a wood gasification system 330. Preferably, the mulch 440 is
further finished and/or improved in the alternating digester system
210 and/or the drying, pelleting, and prilling system 230.
Preferably, the remaining compost 280 is finished and/or improved
in the enclosed ventilation composting system 240 and/or the
drying, pelleting, prilling system 230. Preferably, odor is
controlled in a four-stage, series system of enclosures: biofilter,
carbon filter, and counteractant misting system in an exhaust
stack.
[0056] Referring to FIG. 19, in another embodiment, biosolids,
manure, and animal bedding (soiled with manure) 300 may be
processed in an enclosed ventilated composting system 240. The
enclosed ventilated composting system 240 can produce heat, compost
280, mulch 440, and/or wood waste 320. The by-product wood waste
320 may be further finished and/or improved in a wood gasification
system 330. Preferably, the remaining compost 280 is finished
and/or improved in the enclosed ventilation composting system 240
and/or the drying, pelleting, prilling system 230. Preferably, the
mulch 440 is further finished and/or improved in the alternating
digester system 210 and/or the drying, pelleting, and prilling
system 230. Preferably, odor is controlled in a four-stage, series
system of enclosures: biofilter, carbon filter, and counteractant
misting system in an exhaust stack.
[0057] Referring to FIG. 20, in another embodiment, green tree and
branch sections, and dimensional kiln-dried wood waste 320 may be
processed in a wood gasification system 330. The wood gasification
system 330 may produce heat, electricity, syngas, biohydrogen, and
biochar 440. The biochar 440 may be beneficially used in anaerobic
digestion 260 to boost biogas production and can be used in odor
control devices to remove odor from odorous exhaust airstreams. The
Biochar may also be further finished and/or improved in the
alternating digester system 210, the above grade anaerobic
digestion system 260, the drying, pelleting, prilling system 230,
and/or the enclosed ventilated composting system 240.
[0058] Referring to FIG. 21, in another embodiment packaged
un-salable food 400 may be processed in a product-package
separation system 410. The product-package separation system 410
can produce separate outputs of food waste, plastic packaging,
metal packaging, glass packaging, and digestible or compostable
paper packaging. The food waste and paper packaging 200 may be
further finished and/or improved in a subterranean alternating
digester 210, above grade anaerobic digestion system 260, and/or
enclosed ventilated composting system 240. Preferably, odor is
controlled in a four-stage, series system of enclosures: biofilter,
carbon filter, and counteractant misting system in an exhaust
stack.
[0059] Referring to FIG. 22, in another embodiment fats, oils, and
grease from cooking operations 420 can be processed in a
trans-esterification system 430. The trans-esterification system
430 can produce biodiesel fuel and glycerin. Preferably, the
by-product glycerin 450 can be further finished and/or improved in
a subterranean alternating digester 210, above grade anaerobic
digestion system 260, or enclosed ventilated composting system 240.
Preferably, odor is controlled in a four-stage, series system of
enclosures: biofilter, carbon filter, and counteractant misting
system in an exhaust stack.
[0060] Referring to FIG. 23, in another embodiment digestate,
compost, or biochar 440 may be processed in a drying, pelleting,
prilling system 230. The drying, pelleting, prilling system 230 may
produce powdered fertilizer, pellets for soil amendment,
filtration, or fuel, or prill for soil amendment. Preferably, the
pellets are used in odor control devices to remove odor from
odorous exhaust airstreams. Preferably, odor is controlled in a
four-stage, series system of enclosures: biofilter, carbon filter,
and counteractant misting system in an exhaust stack.
[0061] A person having ordinary skill in the art will understand
that, in any of the embodiments described above and any obvious
variation thereof, any non-saleable or by-products can be reused in
an appropriate system until saleable material has been obtained
and/or by-product can no longer be used in a subsequent mode.
* * * * *