Note: Descriptions are shown in the official language in which they were submitted.
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COMPOSITE CARBONACEOUS FUEL COMPACT
[0001] The
present disclosure generally relates to bio-char and carbon from
biomass sources and methods of processing thereof. The present disclosure also
relates
to carbonaceous sources, and in particular, resources that do not depend on
coal tar and
that reduce emissions of "greenhouse gas" carbon dioxide into the atmosphere.
Finally,
the present disclosure relates to manufacturing processes for creating
carbonaceous
biomass into biochar or carbon.
[0002] Most carbon produced for filtering applications is made from coal tar.
Wood is not
used in aqueous filtering applications due to iron content. With the recent
emphasis on
renewable energy sources, efforts have been made in the art to create so-
called "biomass"
materials, in which a bio-char and carbon combination of nutshell and waste
are combined
and processed to create an energy resource to take the place of, or be
combined with, for
example, coal. Biochar can sequester carbon dioxide. Bio-char is produced from
any
biomass source through low temperature carbonization termed "pyrolysis" or
"low
temperature roasting" at around 500 C, while carbon is produced by pyrolysis
or high
temperature roasting above 518 C to 572 C with subsequent activation.
[0003] With the recent emphasis on Green" sources, efforts have been made in
the art to
create so-called "biomass" materials, in which a combustible combination of
waste, such as
wood chips or sawdust, along with certain additives, are combined and
processed to create
a carbonaceous resource that can take the place of coal tar. These devices use
compression to force wood particles through metal dies or molds. In some
machines,
pressure is applied discontinuously by the action of a piston on material
packed into a
cylinder. The equipment may have a mechanical coupling and fly wheel or
utilize hydraulic
action on the piston.
[0004] Known biomass materials have included natural lignins of the
constituent materials
in order to bind the materials together during the manufacturing process, in
order to create
a burnable mass. Natural lignins, for example from various wood sources, are
complex
natural polymers resulting from oxidative coupling of,
primarily, 4-
hydroxyphenylpropanoids. Additionally, other materials such as thermoplastic
resins have
been added in the manufacturing process to bind the constituent materials
together.
[0005] However, these natural lignins and thermoplastic binders are carbonized
resulting
in pellets that are not durable for transport or other processing operations,
especially using
known manufacturing techniques such as those set forth above. As a result,
various
biomass forms suffer from chronic crumbling and dust generation during
production and
downstream handling. Significant amounts of dust can become an explosive
issue, and
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thus current binders in the art may ultimately cause safety hazards. As a
further
disadvantage of known binders, product uniformity is an issue, with irregular
lengths and
ragged cuts, which further add to the dust problem. As with other materials,
such as
switchgrass, forest litter, paper waste, cane waste, and the like, product
quality is reduced,
and the dust issue often becomes more aggravated. Additionally, some of the
known
binders generate gases during the burning process that are environmentally
undesirable,
and in fact, some of the binders are not completely combusted during the
burning process.
Therefore, current manufacturing processes, and the materials used therein,
create
carbonaceous forms that are not durable and that cause issues in their
manufacture and
downstream handling.
BRIEF SUMMARY OF THE INVENTION
[0006] In one
form of the present disclosure, a carbonaceous compact is provided
that comprises a body having a combustible biomass composition and an adhesive
additive, wherein the adhesive additive comprises a starch and a hydroxide.
[0007] In
another form, a carbonaceous compact is provided that comprises
biomass composition and an adhesive additive. The adhesive additive comprises
at least
one of a starch and a hydroxide.
[0008] In
variations of these carbonaceous compacts, the hydroxide is selected
from the group consisting of alkali metal hydroxides, alkaline earth
hydroxides, sodium
hydroxide, potassium hydroxide, calcium hydroxide, lithium hydroxide, and
caustic soda.
Further additives may also include a silicate additive, (which may be a liquid
or powder
form), and beneficial bacteria. Low temperature bio-char cannot use grass,
which is a high
cellulose material.
Additionally, various geometries and compositions for the
carbonaceous compacts are also provided by the teachings of the present
disclosure.
[0009]According to another aspect of the present disclosure, a method of
processing a
biomass carbonaceous compact is provided that comprises combining a
composition of
biomass materials, comminuting the composition of biomass materials, adding an
adhesive
to the biomass materials to form a composite biomass, the adhesive comprising
a starch
and a hydroxide, and forming the composite biomass into a shapeform.
[0010] In another form, a method of processing a biomass carbonaceous compact
is
provided that comprises combining a composition of biomass materials, adding
an
adhesive to the biomass materials to form a composite biomass, the adhesive
comprising a
starch and a hydroxide, and forming the composite biomass into a carbonaceous
shapeform.
[0011] In still another form, a method of processing a biomass carbonaceous
compact is
provided that comprises combining a composition of biomass materials,
comminuting the
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composition of biomass materials, drying the comminuted composition of biomass
materials, performing partial or full pyrolysis or roasting adding an adhesive
to the biomass
materials, the adhesive comprising a starch and a hydroxide, adding a silicate
to the
composition of biomass materials, adding beneficial bacteria to form a
composite biomass,
forming the composite biomass into a shapeform, and partitioning the composite
biomass
shapeform into individual pieces that are compatible with existing material
handling. The
processing is performed at lower temperatures such that an endothermic
reaction of the
biomass materials and adhesive results or in exothermic ranges followed by
activation.
[0012] Further
areas of applicability will become apparent from the description
provided herein. It should be understood that the description and specific
examples are
intended for purposes of illustration only and are not intended to limit the
scope of the
present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In
order that the disclosure may be well understood, there will now be
described various forms thereof, given by way of example, reference being made
to the
accompanying drawings, in which:
[0014] FIG. 1
is a perspective view of various geometric forms of a body of a
carbonaceous compact constructed in accordance with the principles of the
present
disclosure;
[0015] FIG. 2A
is a perspective view of an alternate form of a body for the
carbonaceous compact in accordance with the principles of the present
disclosure;
[0016] FIG. 2B
is a front view of the alternate form of the body for the
carbonaceous compact of FIG. 2A accordance with the principles of the present
disclosure;
[0017] FIG. 2C
is a side view of the alternate form of the body for the
carbonaceous compact of FIG. 2A accordance with the principles of the present
disclosure;
and
[0018] FIG. 3
is a process flow diagram illustrating the various steps and forms of
the manufacturing processes according to the teachings of the present
disclosure
[0019] The
drawings described herein are for illustration purposes only and are not
intended to limit the scope of the present disclosure in any way.
DETAILED DESCRIPTION
[0020] The
following description is merely exemplary in nature and is not intended
to limit the present disclosure, application, or uses. It
should be understood that
throughout the description, corresponding reference numerals indicate like or
corresponding parts and features.
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[0021]
According to the principles of the present disclosure, a carbonaceous
compact is provided that comprises a body, which may be in any shape or form,
such as
the exemplary forms shown in FIG. 1. As indicated, the body 10 may be in the
form of a
pellet, a briquette, or a puck. A pellet may be defined by a having a size on
the order of
about 4.0 to 7.6 mm. Alternatively, a typical briquette may have a length and
width of
about 101.6 mm (4 inches) and 76.2 mm (3 inches), respectively. Alternatively,
a puck
may have a diameter between about 25.4 mm (1 inch) and 100.8 mm (4 inches). It
should
be understood that these geometric forms are merely exemplary and thus they
should not
be construed as limiting the scope of the present disclosure.
[0022] The
body 10 comprises a carbonaceous biomass composition that can
essentially be any biomass materials, or combination of biomass materials,
and/or their use
waste. By way of example, these materials may include saw dust, cardboard and
chipboard, grass, switchgrass, energy crops, hay, tree bark, sweetgum seed
pods,
pinecones, newsprint, wheat straw, duckweed, pine needles, mixed leaves, yard
waste,
agricultural waste, cotton waste, grape and wine offal, corn stover, crop
stovers, peat,
tobacco waste, tea waste, coffee waste, food processing waste, food packaging
waste, nut
meats and shells, chestnut hulls, pecan shells, paper waste, pallets, egg
cartons, animal
waste, livestock waste, mammal waste, and bone.
[0023]
Advantageously, the carbonaceous compact is highly durable do to its
inventive adhesive additive. Generally, the carbonaceous compact uses a Stein
Hall type
adhesive made from starch, or any other suitable material to replace the
natural lignins as
set forth above. In a Stein Hall adhesive, about 5% to 20% of the total starch
content is
gelatinized into a high viscosity paste called primary starch. The remainder
of the starch
(about 80% to 90%) stays ungelatinized and is called secondary starch. The
starch may
be one produced from wheat, oats, rice, corn, wheat middling, wheat waste or
even wood
and the like, but containing a gelatinized fraction that upon substantial
drying will tightly
bond the biomass composition.
[0024]
Additionally, the adhesive additive includes a hydroxide. The hydroxide may
be, for example, alkali metal hydroxides, alkaline earth hydroxides, sodium
hydroxide,
potassium hydroxide, calcium hydroxide, lithium hydroxide, and caustic soda,
among
others. The synergistic combination of starch and hydroxide provide a highly
durable
carbonaceous compact, in which any number of constituent biomass materials may
be
used, without relying on any natural lignins or other undesirable binders.
[0025] In one
form, the innovative adhesive is provided to bind the constituent
biomass composition and also to form a substantially continuous shell around
the exterior
portion of the fuel compact. With this shell, the carbonaceous compact
according to the
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present disclosure is highly durable and significantly reduces the traditional
dust issues
associated with biomass compositions, as set forth above.
[0026] In one exemplary composition of the present disclosure, the
carbonaceous
compact comprises, by percent weight, about 69 - 98% biomass composition,
about 1 -
30% starch, and less than 1% hydroxide. Another composition is about 90 - 95%
carbonaceous biomass and about 5 - 10% of the inventive adhesive additive.
[0027] Further additives are also provided by the present disclosure,
which may
include, by way of example, a silicate additive, (which may be a liquid or
powder form).
The silicate additive is included to provide added weather resistance and
hydrogen
bonding of carbonaceous biomass particles. The silicate may include sodium,
potassium,
or lithium, or mixtures of these three, in one form of the present disclosure.
Bacteria may
be added. Bacteria are used to inoculate crops that sequester nitrogen from
the air.
Bacteria "Aspergillus Niger" or "arbuscular mycorrhizal fungi" breaks down
biomass to
element products releasing minerals for plant uptake Calcium (Ca), Magnesium
(Mg),
Phosphorus (P) and Potassium (K). In another form, the preservative may
include sodium
tetraborate or borax containing compounds at a concentration of about 1 to
about 5%, and
more particularly, about 1 to about 2%. Moreover, sodium silicate may be added
to
improve water repellency.
[0028] The additives may also include materials that will benefit from
the
sequestering of carbon and nitrogen in soils. When calcium hydroxide is used
as a source
of hydroxide, it may react to form calcium silicate, which scavenges sulfur
dioxide and
nitrous oxides in air emissions from combustion in flue gas. When lithium
hydroxide is
used, it may react and form lithium silicate, which forms a zeolite capable of
sequestering
carbon dioxide from biogenic process.
[0029] In a further exemplary composition, the carbonaceous compact
comprises
about 50 - 95% biomass, about 5 - 50% starch, about 0.005 - 0.05% hydroxide,
about 0.1 -
5% silicate additive, and about 0.1 - 2% bacteria. Further compositions
according to the
teachings of the present disclosure are set forth below in Table 1, with an
exemplary target
value for one biomass composition that comprises grass, corn stover, or a
mixture thereof,
according to the teachings of the present disclosure:
Biomass Starch Hydroxide Silicate
Range 50-90% 5-50% 0.005-0.05% 0-5%
Target 60 10 0.02 2.5
[0030] Table 1
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[0031]
Referring now to FIGS. 2A ¨ 2C, one innovative form of the body for the
carbonaceous compact is illustrated and generally indicated by reference
numeral 20.
Generally, the body is modeled after a kernel of corn, which has a hard outer
shell, is
transportable, and has relatively flat sides, as well as an advantageous
aspect ratio in
order to be highly durable for handling and downstream operations.
[0032] As
shown, the body 20 has an upper portion 22, a lower portion 24, and
tapered sidewalls 26, 28, 30, and 32 extending from the upper portion 22 to
the lower
portion 24, wherein the upper portion 22 is wider than the lower portion 24.
In one form,
the body 20 comprises rounded edges 34 as shown, in order to provide increased
durability. The tapered sidewalls 26 and 28 are generally parallel and opposed
as shown,
as are the tapered walls 30 and 32. At least one of the tapered sidewalls 26,
28, 30, and
32 defines a flat surface in one form of the present disclosure. It should be
understood that
this geometry, along with the pellet, puck, and briquette as previously set
forth, are merely
exemplary and should not be construed as limiting the scope of the present
disclosure.
[0033]
Accordingly, a composite carbonaceous compact is provided by the present
disclosure that is durable, that reduces the amount of dust normally
associated with known
biomass compositions, that is lower cost, higher efficiency.
[0034] Various
forms of composite carbonaceous compacts described herein were
tested for durability per the American Society of Agricultural and Biological
Engineering
ASABE S269.4, Dec1991 (R2007) Sec. 5 Durability test standard. A "GAMET"
Pellet
durability test was utilized to run the testing experiments for 10 minutes @
50 rpm at room
temperature. A Pellet Durability Index (PDI) was defined by dividing the
weight of the
compacts before and after testing. After testing, the compacts are screened
and the
remaining whole compacts are weighted. The starting weight is standardized at
500 grams.
The PDI equals the remainder after testing divided by 500 multiplied by 100 to
arrive at a
percentage.
[0035] Biochar
soil management can deliver tradable carbon emissions reduction.
Pyrolyzed wood particles produced in accordance with the teachings of the
present
disclosure are in the form of 7.6 mm pellets having a PDI of 98% and
incorporate individual
particles with sizes ranging from 3.175 mm ¨ 0.127 mm (0.125 - 0.005 inches).
Biochar
can sequester carbon dioxide.
[0036]
According to another aspect of the present disclosure, a method of
processing a biomass carbonaceous compact is provided that includes comprising
combining a composition of combustible biomass materials, comminuting the
composition
of biomass materials, drying the comminuted composition of biomass materials,
and
adding an adhesive to the biomass materials, the adhesive comprising a starch
and a
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hydroxide. Further additives are also provided, which include a silicate and
beneficial
bacteria. The composite biomass is processed into a shapeform, and then the
shapeform
is partitioned into individual pieces that are compatible with existing
handling methods. In
one form the processing is performed at about 500 C so that biochar is formed,
while
processing above 518 C-572 C carbon is formed with subsequent activation.
[0037]
Referring now to FIG. 3, manufacturing steps for processing a biomass
carbonaceous compact, and variations thereof, are shown. It should be
understood that
these steps may be carried out in order as shown, or alternately, in a
different order.
Therefore, the order of the steps illustrated should not be construed as
limiting the scope of
the present disclosure. In one form, the method of processing a biomass
carbonaceous
compact comprises combining a composition of biomass material(s). These
biomass
materials are essentially any combustible material, or combination of
combustible
materials. For example, these materials may include saw dust, cardboard and
chipboard,
grass, hay, tree bark, sweetgum seed pods, pinecones, newsprint, wheat straw,
duckweed,
pine needles, mixed leaves, yard waste, agricultural waste, cotton waste,
grape and wine
offal, corn stover, crop stovers, peat, tobacco waste, tea waste, coffee
waste, food
processing waste, food packaging waste, nut meats and shells, chestnut hulls,
peacan
hulls, paper waste, pallets, and egg cartons, among others. Other combustible
materials
may also be employed, and thus these biomass materials should not be construed
as
limiting the scope of the present disclosure.
[0038] Next,
these biomass materials may be comminuted, or crushed, to a particle
size that is compatible with the specific process, and also with other
additives and various
processing steps, as set forth in greater detail below. The comminuted
composition of
biomass materials may next be dried, or alternately, the comminuted
composition of
biomass materials may be roasted before entering a forming step, again
depending on a
variety of processing parameters. For example, if a tree or wood products were
used as
part of the biomass composition, then the comminuting step would take these
materials
down to a sawdust form. The comminution process may be carried out, for
example, by
tub grinders, horizontal grinders, hammer mills, burr mills, or shredders,
among others.
Each type of biomass material will have a different derived particle size from
the
comminuting step. Generally, particle size requirements are based on desired
throughput
rates. In one form of the present disclosure, a particle size that is about 20
to about 40%,
and more particularly about 30%, of the die opening/diameter used to produce
the desired
shapeform. These particle sizes facilitate flow rates without excessive
processing back-
pressure.
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[0039]The biomass materials are dried before entering the forming step, a
moisture
content of about 8% to about 20%, and more specifically about 12%, is typical
for many
types of biomass materials. In one form of the present disclosure, the drying
is performed
by low cost solar collector troughs that concentrate solar energy and heat
suitable thermal
mediums such as oil, antifreeze, water, or a mixture thereof, for transmission
of heat
energy through liquid to air heat exchangers. Alternately, geothermal drying
may be
employed, alone or in combination with gas-fired or electric drying processes.
Drying
equipment may also be conventional grain drying batch hoppers, bins, or silos,
or higher
throughput horizontal dryers. Further still, heat may be transferred through a
passive floor
heating system. In yet another form, single or multiple desiccant beds may be
employed to
remove moisture from the drying air. It should be understood that these drying
methods
are merely exemplary and thus should not be construed as limiting the scope of
the
present disclosure.
[0040] An
advantageous step of the present disclosure involves adding an
adhesive to the biomass materials, wherein the adhesive comprises a starch and
a
hydroxide. This combination of the combustible biomass composition and the
adhesive
additive, along with other additives as described below and herein. In
addition to the
adhesive, further additives are also provided within the manufacturing
process. These
additives include, by way of example, a silicate and beneficial bacteria
[0041] After
or during the introduction of additives, the composite biomass is
formed into a shapeform. In one form of the present disclosure, the forming
step is
performed by an extrusion process in which the forming is performed by an
extruder, a
cuber, or a pellet mill. Other manufacturing processes may also be employed,
including
but not limited to compression molding, plunger molding, and die forming.
Therefore, the
extrusion process should not be construed as limiting the scope of the present
disclosure.
In one desired form of the present disclosure, the extruder premixes,
extrudes, and cuts to
length a composite biomass carbonaceous compact at about 500 to about 30,000
pounds
per hour.
[0042] In one
form, the innovative adhesive is added at a throat portion of the
extruder, cuber, or mill. Alternately, the adhesive is added in a hopper
portion of the
extruder, cuber, or mill. In still another form, the adhesive is added in a
die portion of the
extruder, cuber, or mill and is configured to coat an exterior surface area of
the composition
of biomass materials. The adhesive may be further divided within the
processing step,
wherein the starch is mixed with the biomass composition prior to forming, and
the
hydroxide is added during the forming.
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[0043] With
plunger molding, in one form the adhesive is added between wads of
the plunger. Alternately, the adhesive is added at a plunger input and is
configured to coat
an exterior surface area of the composition of biomass materials at an exit
die.
[0044] It is
further contemplated that a mechanical briquetting process, such as the
Brik Series by Dipiu Macchine Impianti; BHS Energy LLC; Wyoming, PA.; Warren &
Barrg,
Duapi, CA; or California Pellet Mill, Indianapolis, IN. may also be employed
in accordance
with the teachings of the present disclosure.
[0045] The
shapeform of the composite biomass may be any number of geometric
configurations, including but not limited to pellets, briquettes, pucks, and
the corn kernel
configuration.
[0046] After
the composite biomass is produced as a shapeform, it is partitioned
into individual pieces. The individual pieces may be the same size, or of
varying
sizes/lengths. In one form, the individual pieces are compatible with existing
material
handling.
[0047] In one
form of the present disclosure, the processing is performed at lower
temperatures such that an endothermic reaction of the biomass materials and
adhesive
results. These temperatures are in the range of about 480 C to about 500 C for
a roasting
process, and similarly, 518 C - 572 C depending on the type of carbon material
desired.
Alternatively, the method may be performed at exothermic conditions followed
by
activation.
[0048] It
should be noted that the invention is not limited to the various forms
described and illustrated as examples. A large variety of modifications have
been
described and more are part of the knowledge of the person skilled in the art.
These and
further modifications as well as any replacement by technical equivalents may
be added to
the description and figures, without leaving the scope of the protection of
the disclosure
and of the present patent.
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