CA2907084A1

CA2907084A1 - Composite carbonaceous fuel compact

Info

Publication number: CA2907084A1
Application number: CA2907084A
Authority: CA
Inventors: Robert L. Heimann
Original assignee: Enginuity Worldwide LLC
Current assignee: Enginuity Worldwide LLC
Priority date: 2013-03-15
Filing date: 2014-03-14
Publication date: 2014-09-18
Also published as: EP2970804A1; WO2014144051A1; US20130212935A1; JP2016518477A; KR20160018464A; BR112015024216A2; CN105164236A; AU2014227899A1

Abstract

A carbonaceous compact is provided by the present disclosure that includes a body having a partially or fully carbonaceous biomass composition and an adhesive additive. The adhesive additive includes a starch and a hydroxide. The porous nature of the carbonaceous material provides means for nutrient retention or filtering means. Carbon is activated through chemical or thermal reaction from pyrolyzed wood/nut. A method of processing the carbonaceous compact is also provided that comprises combining a composition of combustible biomass materials, drying the composition, adding the adhesive additive, adding any further additivies, such as silica 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 formed at about 500°C so that biochar is formed, while processing above 518°C - 572°C carbon is formed with subsequent activation.

Description

Attorney PCT/US2014/028298 5 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 Attorney PCT/US2014/0282985 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 Attorney PCT/US2014/0282985 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.

Attorney PCT/US2014/028298 5

[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 Attorney PCT/US2014/028298 5 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 Attorney PCT/US2014/028298 5

[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 Attorney PCT/US2014/028298 5 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.

Attorney PCT/US2014/028298 5

[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.

Attorney PCT/US2014/028298 5

[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.

Claims

What is claimed is:

1. A carbonaceous compact comprising:
a body comprising:
a carbonaceous biomass composition; and an adhesive additive comprising:
a starch; and a hydroxide.

2. The carbonaceous compact according to Claim 1, wherein 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.

3. The carbonaceous compact according to Claim 1 further comprising at least one of a silicate additive, a viscosity additive, beneficial bacteria.

4. The carbonaceous compact according to Claim 1, wherein the biomass composition is selected from the group consisting of 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.

5. The carbonaceous compact according to Claim 1 comprising, by percent weight:
69 - 98% biomass composition;
1 - 30% starch; and less than 1% hydroxide.

6. The carbonaceous compact according to any of Claims 1 or 3, wherein the body has an upper portion, a lower portion, and tapered walls extending from the upper portion to the lower portion, wherein the upper portion is wider than the lower portion.

7. The carbonaceous compact according to Claim 6, wherein the body further comprises rounded edges.

8. The carbonaceous compact according to any of Claims 1 or 3, wherein the body comprises parallel opposed sidewalls and parallel opposed end walls, and at least one of the sidewalls defines a flat surface.

9. The carbonaceous compact according to any of Claims 1, 3, 6, or 8, wherein the body is selected from the group consisting of a pellet, a briquette, and a puck.

10. A carbonaceous compact comprising:
a combustible biomass composition; and an adhesive additive comprising at least one of a starch and a hydroxide.

11. The carbonaceous compact according to Claim 10, wherein 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.

12. The carbonaceous compact according to Claim 10 further comprising at least one of a silicate additive and beneficial bacteria.

13. The carbonaceous compact according to Claim 10, wherein the carbonaceous compact comprises, by percent weight:
90 - 95% biomass; and - 10% adhesive additive.

14. A carbonaceous compact comprising:
a body comprising:
a combustible biomass composition;
an adhesive additive comprising:
a starch; and a hydroxide;
a silicate additive; and beneficial bacteria.

15. The carbonaceous compact according to Claim 14, wherein the carbonaceous compact comprises, by percent weight:
50 - 95% biomass;
- 50% starch;
0.005 - 0.05% hydroxide;
0.1 - 5% silicate additive; and 0.1 - 2% bacteria.