Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
  • C10B45/00—Other details
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
  • C10L5/00—Solid fuels
  • C10L5/40—Solid fuels essentially based on materials of non-mineral origin
  • C10L5/44—Solid fuels essentially based on materials of non-mineral origin on vegetable substances
  • C10L5/447—Carbonized vegetable substances, e.g. charcoal, or produced by hydrothermal carbonization of biomass
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B15/00—Layered products comprising a layer of metal
  • B32B15/14—Layered products comprising a layer of metal next to a fibrous or filamentary layer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B15/00—Layered products comprising a layer of metal
  • B32B15/18—Layered products comprising a layer of metal comprising iron or steel
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B15/00—Layered products comprising a layer of metal
  • B32B15/20—Layered products comprising a layer of metal comprising aluminium or copper
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B3/00—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form
  • B32B3/26—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids ; characterised by an apertured layer
  • B32B3/266—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids ; characterised by an apertured layer characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
  • C10B49/00—Destructive distillation of solid carbonaceous materials by direct heating with heat-carrying agents including the partial combustion of the solid material to be treated
  • C10B49/02—Destructive distillation of solid carbonaceous materials by direct heating with heat-carrying agents including the partial combustion of the solid material to be treated with hot gases or vapours, e.g. hot gases obtained by partial combustion of the charge
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10B—DESTRUCTIVE DISTILLATION OF CARBONACEOUS MATERIALS FOR PRODUCTION OF GAS, COKE, TAR, OR SIMILAR MATERIALS
  • C10B53/00—Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form
  • C10B53/02—Destructive distillation, specially adapted for particular solid raw materials or solid raw materials in special form of cellulose-containing material
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
  • C10L9/00—Treating solid fuels to improve their combustion
  • C10L9/08—Treating solid fuels to improve their combustion by heat treatments, e.g. calcining
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2262/00—Composition or structural features of fibres which form a fibrous or filamentary layer or are present as additives
  • B32B2262/10—Inorganic fibres
  • B32B2262/108—Rockwool fibres
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E50/00—Technologies for the production of fuel of non-fossil origin
  • Y02E50/10—Biofuels, e.g. bio-diesel
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E50/00—Technologies for the production of fuel of non-fossil origin
  • Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel

Definitions

• Biochar production is an age-old technique that utilizes partial combustion of a woody fuel source in an oxygen starved environment to convert the rest of the wood to charcoal. Biochar is useful as a renewable energy feedstock, among other applications.
• Established biochar production processes e.g. the Missouri kiln, Brazilian beehive kiln, Slope type kiln) typically have the following features:
• Wood is piled inside a large enclosure made of an air impermeable material.
• a blanket in one aspect, includes a material having the following properties:
• thermal insulation such that the blanket is capable of withstanding temperatures of from 100 to 1000 degrees C;
• the blanket can be folded over on itself for storage; wherein the blanket is configured to conformally cover a combusting biomass to facilitate pyrolysis or drying of the biomass.
• a method is provided to produce biochar or dry biomass.
• the method includes the steps of:
• FIGURE 1 is a schematic illustration of a representative blanket covering a combusting biomass in accordance with aspects of the present disclosure
• FIGURES 2-4 are schematic illustrations of representative blankets in accordance with aspects of the present disclosure.
• FIGURE 5 is a schematic illustration of air flow and heat movement in relation to a representative blanket covering a combusting biomass in accordance with aspects of the present disclosure
• FIGURE 6 is a theoretical temperature profile through a thickness of a representative blanket from a hot side near a combusting biomass to a cool side furthest from the combusting biomass in accordance with aspects of the present disclosure
• FIGURE 7 is a photograph of an exemplary blanket having three layers in accordance with aspects of the present disclosure.
• FIGURES 8A and 8B are visual (8A) and thermal (8B) images of a representative blanket covering a combusting biomass in accordance with aspects of the present disclosure.
• the disclosed embodiments are operable to produce biochar from a biomass or to dry a biomass through controlled heating. While prior art technologies are stationary enclosures, the embodiments provided herein are based on a portable, flexible laminated blanket that is draped over a biomass (e.g., a wood slash pile). In this way, the blanket functions as a portable and reusable kiln for pyrolyzing biomass into biochar or drying biomass. As used herein, the term "biomass" refers to any biomass known to those of skill in the art, and includes naturally occurring carbon sources.
• a blanket in one aspect, includes a material having the following properties:
• thermal insulation such that the blanket is capable of withstanding temperatures of from 100 to 1000 degrees C;
• the blanket can be folded over on itself for storage; wherein the blanket is configured to conformally cover a combusting biomass to facilitate pyrolysis or drying of the biomass.
• the combination of these properties is unique because it provides almost identical functionality as the brick and mortar used in stationary kilns, but because the material is flexible it provides a means to economically convert remote slash piles (e.g., at logging sites) into biochar.
• a representative blanket 105 is schematically illustrated covering a combusting biomass 110 resting on a surface 115 (e.g., dirt).
• the blanket 105 can be any blanket having the above-listed properties. Various embodiments of the blanket 105 are described further below.
• the blanket 105 is a thermal insulator.
• the combusting biomass 110 may have a temperature of from 100 to 1000 degrees C, and in certain embodiments the blanket 105 withstands heat (i.e., maintains structural stability) across this range.
• the blanket 105 is capable of withstanding temperatures of from 200°C to 650°C (e.g., for pyrolyzing biomass).
• the blanket 105 is capable of withstanding temperatures of from 100°C to 250°C (e.g., for drying biomass).
• the blanket 105 is also gas impermeable so as to prevent combustion fuel gasses to diffuse through the blanket 105.
• gas impermeable defines a material that allows negligible oxygen diffusion through its thickness. By preventing gas diffusion, and particularly oxygen diffusion, the blanket 105 limits fuel to the combusting biomass 110 covered by the blanket 105. Because oxygen cannot pass through the blanket 105, the only oxygen provided to the combusting biomass must pass around the blanket 105.
• a plurality of air vents 120 are disposed peripherally on the blanket 105, wherein the plurality of air vents are configured to provide controllable air flow to pyrolyzing or drying biomass disposed beneath the blanket.
• the air vents 120 are positioned in the blanket 105 to provide controllable air flow to the combusting biomass 110.
• the blanket 105 allows a user to pyrolize the biomass into biochar instead of combusting it into ash.
• air from outside the blanket only reaches the biomass by passing around the periphery of the blanket.
• the blanket 105 is also flexible, such that it can be folded over on itself for storage. By being flexible, it can be transported easily so as to facilitate pyrolysis of biomass in remote locations, such as logging sites and the like. Flexibility also allows the blanket 105 to conformally cover a combusting biomass 110. This allows the headspace between the blanket 105 and the combusting biomass 110 to be minimized, which facilitates pyrolysis and generally allows a user to control the temperature of the combusting biomass 110.
• the blanket 105 can similarly be used to dry the biomass, if the temperature is controlled properly, as will be discussed in more detail below.
• Biomass drying is accelerated as the temperature of the biomass is elevated.
• Control of the oxygen flow under the blanket e.g., via vent
• the blanket enables the warm combustions gases to circulate prior to exiting the blanket, thereby raising the temperature of the biomass.
• All but the most tightly bound water (generally less than 10% by weight) is liberated from the biomass as the temperature approaches 100°C, the boiling point of water.
• the blanket 105 consists of a single layer 205 having all of the required properties.
• the blanket 105 will have a "hot" side nearest the combusting biomass 110, and a “cool” side furthest from the combusting biomass 110.
• the blanket comprises a thermal insulation layer capable of withstanding temperatures of from 100 to 1000 degrees C; and a gas impermeable layer that is a different material than the thermal insulation layer, wherein the thermal insulation layer is disposed closer to the combusting biomass than the gas impermeable layer.
• the blanket 105 comprises two layers: A thermal insulation layer 305, on the hot side, and a gas impermeable layer 310 on the cool side.
• the combination of the two layers (305 and 310) provides all of the required properties.
• the thermal insulation layer 305 comprises a ceramic material.
• the ceramic material is selected from the group consisting of ceramic pressed particulate paper and woven ceramic fibers (e.g., basalt).
• the gas impermeable layer 310 is a metal foil.
• the metal foil is selected from the group consisting of stainless steel foil, aluminum foil, or other refractory metals and alloys foils from them.
• the blanket has the additional property of durability, such that the blanket is not structurally damaged after repeated exposure to temperatures of from 100 to 1000 degrees C.
• a three (or more) layer blanket 105 is provided.
• a first protective layer 410 is provided that confers the property of durability. The first protective layer 410 is disposed closest to the combusting biomass 110.
• the protective layer 410 protects any of the other layers of the blanket 105 from being compromised (e.g., by ripping or puncturing) while in use. This is particularly desirable if the thermal insulation layer 305 is a ceramic material, which are typically fragile. Small holes in the blanket can serve as nucleation sites for larger tears and rips to form, which reduces reusability of the blanket.
• the first protective layer is a metal mesh layer. In a further embodiment, the metal mesh layer is a stainless- steel mesh layer.
• An optional second protective layer 415 can be added to provide durability to both the hot and cool sides of the blanket 105 for maximum durability.
• the second protective layer 415 can be the same or different in composition as the first protective layer 410.
• a method is provided to produce biochar or dry biomass.
• the method includes the steps of:
• the biomass is pyrolized at a temperature of from about 200°C to 650°C. In one embodiment, the biomass is dried at a temperature of from about 100°C to 250°C.
• the step of maintaining the temperature of the biomass covered by the blanket for a sufficient time to produce biochar or dry biomass comprises adjusting the amount of air flowing to the biomass at least once. In one embodiment, adjusting the amount of air flowing to the biomass comprises moving a peripheral edge of the blanket to increase or decrease airflow or operating peripheral vent ports.
• the first prototype was a semipermeable ceramic material.
• the blanket provided multiple functions: (1) Capture and redistribute heat generated in the local regions of combustions, and (2) permit hot volatile off-gas to vent slowly out of the pile.
• the blanket was made from a high-temperature semi-permeable ceramic fiber blanket material. This material is by its very nature a very good insulator because it is made of woven basalt fibers, which have a low thermal conductivity.
• the gas permeability of the blanket was also within a range that was expected to be functionally appropriate for the scale of the biomass pile that was targeted for pyrolysis (200 lbs of green wood).
• a semi-permeable barrier is effective at suppressing combustion but not easily sealed when the wood is done carbonizing and the process needs to be "shut-off" such that the biochar can be collected.
• Free convection of volatile/heated gases is a significant factor in design of inlets and outlets and providing heat throughout the pile to affect wood conversion.
• Orifice diameter should be something that is controllable because as more biochar is produced, it needs to be adjusted to maintain a constant temperature within the pile.
• a semi-permeable barrier is not suitable to produce biochar on a large scale because its combustion cannot be effectively stopped.
• Metal mesh is effective at providing durability and added structure to the blanket to make more complicated geometries over the wood possible.
• the first change was to incorporate a metal foil into the laminate. This foil serves to reflect radiative heat, but most importantly, provides an air impermeable layer behind the ceramic fiber insulation to stop permeation of air through the blanket.
• This laminate design is shown in FIGURES 4 and 7.
• the foil is placed such that it is on the cool side of the blanket as its melting point is rather low compared to the expected operating temperatures.
• Impermeable layer is critical to the ability to mediate temperature under the blanket, but also to recovering the biochar after the pyrolysis is completed. Without this layer, air will continually permeate into the biochar, potentially maintaining sufficient combustion to lose the entire product if not actively quenched.
• the use of an impermeable material also required reconsideration of how to control airflow into the pile.
• controllable inlets and outlets were been placed radially around the blankets bottom in order to drive the buoyant convection that results in good mixing within the pile. A simple schematic of this design is shown in FIGURE 5.
• FIGURE 6 is a theoretical temperature profile through a thickness of a representative blanket from a hot side near a combusting biomass to a cool side furthest from the combusting biomass in accordance with aspects of the present disclosure.
• FIGURE 7 is a photograph of an exemplary blanket having three layers: a ceramic fiber thermal insulation layer, an aluminum foil gas impermeable layer, and a stainless steel mesh protective layer.
• FIGURES 8A and 8B are visual (8A) and thermal (8B) images of a representative blanket covering a combusting biomass.
• thermal image in FIGURE 8B registers a temperature of 166°C on the cool side of the blanket, indicating a relatively low temperature (estimated to be about 300°C) on the hot side of the blanket, which is conducive to pyrolysis of the biomass into biochar.

Landscapes

• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Combustion & Propulsion (AREA)
• Materials Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Sustainable Development (AREA)
• General Chemical & Material Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Processing Of Solid Wastes (AREA)
• Solid Fuels And Fuel-Associated Substances (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=47140058

Family Applications (1)

Country Status (3)

Families Citing this family (2)

Family Cites Families (13)

• 2012
  • 2012-05-14 US US14/115,060 patent/US20140075835A1/en not_active Abandoned
  • 2012-05-14 EP EP12782781.4A patent/EP2707463A4/de not_active Withdrawn
  • 2012-05-14 WO PCT/US2012/037829 patent/WO2012155145A2/en not_active Ceased

Also Published As

Similar Documents

Legal Events