Biomass pyrolysis integrated with bioreduction of metal ore, hydrogen production, and / or activated carbon production.

Abstract

Improved processes and systems for producing renewable hydrogen suitable for reducing metal ores and for producing activated carbon are disclosed. Some variations provide a process that includes pyrolyzing biomass to produce a carbon-containing bio-reagent and a pyrolysis off-gas, converting the pyrolysis off-gas to additional reducing gas and / or heat, reacting at least a portion of the bio-reagent with a reactant to produce the reducing gas, and chemically reducing metal oxides in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to produce the bio-reagent, converting the bio-reagent to a reducing gas, and separating and recovering hydrogen from the reducing gas. A reducing gas composition for reducing metal oxides is provided that includes renewable hydrogen by hydrogen isotope analysis. The reacted bio-reagent can also be recovered as an activated carbon product. Many variations are disclosed.

Description

[Technical Field]

[0001] (Cross-reference of related applications) This application claims the interests of U.S. Provisional Patent Application No. 63 / 116,403, filed on 20 November 2020, and U.S. Provisional Patent Application No. 63 / 130,460, filed on 24 December 2020, each of which is incorporated herein by reference in whole.

[0002] (Field of Invention) This disclosure relates to processes, systems, and apparatus for processing metal ores to produce metals using carbon-containing reagents, as well as processes, systems, and apparatus for hydrogen production and activated carbon production from carbon-containing reagents. [Background technology]

[0003] Carbonaceous reagents are traditionally produced from fossil fuels. Carbonaceous materials include fossil resources such as natural gas, petroleum, coal, and lignite, or renewable resources such as lignocellulosic biomass and various carbon-enriched wastes. Converting renewable resources to carbonaceous reagents presents technical and economic challenges arising from raw material volatility, operational difficulties, and capital intensities. The increasing economic, environmental, and social costs associated with fossil resources are making renewable resources an attractive alternative to fossil resources in the production of carbonaceous reagents.

[0004] Historically, the slow pyrolysis of wood has been carried out in large piles in simple batch processes without emission control. Traditional charcoal production techniques are not only energy inefficient but also highly polluting. Scaling up such processes for the continuous commercial production of high-quality carbon while managing energy balance and controlling emissions presents economic and practical challenges. [Overview of the project]

[0005] A process is disclosed herein. In the process disclosed herein, the process is To provide biomass raw materials, The process involves thermally decomposing biomass raw materials to produce bioreagents containing carbon and thermal decomposition off-gases. The process involves reacting a bioreagent with a selected reactant to generate a reducing gas, This may include chemically reducing a selected metal oxide in the presence of a reducing gas to produce a reduced form of the selected metal oxide.

[0006] The pyrolysis off-gas can be oxidized, thereby generating heat. In some embodiments, the process may further include recovering the bioreagents continuously or periodically during the reaction, or finally after the reaction, thereby producing recovered bioreagents, which are activated carbon.

[0007] Pyrolysis can be carried out at temperatures ranging from approximately 250°C to approximately 1250°C or any number within that range, or at temperatures ranging from approximately 300°C to approximately 700°C or any number within that range. Pyrolysis can also be carried out for a duration ranging from approximately 10 seconds to approximately 24 hours or any number within that range.

[0008] The reaction can be carried out at a reaction temperature in the range of approximately 300°C to approximately 1200°C or any number within that range, for example, in the range of approximately 400°C to approximately 1000°C or any number within that range. The reaction can be carried out for a reaction time in the range of approximately 1 second to approximately 1 hour or any number within that range.

[0009] Chemical reduction can be carried out at a reduction temperature in the range of approximately 500°C to approximately 2000°C or any number within that range, for example, in the range of approximately 700°C to approximately 1800°C or any number within that range. Chemical reduction can be carried out for a reduction time in the range of approximately 30 minutes to approximately 48 hours or any number within that range.

[0010] In some embodiments, the biomass raw materials include softwood chips, hardwood chips, timber harvest residues, tree branches, tree stumps, leaves, bark, sawdust, corn, corn stalks and leaves, wheat, wheat straw, rice, rice straw, sugarcane, sugarcane bagasse, sugarcane straw, energy sugarcane, sugar beet, sugar beet pulp, sunflower, sorghum, canola, algae, Japanese pampas grass, alfalfa, switchgrass, fruits, and more fruits. This may include fruit shells, fruit stems, fruit peels, fruit seeds, vegetables, vegetable shells, vegetable stems, vegetable peels, vegetable seeds, grape pomace, tonsil shells, pecan shells, coconut shells, coffee grounds, food waste, commercial waste, grass pellets, hay pellets, wood pellets, cardboard, paper, paper pulp, paper packaging, paper trimmings, food packaging, construction or demolition waste, railway ties, lignin, animal manure, municipal solid waste, municipal sewage, or a combination thereof.

[0011] Bioreagents may contain any number of carbon atoms in the range of approximately 50, 55, 60, 65, 70, 75, 80, 85, 90, or 95% by weight, or any number in between. Such carbon is total carbon, which is the sum of fixed carbon and volatile carbon. Bioreagents may contain any number of fixed carbon atoms in the range of approximately 50, 55, 60, 65, 70, 75, 80, 85, 90, or 95% by weight, or any number in between.

[0012] The selected metal oxide may be iron oxide, copper oxide, nickel oxide, magnesium oxide, manganese oxide, aluminum oxide, tin oxide, zinc oxide, cobalt oxide, chromium oxide, tungsten oxide, molybdenum oxide, or a combination or derivative thereof. The selected metal oxide may be iron ore, and the iron ore may be hematite, magnetite, limonite, taconite, or a combination or derivative thereof.

[0013] The reduced form of the selected metal oxide may be a completely reduced metal. The reduced form of the selected metal oxide may be a second metal oxide having a lower oxidation state than the selected metal oxide. A mixture of a completely reduced metal and a second metal oxide can also be produced from the starting metal oxide.

[0014] In some embodiments, the process further includes oxidizing the pyrolysis off-gas to generate heat, which is used for heating in the pyrolysis. Alternatively or additionally, heat can be used for heating in the reaction. Alternatively or additionally, heat can be used for heating in the chemical reduction.

[0015] In some embodiments, the reducing gas contains hydrogen in the range of about 10 mol% to about 25 mol%, or any number in between. In certain embodiments, the reducing gas contains at least 25 mol% hydrogen.

[0016] In some embodiments, the reducing gas contains carbon monoxide in the range of about 10 mol% to about 25 mol%, or any number in between. In certain embodiments, the reducing gas contains at least 25 mol% carbon monoxide.

[0017] In some embodiments, the volatile carbon in the generated bioreagent is directed towards a reducing gas in the range of about 50% to about 90% by weight or any number in between. In some embodiments, essentially all of the volatile carbon in the generated bioreagent is directed towards a reducing gas.

[0018] The process may further include the hydrogen content of the reducing gas using a water-gas shift reaction. In some embodiments, whether or not a water-gas shift is performed, the process may further include separating hydrogen from the reducing gas and recovering the hydrogen. The hydrogen can be separated from the reducing gas using separation techniques. In some embodiments, the separation technique may include pressure swing adsorption, molecular sieve membrane separation, or cryogenic distillation.

[0019] In some embodiments, the selected reactant in reacting the bioreagent is water. In other embodiments, the selected reactant in the reaction is oxygen, which is present in air, pure oxygen, concentrated oxygen, ozone, or a combination thereof. In some embodiments, the selected reactant in the reaction is a combination of water (e.g., water vapor) and oxygen, or includes both.

[0020] In some embodiments, the reaction utilizes a fixed-bed reactor or a rotary kiln. In some embodiments, the reaction utilizes a fluidized-bed reactor.

[0021] The pyrolysis off-gas can be partially oxidized, thereby generating additional reducing gas and heat. In some embodiments, chemical reduction further includes chemically reducing a selected metal oxide in the presence of the additional reducing gas. When the pyrolysis off-gas is converted into an additional reducing gas, the additional reducing gas may include any number of hydrogen atoms in the range of about 20 mol% to about 40 mol% or between. The additional reducing gas may include any number of carbon monoxide atoms in the range of about 20 mol% to about 40 mol% or between.

[0022] In some embodiments, the process further includes recovering the reduced form of the selected metal oxide.

[0023] The process can be jointly installed in, for example, metal oxide mines, or metal oxide processing plants such as steel mills, taconite plants, or direct iron reduction plants.

[0024] In some embodiments, chemical reduction is carried out inside the metal ore furnace. In some embodiments, chemical reduction is carried out upstream of the metal ore furnace. The metal ore furnace may be a blast furnace, direct reduction metal furnace, top gas recirculation blast furnace, shaft furnace, reverberatory furnace, crucible furnace, silenced furnace, retort furnace, flash furnace, Tecnored furnace, Ausmelt furnace, ISASMELT furnace, paddle furnace, bogie hearth furnace, continuous chain furnace, pusher furnace, rotary hearth furnace, walking beam furnace, electric arc furnace, induction furnace, basic oxygen furnace, paddle furnace, Bessemer furnace, or a combination thereof.

[0025] In some embodiments, the thermal decomposition and chemical reduction of the biomass raw material are carried out in the same location. In certain embodiments, all process steps are carried out in a single location.

[0026] If activated carbon is the desired product, the process may further include recovering the bioreagent continuously or periodically during or after the reaction to produce the recovered bioreagent, which is activated carbon. In some embodiments, about 1% to about 99% by weight of the bioreagent produced by pyrolysis, or any number in that range, for example, at least about 10% by weight, at least about 50% by weight, or at least about 90% by weight, is recovered as activated carbon. In some embodiments, essentially all of the bioreagent produced in pyrolysis is recovered as activated carbon. In some embodiments, about 50% to about 99% by weight of the fixed carbon in the bioreagent produced in pyrolysis, or any number in that range, is recovered as activated carbon. In some embodiments, essentially all of the fixed carbon in the bioreagent produced in pyrolysis is recovered as activated carbon.

[0027] Activated carbon can be characterized by an iodine value in the range of approximately 500 to approximately 2000 or any number in between. Activated carbon can be characterized by an iodine value of at least approximately 750, at least approximately 1000, at least approximately 1500, or at least approximately 2000.

[0028] Activated carbon is activated carbon14 C / 12 It can be characterized by a renewable carbon content in the range of approximately 90% to approximately 100% or any number in between, determined from the measurement of the 1C isotope ratio. In some embodiments, activated carbon is 14 C / 12 It can be characterized as a fully renewable activated carbon, as determined by the measurement of its 1C isotope ratio.

[0029] Systems are also disclosed in this specification. The systems disclosed in this specification are A first reactor configured to thermally decompose a biomass raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas, A second reactor configured to react a bioreagent with a selected reactant to generate a reducing gas, The system may include a third reactor configured to chemically reduce a selected metal oxide in the presence of a reducing gas to produce a reduced form of the selected metal oxide.

[0030] In some embodiments, the second reactor is configured to remove activated carbon from the second reactor continuously, periodically, or eventually.

[0031] In some embodiments, the system further comprises one or more heating units that are in thermal communication with a first reactor, a second reactor, or a third reactor, the one or more heating units being configured to generate heat by oxidizing the pyrolysis off-gas.

[0032] In some embodiments, the first reactor is configured to operate at a thermal decomposition temperature in the range of about 250°C to about 1250°C or any number in that range, for example, in the range of about 300°C to about 700°C or any number in that range. The first reactor can be configured to operate at a thermal decomposition time in the range of about 10 seconds to about 24 hours or any number in that range.

[0033] In some embodiments, the second reactor is configured to operate at a reaction temperature in the range of about 300°C to about 1200°C or any number in that range, for example, in the range of about 400°C to about 1000°C or any number in that range. The second reactor can be configured to operate at a reaction time in the range of about 1 second to about 1 hour or any number in that range.

[0034] In some embodiments, the third reactor is configured to operate at a reduction temperature in the range of about 500°C to about 2000°C or any number in that range, for example, in the range of about 700°C to about 1800°C or any number in that range. The third reactor can be configured to operate at a reduction time in the range of about 30 minutes to about 48 hours or any number in that range.

[0035] The first reactor processes biomass raw materials, such as softwood chips, hardwood chips, timber harvest residues, tree branches, tree stumps, leaves, bark, sawdust, corn, corn stalks and leaves, wheat, wheat straw, rice, rice straw, sugarcane, sugarcane bagasse, sugarcane straw, energy sugarcane, sugar beets, sugar beet pulp, sunflowers, sorghum, canola, algae, pampas grass, alfalfa, switchgrass, fruits, fruit shells, and fruit stems. It can be configured to process fruit peels, fruit seeds, vegetables, vegetable shells, vegetable stems, vegetable peels, vegetable seeds, grape pomace, tonsil shells, pecan shells, coconut shells, coffee grounds, food waste, commercial waste, grass pellets, hay pellets, wood pellets, cardboard, paper, paper pulp, paper packaging, paper trimmings, food packaging, construction or demolition waste, railway ties, lignin, animal manure, municipal solid waste, municipal sewage, or a combination thereof.

[0036] A third reactor may be configured to reduce metal oxides, such as iron oxide, copper oxide, nickel oxide, magnesium oxide, manganese oxide, aluminum oxide, tin oxide, zinc oxide, cobalt oxide, chromium oxide, tungsten oxide, molybdenum oxide, or combinations thereof. The metal oxide may be a metal ore, such as hematite, magnetite, limonite, taconite, or combinations thereof. The reduced form of the selected metal oxide may be a second metal oxide having a lower oxidation state than the completely reduced metal or the selected metal oxide.

[0037] In some embodiments, there is a heating unit that has thermal communication with a first reactor. In some embodiments, there is a heating unit that has thermal communication with a second reactor. In some embodiments, there is a heating unit that has thermal communication with a third reactor. There may be separate heating units that have thermal communication with each reactor, or there may be one or more integrated heating units that have thermal communication with multiple reactors.

[0038] In some embodiments, the second reactor is configured to increase the hydrogen content of the reducing gas using a water-gas shift reaction.

[0039] In some embodiments, the system further comprises an additional reactor in fluid communication with a second reactor, the additional reactor configured to increase the hydrogen content of the reducing gas via a water-gas shift reaction.

[0040] In some embodiments, the system further comprises a separation unit configured to separate hydrogen from the reducing gas. The separation unit can be selected from, for example, a pressure swing adsorption unit, a molecular sieve membrane, or a cryogenic distillation unit.

[0041] The second reactor may be a fixed-bed reactor, a fluidized-bed reactor, a rotary kiln, or another type of reactor.

[0042] In some embodiments, the system further comprises an off-gas reactor configured to partially or completely oxidize the pyrolysis off-gas to produce an additional reducing gas. The off-gas reactor can be in fluid communication with a third reactor.

[0043] In some embodiments, a second reactor is further configured to receive the pyrolysis off-gas and convert it into an additional reducing gas.

[0044] In some embodiments, there is an outlet from a third reactor configured to recover the reduced form of the selected metal oxide.

[0045] In some embodiments, the system can be jointly installed in a metal oxide mine. The system can also be jointly installed in a metal oxide processing plant such as a steel mill, taconite plant, or direct iron reduction plant.

[0046] In some embodiments, the third reactor is a metal ore furnace. In some embodiments, the third reactor is upstream of the metal ore furnace. The metal ore furnace can be selected from blast furnaces, direct reducing metal furnaces, top gas recirculation blast furnaces, shaft furnaces, reverberatory furnaces, crucible furnaces, silenced furnaces, retort furnaces, flash furnaces, Tecnored furnaces, Ausmelt furnaces, ISASMELT furnaces, paddle furnaces, bogie hearth furnaces, continuous chain furnaces, pusher furnaces, rotary hearth furnaces, walking beam furnaces, electric arc furnaces, induction furnaces, basic oxygen furnaces, paddle furnaces, Bessemer furnaces, or combinations thereof.

[0047] In some embodiments, the first and third reactors are installed together in the same location. In some embodiments, the system as a whole is located in a single location.

[0048] The second reactor may be configured to continuously or periodically remove activated carbon from the second reactor. Alternatively or additionally, the second reactor may be configured to eventually remove activated carbon from the second reactor (at the end of the operating period). Activated carbon can be characterized by an iodine value of at least about 500. Activated carbon is activated carbon 14 C / 12 It can be characterized as a fully renewable activated carbon, as determined by the measurement of its 1C isotope ratio.

[0049] This specification also discloses metal products. The metal products are, To provide biomass raw materials, The process involves thermally decomposing biomass raw materials to produce bioreagents containing carbon and thermal decomposition off-gases. The process involves reacting a biological reagent with a selected reactant to generate a reducing gas, In the presence of a reducing gas, a selected metal oxide is chemically reduced, thereby producing a reduced form of the selected metal oxide. The metal product, including the reduced form of the selected metal oxide, can be produced by a process that includes recovering the metal product.

[0050] In some embodiments, the process further includes oxidizing the pyrolysis off-gas, thereby generating heat.

[0051] In some embodiments, the process further includes recovering the bioreagents continuously or periodically during or after the reaction, thereby producing recovered bioreagents which are activated carbon.

[0052] In some embodiments, the chemical reduction is carried out at a reduction temperature in the range of about 500°C to about 2000°C or any number in that range, for example, in the range of about 700°C to about 1800°C or any number in that range. The chemical reduction can be carried out for a reduction time in the range of about 30 minutes to about 48 hours or any number in that range.

[0053] The selected metal oxides may be iron oxide, copper oxide, nickel oxide, magnesium oxide, manganese oxide, aluminum oxide, tin oxide, zinc oxide, cobalt oxide, chromium oxide, tungsten oxide, molybdenum oxide, or a combination thereof. Exemplary metal oxides are iron ores, such as hematite, magnetite, limonite, taconite, or a combination thereof. The reduced form may be a second metal oxide having a lower oxidation state than the fully reduced metal or the selected metal oxide.

[0054] The reactants selected in the reaction may be water, oxygen, or a mixture thereof. Oxygen may be present in air, pure oxygen, concentrated oxygen, ozone, or a combination thereof.

[0055] In some embodiments, the reducing gas contains hydrogen in the range of about 10 mol% to at least about 25 mol%, or any number in between. In some embodiments, the reducing gas contains carbon monoxide in the range of about 10 mol%, or at least about 25 mol%, or any number in between.

[0056] In some embodiments, the metal product is produced by a process that further includes increasing the hydrogen content of the reducing gas using a water-gas shift reaction.

[0057] In some embodiments, the pyrolysis off-gas is partially or completely oxidized, thereby generating additional reducing gas and heat. In some embodiments, the additional reducing gas can be used in chemical reduction to chemically reduce a selected metal oxide.

[0058] In various embodiments, the metallic product includes iron, copper, nickel, magnesium, manganese, aluminum, tin, zinc, cobalt, chromium, tungsten, molybdenum, or combinations thereof.

[0059] Renewable hydrogen products are also disclosed herein. Renewable hydrogen products are, To provide biomass raw materials, pyrolyzing a biomass feedstock, thereby producing a carbon-containing bioreagent and pyrolysis off-gas, reacting the bioreagent with a selected reactant, thereby producing a reducing gas, separating hydrogen from the reducing gas, recovering a renewable hydrogen product comprising hydrogen; and can be produced by a process comprising the foregoing.

[0060] In some embodiments, the process further comprises oxidizing the pyrolysis off-gas, thereby generating heat.

[0061] In some embodiments, separating hydrogen from the reducing gas comprises separating hydrogen using a separation technique such as pressure swing adsorption, molecular sieve membrane separation, or cryogenic distillation.

[0062] In some embodiments, the process further comprises recovering the bioreagent during or after the reaction, continuously or periodically, thereby producing recovered bioreagent that is activated carbon.

[0063] The hydrogen can be characterized as renewable hydrogen in the range of from about 50% to at least about 99%, or any number therebetween, in accordance with hydrogen isotope 2 H / 1 H analysis. In some hydrogen products, the hydrogen is characterized as at least 90% renewable hydrogen or at least 95% renewable hydrogen. In some hydrogen products, the hydrogen is characterized as being essentially completely renewable hydrogen.

[0064] Contained in the reducing gas, the 2 H / 1 H isotope ratio of hydrogen separated from the reducing gas can be in the range of from about 0.0002 to about 0.001, or any number therebetween, for example, in the range of from about 0.0002 to about 0.005, or any number therebetween.

[0065] In some embodiments, hydrogen is characterized as fully renewable hydrogen, and any residual carbon contained in the hydrogen product is 14 C / 12 It is essentially a completely renewable form of carbon, determined by the measurement of its 1C isotope ratio.

[0066] The reactants selected in the reaction may be water, oxygen, or a mixture thereof. Oxygen may be present in air, pure oxygen, concentrated oxygen, ozone, or a combination thereof.

[0067] In some embodiments, the reducing gas comprises hydrogen in a range of about 10 mol% or at least about 25 mol% or any number of hydrogen atoms. In some embodiments, the reducing gas comprises carbon monoxide in a range of at least about 10 mol% or at least about 25 mol% or any number of carbon monoxide atoms.

[0068] In some embodiments, the hydrogen product is produced by a process that further includes increasing the hydrogen content of the reducing gas using a water-gas shift reaction.

[0069] In some embodiments, the pyrolysis off-gas is partially or completely oxidized, thereby generating additional reducing gas and heat.

[0070] In some embodiments, hydrogen is separated using pressure swing adsorption, molecular sieve membrane separation, cryogenic distillation, or a combination thereof.

[0071] The hydrogen product may contain hydrogen in the range of about 50 mol% to about 90 mol%, or any number in between. In some embodiments, the hydrogen product contains at least 90 mol% hydrogen.

[0072] In some embodiments, the hydrogen product contains at most about 1 mol% nitrogen, or is substantially nitrogen-free.

[0073] A reducing gas composition that can be used to reduce metal oxides is further disclosed herein, the reducing gas composition comprising at least about 25 mol% hydrogen, wherein the hydrogen is an isotope. 2 H / 1 According to H analysis, at least approximately 50% of the hydrogen is renewable.

[0074] In some embodiments, the reducing gas composition includes a range of about 50 mol% to at least about 90 mol% or any number of hydrogens in between, for example, a range of about 75 mol% or at least about 90 mol% or any number of hydrogens.

[0075] In some embodiments, hydrogen is a hydrogen isotope 2 H / 1 According to H analysis, it is characterized as renewable hydrogen in the range of about 80% to at least about 99%, or any number in between. In certain embodiments, hydrogen is a hydrogen isotope. 2 H / 1 It is characterized as at least about 90% renewable hydrogen according to 1H analysis. In certain embodiments, hydrogen is a hydrogen isotope. 2 H / 1 According to 1H analysis, it is characterized as essentially completely renewable hydrogen.

[0076] In some embodiments, the reducing gas composition may further include a carbon-containing gas comprising CO, CO2, or CH4, or the reducing gas composition may further include a carbon-containing gas essentially derived from CO, CO2, or CH4. In some embodiments, the carbon-containing gas is 14 C / 12 Determined from the measurement of the 1C isotope ratio, it is in the range of about 50% to at least about 99% or any number in between, such as at least about 90% renewable or essentially completely renewable. If the reducing gas composition contains a carbon-containing gas, hydrogen is an isotope of hydrogen. 2 H / 1 According to H analysis, it can be characterized as at least 90% renewable hydrogen, or essentially completely renewable hydrogen.

[0077] In some embodiments, the reducing gas composition further comprises carbon monoxide, where carbon monoxide is 14 C / 12 Renewable to any number in the range of about 50% to about 99%, or any number in between, such as at least 90% renewable or essentially completely renewable, as determined by the measurement of the 1C isotope ratio. In some embodiments, if the reducing gas composition further contains carbon monoxide, hydrogen is a hydrogen isotope. 2 H / 1 According to 1H analysis, it is characterized as consisting of at least 90% renewable hydrogen, or essentially entirely renewable hydrogen. In some reducing gas compositions, the molar ratio of hydrogen to carbon monoxide is at least 2.

[0078] In some embodiments, the reducing gas composition contains at most about 1 mol% of N2, at most about 0.5 mol% of N2, at most about 0.1 mol% of N2, or is essentially N2-free.

[0079] Furthermore, activated carbon products are disclosed herein. The activated carbon products are To provide biomass raw materials, The process involves thermally decomposing biomass raw materials to produce bioreagents containing carbon and thermal decomposition off-gases. The process involves reacting a biological reagent with a selected reactant to generate a reducing gas, It can be produced by a process that includes recovering a bioreagent during or after a reaction, either continuously or periodically, wherein the recovered bioreagent is activated carbon.

[0080] In some embodiments, the activated carbon product is produced by a process that further includes oxidizing the pyrolysis off-gas, thereby generating heat.

[0081] In some embodiments, the activated carbon product is produced by a process that further includes chemically reducing a selected metal oxide in the presence of a reducing gas from the reaction, thereby generating a reduced form of the selected metal oxide.

[0082] In some embodiments, the pyrolysis is carried out at a pyrolysis temperature in the range of about 250°C to about 1250°C or any number in that range, for example, in the range of about 300°C to about 700°C or any number in that range. The pyrolysis can be carried out for a pyrolysis time in the range of about 10 seconds to about 24 hours or any number in that range.

[0083] In some embodiments, the reaction is carried out at a reaction temperature in the range of about 300°C to about 1200°C or any number in that range, for example, in the range of about 400°C to about 1000°C or any number in that range. The reaction can be carried out for a reaction time in the range of about 1 second to about 1 hour or any number in that range.

[0084] In some embodiments, the bioreagent produced in the pyrolysis contains any number of carbon atoms in the range of about 50% by weight or at least about 99% by weight, for example, any number of carbon atoms in the range of about 50% by weight or at least about 75% by weight. This bioreagent may contain any number of fixed carbon atoms in the range of about 50% by weight or at least about 99% by weight, for example, any number of fixed carbon atoms in the range of about 50% by weight or at least about 75% by weight.

[0085] In some embodiments, the reducing gas comprises hydrogen ranging from about 10 mol% or at least about 25 mol% or any number of hydrogens in between.

[0086] In some embodiments, the reducing gas comprises carbon monoxide ranging from about 10 mol% or at least about 25 mol% or any number in between.

[0087] In some embodiments, the activated carbon product is produced by a process that further includes increasing the hydrogen content of the reducing gas via a water-gas shift reaction.

[0088] In some embodiments, the selected reactants in the reaction are water, oxygen, or a mixture thereof. Oxygen may be present in air, pure oxygen, concentrated oxygen, ozone, or a combination thereof.

[0089] In some embodiments, about 10% to 99% by weight of the bioreagent produced by thermal decomposition, or any number in between, for example, from about 50% by weight or at least about 90% by weight, or any number in between, is recovered as activated carbon.

[0090] In some embodiments, approximately 50% to at least 99% by weight of the fixed carbon in the generated bioreagent, or any number in between, or essentially all of it, is recovered as activated carbon.

[0091] Activated carbon can be characterized by an iodine value in the range of about 500 to about 2000 or any number in between. In some embodiments, activated carbon is characterized by an iodine value of at least about 1000, at least about 1500, or at least about 2000.

[0092] Activated carbon is activated carbon 14 C / 12 It can be characterized by a renewable carbon content of at least 90%, determined from the measurement of the 1C isotope ratio. In certain embodiments, activated carbon is activated carbon 14 C / 12 It is characterized as an essentially completely renewable activated carbon, as determined by the measurement of its 1C isotope ratio. [Brief explanation of the drawing]

[0093] [Figure 1] In some embodiments, this is a simplified block flow diagram of a process for converting biomass raw materials into a reducing gas composition that is optionally used to reduce metal oxides to metal products. Dotted lines indicate optional flows and units.

[0094] [Figure 2]In some embodiments, this is a simplified block flow diagram of a process for converting biomass raw materials into reducing gas compositions used to produce renewable hydrogen. Dotted lines indicate optional flows and units.

[0095] [Figure 3] In some embodiments, this is a simplified block flow diagram of a process for converting biomass raw materials into activated carbon and reducing gas compositions. Dotted lines indicate optional flows and units.

[0096] [Figure 4] In some embodiments, this is a simplified block flow diagram of a process for converting biomass raw materials into activated carbon and reducing gas compositions used to reduce metal oxides to metal products. Dotted lines indicate optional flows and units. [Modes for carrying out the invention]

[0097] This description will enable those skilled in the art to create and use the disclosed disclosure and will describe some embodiments, adaptations, modifications, substitutions, and uses of the disclosure. These and other embodiments, features, and advantages of the disclosure will become more apparent to those skilled in the art when viewed in conjunction with the accompanying drawings and the following detailed description of the disclosure.

[0098] For the purpose of enabling technical disclosure, various explanations, hypotheses, theories, speculations, and assumptions are disclosed. This disclosure does not rely on any of these to be actually true. None of the explanations, hypotheses, theories, speculations, or assumptions in this detailed explanation should be construed as limiting the scope of this disclosure in any way.

[0099] The headings provided herein are for convenience only and do not constitute an interpretation of the scope or meaning of the claimed embodiments.

[0100] Various conversion technologies exist for converting biomass raw materials into high-carbon materials. Pyrolysis is a process for thermally converting solid materials in the complete absence of an oxidizing agent (air or oxygen), or with a limited supply of an oxidizing agent such that oxidation does not occur to a noticeable degree. Depending on the process conditions and additives, biomass pyrolysis can be controlled to produce a wide range of gases, liquids, and solids. Lower process temperatures and longer vapor residence times are favorable for solid production. Higher temperatures and longer residence times increase the conversion of biomass to synthesis gas, while moderate temperatures and short vapor residence times are generally optimal for liquid production. There is a need for pyrolysis processes specifically aimed at optimizing the yield and quality of solid pyrolysis products as carbon reagents.

[0101] Metalworking is a globally vital industry. For example, regarding steel (iron alloys), the global steel market size is projected to reach US$1 trillion by 2025, according to *Steel Market Size, Share & Trends Analysis 2018-2025*, Grand View Research, Inc. (2017). The growing trend among contractors for sustainable, low-cost, and durable building materials is driving the demand for steel in industrial infrastructure and residential projects. In pre-designed metal structures with high structural integrity, steel plays an essential role in stability, design flexibility, and aesthetic appeal. Strict regulations promoting green and energy-efficient buildings are also contributing to the demand for steel, particularly in industrial structures.

[0102] Approximately 70% of all steel is made from pig iron produced by reducing iron oxide in a blast furnace using coke or coal before being reduced in an oxygen converter. The use of non-renewable coal or coal-derived coke releases non-renewable carbon dioxide into the atmosphere, in addition to depleting fossil resources.

[0103] Oxygenated iron ore is mined worldwide. Iron ore is extracted through a beneficiation process, where the iron fraction is crushed and concentrated, then rolled into pellets (with a binder), heated in a hardening furnace where coal is burned for heating, the pellets are solidified and transported to a blast furnace where coke is used to reduce the oxygenated ore back to metallic iron. The hardening and coking processes generate large amounts of CO2 and other pollutants.

[0104] Metalworking generates significant net CO2 emissions worldwide every year. One of the biggest drawbacks of conventional blast furnaces is the unavoidable CO2 production, as iron is reduced from iron oxide by carbon or carbon monoxide (CO). Steelmaking is one of the largest industrial contributors to CO2 emissions in the world today. There is a strong desire to make metalworking processes more environmentally friendly.

[0105] Hydrogen is used in a variety of industrial applications, including metal alloying, glassmaking, electronics processing (e.g., in deposition, cleaning, etching, and reduction), and power generation (e.g., for corrosion prevention in pipelines).

[0106] Hydrogen is used to process crude oil into refined fuels such as gasoline and diesel, or to remove contaminants such as sulfur from these fuels. The use of hydrogen in oil refineries has increased in recent years due to stricter regulations requiring lower sulfur in diesel fuel and the increasing consumption of lower-quality crude oil, which requires more hydrogen to refine. Refineries produce some by-product hydrogen from the catalytic reforming of naphtha, but this supply only meets a small fraction of their hydrogen needs. Approximately 80% of the hydrogen currently consumed worldwide by refineries is supplied by large-scale hydrogen plants that produce non-renewable hydrogen from natural gas or other hydrocarbon fuels.

[0107] The direct reduction of iron ore using hydrogen has the potential to develop into a significant industrial process in steelmaking. Conventional blast furnaces release large amounts of carbon dioxide. By replacing carbon or carbon monoxide with hydrogen to reduce metal oxides into metal products, the co-product shifts from carbon dioxide to water. The environmental benefits are even greater if the hydrogen used in the reduction of iron ore is renewable hydrogen.

[0108] definition As used herein, the singular forms “a,” “an,” and “the” include multiple referents unless the context clearly indicates otherwise. For example, at any point where a product is produced, the process can be controlled to produce two or more products, such that if “particulate carbon metal ore” is produced, “multiple particulate carbon metal ore” may be produced. This also applies to compositions containing a single component. For example, if a composition contains particulate carbon metal ore, the composition may contain multiple particulate carbon metal ore.

[0109] Unless otherwise indicated, all figures used in this specification and the claims, such as reaction conditions, stoichiometry, and component concentrations, should be understood in all cases to be modified by the term "approximately." Therefore, unless otherwise indicated, the numerical parameters described in the following specification and the appended claims are approximations that may vary depending on the specific analytical technique.

[0110] As used herein, the term “approximately” means ±20% of the indicated range, value, or structure unless otherwise indicated.

[0111] Where used herein, any concentration range, percentage range, ratio range, or integer range should be understood, unless otherwise indicated, to include any integer values ​​within the listed range and, where appropriate, fractions thereof (such as one-tenth and one-hundredth of an integer). Similarly, any range of numbers listed herein should be understood, unless otherwise indicated, to include any integers within the listed range.

[0112] As used herein, “a range from or between about X, Y, or Z” includes “at least X to at most (higher or longer than) Z.”

[0113] As used herein, “living” refers to materials (raw materials, products, or intermediates) containing elements such as carbon that are renewable on a timescale of months, years, or decades. Non-living materials may be non-renewable or renewable on a timescale of centuries, millennia, millions of years, or even longer geological timescales. For example, conventional fuel sources such as coal and petroleum are non-renewable and non-living. Living materials may essentially be derived from living sources. It will be understood by those skilled in the art that living materials as or derived from natural sources may contain trace amounts of non-living materials. Furthermore, the processes disclosed herein may be used with non-living materials, although the beneficial environmental impact may not be significant.

[0114] The three natural isotopes of carbon, 12 C, 13 C, and 14 C exists. 12 C and 13 C is stable and exists in a natural ratio of approximately 93:1. 14 C is produced by thermal neutrons from cosmic rays in the upper atmosphere, transported to Earth, and absorbed by living biological materials. Isotopeically, 14 C constitutes a negligible portion. However, it is radioactive with a half-life of 5,700 years, and therefore detectable radiometrically. Dead tissue, 14Since it does not absorb C, 14 The amount of C is one of the methods used for radiometric dating of biological materials.

[0115] Plants fix atmospheric carbon through photosynthesis. 14 It takes in C. Then, when an animal consumes a plant, or consumes another animal that consumes a plant, 14 They take in carbon into their bodies. Therefore, living plants and animals take in the same amount of carbon as CO2 in the atmosphere. 14 C vs 12 It has a C ratio. When an organism dies, it stops exchanging carbon with the atmosphere and therefore no longer produces new carbon. 14 It does not take in C. Next, radioactive decay occurs in living organisms. 14 It gradually depletes the amount of carbon. This effect is the basis of radiocarbon dating.

[0116] Fossil fuels such as coal are primarily made from plant material that accumulated millions of years ago. During this period, 14 It is equivalent to thousands of half-lives of C, so essentially all of the fossil fuels 14 C is decaying. Because fossil fuels were originally formed from living organisms, they affect the atmosphere. 13 Carbon is depleted. Therefore, carbon from fossil fuels is less beneficial compared to biocarbon. 13 C and 14 Both C components are depleted.

[0117] This difference between carbon isotopes from recently depleted organic materials, such as those from renewable resources, and carbon isotopes from fossil fuels such as coal, allows for the determination of the carbon source in a composition. Specifically, it determines whether the carbon in the composition originates from renewable resources or fossil fuels; in other words, whether renewable resources or fossil fuels were used in the production of the composition.

[0118] Biomass is a term used to describe biologically produced or biomaterials. Biomass refers to a mass of living organisms, including plants, animals, and microorganisms, or, from a biochemical standpoint, cellulose, lignin, sugars, fats, and proteins. Biomass includes both the above-ground and below-ground tissues of plants, such as leaves, twigs, branches, and trunks, as well as the roots of trees and the rhizomes of grasses. The chemical energy contained in biomass is derived from solar energy, using the natural process of photosynthesis. This is the process by which plants take in carbon dioxide and water from their surroundings and use energy from sunlight to convert them into sugars, starch, cellulose, hemicellulose, and lignin. Biomass is useful in that it is effectively stored solar energy. Furthermore, biomass is the only renewable carbon source.

[0119] As used herein, “combustion stoichiometric amount of oxygen” is the amount of oxygen that completely oxidizes carbon-containing or hydrogen-containing components to CO2 or H2O, respectively, without being in a stoichiometric excess, whether present in air, pure oxygen, or oxygen-enriched air. When the pyrolysis off-gas is intentionally oxidized to less than a stoichiometric amount for combustion, the oxygen used as the percentage of the combustion stoichiometric amount of oxygen may be at least about 10% to at most about 99%, at least about 25% to at most about 90%, or at least about 40% to at most about 80%. In various embodiments, this percentage is about, at least about, or at most about 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95%. These percentages are based on the molar basis of oxygen being in the O2 form.

[0120] As used herein, "comprising," which is synonymous with "including," "containing," or "characterized by," is comprehensive or open-ended and does not exclude additional unlisted elements or method steps. "Comprising" is a technical term used in claim language to indicate that a specified claim element is essential, but other claim elements may be added and still form components within the scope of this disclosure. "Comprising" further provides a basis for "consisting of" or "consisting essentially of." For example, if a formulation "contains X, Y, and Z," the formulation may consist of or essentially consist of X, Y, and Z.

[0121] As used herein, “consisting of” excludes any element, step, or component not specified. If the phrase “consisting of” appears in a section of the claim rather than immediately following the preamble, the phrase limits only the elements described in that section, and does not exclude other elements as a whole from the claim. As used herein, the phrase “essentially consisting of” limits the claim to any element or method step other than those specified, which does not substantially affect the basis of the claimed subject matter.

[0122] As used herein, “derivative” is a compound, molecule, or ion derived from another substance by a chemical reaction. The substance from which the derivative is derived is an additive. The derivative is also an additive.

[0123] As used herein, "high carbon," as in "high carbon bioreagent," indicates that the bioreagent has a high carbon content relative to the raw materials used to produce the high carbon bioreagent. A high carbon bioreagent may contain at least about half of its weight as carbon. For example, a high carbon bioreagent may contain any number of carbons in the range of 55 to 99% by weight or any number in between, for example, at least about 55, 60, 65, 70, 75, 80, 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% by weight of carbon.

[0124] As used herein, “high-carbon bioreagent” describes a material that can be produced by the disclosed processes and systems. Limitations regarding carbon content or any other concentration are not attributable by the term itself but only by reference to specific embodiments. For example, when raw materials containing a low carbon content are subjected to the disclosed process, the product is a high-carbon bioreagent with a relatively low carbon content (low purity carbon), although carbon is highly concentrated (high yield carbon) relative to the starting material, but nevertheless contains at most about 50% by weight of carbon.

[0125] As used herein, the terms “include,” “have,” and “comprise” are to be used synonymously, and these terms and their variations are intended to be construed as non-limiting.

[0126] As used herein, “metal ore” refers to a metal-containing material in which the desired metal exists not in a pure elemental form, but rather as a metal oxide, metal sulfide, metal nitride, metal carbide, metal boride, metal phosphide, or another form of metal.

[0127] The use of the word "or" in relation to a list of two or more items encompasses all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list. Furthermore, the phrase "at least one of A, B, and C, etc." is intended to be understood by convention by those skilled in the art (for example, "a system having at least one of A, B, and C" would, without limitation, include systems having only A, only B, only C, A and B together, A and C together, B and C together, or A, B and C together, etc.). Where a clause similar to “at least one of A, B, or C” is used, such a clause is generally intended to be understood by a person skilled in the art (for example, “a system having at least one of A, B, or C” would include, but is not limited to, systems having only A, only B, only C, A and B together, A and C together, B and C together, or A, B and C together, etc.).

[0128] As used herein, “pellets” are synonymous with “briquettes,” and the terms pellets, briquettes, pellets / briquettes, or similar terms may refer to aggregated material rather than loose powder. For convenience, the term “pellets” is used more commonly. The shape of pellets is not limited to spherical or nearly spherical. Pellet shapes may be spherical (circular or ball-shaped), cubic (square), octagonal, hexagonal, honeycomb / beehive-shaped, elliptical, egg-shaped, cylindrical, rod-shaped, bread-shaped, pillow-shaped, random, or a combination thereof.

[0129] As used herein, “pyrolysis” refers to the thermal decomposition of a carbonaceous material. In thermal decomposition, there is less oxygen present than is required for the complete combustion of the material, such as at most about 10%, 5%, 1%, 0.5%, 0.1%, or 0.01% of the oxygen (on a molar basis of O2) required for complete combustion. In some embodiments, thermal decomposition is carried out in the absence of oxygen.

[0130] As used herein, “reagent” refers to a material in its broadest sense. For example, a reagent may be a fuel, chemical, material, compound, additive, blend component, or solvent. A reagent does not necessarily have to be a chemical reagent that causes or participates in a chemical reaction. However, a reagent may be a chemical reactant that can be consumed in a reaction. A reagent may be a chemical catalyst for a particular reaction. A reagent may cause or participate in modifying the mechanical, physical, or hydrodynamic properties of a material to which the reagent may be added. For example, a reagent can be introduced into a metal to impart a particular strength property to the metal. A reagent may be a substance of sufficient purity (typically carbon purity in the current context) to be used for chemical analysis or physical testing.

[0131] As used herein, “renewable hydrogen” does not refer to hydrogen contained in a water (H2O) reactant that can be used to react with carbon or CO to form H2, regardless of its renewability. 2 H / 1 The 1H isotope ratio is determined by correlating it with the recyclability of the starting material. 2 H / 1 H isotope ratios correlate with the renewability of hydrogen. 2 H / 1 The 1H isotope ratio indicates a higher renewable hydrogen content.

[0132] As used herein, “total carbon” is the sum of fixed and unfixed carbon present in a volatile substance. In some embodiments, the weight percentages of components are on an absolute basis and are assumed unless otherwise specified. In other embodiments, the weight percentages of components are on an anhydrous and ashless basis.

[0133] As used herein, “zone” refers to a region of space within a single physical unit, a physically separated unit, or any combination thereof. With respect to a continuous reactor, zone boundaries may relate to structures such as the presence of flights within the reactor or separate heating elements for providing heat to separate zones. Alternatively or additionally, zone boundaries in a continuous reactor may relate to features such as separate temperatures, fluid flow patterns, solid flow patterns, or the degree of reaction. In a single-batch reactor, “zone” is an operating regime in time, rather than space. There are not necessarily abrupt transitions from one zone to another. For example, the boundary between a preheating zone and a pyrolysis zone may be somewhat arbitrary. Some amount of pyrolysis may occur in part of the preheating zone, and some amount of “preheating” may continue in the pyrolysis zone. The temperature profile within the reactor, including the zone boundaries within the reactor, is typically continuous.

[0134] Processes and Systems Disclosed herein are improved processes and systems for reducing metal ores and for producing renewable hydrogen for other industrial applications.

[0135] Some embodiments are based on processes and systems for generating renewable reducing gases from biomass. These reducing gases can be used to reduce metal oxides or to generate renewable hydrogen.

[0136] In some embodiments, a first reactor is supplied with wood or another biomass source. The first reactor is a pyrolysis reactor configured to produce carbon and pyrolysis off-gas (also called biogas) from the raw materials. A second reactor is configured to receive carbon and reactants such as water or oxygen to carry out a reaction that forms a reducing gas from carbon. The reducing gas may include hydrogen and carbon monoxide. Optionally, a water-gas shift reaction is used to convert H2O to H2 (and CO to CO2) to increase the hydrogen content of the reducing gas. The reducing gas can be sent to a separation unit to recover the hydrogen-concentrated product. Alternatively or additionally, a third reactor may be configured to directly or indirectly receive (a) a reducing gas from the second reactor and (b) a metal oxide, which is operated under reducing conditions effective in converting the metal oxide to a reduced metal, and the reducing off-gas may include at least H2O, and the reducing off-gas may further include CO and CO2. The pyrolysis off-gas is oxidized, thereby generating heat that can be used to heat the first, second, or third reactor. The process and system can be deployed on-site at metal oxide mines, such as iron ore mines, or at metal oxide processing plants, such as taconite processing plants. The process and system reduces or eliminates pollution and costs for the hardening, pelletizing, and transport of iron ore (or other metal oxides). The process and system also reduces pollution and costs for coking coal used to produce metallurgical coke, or for transporting petroleum coke to blast furnaces. The process and system can also improve the metallic purity of the final product.

[0137] Modifications of this disclosure will be described with reference to the attached drawings (Figures 1, 2, 3, and 4), which are not intended to limit the scope of the invention but rather illustrate various embodiments.

[0138] Figure 1 is a simplified block flow diagram of a process and system for converting biomass raw materials into a reducing gas composition that is optionally used to reduce metal oxides to metal products, in some embodiments. Dotted lines indicate optional flows and units.

[0139] Figure 2 is a simplified block flow diagram of a process and system for converting biomass raw materials into reducing gas compositions used to produce renewable hydrogen, in some embodiments. Dotted lines indicate optional flows and units.

[0140] Figure 3 is a simplified block flow diagram of a process for converting biomass raw materials into activated carbon and reducing gas compositions in several embodiments. Dotted lines indicate optional flows and units.

[0141] Figure 4 is a simplified block flow diagram of a process for converting biomass raw materials into activated carbon and an in-situ reducing gas composition for reducing metal oxides to metal products, in several embodiments. Dotted lines indicate optional flows and units. The zone of the second reactor can be switched so that the carbon bed is physically above the metal oxide bed.

[0142] Some variant forms are, (a) To provide biomass raw materials, (b) The process of thermally decomposing biomass raw materials to produce bioreagents containing carbon and thermal decomposition off-gases, (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting a bioreagent with a selected reactant to generate a reducing gas, (e) optionally, a process is provided which includes chemically reducing a selected metal oxide in the presence of a reducing gas from step (d) to produce a reduced form of the selected metal oxide.

[0143] Some embodiments include, (a) To provide biomass raw materials, (b) The process of thermally decomposing biomass raw materials to produce bioreagents containing carbon and thermal decomposition off-gases, (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting a bioreagent with a selected reactant to generate a reducing gas, (e) Optionally, chemically reduce the selected metal oxide in the presence of the reducing gas from step (d) to produce the reduced form of the selected metal oxide. (f) A process is provided which optionally recovers the bioreagent continuously or periodically during step (d) or finally after step (d) (e.g., by removing carbon from the reactor in a batch manner), wherein the recovered bioreagent is activated carbon.

[0144] In some embodiments, step (b) is performed at a pyrolysis temperature selected from about 250°C to about 1250°C, for example, about 300°C to about 700°C, specifically as provided in the above summary. In these or other embodiments, step (b) is performed over a pyrolysis time selected from about 10 seconds to about 24 hours or 48 hours, specifically as provided in the above summary. Generally, lower pyrolysis temperatures require longer pyrolysis times, while higher pyrolysis temperatures allow for shorter pyrolysis times.

[0145] In some embodiments, step (d) is carried out at a reaction temperature selected from about 300°C to about 1200°C, for example, about 400°C to about 1000°C, specifically referring to those provided in the summary above. In these or other embodiments, step (d) is carried out over a reaction time selected from about 1 second to about 1 hour, specifically referring to those provided in the summary above. Generally, the reaction temperature for forming the reducing gas is selected to achieve the desired chemical reaction. The reaction time can be determined by the mass and heat transfer to and from the reacting solids (smaller particles can be converted in shorter reaction times).

[0146] In some embodiments, step (e) is carried out at a reduction temperature selected from about 500°C to about 2000°C, for example, from about 700°C to about 1800°C, specifically referring to those provided in the above summary. In these or other embodiments, step (e) is carried out over a reduction time selected from about 30 minutes to about 48 hours, specifically referring to those provided in the above summary. Generally, lower reduction temperatures require longer reduction times, while higher reduction temperatures allow for shorter reduction times.

[0147] In some embodiments, the biomass raw materials include softwood chips, hardwood chips, timber harvest residues, tree branches, tree stumps, leaves, bark, sawdust, corn, corn stalks and leaves, wheat, wheat straw, rice, rice straw, sugarcane, sugarcane bagasse, sugarcane straw, energy sugarcane, sugar beet, sugar beet pulp, sunflower, sorghum, canola, algae, Japanese pampas grass, alfalfa, switchgrass, fruits, and berries. This includes shells, fruit stems, fruit peels, fruit seeds, vegetables, vegetable shells, vegetable stems, vegetable peels, vegetable seeds, grape pomace, tonsil shells, pecan shells, coconut shells, coffee grounds, food waste, commercial waste, grass pellets, hay pellets, wood pellets, cardboard, paper, paper pulp, paper packaging, paper trimmings, food packaging, construction or demolition waste, railway ties, lignin, animal manure, municipal solid waste, municipal sewage, or combinations thereof. Biomass raw materials may contain carbon, hydrogen, and oxygen.

[0148] The bioreagent produced in step (b) may contain at least about 50% by weight, at least about 75% by weight, or at least about 90% by weight of carbon (also known as total carbon), specifically as provided in the summary above. In various embodiments, the bioreagent may contain at least about 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 99% by weight of carbon, specifically as provided in the summary above. Total carbon is the sum of fixed and unfixed carbon present in the volatile substance. In some embodiments, the weight percentages of components are on an absolute basis and are assumed unless otherwise specified. In other embodiments, the weight percentages of components are on an anhydrous and ashless basis.

[0149] The bioreagent produced in step (b) may contain at least about 50% by weight, at least about 75% by weight, or at least about 90% by weight of fixed carbon, specifically as provided in the summary above. In various embodiments, the bioreagent may contain at least about 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 99% by weight of fixed carbon, specifically as provided in the summary above.

[0150] The carbon contained in the bioreagent may be fixed carbon of at least about 50% by weight, at least about 75% by weight, or at least about 90% by weight, specifically as provided in the summary above, with the remainder being volatile carbon. In various embodiments, the carbon may contain about, at least about, or at most about 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 99, or 100% by weight of fixed carbon, specifically as provided in the summary above.

[0151] The conditions in step (b) can vary considerably depending on the desired composition of the bioreagent and pyrolysis off-gas, the starting materials, the type of metal oxide, the reactor configuration, and other factors (described in detail later). The pyrolysis temperature is an important parameter and should be controlled. Generally speaking, higher pyrolysis temperatures, e.g., about 600°C to about 850°C, produce more hydrogen in the pyrolysis off-gas and leave less hydrogen in the bioreagent. This is advantageous in embodiments where hydrogen in the off-gas is utilized for the reduction of the metal oxide. On the other hand, lower pyrolysis temperatures, e.g., about 400°C to about 600°C, leave more hydrogen in the bioreagent and therefore less hydrogen in the off-gas. This may be advantageous in embodiments such as the injection of biocarbon into a metal reduction furnace, where hydrogen in the bioreagent is utilized for the reduction of the metal oxide. In either scenario, hydrogen can be utilized for the reduction of the metal oxide, which is desirable because it avoids direct CO2 production and thereby improves the environmental footprint by reducing carbon intensity.

[0152] In some embodiments, the metal oxide is included in metal ores, such as iron ore, copper ore, nickel ore, magnesium ore, manganese ore, aluminum ore, tin ore, zinc ore, cobalt ore, chromium ore, tungsten ore, molybdenum ore, or a combination thereof. In certain embodiments, the metal ore is an iron ore selected from, for example, hematite, magnetite, limonite, taconite, or a combination thereof.

[0153] Metal oxides can be present in beneficiated metal ore, in other words, in metal ore processed in one or more beneficiation units. Metal oxides can also be present in particulate form, such as in the form of powdered metal ore.

[0154] When reducing gases are used to chemically reduce metal oxides, CO, H2, or both CO and H2 chemically react with the metal oxide (e.g., Fe3O4) in a chemical reaction that reduces it to the corresponding metal (e.g., Fe) or a less reduced metal oxide (e.g., FeO is less reduced than Fe2O3). The sensible heat contained in the oxidized pyrolysis off-gas can be used to produce endothermic reactions, whether thermodynamic, kinetic, or both. The usefulness of high-temperature gases in endothermic reactions requiring heat will be recognized by skilled chemical engineers. Optionally, the hot gas from the oxidation of the pyrolysis off-gas can be used to indirectly heat the reactor or to exchange heat with another flow before being injected into the reactor. It is also possible that the high-temperature gas is at a lower temperature than the reaction into which it is injected. In that case, the high-temperature gas can be considered to be actually heating itself rather than providing heat. However, in this case, the contents of the reactor are not cooled as much as they would by the injection of cooling gas, so endothermic chemical reactions are still advantageous with relatively lower total energy consumption compared to conventional approaches.

[0155] In certain embodiments, heat is generated from partial oxidation (combustion) of the pyrolysis off-gas rather than complete oxidation, thereby intentionally producing additional reducing gases containing CO or H2, rather than combustion gases primarily containing CO2 and H2O. This heat can be used to increase the pyrolysis temperature or to heat other reactors. While partial oxidation generates less heat than complete oxidation, it produces more reducing gases, which are useful for metal oxide reduction or hydrogen production.

[0156] In some embodiments, the bioreagent comprises heavy hydrocarbons obtained during step (b), which can be converted into a reducing gas in a second reactor. The heavy hydrocarbons may originate from pyrolysis off-gases or volatile carbons remaining in the bioreagent.

[0157] The metal oxides may be, for example, iron oxide, copper oxide, nickel oxide, magnesium oxide, manganese oxide, aluminum oxide, tin oxide, zinc oxide, cobalt oxide, chromium oxide, tungsten oxide, molybdenum oxide, or combinations thereof. In some embodiments, the metal oxide is iron ore, such as hematite, magnetite, limonite, taconite, or combinations thereof.

[0158] In some embodiments, the reduced form of the selected metal oxide is a completely reduced metal (e.g., completely reduced iron, Fe 0 In other embodiments, the reduced form of the selected metal oxide is a second metal oxide having a lower oxidation state than the selected metal oxide. For example, iron in FeO has an oxidation state of +2, while iron in Fe2O3 has an oxidation state of +3.

[0159] In various embodiments, heat is used for heating in step (b), or for heating in step (d), or for heating in step (e), or for at least two of these steps, or for all three of these steps.

[0160] In some embodiments, the process further includes increasing the hydrogen content of the reducing gas via a water-gas shift reaction. Whether or not the hydrogen content is increased, the process may further include separating hydrogen from the reducing gas and subsequently recovering the hydrogen. The hydrogen can be separated from the reducing gas by one or more separation techniques selected from, for example, pressure swing adsorption, molecular sieve membrane separation, or cryogenic distillation.

[0161] In some embodiments, the reactant selected in step (d) is water. In some embodiments, the reactant in step (d) is oxygen, which may be present in a form selected from air, pure oxygen, concentrated oxygen, ozone, or a combination thereof. Concentrated oxygen refers to a gas composition containing O2 at a concentration of at least about 21 volume percent together with N2 or other gases. In certain embodiments, the reactant selected in step (d) includes a combination of water and oxygen. Another possible reactant is CO2 in the dry reforming process.

[0162] Step (d) can utilize, for example, a fixed-bed reactor or a fluidized-bed reactor. If a fixed-bed reactor is used, the fixed bed may contain or consist of bioreagents. In some embodiments, step (d) utilizes a rotary kiln.

[0163] In some embodiments, in step (c), the pyrolysis off-gas is partially or completely oxidized, thereby generating additional reducing gas and heat. In these embodiments, step (e) may further include chemically reducing the selected metal oxide in the presence of some or all of the additional reducing gas, in addition to chemically reducing the selected metal oxide in the presence of the reducing gas from step (d).

[0164] In some embodiments, the reducing gas is also oxidized, thereby generating heat. This heat can be used for heating in step (b), or for heating in step (d), or for heating in step (e), or for at least two of these steps, or for all three of these steps.

[0165] In some embodiments, the pyrolysis off-gas is converted into an additional reducing gas during step (d). For example, some or all of the pyrolysis off-gas from the pyrolysis reactor can be directed to a reactor for converting the bioreagent into a reducing gas. The same reactants that react with the bioreagent (e.g., water vapor or oxygen) can react with the pyrolysis off-gas, thereby producing an additional reducing gas (e.g., CO or H2). Alternatively or additionally, the off-gas can be converted into an additional reducing gas (e.g., CO or H2) through a water-gas shift or other equilibrium reaction. In these embodiments, the reactants that react with the off-gas may be the same as or different from the reactants that react with the bioreagent.

[0166] The pyrolysis off-gas, or the additional reducing gas produced from the off-gas, may contain at least 10 mol% hydrogen or at least 20 mol% hydrogen, specifically as provided in the summary above. Independently, the pyrolysis off-gas, or the additional reducing gas produced from the off-gas, may contain at least 10 mol% carbon monoxide or at least 20 mol% carbon monoxide. In some embodiments, the pyrolysis off-gas, or the additional reducing gas produced from the off-gas, may contain hydrogen in the range of about 1 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%, 25 mol%, 30 mol%, 35 mol%, 40 mol%, 45 mol%, or 50 mol%, or in the range between these, and at least 1 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%, 25 mol%, 30 mol%, 35 mol%, 40 mol%, 45 mol%, or 50 mol% carbon monoxide.

[0167] In some processes, step (e) is not performed. In other processes, step (e) is performed. When step (e) is performed, the process may include recovering the reduced form of the selected metal oxide, for example, through the outlet port of the reactor. Also, when step (e) is performed, steps (b) and (e) can be performed at the same location.

[0168] In some embodiments, the process is jointly installed in metal oxide mines, such as iron mines.

[0169] In some embodiments, the process is jointly installed in a metal oxide treatment plant, such as a steel mill, a taconite plant, or a direct iron reduction plant.

[0170] In certain embodiments, the entire process is located at a single site, which may be a greenfield site or an existing site. If it is an existing site, the site may include a biomass processing plant, a pyrolysis plant, a coal plant, a metal ore mine, a metal ore processing plant, a gasification plant, a steam reforming plant, or another type of plant.

[0171] In some embodiments, step (e) is performed in or upstream of the metal ore furnace. The metal ore furnace can be selected from blast furnaces, direct reducing metal furnaces, top gas recirculation blast furnaces, shaft furnaces, reverberatory furnaces, crucible furnaces, silenced furnaces, retort furnaces, flash furnaces, Tecnored furnaces, Ausmelt furnaces, ISASMELT furnaces, paddle furnaces, bogie hearth furnaces, continuous chain furnaces, pusher furnaces, rotary hearth furnaces, walking beam furnaces, electric arc furnaces, induction furnaces, basic oxygen furnaces, paddle furnaces, Bessemer furnaces, or combinations thereof.

[0172] Some variant forms are, A first reactor that thermally decomposes biomass raw materials to produce a bioreagent containing carbon and a thermal decomposition off-gas, A second reactor configured to react a bioreagent with a selected reactant, thereby generating a reducing gas, The system comprises a third reactor configured to optionally chemically reduce a selected metal oxide in the presence of a reducing gas, thereby producing a reduced form of the selected metal oxide, The system optionally further comprises one or more heating units that are in thermal communication with a first reactor, a second reactor, or (if present) a third reactor, the one or more heating units being configured to oxidize the pyrolysis off-gas, thereby generating heat.

[0173] Some variant forms are, A first reactor is configured to thermally decompose a biomass raw material, thereby producing a bioreagent containing carbon and a thermal decomposition off-gas. A second reactor configured to react a bioreagent with a selected reactant to generate a reducing gas, the second reactor being optionally configured to continuously, periodically, or finally remove activated carbon from the second reactor, The system comprises a third reactor, optionally configured to chemically reduce a selected metal oxide in the presence of a reducing gas, thereby producing a reduced form of the selected metal oxide. The system is provided, optionally comprising one or more heating units that are thermally connected to a first reactor, a second reactor, or (if present) a third reactor, wherein one or more heating units are configured to oxidize a pyrolysis off-gas, thereby generating heat.

[0174] In some systems, the first reactor is configured to operate at a thermal decomposition temperature in the range of approximately 250°C to approximately 1250°C or in between, for example, in the range of approximately 300°C to approximately 700°C or in between. The first reactor can also be configured to operate at a thermal decomposition time in the range of approximately 10 seconds to approximately 24 hours or 48 hours or in between. Other thermal decomposition times are also possible, and the thermal decomposition time depends on the raw materials, the desired product, and other reaction conditions. The thermal decomposition time is important for the process and the product, but the time can vary very widely.

[0175] In some systems, the second reactor is configured to operate at a reaction temperature in the range of approximately 300°C to approximately 1200°C or in between, for example, in the range of approximately 400°C to approximately 1000°C or in between. The second reactor can be configured to operate for a reaction time selected from, for example, approximately 1 second to approximately 1 hour. Other reaction times are also possible. The reaction time, like the pyrolysis time, can vary, but this is important for the process and the product.

[0176] In some systems, the third reactor is configured to operate at a reduction temperature in the range of approximately 500°C to approximately 2000°C or in between, for example, in the range of approximately 700°C to approximately 1800°C or in between. The third reactor can be configured to operate for a reduction time in the range of approximately 30 minutes to approximately 48 hours or in between. Other reduction times are also possible. As with the pyrolysis time, the reduction time can vary, but this is important for the process and the product.

[0177] In some embodiments, the biomass raw materials include softwood chips, hardwood chips, timber harvest residues, tree branches, tree stumps, leaves, bark, sawdust, corn, corn stalks and leaves, wheat, wheat straw, rice, rice straw, sugarcane, sugarcane bagasse, sugarcane straw, energy sugarcane, sugar beet, sugar beet pulp, sunflower, sorghum, canola, algae, pampas grass, alfalfa, switchgrass, fruits, and fruit The following are selected from shells, fruit stems, fruit peels, fruit seeds, vegetables, vegetable shells, vegetable stems, vegetable peels, vegetable seeds, grape pomace, tonsil shells, pecan shells, coconut shells, coffee grounds, food waste, commercial waste, grass pellets, hay pellets, wood pellets, cardboard, paper, paper pulp, paper packaging, paper trimmings, food packaging, construction or demolition waste, railway ties, lignin, animal manure, municipal solid waste, municipal sewage, or combinations thereof.

[0178] In some systems, the bioreagent contains total carbon in the range of about 50% to about 99% by weight or in between, for example, at least 75% by weight of carbon or at least 90% by weight of carbon. The bioreagent may also contain fixed carbon in the range of about 50% to about 99% by weight or in between, for example, at least 75% by weight of fixed carbon or at least 90% by weight of fixed carbon.

[0179] The metal oxide can be selected from iron oxide, copper oxide, nickel oxide, magnesium oxide, manganese oxide, aluminum oxide, tin oxide, zinc oxide, cobalt oxide, chromium oxide, tungsten oxide, molybdenum oxide, or a combination thereof. In some systems, the metal oxide is iron ore, such as hematite, magnetite, limonite, taconite, or a combination thereof.

[0180] The reduced form of the selected metal oxide may be a completely reduced metal, or a second metal oxide having a lower oxidation state than the selected metal oxide (i.e., in a partial but incomplete reduction of the starting metal oxide).

[0181] In some embodiments, the system comprises a first reactor, a second reactor, a third reactor, a heating unit that is in thermal communication with at least two of such reactors, or all three of such reactors.

[0182] In some systems, a second reactor is configured to increase the hydrogen content of the reducing gas via a water-gas shift reaction. In these or other systems, the system may further include an additional reactor in fluid communication with the second reactor, the additional reactor being configured to increase the hydrogen content of the reducing gas via a water-gas shift reaction. The system may further include a separation unit configured to separate hydrogen from the reducing gas. Exemplary separation units include pressure swing adsorption units, molecular sieve membranes, or cryogenic distillation units.

[0183] In some systems, the selected reactant is water, which may be in the form of water vapor. In some embodiments, the selected reactant is oxygen. The reactant may also be a combination of water and oxygen.

[0184] The second reactor may be, for example, a fixed-bed reactor, a rotary kiln, or a fluidized-bed reactor.

[0185] In some embodiments, the system further comprises an off-gas reactor configured to partially oxidize the pyrolysis off-gas, thereby generating an additional reducing gas. In these embodiments, the off-gas reactor can be in fluid communication with a third reactor.

[0186] In some embodiments, a second reactor is configured to receive some or all of the pyrolysis off-gas to allow its conversion to additional reducing gases. The same reactants that react with the bioreagents (e.g., water vapor) can react with the pyrolysis off-gas, thereby producing additional reducing gases (e.g., CO or H2). Figures 1-4 illustrate any use of the pyrolysis off-gas to produce more reducing gases, which can be done instead of, or in addition to, the combustion of the pyrolysis off-gas to generate heat.

[0187] In some embodiments, one or more heating units are configured to oxidize a reducing gas, thereby generating heat. This heat can be used to heat a first reactor, a second reactor, or (if present) a third reactor.

[0188] A third reactor may or may not be present. In some embodiments, a third reactor is present in the system, and the system includes an outlet from the third reactor configured to recover the reduced form of the selected metal oxide. For example, a screw conveyor can be installed at or near the bottom of the third reactor to continuously or periodically remove the metal product (reduced form of the metal oxide). If a third reactor is present, the first and third reactors can be installed together in the same location.

[0189] As used herein, “reactor” may refer to a single reaction vessel or a reaction zone contained within a reaction vessel. If a single reactor contains multiple reaction zones, the number of zones may be two, three, four, or more.

[0190] The first and second reactors may be physically contained within a single reactor such that the first reactor is the first zone and the second reactor is the second zone within the same physical apparatus as the first zone. In these or other embodiments, the second and third reactors may be physically contained within a single reactor such that the second reactor is the first zone and the third reactor is the second zone within the same physical apparatus as the first zone (see, for example, Figure 4). In certain embodiments, the first, second, and third reactors are all physically contained within a single reactor such that the first reactor is the first zone, the second reactor is the second zone, and the third reactor is the third zone within a common physical apparatus.

[0191] It should also be noted that multiple physical devices can be used in the reactor in series or in parallel. For example, the first reactor may consist of two physical reaction vessels operating in series (sequentially), in parallel, or a hybrid thereof.

[0192] Similarly, the second reactor may consist of two physical reaction vessels operating in series (sequentially), in parallel, or a hybrid thereof. Multiple reaction vessels for the second reactor may be advantageous, for example, if it is desirable to produce several different types of activated carbon, or if it is desirable to produce activated carbon from one vessel but not from another. In other words, the second primary reactor may be configured to react a bioreagent with selected reactants to thereby produce a reducing gas, and the second primary reactor may be configured to remove the activated carbon from the second primary reactor continuously, periodically, or finally. On the other hand, an auxiliary second reactor may also be configured to react a bioreagent with selected reactants to thereby produce a reducing gas, but not, for example, to remove activated carbon from the auxiliary second reactor.

[0193] In some embodiments, the system is jointly installed in a metal oxide mine.

[0194] In some embodiments, the system is installed in conjunction with a metal oxide processing plant, such as a steel mill, a taconite plant, or a direct iron reduction plant.

[0195] In certain embodiments, the entire system is located at a single site, which may be a greenfield site or an existing site. If it is an existing site, the site may include a biomass processing plant, a pyrolysis plant, a coal plant, a metal ore mine, a metal ore processing plant, a gasification plant, a steam reforming plant, or another type of plant.

[0196] In some embodiments, the third reactor is either a metal ore furnace or located upstream of a metal ore furnace (or there is a third reactor located upstream of a metal ore furnace and a fourth reactor which is a metal ore furnace). The metal ore furnace can be selected from blast furnaces, direct reducing metal furnaces, top gas recirculation blast furnaces, shaft furnaces, reverberatory furnaces, crucible furnaces, silenced furnaces, retort furnaces, flash furnaces, Tecnored furnaces, Ausmelt furnaces, ISASMELT furnaces, paddle furnaces, bogie hearth furnaces, continuous chain furnaces, pusher furnaces, rotary hearth furnaces, walking beam furnaces, electric arc furnaces, induction furnaces, basic oxygen furnaces, paddle furnaces, Bessemer furnaces, or combinations thereof.

[0197] Other variations of this disclosure include: (a) To provide biomass raw materials, (b) The process of thermally decomposing biomass raw materials to produce bioreagents containing carbon and thermal decomposition off-gases, (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting a bioreagent with a selected reactant to generate a reducing gas, (e) Chemically reduce the selected metal oxide in the presence of the reducing gas from step (d), thereby producing the reduced form of the selected metal oxide. (f) Provide a metal product generated by the process, which includes recovering a metal product containing the reduced form of the selected metal oxide.

[0198] Further variations of this disclosure include: (a) To provide biomass raw materials, (b) The process of thermally decomposing biomass raw materials to produce bioreagents containing carbon and thermal decomposition off-gases, (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting a bioreagent with a selected reactant to generate a reducing gas, (e) Separating hydrogen from a reducing gas, wherein the hydrogen is optionally separated by one or more separation techniques selected from pressure swing adsorption, molecular sieve membrane separation, or cryogenic distillation. (f) Provide a renewable hydrogen product produced by a process, which includes recovering a renewable hydrogen product containing hydrogen.

[0199] carbon 14 C / 12 Measuring carbon isotope ratios (in solid carbon, or in vaporized carbon such as CO, CO2, or CH4) is a proven technique. A similar concept can be applied to hydrogen. 2 H / 1 The H isotope ratio is measured. 2 H is deuterium (also known as D). Fossil sources tend to be depleted of deuterium compared to biomass. See, incorporated herein by reference, Schiegl et al., "Deuterium content of organic matter," Earth and Planetary Science Letters, Vol. 7, No. 4, 1970, pp. 307-313, and Hayes, "Fractionation of the Isotopes of Carbon and Hydrogen in Biosynthetic Processes," Mineralogical Society of America, National Meeting of the Geological Society of America, Boston, MA, 2001.

[0200] In particular, the natural deuterium content of organically bound hydrogen exhibits systematic variation depending on the origin of the sample. Hydrogen in both marine and terrestrial plants contains several percent less deuterium than the water in which the plants grew. Coal and oil are even more depleted of deuterium than plants, and natural gas is even more depleted of deuterium than the coal or oil from which it is derived. In this disclosure, “renewable hydrogen” refers to hydrogen contained in water (H2O) reactants that can be used to react with carbon or CO to form H2, regardless of the renewable nature of the hydrogen. 2 H / 1 The H isotope ratio is determined by correlating it with the renewableness of the starting feedstock. On average, water contains 6,400 hydrogen atoms. 1 It contains approximately one deuterium atom per hydrogen atom. The ratio of deuterium atoms to hydrogen atoms in renewable biomass is slightly lower than 1 / 6,400, and the ratio of deuterium atoms to hydrogen atoms in non-renewable fossil sources (e.g., mined coal or mined natural gas) is even lower than that in renewable biomass. Therefore, 2 H / 1 H isotope ratios correlate with the renewability of hydrogen, and higher 2 H / 1 The H isotope ratio indicates a higher renewable hydrogen content. 2 H / 1 The 1H isotope ratio may be about 0.0002 to about 0.001, for example, about 0.0002 to about 0.005. The hydrogen contained in the specific reducing gas composition disclosed herein 2 H / 1 The hydrogen isotope ratio is higher than that of other equivalent reducing gas compositions obtained from fossil resources rather than biomass. In some embodiments, the hydrogen contained in the reducing gas composition 2 H / 1 The 1H isotope ratio is higher than approximately 1% to approximately 100% or any number in between, for example, from approximately 1%, 5%, 10%, 25%, 50%, or 100% or any number in between.

[0201] Renewable hydrogen can be recognized in the market in various ways, such as through renewable energy standards, renewable energy credits, and renewable identification numbers. For example, a refinery that uses renewable hydrogen in the production of gasoline can receive renewable energy credits for such H2 content. In metal products such as steel, renewable hydrogen can be utilized during metal formation (e.g., reduction of metal ore with H2), or it may be a measurable alloying element in the final product.

[0202] In some embodiments of this disclosure, the hydrogen product is characterized as at least 50% renewable hydrogen according to hydrogen isotope analysis. In various embodiments, the hydrogen product is characterized as at least 80%, at least 90%, at least 95%, or at least 99% renewable hydrogen. In certain embodiments, the hydrogen product is characterized as fully renewable hydrogen.

[0203] In some hydrogen products, the hydrogen is characterized as fully renewable hydrogen, and any residual carbon contained in the hydrogen product is 14 C / 12 It is essentially a completely renewable form of carbon, determined by the measurement of its 1C isotope ratio.

[0204] The reactants selected in step (d) may be, for example, water, oxygen, or a mixture thereof. Oxygen may be present in a form selected from air, pure oxygen, concentrated oxygen, ozone, or a combination thereof.

[0205] In some embodiments, the reducing gas may contain at least 10 mol% or at least 25 mol% hydrogen. In some embodiments, the reducing gas may contain at least 10 mol% or at least 25 mol% carbon monoxide.

[0206] In some embodiments, the hydrogen product is produced by a process that further includes increasing the hydrogen content of the reducing gas via a water-gas shift reaction.

[0207] In some embodiments, the pyrolysis off-gas is partially oxidized, thereby generating additional reducing gas and heat.

[0208] In various embodiments, hydrogen is separated by pressure swing adsorption, molecular sieve membrane separation, cryogenic distillation, or a combination thereof.

[0209] The hydrogen product may contain at least 50 mol% hydrogen. In some embodiments, the hydrogen product may contain at least 90 mol% hydrogen. In various embodiments, the hydrogen product may range from or between about 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 99, or 100 mol%.

[0210] In some hydrogen products, the hydrogen product contains at most about 1 mol% nitrogen or is substantially nitrogen-free. In various embodiments, the hydrogen product contains nitrogen in the range of about 10, 9, 8, 7, 6, 5, 4, 3, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.05, 0.04, 0.03, 0.02, or 0.01 mol% or in the range between these. In this disclosure, a hydrogen product that is "substantially nitrogen-free" means that there is no nitrogen in the product that can be detected by conventional analytical techniques.

[0211] Some variations provide reducing gas compositions for reducing metal oxides, comprising hydrogen in which at least 50% is renewable hydrogen according to hydrogen isotope analysis. In various embodiments, the reducing gas composition comprises hydrogen characterized as at least 80%, at least 90%, at least 95%, or at least 99% renewable hydrogen. In a particular embodiment, the reducing gas composition comprises hydrogen characterized as completely renewable hydrogen.

[0212] The compositional profile of the reducing gas composition may contain about or at least about 50 mol%, 60 mol%, 70 mol%, 80 mol%, 85 mol%, 90 mol%, 95 mol%, 96 mol%, 97 mol%, 98 mol%, 99 mol%, 99.5 mol%, or 99.9 mol% of H2, regardless of whether the hydrogen is certified or characterized as renewable hydrogen. The remainder of the reducing gas composition may contain CO, CO2, H2O, CH4, N2, or other components.

[0213] Some variations of this disclosure provide reducing gas compositions for reducing metal oxides, wherein the reducing gas compositions contain hydrogen isotopes 2 H / 1 It contains at least 25 mol% hydrogen, which is at least 50% renewable hydrogen according to H analysis.

[0214] In some embodiments, the reducing gas composition contains at least 50 mol% hydrogen, at least 75 mol% hydrogen, or at least 90 mol% hydrogen. In various embodiments, the reducing gas composition contains hydrogen in the range of about 50, 55, 60, 65, 70, 75, 80, 85, 90, or 95 mol% or in between.

[0215] In some reducing gas compositions, hydrogen is a hydrogen isotope. 2 H / 1 According to H analysis, it is characterized as at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% renewable hydrogen. In some embodiments, hydrogen isotopes 2 H / 1 According to H analysis, it is characterized as completely (100%) renewable hydrogen.

[0216] The reducing gas composition may further comprise a carbon-containing gas including CO, CO2, or CH4, or the reducing gas composition may further consist essentially of a carbon-containing gas consisting essentially of CO, CO2, or CH4. The carbon-containing gas is 14 C / 12 as determined from measurement of the C isotope ratio, may be at least 50% renewable, at least 90% renewable, or essentially completely renewable. In some embodiments, the reducing gas composition comprises a carbon-containing gas, and the hydrogen is a hydrogen isotope 2 H / 1 according to H analysis, characterized as at least 90% renewable hydrogen, or essentially completely renewable hydrogen.

[0217] In some reducing gas compositions, the reducing gas composition further comprises carbon monoxide, wherein the carbon monoxide is 14 C / 12 as determined from measurement of the C isotope ratio, at least 50% renewable, at least 90% renewable, or essentially completely renewable. In some embodiments, the reducing gas composition further comprises carbon monoxide, and the hydrogen is a hydrogen isotope 2 H / 1 according to H analysis, characterized as at least 90% renewable hydrogen, or essentially completely renewable hydrogen. In some reducing gas compositions, the molar ratio of hydrogen to carbon monoxide is at least 2.

[0218] In some embodiments, the reducing gas composition comprises at most about 1 mol% N2, at most about 0.5 mol% N2, at most about 0.1 mol% N2, or is essentially free of N2. In various embodiments, the reducing gas composition comprises N2 in a range from or ranging between about 10, 9, 8, 7, 6, 5, 4, 3, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.05, 0.04, 0.03, 0.02, or 0.01 mol%. In the present disclosure, "substantially free of nitrogen" with respect to a hydrogen product means that no detectable nitrogen is present in the reducing gas composition by conventional analytical techniques.

[0219] The process disclosed in the present specification is an environmentally friendly technology with reduced carbon dioxide emissions. When the starting material is biomass containing biological and renewable carbon, the carbon obtained by pyrolysis is also biological. This can be determined by measuring the carbon 14 C / 12 C isotope ratio, for example using ASTM D6866. In some embodiments, all of the processed carbon is renewable. In other embodiments, less than all of the carbon is renewable.

[0220] Any biological carbon oxidized to carbon dioxide produces biological CO2. This can also be shown from measurement of the carbon 14 C / 12 C isotope ratio in the generated CO2. This biological CO2 derived from biomass returns to the environment to be reabsorbed by biomass growing via photosynthesis. In this way, net CO2 emissions are greatly reduced. Furthermore, the hydrogen content of the starting biomass substantially reduces the net CO2 emissions of the process. This is because the hydrogen in the biomass becomes H2 in the reducing gas. H2 can cause chemical reduction of metal oxides in substantially the same manner as CO does, but oxidation of H2 produces H2O instead of CO2, and H2O is not considered a problematic greenhouse gas.

[0221] Another reason that the disclosed process is environmentally superior to conventional technology relates to energy balance. Reduction of metal oxides inherently requires energy because the overall chemical reaction is endothermic. Even known approaches of electrochemical conversion that decompose metal oxides into metal and oxygen, thereby avoiding any direct CO2 generation, require large amounts of electricity, which is usually produced from non-renewable sources. Conventional metal ore processing utilizes large amounts of coal to generate the required heat (from coal combustion) and provide carbon for the reduction chemical reaction. In contrast, some embodiments of the present disclosure provide an integrated bioreduction process that utilizes carbon and hydrogen in an energy efficient manner. This avoids pollution from coal combustion.

[0222] The integrated bioreduction of metal ores significantly reduces the environmental impact compared to the conventional use of fossil fuels such as coal. Conventional approaches are linked to "carbon intensity," which is the amount of net carbon dioxide produced per ton of ore processed. "CO2 equivalent carbon intensity" can also be defined as the equivalent amount of net carbon dioxide produced per ton of ore processed. "Carbon dioxide equivalent" or "CO2e" represents the amount of CO2 that has an equivalent global warming effect. For example, in the case of metal mining processing, the average is 11.9 kg CO2 / ton (Tost et al., "Metal Mining's Environmental Pressures: A Review and Updated Estimates on CO2 Emissions, Water Use, and Land Requirements," Sustainability 2018, 10, 2881, incorporated by reference). In various embodiments, the processes disclosed herein may feature a reduction in carbon intensity or CO2 equivalent carbon intensity of about 50%, 60%, 70%, 80%, 90%, 95%, or 99% compared to the prior art. In various embodiments, the processes disclosed herein may feature a carbon intensity or CO2 equivalent carbon intensity of about 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0.5, 0.4, 0.3, 0.2, or 0.1 kg CO2 / ton or less. In this disclosure, most or all of the CO2 produced may be biocarbon dioxide, and as a result, the effective carbon intensity may be very low, zero, or even negative if net carbon sequestration is present in the final product, such as carbon steel.

[0223] Some variations are based on the understanding that oxygen can be intentionally restricted in the combustion of the pyrolysis off-gas, producing more CO (rather than CO2 as in complete combustion), which can then be used as a reducing agent. The production of CO from partial oxidation still provides some heat, but less than that of conventional complete oxidation to CO2. These variations take advantage of the discovery that the heat produced may be sufficient to carry out the endothermic reduction of the metal oxide, which chemically utilizes the CO produced from the partial oxidation.

[0224] Based on the above understanding, several variations provide a method for optimizing the reduction of metal oxides, comprising: thermally decomposing biomass to obtain carbon and thermal decomposition off-gas; oxidizing the thermal decomposition off-gas with a deliberately smaller amount of oxygen than the stoichiometric amount of oxygen, thereby generating heat and reducing gases; and using the heat and reducing gases to reduce metal oxides.

[0225] "Combustion stoichiometric amount of oxygen" is the amount of oxygen that completely oxidizes carbon-containing or hydrogen-containing components to CO2 or H2O, respectively, without being in a stoichiometric excess, whether present in air, pure oxygen, or oxygen-enriched air. When the pyrolysis off-gas is intentionally oxidized to less than the stoichiometric amount for combustion, the oxygen used as the percentage of combustion stoichiometric amount of oxygen may be about 10% to about 99%, about 25% to about 90%, for example, about 40% to about 80%. In various embodiments, this percentage is about, at least about, or at most about 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95%. These percentages are based on the molar basis of oxygen being in the O2 form.

[0226] In some embodiments, metal oxides can be reduced using carbon directly, for example, by reacting the metal oxide with carbon to produce the metal (or a less reduced form of the metal) and carbon monoxide or carbon dioxide. Alternatively or additionally, metal oxides can be reduced indirectly using carbon by converting the carbon to carbon monoxide and then reacting the carbon monoxide with the metal oxide.

[0227] Generation of reducing gases Next, the generation of reducing gas (also referred to herein as "bioreducing agent gas") will be described further. The conversion of the bioreagent into reducing gas takes place in a reactor which may be referred to herein as a second reactor, gasifier, or bioreducing agent forming unit.

[0228] Reactants are used to react with bioreagents to produce a reducing gas. The reactants can be selected from oxygen, water vapor, or a combination thereof. In some embodiments, oxygen is mixed with water vapor and the resulting mixture is added to a second reactor. Adding oxygen or oxygen-concentrated air can induce exothermic reactions such as partial or total oxidation of carbon by oxygen, thereby achieving a more favorable H2 / CO ratio in the reducing gas, (iii) increasing the yield of the reducing gas, or (iv) increasing the purity of the reducing gas by reducing the amount of, for example, CO2, pyrolysis products, tar, aromatic compounds, or other undesirable products.

[0229] In some embodiments, water vapor is a reactant. Water vapor (i.e., H2O in the vapor phase) can be introduced into a second reactor by one or more input streams. The water vapor may include water vapor produced by moisture contained in the bioreagent input, as well as water vapor produced by any chemical reaction that produces water.

[0230] All references to "ratios" of chemical species in this specification refer to molar ratios unless otherwise indicated. For example, an H2 / CO ratio of 1 means 1 mole of hydrogen per mole of carbon dioxide.

[0231] Steam reforming, partial oxidation, water-gas shift (WGS), or combustion reactions can occur when oxygen or steam is added. Exemplary reactions include, for example, the cellulose repeating units (C6H) found in cellulosic feedstocks. 10 Regarding O5), the following applies. Similar reactions can occur using any carbon-containing raw material. Steam reforming C6H 10 O5 + H2O → 6CO + 6H2 Partial oxidation C6H 10 O5 + 1 / 2O2 → 6CO + 5H2 Water-based gas shift: CO + H2O ⇔ H2 + CO2 Complete combustion C6H 10 O5 + 6O2 → 6CO2 + 5H2O

[0232] The second reactor is any reactor capable of initiating a chemical reaction that produces a reducing gas. Conventional steam reformers known in the art can be used with or without a catalyst. Other possibilities include self-thermal reformers, partial oxidation reactors, and multi-stage reactors combining several reaction mechanisms (e.g., partial oxidation followed by a water-gas shift). The reactor configuration can be a fixed bed, a fluidized bed, multiple microchannels, or several other configurations.

[0233] In some embodiments, the total amount of water vapor as a reactant is at least about 0.1 moles of water vapor per mole of carbon in the feed material. In various embodiments, at least about 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0, or more moles of water vapor per mole of carbon are added or present. In some embodiments, about 1.5 to 3.0 moles of water vapor are added or present per mole of carbon.

[0234] The amount of steam added to the second reactor can vary depending on factors such as the conditions of the pyrolysis reactor. When pyrolysis produces a carbon-enriched solid material, generally more steam (or more oxygen) is used to add the necessary H and O atoms to the available C, thereby producing CO and H2. From a system-wide perspective, the moisture content of the feed material can be taken into consideration when determining how much additional water (steam) to add in the process.

[0235] An exemplary ratio of oxygen to water vapor (O2 / H2O) in the second reactor is equal to or less than one of the following values: approximately 2, 1.5, 1, 0.5, 0.2, 0.1, 0.05, 0.02, 0.01, or at most one of these values. When the O2 / H2O ratio is at least approximately 1, the combustion reaction begins to dominate over partial oxidation, which can result in an undesirable low CO / CO2 ratio.

[0236] In some embodiments, oxygen free of water vapor is used as a reactant. Oxygen may be added in a substantially pure form, or optionally supplied to the process via the addition of oxygen-concentrated air. In some embodiments, air that is not oxygen-concentrated is added. In other embodiments, concentrated air from an off-spec or recirculated flow can be used, for example, from a nearby air separation plant. In some embodiments, using concentrated air with a reduced amount of N2 (i.e., at most about 79 volume%) results in less N2 in the resulting reduced gas. Removal of N2 can be costly, and therefore, a method that produces a reduced gas with little or no N2 may be desirable.

[0237] In some embodiments, the presence of oxygen alters the H2 / CO ratio in the reducing gas compared to the ratio produced by the same method in the absence of oxygen. The H2 / CO ratio of the reducing gas can be about 0.5 to about 2.0, for example, about 0.75 to 1.25, about 1 to 1.5, or about 1.5 to 2.0. As recognized, an increased water-gas shift (due to a higher water vapor addition rate) produces a higher H2 / CO ratio, for example, at least 2.0, 3.0, 4.0, 5.0, or even higher, which may be desirable for certain applications, including hydrogen production.

[0238] A catalyst can be used in the second reactor. The catalyst may include, but is not limited to, alkali metal salts, alkaline earth metal oxides and salts, inorganic substances or ash in coal, transition metals and their oxides and salts, and eutectic salt mixtures. Specific examples of catalysts, but are not limited to, potassium hydroxide, potassium carbonate, lithium hydroxide, lithium carbonate, cesium hydroxide, nickel oxide, nickel-substituted synthetic mica montmorillonite (NiSMM), NiSMM-supported molybdenum, iron hydroxy oxide, iron nitrate, iron-calcium impregnated salt, nickel uranyl oxide, sodium fluoride, and cryolite.

[0239] Other exemplary catalysts include, but are not limited to, nickel, nickel oxide, rhodium, ruthenium, iridium, palladium, and platinum. Such catalysts can be coated or deposited on one or more support materials, such as gamma-alumina (optionally doped with stabilizing elements such as magnesium, lanthanum, or barium).

[0240] Prior to addition to the system, any catalyst can be pretreated or activated using known techniques that affect total surface area, active surface area, site density, catalyst stability, catalyst lifetime, catalyst composition, surface roughness, surface dispersion, porosity, density, or thermal diffusivity. Pretreatment of the catalyst includes, but is not limited to, calcination, addition of a washcoat, particle size reduction, and surface activation by thermal or chemical means.

[0241] The addition of the catalyst can be performed by first dissolving or slurrying the catalyst in a solvent such as water or any hydrocarbon that can be gasified or reformed. In some embodiments, the catalyst is added by directly injecting such slurry into the vessel. In some embodiments, the catalyst is added to steam, and the steam / catalyst mixture is added to the system. In these embodiments, the added catalyst can be at or near its equilibrium solubility in the steam, or can be introduced as particles entrained in the steam, thereby being introduced into the system.

[0242] Material can generally be conveyed into and out of the second reactor by a single screw, twin screw, ram, or the like. Material can be conveyed mechanically by physical force (metal contact), pressure-driven flow, pneumatically driven flow, centrifugal flow, gravity flow, fluidized flow, or some other known means for moving solid and gas phases. A fixed bed of biomass reagent pellets can be utilized in the second reactor, particularly in embodiments using a metal oxide bed disposed over a carbon bed (e.g., Figure 4), thereby producing mechanically robust activated carbon pellets.

[0243] In some embodiments, a second reactor employs the gasification of the bioreagent, thereby producing a reducing gas. Gasification is carried out at high temperatures, such as at least about 600°C and no higher than about 1100°C. Lower-reactive bioreagents use higher operating temperatures. The amount of reactant introduced (e.g., air, oxygen, concentrated air, or an oxygen-water vapor mixture) can be a major factor controlling the gasification temperature. Operating pressures from atmospheric pressure to about 50 bar have been used in biomass gasification. The gasifier also uses reactant, generally air, high-purity oxygen, water vapor, or some mixture of these gases.

[0244] Gasification systems can be distinguished based on the means of supporting the solid within the vessel, the direction of both solid and gas flow, and the method of supplying heat to the reactor. Whether the gasification system operates at near atmospheric pressure or high pressure, and whether it is air-blown or oxygen-blown, are also distinctive features. Common classifications include fixed-bed upward flow, fixed-bed downward flow, bubbling fluidized bed, and circulating fluidized bed.

[0245] Fixed-bed gasifiers are generally unable to handle fibrous herbaceous feedstocks such as wheat straw, corn stalks and leaves, or garden waste. However, in the disclosed process, the biomass is first thermally decomposed into bioreagents, which are then gasified. These bioreagents can be gasified using a fixed-bed gasifier.

[0246] Recirculating fluidized bed gasification technology is available from Lurgi and Foster Wheeler and represents the majority of existing gasification technologies used for biomass and other wastes. Bubbling fluidized bed gasification (e.g., U-GAS® technology) is commercially used.

[0247] Direct heating gasification systems carry out endothermic and exothermic gasification reactions within a single reaction vessel, requiring no additional heating. In contrast, indirect heating gasification systems use an external heat source. Indirect heating gasification systems generally use two vessels. The first vessel gasifies the feed with steam (endothermic process). Heat is supplied by circulating a heat transfer medium, usually sand. The reducing gas and solid char produced in the first vessel are separated along with the sand. The mixed char and sand are fed into a second vessel, where the char is burned with air and the sand is heated. The hot sand is circulated back to the first vessel.

[0248] Bioreagents can be introduced into the gasifier as a "dry feed" (optionally containing water but not free liquid phase) or as a slurry or suspension in water. Dry feed gasifiers can enable high carbon conversion per pass to reducing gas and good energy efficiency. In dry feed gasifiers, the energy released by the gasification reaction can cause the gasifier to reach extremely high temperatures. This problem can be solved by using a wet wall design.

[0249] In some embodiments, the feedstock to the gasifier is a bioreagent having a high hydrogen content. The resulting reduced gas is relatively hydrogen-concentrated and has a high H2 / CO ratio, for example, H2 / CO > 1.5 or higher.

[0250] In some embodiments, the feedstock to the gasifier is a bioreagent with a low hydrogen content. The resulting reduced gas is expected to have a relatively low H2 / CO ratio. In downstream processes using H2 / CO > 1, it may be desirable to inject water or steam into the gasifier to mitigate the gasifier temperature (by sensible or endothermic chemistry) and shift the H2 / CO ratio to a higher, more desirable ratio. The addition of water can also contribute to temperature mitigation by endothermic consumption via steam reforming chemistry. In steam reforming, H2O reacts with carbon or hydrocarbons such as tar or benzene / toluene / xylene to produce a reduced gas and lower the adiabatic gasification temperature.

[0251] In certain variants, the gasifier is a fluidized bed gasifier, such as a bubbling fluidized bed gasifier. Fluidization results in a substantially uniform temperature within the gasifier bed. Fluidized bed materials such as alumina sand or silica sand can reduce potential wear problems. The gasifier temperature can be adjusted to a sufficiently low temperature so that the ash particles do not begin to change from a solid to a molten state, which can cause coagulation and loss of fluidization within the gasifier.

[0252] When a fluidized bed gasifier is used, the total flow rate of all components should be such that the gasifier bed is fluidized. The total gas flow rate and bed diameter establish the gas velocity through the gasifier. A precise velocity must be maintained to ensure proper fluidization.

[0253] In variations, the type of gasification apparatus may be co-flow slagging, co-flow non-slagging, transport, bubbling fluidized bed, circulating fluidized bed, or fixed bed. Some embodiments utilize a gasification catalyst.

[0254] A circulating fluidized bed gasification system can be used in which gas, sand, and raw materials are moved together. Exemplary transport gases include recirculated product gas, combustion gas, or recirculated gas. The high heat transfer rate from the sand ensures rapid heating of the raw materials, and ablation is expected to be stronger than in a conventional fluidized bed. A separator can be used to separate the reducing gas from the sand and char particles. The sand particles can be reheated in a fluidized burner vessel and recycled to the reactor.

[0255] In some embodiments where a counterflow fixed-bed gasifier is used, the reactor includes a fixed bed of raw materials through which a gasifying agent (such as steam, oxygen, or recirculated gas) flows in a counterflow configuration. The ash is removed by drying or as slag.

[0256] In some embodiments where a parallel-flow fixed-bed gasifier is used, the reactor is similar to that of a counter-flow type, but the gasifying agent gas flows in parallel with the raw materials. Heat is added to the top of the bed by burning a small amount of raw materials or from an external heat source. The generated gas exits the reactor at a high temperature, and much of this heat is transferred to the gasifying agent added to the top of the bed, resulting in good energy efficiency.

[0257] In some embodiments where a fluidized bed reactor is used as a second reactor, the raw materials are fluidized in recirculated gas, oxygen, air, or steam. The ash can be removed as heavy aggregates by drying or defluidification. The conversion rate can be increased by using solid recirculation or subsequent combustion. Fluidized bed reactors are useful for raw materials that form highly corrosive ash that would damage the walls of the slag reactor.

[0258] In some embodiments where a co-flow gasifier is used, the bioreagent is gasified in parallel with oxygen, air, or a recirculated gas. The gasification reaction takes place in a dense cloud of very fine particles. High temperatures can be used, thereby reducing the amount of tar and methane in the reducing gas.

[0259] In co-bed reactors, the operating temperature can easily exceed the ash melting temperature, so most of the ash is removed as slag. Smaller portions of the ash are produced as very fine dry fly ash or as fly ash slurry. Some co-bed reactors have internal water-cooled or steam-cooled walls covered with partially solidified slag.

[0260] The gasification chamber can be designed, through a suitable configuration of the freeboard or the use of an internal cyclone, to maintain carryover from the solid downstream operation at a level suitable for heat recovery. Unreacted biological reagents can be drawn out from the bottom of the gasification chamber, cooled, and recovered.

[0261] The gasification unit may include one or more catalysts, such as catalysts effective for partial oxidation of carbon-containing species, reverse water-gas shift, or dry (CO2) reforming.

[0262] In some embodiments, a bubbling fluidized bed defoliation reactor is used as a second reactor. The reactor is heated, at least partially, to about 600°C by a high-temperature recirculating gas flow, which is lower than the expected slag temperature of the biomass. Steam, oxygen, or air can also be introduced into the second reactor.

[0263] The second reactor can be designed, by appropriate configuration of the freeboard or by the use of an internal cyclone, to maintain solid carryover at a level suitable for downstream heat recovery. Unreacted char can be drawn out from the bottom of the defoliation chamber, cooled, and then supplied to a utility boiler to recover the remaining heat of this flow.

[0264] When a fluidized bed gasifier is used as a second reactor, the raw materials can be introduced into a bed of high-temperature sand fluidized by a gas, such as a recirculating gas. The term "sand" as used herein also includes similar substantially inert materials such as glass particles and recovered ash particles. The high heat transfer rate from the fluidized sand can result in rapid heating of the raw materials. Some ablation due to friction with the sand particles may occur. Heat can be supplied by heat exchanger tubes through which a high-temperature combustion gas flows.

[0265] A circulating fluidized bed reactor, in which gas, sand, and raw materials move together, can be used as a second reactor. Exemplary transport gases include recirculated product gas, combustion gas, or recirculated gas. The high heat transfer rate from the sand ensures rapid heating of the raw materials, and ablation is expected to be stronger than in a conventional fluidized bed. A separator can be used to separate the reducing gas from the sand and char particles. The sand particles can be reheated in a fluidized burner vessel and recycled back into the reactor.

[0266] In some embodiments where a countercurrent fixed-bed reactor is used as a devolatile unit, the reactor includes a fixed bed of raw materials through which a gasifying agent (such as steam, oxygen, or recirculated gas) flows in a countercurrent configuration. The ash is removed by drying or as slag.

[0267] In some embodiments where a parallel-flow fixed-bed reactor is used as a devolatile unit, the reactor is similar to a counter-flow reactor, but the gasifying agent gas flows in parallel with the raw materials. Heat is added to the top of the bed by burning a small amount of raw materials or from an external heat source. The reducing gas leaves the reactor at a high temperature, and much of this heat is transferred to the reactants added to the top of the bed, resulting in good energy efficiency. In this configuration, the tar passes through a high-temperature carbon bed, so the tar level is expected to be lower than when using a counter-flow reactor.

[0268] In some embodiments where a fluidized bed reactor is used as a defoliation unit, the raw materials are fluidized in recirculated gas, oxygen, air, or steam. Ash is removed as heavy aggregates that are dried or defluidified. The conversion rate can be increased by using solid recirculation or subsequent combustion.

[0269] To improve heat and mass transfer, water can be introduced into a second reactor using nozzles, which are generally mechanical devices designed to control the direction or characteristics of a fluid flow as it enters a sealed chamber or pipe through an orifice. Nozzles can reduce the size of water droplets, thereby producing a fine mist of water. Nozzles can be selected from spray nozzles (similar to fuel injectors), swirling nozzles that spray liquid tangentially, and so on.

[0270] The water source can include, for example, process condensate, other recirculated water, wastewater, makeup water, boiler feedwater, or direct piping from tap water. The water can optionally be washed, purified, treated, ionized, distilled, etc., first. When several water sources are used, various volume ratios of the water sources are possible. In some embodiments, the water for the second reactor is wastewater.

[0271] In some variations, the reducing gas from the second reactor is filtered, purified, or otherwise prepared before being converted into another product. For example, the cooled reducing gas can be introduced into a preparation unit, where benzene, toluene, ethylbenzene, xylene, sulfur compounds, nitrogen, metals, or other impurities are optionally removed from the reducing gas.

[0272] Some embodiments of this disclosure include a reducing gas purification unit downstream of the second reactor. The reducing gas purification unit is not particularly limited in its design. Exemplary reducing gas purification units include cyclones, centrifuges, filters, membranes, solvent-based systems, and other means for removing particulate matter or other specific contaminants.

[0273] In some embodiments, an acid gas removal unit is included downstream of the second reactor. The acid gas removal unit is not particularly limited and may be any means known in the art for removing H2S, CO2, or other acid gases from the reducing gas.

[0274] Examples of acidic gas removal steps include the removal of CO2 using one or more solvents for CO2, or the removal of CO2 using a pressure swing adsorption unit. Suitable solvents for reactive solvent-based acidic gas removal include monoethanolamine, diethanolamine, methyldiethanolamine, diisopropylamine, and aminoethoxyethanol. Suitable solvents for physical solvent-based acidic gas removal include polyethylene glycol dimethyl ether (e.g., Selexol® process) and chilled methanol (e.g., Rectisol® process).

[0275] The reducing gas produced as described in accordance with this disclosure can be utilized in many ways. Generally, the reducing gas can be chemically converted or purified to hydrogen, carbon monoxide, methane, olefins (such as ethylene), oxygenated compounds (such as dimethyl ether), alcohols (such as methanol and ethanol), paraffins, and other hydrocarbons. The reducing gas can be converted by Fischer-Tropsch chemistry into linear or branched C5-C5 compounds. 15 Hydrocarbons, diesel fuels, gasoline, waxes, or olefins can be converted into mixed alcohols by various catalysts, isobutane by isosynthesis, ammonia by hydrogen production and the subsequent Haber process, aldehydes and alcohols by oxosynthesis, and many derivatives of methanol, including dimethyl ether, acetic acid, ethylene, propylene, and formaldehyde, by various processes. The reducing gas can also be converted into energy using energy conversion devices such as solid oxide fuel cells, Stirling engines, microturbines, internal combustion engines, thermogenerators, scroll expanders, gas burners, or thermophotovoltaic devices.

[0276] Activated carbon recovery Next, I will explain further about the recovery of activated carbon.

[0277] In some embodiments, step (f) is performed intentionally or incidentally to generate activated carbon byproducts. If step (f) is performed, step (e) may or may not be performed.

[0278] In certain embodiments, steps (e) and (f) are carried out in an integrated reactor having separate reaction zones for generating a reducing gas in situ and then utilizing the reducing gas or at least a portion thereof to reduce the metal oxide to a metal or a less reduced metal oxide.

[0279] If step (f) is used, at least 1% by weight, 5% by weight, 10% by weight, 20% by weight, 30% by weight, 40% by weight, 50% by weight, 60% by weight, 70% by weight, 80% by weight, or 90% by weight of the bioreagent generated in step (b) can be recovered as activated carbon. The process can be adjusted so that more or less activated carbon is produced compared to the carbon (generally as carbon oxides) directed towards the reducing gas.

[0280] In certain embodiments, the fixed carbon in the bioreagent can be used primarily to produce activated carbon, and the volatile carbon in the bioreagent can be used primarily to produce a reducing gas. For example, at least 50% by weight, at least 90% by weight, or essentially all, of the fixed carbon in the bioreagent produced in step (b) can be recovered as activated carbon in step (f), while at least 50% by weight, at least 90% by weight, or essentially all, of the volatile carbon in the bioreagent produced in step (b) can be directed towards a reducing gas (for example, via a steam reforming reaction of volatile carbon to CO).

[0281] Activated carbon, when produced, can be characterized by an iodine value of, for example, at least about 500, 750, 800, 1000, 1500, or 2000. Activated carbon is activated carbon 14 C / 12 It can be characterized by a renewable carbon content of at least 50%, 60%, 70%, 80%, 90%, or 95%, determined from the measurement of the 1C isotope ratio. In some embodiments, activated carbon is... 14 C / 12 It is characterized as a (fully) renewable activated carbon, as determined by the measurement of its 1C isotope ratio.

[0282] In some systems, the second reactor is configured to continuously or periodically remove activated carbon from the second reactor, for example, by a screw conveyor for removing carbon pellets from the reactor. In these or other embodiments, the second reactor is configured to finally remove activated carbon from the second reactor (i.e., at the end of the reaction time period), either by a screw conveyor or by opening the reactor to recover the activated carbon.

[0283] In some embodiments, the second reactor is configured to optimize the production of different types of activated carbon. For example, reaction conditions (e.g., time, temperature, and water vapor concentration) can be selected for activated carbon products having specific attributes such as iodine value. Different reaction conditions can be selected for different activated carbon products, such as those with higher iodine values. The second reactor can operate in campaign mode to produce one product and then switch to another mode for another product. The first product may be removed continuously or periodically during the first campaign, or before switching the reaction conditions of the second reactor. In general, the second reactor can be optimized for the production of different amounts and characteristics of activated carbon, as well as different amounts and qualities of reducing gas.

[0284] If activated carbon is desired, a third reactor may or may not be present. In some embodiments, both activated carbon and metal products are produced, as shown in Figure 3. In certain embodiments, an integrated reactor is used for both activated carbon production and the reduction of metal oxides to metal products.

[0285] Activated carbon can be characterized by an iodine value of, for example, at least about 500, 750, 1000, 1500, or 2000. Activated carbon is... 14 C / 12 It can be characterized by a renewable carbon content of at least 90%, determined from the measurement of the 1C isotope ratio. In some embodiments, activated carbon is 14 C / 12It is characterized as a (fully) renewable activated carbon, as determined by the measurement of its 1C isotope ratio.

[0286] The activated carbon produced by the processes disclosed herein can be used in many ways.

[0287] In some embodiments, activated carbon is used internally at the process site to purify one or more primary products. In some embodiments, activated carbon is used in-situ to purify water. In these or other embodiments, activated carbon is used in-situ to treat liquid waste streams to reduce liquid phase emissions, or to treat steam waste streams to reduce air emissions. In some embodiments, activated carbon is used as a soil conditioner to aid in the generation of new biomass, which may be the same type of biomass used in-situ as a local raw material.

[0288] Activated carbon prepared according to the processes disclosed herein may have the same or better properties as conventional fossil fuel-based activated carbon. In some embodiments, the activated carbon has a surface area comparable to, equal to, or greater than, that associated with fossil fuel-based activated carbon. In some embodiments, the activated carbon can control contaminants as well as, or better than, that associated with conventional activated carbon products. In some embodiments, the activated carbon has an inert material (e.g., ash) level comparable to, equal to, or less than, that associated with conventional activated carbon products. In some embodiments, the activated carbon has a particle size or particle size distribution comparable to, equal to, greater than, or less than, that associated with conventional activated carbon products. In some embodiments, the activated carbon has a particle shape comparable to, substantially similar to, or the same as, that associated with conventional activated carbon products. In some embodiments, the activated carbon has a particle shape substantially different from that associated with conventional activated carbon products. In some embodiments, the activated carbon has a pore volume comparable to, equal to, or greater than, that associated with conventional activated carbon products. In some embodiments, the activated carbon has pore dimensions comparable to, substantially similar to, or the same as those associated with conventional activated carbon products. In some embodiments, the activated carbon has particle abrasion resistance comparable to, substantially similar to, or the same as those associated with conventional activated carbon products. In some embodiments, the activated carbon has hardness values ​​comparable to, substantially similar to, or the same as those associated with conventional activated carbon products. In some embodiments, the activated carbon has bulk density values ​​comparable to, substantially similar to, or the same as those associated with conventional activated carbon products. In some embodiments, the activated carbon product has adsorption capacity comparable to, substantially similar to, or the same as those associated with conventional activated carbon products.

[0289] Prior to suitability for any product application or actual use, the disclosed activated carbon can be analyzed, measured, and optionally modified (by additives, etc.) in various ways. Some potentially important properties include density, particle size, surface area, microporosity, absorption, adsorption, binding capacity, reactivity, desulfurization activity, basicity, hardness, and iodine value.

[0290] Activated carbon is commercially used in a wide variety of liquid and gas phase applications, including water treatment, air purification, solvent vapor recovery, food and beverage processing, sugar and sweetener refining, automotive applications, and pharmaceuticals. Key product attributes of activated carbon can include particle size, shape, composition, surface area, pore volume, pore dimensions, particle size distribution, carbon surface and interior chemical properties, particle abrasion resistance, hardness, bulk density, and adsorption capacity.

[0291] The bulk density of bio-derived activated carbon can range from approximately 50 g / liter to approximately 650 g / liter.

[0292] The surface area of ​​bio-derived activated carbon can vary widely. An example surface area is approximately 400 m². 2 / g~about 2000m 2 / g or more, for example, about 500m 2 / g, 600m 2 / g, 800m 2 / g, 1000m 2 / g, 1200m 2 / g, 1400m 2 / g, 1600m 2 / g, or 1800m 2 The value is per gram. Surface area generally correlates with adsorption capacity.

[0293] Pore ​​size distribution can be important in determining the final performance of activated carbon. Pore size measurements can include micropore content, mesopore content, and macropore content.

[0294] The iodine value is a parameter used to characterize the performance of activated carbon. The iodine value measures the degree of carbon activation and is a measure of micropore (e.g., 0–20 Å) content. This is an important measurement for liquid-phase applications. Exemplary iodine values ​​of activated carbon products produced by embodiments of this disclosure include the ranges from or between approximately 500, 600, 750, 900, 1000, 1100, 1200, 1300, 1500, 1600, 1750, 1900, 2000, 2100, and 2200. The unit of iodine value is the number of milligrams of iodine per gram of carbon.

[0295] Another pore-related measurement is the Methylene Blue Number, which measures the mesopore content (e.g., 20–500 Å). Exemplary Methylene Blue Numbers for activated carbon products produced by embodiments of this disclosure include ranges from or between approximately 100, 150, 200, 250, 300, 350, 400, 450, and 500. The unit of the Methylene Blue Number is the number of milligrams of methylene blue (methylthioninium chloride) per gram of carbon.

[0296] Another pore-related measurement is the Molasses Number, which measures macropore content (e.g., >500 Å). Exemplary molasses numbers of activated carbon products produced by embodiments of this disclosure include ranges from or between 100, 150, 200, 250, 300, 350, and 400. The unit of the molasses number is milligrams of molasses per gram of carbon.

[0297] Activated carbon can be characterized by its water retention capacity. In various embodiments, the activated carbon products produced by embodiments of this disclosure have a water retention capacity of about 10% to about 300% (weight of water divided by the weight of dry activated carbon) at 25°C, for example, about 50% to about 100%, for example, about 60% to 80%.

[0298] Hardness, or abrasion number, is a measure of the abrasion resistance of activated carbon. It is an indicator of the physical integrity of the activated carbon in withstanding frictional forces and mechanical stresses during handling or use. A certain degree of hardness is desirable, but if the hardness is too high, excessive equipment abrasion may occur. Exemplary abrasion numbers measured according to ASTM D3802 range from about 1% to over 99%, for example, about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 96%, about 97%, about 98%, about 99%, or at least about 99%.

[0299] In some embodiments, the activated carbon is moderately wear-resistant, but an optimal range of hardness can be achieved that does not cause wear and abrasion in the capital equipment handling the activated carbon. This optimal condition is made possible in some embodiments of the present disclosure by selecting raw materials and processing conditions. In some embodiments where downstream use can handle high hardness, the processes of the present disclosure can operate to increase or maximize hardness to produce a biogenic activated carbon product having an abrasion number of about 75%, about 80%, about 85%, about 90%, about 95%, about 96%, about 97%, about 98%, about 99%, or at least about 99%.

[0300] The bio-derived activated carbon provided by this disclosure has a wide range of commercial applications. For example, but not limited to, bio-derived activated carbon can be used in discharge control, water purification, groundwater treatment, wastewater treatment, air stripping applications, PCB removal applications, odor removal applications, soil vapor extraction, manufacturing gas plants, industrial water filtration, industrial fumigation, tanks and process vents, pumps, blowers, filters, pre-filters, mist filters, piping, piping modules, adsorbers, absorbers, and columns.

[0301] In one embodiment, a method using activated carbon to reduce emissions is (a) To provide activated carbon particles comprising a bio-based activated carbon composition recovered from a second reactor disclosed herein, (b) To provide a gas phase exhaust flow containing selected pollutants, (c) To provide an additive selected to assist in the removal of selected contaminants from the gas phase exhaust flow, (d) Introducing activated carbon particles and additives into the gas phase exhaust flow, thereby adsorbing selected pollutants onto the activated carbon particles, and thereby generating pollutant-adsorbing carbon particles in the gas phase exhaust flow, (e) Separating pollutant-adsorbed carbon particles from the gas phase exhaust flow, thereby generating a gas phase exhaust flow with reduced pollutants.

[0302] Additives for bio-based activated carbon compositions may be provided as part of the activated carbon particles. Alternatively or additionally, additives may be introduced directly into the gas phase exhaust flow, fuel bed, or combustion zone. As will be understood by those skilled in the art, other methods of introducing additives directly or indirectly into the gas phase exhaust flow for the removal of selected contaminants are also possible.

[0303] The selected pollutants (in the gas phase exhaust stream) may be metals such as mercury, boron, selenium, arsenic, or any compounds, salts, or mixtures thereof. The selected pollutants may be, for example, hazardous air pollutants, organic compounds (such as VOCs), or non-condensable gases. In some embodiments, the biogenic activated carbon product adsorbs, absorbs, or chemiadsorbs the selected pollutants in greater quantities than comparable amounts of the non-biogenic activated carbon product. In some such embodiments, the selected pollutants are metals, hazardous air pollutants, organic compounds (such as VOCs), non-condensable gases, or any combination thereof. In some embodiments, the selected pollutants include mercury. In some embodiments, the selected pollutants include one or more VOCs. In some embodiments, the biogenic activated carbon contains at least about 1% by weight of hydrogen or at least about 10% by weight of oxygen.

[0304] Hazardous air pollutants are pollutants that cause or may cause cancer or other serious health effects (e.g., reproductive effects or birth defects, or harmful environmental and ecological effects). Section 112 of the amended Clean Air Act is incorporated herein by reference in its entirety. In accordance with Section 112 of the Clean Air Act, the United States Environmental Protection Agency (EPA) is required to control 189 hazardous air pollutants. Any current or future compounds classified as hazardous air pollutants by the EPA are included in the possible selected pollutants in this context.

[0305] Volatile organic compounds (VOCs), some of which are also hazardous air pollutants, are organic chemicals that have a high vapor pressure at normal room temperature. Examples include short-chain alkanes, olefins, alcohols, ketones, and aldehydes. Many VOCs are hazardous to human health or harmful to the environment. The EPA regulates VOCs in air, water, and land. The EPA's definition of VOCs is found in 40 CFR Section 51.100, which is incorporated herein by reference in its entirety.

[0306] Non-condensable gases are gases that do not condense under normal room temperature conditions. Examples of non-condensable gases include, but are not limited to, nitrogen oxides, carbon monoxide, carbon dioxide, hydrogen sulfide, sulfur dioxide, sulfur trioxide, methane, ethane, ethylene, ozone, ammonia, or combinations thereof.

[0307] Multiple contaminants can be removed by the disclosed activated carbon particles. In some embodiments, the contaminant-adsorbing carbon particles contain at least two contaminants, at least three contaminants, or more. The activated carbon disclosed herein can enable the control of multiple contaminants as well as the control of specific target contaminants (e.g., selenium).

[0308] In some embodiments, pollutant-adsorbing carbon particles are treated to regenerate activated carbon particles. In some embodiments, the method includes thermal oxidation of the pollutant-adsorbing carbon particles. The pollutant-adsorbing carbon particles or their regenerated form can be burned to provide energy.

[0309] In some embodiments, additives for activated carbon are selected from acids, bases, salts, metals, metal oxides, metal hydroxides, metal halides, or combinations thereof. In certain embodiments, additives are selected from magnesium, manganese, aluminum, nickel, iron, chromium, silicon, boron, cerium, molybdenum, phosphorus, tungsten, vanadium, iron chloride, iron bromide, magnesium oxide, dolomite, dolomite lime, fluorite, fluorospar, bentonite, calcium oxide, lime, sodium hydroxide, potassium hydroxide, hydrogen bromide, hydrogen chloride, sodium silicate, potassium permanganate, organic acids (e.g., citric acid), or combinations thereof.

[0310] In some embodiments, the gas phase discharge flow originates from metal treatment, such as the processing of high-sulfur-content metal ores.

[0311] In an exemplary embodiment relating to mercury control, activated carbon can be injected upstream (in piping, etc.) of a particulate matter control device such as an electrostatic precipitator or a fabric filter. In some cases, a flue gas desulfurization (dry or wet) system may be located downstream of the activated carbon injection point. The activated carbon can be injected pneumatically as a powder. The injection location can be determined by the existing plant configuration (unless it is a new location) and whether additional downstream particulate matter control equipment will be modified.

[0312] For boilers currently equipped with particulate matter control devices, implementing bio-based activated carbon injection for mercury control may involve (i) injecting powdered activated carbon upstream of the existing particulate matter control device (electrostatic precipitator or fabric filter), (ii) injecting powdered activated carbon downstream of the existing electrostatic precipitator and upstream of the modified fabric filter, or (iii) injecting powdered activated carbon between the electric fields of the electrostatic precipitator. The inclusion of iron or iron-containing compounds can dramatically improve the performance of the electrostatic precipitator for mercury control. Furthermore, the inclusion of iron or iron-containing compounds can separate spent activated carbon solids from other ash, potentially significantly changing end-of-life options.

[0313] In some embodiments, the powdered activated carbon injection approach can be used in combination with existing SO2 control devices. The activated carbon can be injected before or after the SO2 control device, depending on the availability of means for collecting the activated carbon adsorbent downstream of the injection point.

[0314] In some embodiments, the same physical material can be used in multiple processes, either in an integrated manner or in a sequential manner. For example, activated carbon can be introduced at the end of its effective life as a performance material, into a combustion process for energy value, or into a metal manufacturing process that uses carbon but does not require the properties of activated carbon.

[0315] The bio-based activated carbons and principles of this disclosure can be applied to liquid-phase applications, for example, including the processing of water, aqueous streams of varying purities, solvents, liquid fuels, polymers, molten salts, and molten metals. Where intended herein, “liquid phase” includes slurries, suspensions, emulsions, multiphase systems, or any other material having (or being adjusted to have) a quantity of liquid state present.

[0316] In one embodiment, the present disclosure relates to a method of using activated carbon to purify a liquid, (a) To provide activated carbon particles recovered from the second reactor, (b) To provide a liquid containing selected contaminants, (c) To provide an additive selected to assist in the removal of selected contaminants from a liquid, (d) A method is provided which includes contacting a liquid with activated carbon particles and an additive to adsorb selected contaminants onto the activated carbon particles, thereby producing contaminant-adsorbing carbon particles and a contaminant-reducing liquid.

[0317] The additive may be provided as part of the activated carbon particles, or it may be introduced directly into the liquid. In some embodiments, the additive is provided as part of the activated carbon particles and introduced directly into the liquid.

[0318] In some embodiments relating to liquid-phase applications, additives are selected from acids, bases, salts, metals, metal oxides, metal hydroxides, metal halides, or combinations thereof. For example, additives can be selected from magnesium, manganese, aluminum, nickel, iron, chromium, silicon, boron, cerium, molybdenum, phosphorus, tungsten, vanadium, iron chloride, iron bromide, magnesium oxide, dolomite, dolomite lime, fluorite, fluorospar, bentonite, calcium oxide, lime, sodium hydroxide, potassium hydroxide, hydrogen bromide, hydrogen chloride, sodium silicate, potassium permanganate, organic acids (e.g., citric acid), or combinations thereof.

[0319] In some embodiments, the selected contaminants (in the liquid being treated) are metals such as arsenic, boron, selenium, mercury, or any compound, salt, or mixture thereof. In some embodiments, the selected contaminants are organic compounds (such as VOCs), halogens, biological compounds, insecticides, or herbicides. The contaminant-adsorbing carbon particles may contain two, three, or more contaminants. In some embodiments, the activated carbon product adsorbs, absorbs, or chemiadsorbs the selected contaminants in greater quantities than comparable amounts of non-biological activated carbon product. In some such embodiments, the selected contaminants are metals, hazardous air pollutants, organic compounds (such as VOCs), non-condensable gases, or any combination thereof. In some embodiments, the selected contaminants include mercury. In some embodiments, the selected contaminants include one or more VOCs. In some embodiments, the bio-based activated carbon contains at least about 1% by weight of hydrogen or at least about 10% by weight of oxygen.

[0320] The liquid being treated may be aqueous, but this is not essential to the principles of this disclosure. In some embodiments, the liquid is treated with activated carbon particles in a fixed bed. In other embodiments, the liquid is treated with activated carbon particles in a solution or in a moving bed.

[0321] In one embodiment, the present disclosure relates to a method for removing sulfur-containing contaminants from a liquid using a bio-based activated carbon composition, (a) To provide activated carbon particles recovered from the second reactor disclosed herein, (b) To provide a liquid containing a sulfur-containing contaminant, (c) To provide an additive selected to assist in the removal of sulfur-containing contaminants from a liquid, (d) A method is provided which includes contacting a liquid with activated carbon particles and an additive to adsorb or absorb sulfur-containing contaminants onto or into the activated carbon particles.

[0322] In some embodiments, the sulfur-containing contaminant is selected from elemental sulfur, sulfuric acid, sulfurous acid, sulfur dioxide, sulfur trioxide, sulfate anion, bisulfate anion, sulfite anion, bisulfite anion, thiol, sulfide, disulfide, polysulfide, thioether, thioester, thioacetal, sulfoxide, sulfone, thiosulfinate, sulfimide, sulfoximide, sulfondiimine, sulfur halide, thioketone, thioaldehyde, sulfur oxide, thiocarboxylic acid, thioamide, sulfonic acid, sulfinic acid, sulfenic acid, sulfonium, oxosulfonium, sulfuran, persulfuranes, or combinations thereof, salts, or derivatives. For example, the sulfur-containing contaminant may be a sulfate in the form of an anion or salt.

[0323] The liquid may be an aqueous liquid such as water. In some embodiments, the water is wastewater associated with a process selected from metal mining, acidic mine wastewater, mineral treatment, urban sewage treatment, pulp and paper, ethanol, or any other industrial process that can discharge sulfur-containing pollutants in wastewater. The water may also be a natural body of water (or part thereof) such as a lake, river, or stream.

[0324] In one embodiment, the present disclosure is a process for reducing the concentration of sulfates in water, (a) To provide activated carbon particles recovered from the second reactor disclosed herein, (b) To provide the volume or flow of water containing sulfate, (c) To provide an additive selected to assist in the removal of sulfates from water, (d) A process is provided which includes contacting water with activated carbon particles and an additive to adsorb or absorb sulfates onto or into the activated carbon particles.

[0325] In some embodiments, the sulfate is reduced to a concentration of about 50 mg / L or less in water, such as a concentration of about 10 mg / L or less in water. In some embodiments, the sulfate exists mainly in the form of sulfate anions or bisulfate anions. Depending on the pH, the sulfate may also exist in the form of sulfates.

[0326] Water can be drawn from part or all of the wastewater flow. Exemplary wastewater flows may be associated with metal mining, acidic mine drainage, mineral treatment, urban sewage treatment, pulp and paper, ethanol, or any other industrial processes that may discharge sulfur-containing pollutants into the wastewater. The water may be a natural body of water, such as a lake, river, or stream. In some embodiments, the process is carried out continuously. In other embodiments, the process is carried out in batches.

[0327] When water is treated with activated carbon, this can involve water filtration, water osmosis, or direct addition of activated carbon particles to the water (with sedimentation, clarification, etc.). When osmosis is used, activated carbon can be used in several ways, either within the osmosis device or to assist the osmosis device. In some embodiments, activated carbon particles and additives are introduced directly into the water before osmosis. Activated carbon particles and additives are optionally used in pre-filtration before osmosis. In certain embodiments, activated carbon particles and additives are incorporated into a membrane for osmosis.

[0328] This disclosure also relates to a method using a bio-based activated carbon composition to remove sulfur-containing contaminants from the gas phase, (a) To provide activated carbon particles recovered from the second reactor disclosed herein, (b) To provide a gas phase exhaust flow containing sulfur-containing pollutants, (c) To provide an additive selected to assist in the removal of sulfur-containing pollutants from gas phase exhaust flows, (d) Introducing activated carbon particles and additives into the gas phase discharge flow, thereby adsorbing or absorbing sulfur-containing pollutants onto the activated carbon particles, (e) A method is provided which includes separating activated carbon particles from a gas phase discharge stream.

[0329] In some embodiments, the sulfur-containing contaminant is selected from elemental sulfur, sulfuric acid, sulfurous acid, sulfur dioxide, sulfur trioxide, sulfate anion, bisulfate anion, sulfite anion, bisulfite anion, thiol, sulfide, disulfide, polysulfide, thioether, thioester, thioacetal, sulfoxide, sulfone, thiosulfinate, sulfimide, sulfoximide, sulfondiimine, sulfur halide, thioketone, thioaldehyde, sulfur oxide, thiocarboxylic acid, thioamide, sulfonic acid, sulfinic acid, sulfenic acid, sulfonium, oxosulfonium, sulfuran, persulfuranes, or combinations thereof, salts, or derivatives.

[0330] Generally speaking, the disclosed activated carbon can be used in any application where conventional activated carbon may be used. In some embodiments, the activated carbon is used as a whole (i.e., 100%) substitute for conventional activated carbon. In some embodiments, the activated carbon comprises essentially all or substantially all of the activated carbon used for a particular application. In some embodiments, the activated carbon comprises about 1% to about 100% biogenic activated carbon.

[0331] For example, activated carbon can be used in filters, either alone or in combination with conventional activated carbon products. In some embodiments, the packed bed or packed column comprises the disclosed activated carbon. In such embodiments, the bio-derived activated carbon has size characteristics suitable for a particular packed bed or packed column. The injection of bio-derived activated carbon into gas streams may be useful for controlling pollutant emissions in gas or liquid streams originating from coal-fired power plants, biomass power plants, metal processing plants, crude oil refineries, chemical plants, polymer plants, pulp and paper plants, cement plants, waste incinerators, food processing plants, gasification plants, and synthesis gas plants.

[0332] Metal oxide reduction furnace Next, various embodiments using a metal ore furnace or a chemical reduction furnace will be described further.

[0333] A metal ore furnace or chemical reduction furnace may be a blast furnace, direct reduction metal furnace, top gas recirculation blast furnace, shaft furnace, reverberatory furnace, crucible furnace, silenced furnace, retort furnace, flash furnace, Tecnored furnace, Ausmelt furnace, ISASMELT furnace, paddle furnace, bogie hearth furnace, continuous chain furnace, pusher furnace, rotary hearth furnace, walking beam furnace, electric arc furnace, induction furnace, basic oxygen furnace, paddle furnace, Bessemer furnace, or a combination thereof.

[0334] Metal ore furnaces or chemical reduction furnaces can be positioned horizontally, vertically, or at an angle. The flow of solids and fluids (liquids or gases) can be parallel or countercurrent. The solids in the furnace can be in a fixed bed or a fluidized bed. Metal ore furnaces or chemical reduction furnaces can operate under a variety of process conditions of temperature, pressure, and residence time.

[0335] Some variations of this disclosure relate specifically to blast furnaces. A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals such as iron or copper. Blast furnaces are used to smelt iron ore to produce pig iron, an intermediate material used in the production of commercial iron and steel. Blast furnaces are also used in combination with sintering plants, for example, in base metal smelting.

[0336] The term "blast" refers to the forced or supplied combustion air exceeding atmospheric pressure. In a blast furnace, metal ore, carbon (e.g., bioreagents or derivatives thereof, as disclosed herein), and typically flux (e.g., limestone) are continuously supplied through the top of the furnace, while a hot blast of air (optionally with oxygen concentration) is blown into the bottom of the furnace through a series of pipes called tuyeres. Chemical reduction reactions occur throughout the furnace as the material falls downward. The final products are typically the molten metal and slag phases removed from the bottom, as well as the exhaust gas (reduction off-gas) exiting from the top of the furnace. The rising flow of high-temperature CO-concentrated gas and the descending flow of metal ore along the countercurrent-contacting flux enable efficient chemical reactions that reduce the metal ore to metal.

[0337] In air furnaces (such as reverberatory furnaces), the hot gas is usually drawn in naturally by convection in the chimney flue. According to this broad definition, blast furnaces are classified as bloc furnaces for iron, blowing houses for tin, and smelters for lead.

[0338] Blast furnaces remain a vital part of modern iron production. Modern furnaces are highly efficient and include a Cowper stove that preheats the blast air entering with waste heat from the flue gas, and a recovery system that extracts heat from the hot gases exiting the furnace. Blast furnaces are constructed in the form of tall structures lined with refractory bricks, shaped so that the feed material expands as it heats up during its descent and then shrinks in size as melting begins.

[0339] In some embodiments relating to iron production, a bioreagent containing renewable carbon, iron ore (iron oxide), and limestone flux is charged into the top of the blast furnace. The blast furnace can be configured to expel hot, fouled gas with a high carbon monoxide content from the furnace throat, while a bleeder valve can protect the top of the furnace from sudden gas pressure surges. Coarse particles in the exhaust gas can be settled and disposed of, while the gas can flow through a venturi scrubber or an electrostatic precipitator or gas cooler to lower the temperature of the purified gas. A casting chamber at the bottom of the furnace houses equipment for casting liquid iron and slag. Tapholes can be drilled into refractory plugs so that the liquid iron and slag flow down a trough through openings, separating the iron from the slag. Once the pig iron and slag have been tapped, the tapholes can be sealed with refractory clay. Nozzles called tuyeres are used to supply hot air to increase the efficiency of the blast furnace. Hot air is directed into the furnace through cooled tuyeres near the base. The hot air temperature can be, for example, about 900°C to 1300°C (air temperature). The temperature inside the blast furnace can be at least about 2000°C or higher. Other carbonaceous materials or oxygen can also be injected into the furnace at the tuyere level to combine with carbon (from bioreagents), releasing additional energy and increasing the percentage of reducing gas present, which increases productivity.

[0340] A blast furnace operates on the principle of chemical reduction, where carbon monoxide, which has a stronger affinity for oxygen in metal ore (e.g., iron ore) than the corresponding metal, reduces the metal to its elemental form. Unlike bloc furnaces and reverberatory furnaces, in a blast furnace, flue gas comes into direct contact with the ore and metal, diffusing carbon monoxide into the ore and reducing the metal oxide to the elemental metal mixed with carbon. A blast furnace typically operates as a continuous countercurrent exchange process.

[0341] Silica is usually removed from pig iron. Silica reacts with calcium oxide to form silicates, which float on the surface of the molten pig iron as slag. The downward-moving column for the metal ore, flux, carbon, and reaction products must be sufficiently porous for the flue gas to pass through. This requires that the bioreagent carbon particles are large enough to be permeable. Therefore, the bioreagent (which may contain additives) must be strong enough not to be crushed by the weight of the material on top of it. In addition to the physical strength of the carbon, sulfur, phosphorus, and ash can also be reduced.

[0342] Many chemical reactions occur in blast furnaces. These chemical reactions can be understood by referring to hematite (Fe2O3) as the starting metal oxide. This form of iron oxide is common in iron ore processing, either in the initial raw material or as produced in the blast furnace. Other forms of iron ore (e.g., taconite) have iron oxides of varying concentrations (Fe3O4, Fe2O3, FeO, etc.).

[0343] The main overall chemical reactions that produce molten iron in a blast furnace are as follows: Fe2O3 + 3CO → 2Fe + 3CO2 This is an endothermic reaction. This reaction occurs in several steps, the first of which is that preheated blast air blown into the furnace reacts with carbon (e.g., from a bioreagent) to produce carbon monoxide and heat. 2C + O2 → 2CO High-temperature carbon monoxide is a reducing agent for iron ore, reacting with iron oxide to produce molten iron and carbon dioxide. Depending on the temperature of different parts of the furnace (typically highest at the bottom), the iron is reduced in several steps. At the top, where the temperature is usually in the range of 200-700°C, the iron oxide is partially reduced to iron(II,III) oxide, Fe3O4. 3Fe2O3 + CO → 2Fe3O4 + CO2 At a temperature of approximately 850°C, further down in the furnace, iron(II,III) is further reduced to iron(II) oxide (FeO). Fe3O4 + CO → 3FeO + CO2 High-temperature carbon dioxide, unreacted carbon monoxide, and nitrogen from the air pass through the furnace upwards as the fresh feed material moves downwards into the reaction zone. As the material moves downwards, the counterflowing gas preheats the feed packing and decomposes the limestone (if used) into calcium oxide and carbon dioxide. CaCO3 → CaO + CO2 The calcium oxide formed by decomposition reacts with various acidic impurities in the iron (especially silica) to form slag, which is mainly calcium silicate (CaSiO3). SiO2 + CaO → CaSiO3 As FeO moves to higher temperatures, up to 1200°C, it is further reduced to iron metal, and carbon monoxide is again used as a reactant. FeO + CO → Fe + CO2 The carbon dioxide formed in this process can be converted back to carbon monoxide by reacting it with carbon in the reverse Boudoit reaction. C + CO2 → 2CO

[0344] It is important to note that in the chemical reactions described above, the reducing gas is not a product of the in situ within the furnace, but can be introduced directly into the blast furnace, either alternatively or additionally. In these embodiments, the reducing gas can include both hydrogen and carbon monoxide, both of which function to chemically reduce metal oxides.

[0345] Conventional blast furnaces lack hydrogen available to induce the reduction of metal oxides. In this disclosure, hydrogen can be directly injected into the blast furnace. Alternatively or additionally, hydrogen may be available in the bioreagent supplied to the blast furnace if the bioreagent contains hydrogen-associated volatile carbons (e.g., heavy tar components). Hydrogen may induce an additional reduction reaction similar to that described above, but replacing CO with H2. 3Fe2O3 + H2 → 2Fe3O4 + H2O Fe3O4 + 4H2 → 3Fe + 4H2O These reactions occur in parallel with the reduction reaction by CO. Hydrogen can also react with carbon dioxide in the reverse water-gas shift reaction to produce more CO. In certain embodiments, a reducing gas consisting essentially of hydrogen is supplied to the blast furnace.

[0346] Pig iron produced by blast furnaces typically has a relatively high carbon content of about 3-6% by weight. Pig iron can be used to produce cast iron. Pig iron produced by blast furnaces usually undergoes further processing to reduce its carbon and sulfur content and to produce various grades of steel for commercial use. In a further process step called basic oxygen steelmaking, the carbon is oxidized by blowing oxygen onto the liquid pig iron to form crude steel.

[0347] Desulfurization is conventionally performed during the transport of liquid iron to the steel mill by adding calcium oxide, which reacts with iron sulfide contained in pig iron to form calcium sulfide. In some embodiments, desulfurization may also occur in or downstream of the furnace by reacting metal sulfides with CO (in the reducing gas) to form metal and carbonyl sulfide, CSO. In these or other embodiments, desulfurization may also occur in or downstream of the furnace by reacting metal sulfides with H2 (in the reducing gas) to form metal and carbonyl sulfide, H2S.

[0348] Other types of furnaces may utilize other chemical reactions. In the chemical conversion of metal oxides to metals, which uses carbon or reducing gases in the conversion, it will be understood that the carbon may be renewable carbon. This disclosure provides renewable carbon in bioreagents produced by the pyrolysis of biomass. In certain embodiments, some of the carbon utilized in the furnace is not renewable carbon. In various embodiments, the percentage of renewable carbon among the total carbon consumed in a metal ore furnace may range from about 20% to about 100% or any number in between, for example, at least about 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 99%, or 100%.

[0349] In some variations of this disclosure, a Tecnored furnace, or a variation thereof, is utilized. The Tecnored process is based on a low-pressure moving-bed reduction furnace originally developed by Tecnored Desenvolvimento Tecnologico SA in Brazil, which reduces cold-bonded, carbon-containing, self-fluxing, and self-reducing pellets. Reduction is carried out at a typical reduction temperature in a low-profile shaft furnace. The process produces molten iron (e.g., liquid iron) with high efficiency.

[0350] Tecnored technology was developed as a cokeless ironmaking process, thus significantly reducing greenhouse gas emissions in molten iron production and avoiding the investment and operation of environmentally harmful coke ovens. The Tecnored process uses a combination of high-temperature and low-temperature blasting and does not require additional oxygen. It eliminates the need for coke plants, sintering plants, and tonnage oxygen plants. Therefore, this process has much lower operating and investment costs than those of the traditional ironmaking route.

[0351] In this disclosure, the Tecnored process can be adapted for use with bioreagents in various ways. Several embodiments provide cold-bonded self-reducing aggregates (e.g., pellets or briquettes) produced from iron ore powder or iron-containing residues with added bioreagents. Mixed with flux and binder, these materials are aggregated and thermally cured to produce briquettes / pellets with sufficient strength to meet the physical and metallurgical requirements of the Tecnored process. The resulting aggregates are then smelted in a Tecnored furnace. The fuel for the Tecnored furnace may itself be a high-carbon bioreactant.

[0352] By combining particulate iron oxide with a reducing agent within a briquette, the surface area of ​​the oxide in contact with the reducing agent, and therefore the reaction rate, is dramatically increased. Self-reducing briquettes can be designed to contain enough reducing agent to completely reduce the iron-containing raw materials they contain, and optionally, they can also provide slag chemistry using a desired flux. Self-reducing briquettes are cured at low temperatures before being supplied to the furnace. The heat required to drive the reaction within the self-reducing briquettes is provided by a bed of solid fuel, which may also be in the form of briquettes, upon which the self-reducing briquettes are supplied to the furnace.

[0353] The Tecnored furnace has three zones: (i) the upper shaft zone, (ii) the melting zone, and (iii) the lower shaft zone. In the upper shaft zone, solid fuel (e.g., bioreagents) is charged. In this zone, the Boudois reaction (C + CO2 → 2CO) is prevented, saving energy. Post-combustion in this zone of the furnace burns CO, which provides energy for preheating and reduction of the charge. Inside the pellet, the following reactions occur at a very rapid rate. Fe x O y +yCO → xFe + yCO2 yCO2 + yC = 2yCO In the equation, x is at least approximately 1 and at most approximately 5, and y is at least approximately 1 and at most approximately 7.

[0354] In the molten zone, re-oxidation is prevented by the reducing atmosphere in the charge. The melting of the charge occurs under a reducing atmosphere. In the lower shaft zone, solid fuel is charged. The solid fuel may contain or be essentially composed of high-carbon bioreagents. In this zone, further reduction of residual iron oxide, as well as slag formation reactions of gangue material and fuel ash, occur in a liquid state. Superheating of metal and slag droplets also occurs. These superheated metal and slag droplets sink to the hearth of the furnace by gravity and accumulate there.

[0355] This modified Tecnored process utilizes two different inputs of carbon units: a reducing agent and a solid fuel. While the reducing agent is conventionally coal granules, in this disclosure, the reducing agent may include a bioreagent in the form of carbon granules. The bioreagent is added to a mixture that produces self-reducing aggregates (pellets or briquettes). The required amount of carbon granules is determined by the C / F (carbon to ore granule) ratio, which can be selected to achieve complete reduction of metal oxides.

[0356] Solid fuels (bioreagents) do not necessarily have to be in the form of fine powder. For example, solid fuels can be in the form of lumps, such as those approximately 40-80 mm in size, to meet the physical and thermal needs required from the solid fuel in the Tecnored process. The solid fuel is charged through a side feeder (to avoid the endothermic Boudois reaction in the upper shaft) and provides most of the energy required by the process. This energy is generated by the primary blast (C + O2 → CO2) and secondary blast, and the upstream CO produced by the gasification of the solid fuel in the hearth is burned (2CO + O2 → 2CO2).

[0357] In certain exemplary embodiments, the modified Tecnored process involves pelletizing iron ore granules having a size of at most about 140 mesh, bioreagent granules having a size of at most about 200 mesh, and fluxes such as slaked lime having a size of at most about 140 mesh, using cement as a binder. The pellets are hardened and dried at 200°C before being fed into the top of the Tecnored furnace. The total residence time of the charge in the furnace is about 30–40 minutes. The bioreagents in the form of solid fuel with a size ranging from 40 mm to 80 mm are fed into the furnace below the high-temperature pellet area using a side feeder. Hot blast air at about 1150°C is blown in through tuyeres located on the sides of the furnace to provide combustion air for the biocarbon. A small amount of furnace gas is flowed through the side feeder for use in drying and preheating the solid fuel. Cold blast air is blown in at a higher point to promote after-combustion of CO in the upper shaft. The molten iron produced is tapped into a ladle on a ladle trolley, which can tilt the ladle to remove slag. The liquid iron is optionally desulfurized in the ladle, and the slag is scraped into a slag pot. The molten iron may contain approximately 3-5% by weight of carbon.

[0358] Conventionally, external CO or H2 does not play a significant role in self-reduction processes using Tecnored reactors. However, in the context of this disclosure, external H2 or CO (from the reducing gas) plays a role in the above reaction (Fe x O y In the reaction with hydrogen as a reactant (Fe + yCO → xFe + yCO2), or in the reaction with hydrogen as a reactant (Fe x O y In the reaction (+yH2→xFe+yH2O), the entire chemical reaction can be assisted by increasing the rate or conversion of iron oxide. The reduction reaction can be assisted at least on the surface of the pellet or briquette, and possibly within the bulk phase of the pellet or briquette, because of the rapid mass transfer of high-temperature reducing gases. Some embodiments of this disclosure combine a blast furnace configuration with a Tecnored furnace configuration, thereby utilizing self-reducing pellets or briquettes in addition to the use of reducing gases in the furnace.

[0359] As mentioned above, there are numerous possible furnace configurations for processing metal ore. While this specification does not describe in detail all possible conditions and chemical reactions that may occur in all possible furnaces, it will be understood by those skilled in the art that the principles of this disclosure can be applied to essentially any furnace or process that uses carbon at some point in the process of producing metal from metal ore.

[0360] It will be observed that some processes utilize solid carbon, some processes utilize reducing gas, and some processes utilize both solid carbon and reducing gas. The processes provided herein produce both solid carbon (bioreagent) and reducing gas. In some embodiments, only solid bioreagent is used in the metal ore conversion process. In other embodiments, only reducing gas is used in the metal ore conversion process. In yet another embodiment, both solid bioreagent and reducing gas are used in the metal ore conversion process. In these embodiments using both renewable carbon sources, the percentage of total carbon used in metal ore conversion from reducing gas may be about, at least about, or at most about 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, or 100%. Other carbon use may come from pyrolysis off-gas. Alternatively, some or all of the other carbon use may come from conventional carbon inputs such as coal pulverized.

[0361] Pyrolysis process and system Processes and systems suitable for pyrolysis of biomass raw materials to produce carbon-containing bioreagents are described in more detail here. Such processes and systems can be jointly installed at metal ore mining or metal ore processing sites, but the disclosure is not limited to such joint installations.

[0362] "Pyrolysis" and "to pyrolyze" generally refer to the thermal decomposition of carbonaceous materials. In pyrolysis, there is less oxygen present than is required for complete combustion of the material, such as at most about 10%, 5%, 1%, 0.5%, 0.1%, or 0.01% of the oxygen (based on O2 moles) required for complete combustion. In some embodiments, pyrolysis is carried out in the absence of oxygen.

[0363] Exemplary changes that may occur during pyrolysis include: (i) heat transfer from a heat source increases the temperature inside the raw material; (ii) the initiation of the primary pyrolysis reaction at this higher temperature releases volatile substances and forms char; (iii) the flow of high-temperature volatile substances toward the lower-temperature solid results in heat transfer between the high-temperature volatile substances and the lower-temperature un-pyrolysis raw material; (iv) condensation of some of the volatile substances in the lower-temperature portion of the raw material, followed by a secondary reaction that may produce tar; (v) an autocatalytic secondary pyrolysis reaction proceeds while the primary pyrolysis reaction occurs in competition and simultaneously; and (vi) further pyrolysis, reforming, water-gas shift reaction, free radical recombination, or dehydration may also occur, which are functions of residence time, temperature, and pressure profile.

[0364] Pyrolysis can at least partially dehydrate the starting material (e.g., lignocellulosic biomass). In various embodiments, pyrolysis removes at least about 50%, 75%, 90%, 95%, 99%, or more water from the starting material.

[0365] In some embodiments, the multiple reactor zones are designed and operated to optimize carbon yield and product quality from pyrolysis while maintaining flexibility and adjustability to feedstock variations and product requirements.

[0366] In some non-limiting embodiments, temperature and residence time can be selected to achieve a relatively slow pyrolysis chemical reaction. A potential advantage is the substantial preservation of cell walls contained within the biomass structure, meaning the final product can retain some, most, or all of the shape and strength of the starting biomass. To maximize this potential benefit, apparatus can be utilized that does not mechanically break down cell walls or convert biomass particles into fine powder. Specific reactor configurations are considered in accordance with the following process description.

[0367] Furthermore, if the raw material is a crushed or sized material such as wood chips or pellets, it may be desirable to carefully crush or size the raw material. Careful initial processing preserves the strength and cell wall integrity present in the natural raw material source (e.g., wood). This may also be important if the final product should retain some, most, or all of the shape and strength of the starting biomass.

[0368] In some embodiments, the first zone of the pyrolysis reactor is configured to supply biomass (or another carbon-containing raw material) in a manner that does not "shock" the biomass, which would rupture the cell walls and initiate the rapid decomposition of the solid phase into vapor and gas. This first zone can be thought of as gentle pyrolysis.

[0369] In some embodiments, a second zone of the pyrolysis reactor is configured as a primary reaction zone, where preheated biomass undergoes a pyrolysis chemical reaction to release gas and condensable vapors, leaving behind a considerable amount of solid material which is a high-carbon reaction intermediate. The biomass components (mainly cellulose, hemicellulose, and lignin) decompose to produce vapors, which escape by penetrating pores or by creating new nanopores. The latter effect contributes to the creation of porosity and surface area.

[0370] In some embodiments, a third zone of the pyrolysis reactor is configured to receive high-carbon reaction intermediates and cool the solid to some extent. The third zone may be at a lower temperature than the second zone. In the third zone, chemical reactions and mass transfers can be surprisingly complex. Secondary reactions are thought to occur in the third zone without being limited by any particular theory or proposed mechanism. Carbon-containing components in the gas phase may decompose to form additional fixed carbon or be adsorbed onto carbon. Thus, the final carbonaceous material may optionally include additional carbon deposited from the gas phase by the decomposition of organic vapors (e.g., tar) capable of forming carbon, rather than simply being the residue of the solid from which volatile components have been removed in the processing steps.

[0371] Certain embodiments extend the concept of additional carbon formation by including a separate unit in which cooled carbon is subjected to an environment containing carbon-containing species in order to increase the carbon content of the final product. If the temperature of this unit is below the thermal decomposition temperature, the additional carbon is expected to be in the form of adsorbed carbonaceous species rather than additional fixed carbon.

[0372] Numerous options exist regarding intermediate input and output (purge or probe) flows of one or more phases present within any specific zone, various mass and energy recirculation schemes, various additives that can be introduced anywhere in the process, and the tunability of process conditions, including both reaction and separation conditions to adjust the product distribution. Zone-specific input and output flows enable good process monitoring and control, such as through FTIR sampling and dynamic process adjustments.

[0373] Some embodiments do not use fast pyrolysis, and some embodiments do not use slow pyrolysis. Surprisingly, high-quality carbon materials, including compositions with a very high percentage of fixed carbon, can be obtained from the disclosed processes and systems.

[0374] In some embodiments, the thermal decomposition process for producing high-carbon bioreagents is (a) A step of providing a carbon-containing raw material including biomass, (b) Optionally, a step of drying the raw material to remove moisture contained therein, (c) Optionally, a step of degassing the raw material and removing any interstitial oxygen contained in the raw material, (d) A step of thermally decomposing the raw material at a temperature selected from about 250°C to about 700°C for at least 10 minutes in the presence of a substantially inert gas phase, thereby producing a high-temperature thermal decomposition solid, a condensable vapor, and a non-condensable gas, (e) A step of separating condensable vapor and non-condensable gas from a high-temperature pyrolysis solid, (f) A step of cooling a high-temperature pyrolysis solid to produce a cooled pyrolysis solid, (g) The step of recovering a high-carbon bioreagent containing a cooled, pyrolysis solid.

[0375] For the purposes of this disclosure, “biomass” shall be interpreted as any biological material or a mixture of biological and non-biological materials. Basically, biomass contains at least carbon, hydrogen, and oxygen. The methods and apparatus of this disclosure can be adapted to a wide range of materials of various types, sizes, and moisture content.

[0376] Examples of biomass include plants and plant-derived materials, vegetation, agricultural waste, forestry waste, wood waste, paper waste, animal-derived waste, poultry-derived waste, and municipal solid waste. In various embodiments of the biomass utilization disclosure, the biomass raw material may include one or more materials selected from timber harvest residues, softwood chips, hardwood chips, tree branches, tree stumps, wood knots, leaves, bark, sawdust, off-spec papermaking pulp, cellulose, corn, corn stalks and leaves, wheat straw, rice straw, sugarcane bagasse, switchgrass, pampas grass, animal fertilizer, municipal waste, municipal sewage, commercial waste, grape pomace, tonsil shells, pecan shells, coconut shells, coffee sediment, grass pellets, hay pellets, wood pellets, cardboard, paper, carbohydrates, plastics, and cloth. Those skilled in the art will readily understand that the selection of raw materials is virtually unlimited.

[0377] This disclosure can also be used with carbon-containing raw materials other than biomass, such as fossil fuels (e.g., coal or petroleum coke), or any mixture of biomass and fossil fuels (e.g., biomass / coal blends). In some embodiments, the carbon-containing raw material is or includes coal, oil shale, crude oil, asphalt, or solids from crude oil processing (such as petroleum coke). Examples of raw materials include waste tires, recycled plastics, recycled paper, construction waste, demolition waste, and other waste or recycled materials. For clarity, any method, apparatus, or system described herein can be used with any carbonaceous raw material. The carbon-containing raw material may be transported by any known means, such as trucks, trains, ships, barges, tractor trailers, or any other vehicle or means of transport.

[0378] The selection of one or more specific raw materials is generally carried out in a manner that is advantageous to the economic process. Regardless of the selected raw materials, screening may be in place to remove undesirable materials. Raw materials may be optionally dried before processing.

[0379] The raw materials used can be provided or processed in a wide variety of particle sizes or shapes. For example, the supply material may be a fine powder or a mixture of fine and coarse particles. The supply material may be in the form of larger material pieces such as wood chips or other forms of wood (e.g., round, cylindrical, square, etc.). In some embodiments, the supply material includes pellets or other aggregated forms of particles that are pressed together or otherwise bound together with a binder.

[0380] It should be noted that size reduction is a costly and energy-intensive process. Pyrolytically decomposed materials can be sized with significantly less energy input, i.e., it may be preferable to reduce the particle size of the product rather than the raw material. This is an option in this disclosure because the process does not require fine starting material and does not necessarily involve any significant particle size reduction during processing. The ability to process very large raw material pieces is a significant economic advantage of this disclosure. Notably, some market applications of high-carbon products actually require large sizes (e.g., on the order of centimeters), and therefore, in some embodiments, large pieces are supplied, produced, and sold.

[0381] In the context of this disclosure, if it is desirable to produce a final carbonaceous bioreagent having structural integrity such as a cylindrical shape, there are at least two options. First, the material produced from the process can be collected and then further mechanically processed into the desired form. For example, the product can be pressed or pelletized with a binder. A second option is to use a feed material that generally has the desired size or shape for the final product and employ processing steps that do not destroy the basic structure of the feed material. In some embodiments, the feed and the product have similar geometric shapes such as spheres, cylinders, or cubes.

[0382] The ability to maintain the approximate size of the supply material throughout the entire process is beneficial when product strength is critical. Furthermore, it avoids the difficulties and costs associated with pelletizing high-fixed-carbon materials.

[0383] The starting feed material may be provided at a range of moisture levels, as understood. In some embodiments, the feed material may already be sufficiently dry and therefore does not need to be dried further before pyrolysis. It may be desirable to utilize commercially available sources of biomass that typically contain moisture and feed the biomass through a drying step before introducing it into the pyrolysis reactor. However, in some embodiments, dry feedstock can be used.

[0384] In a pyrolysis reactor, it is desirable to provide a relatively low-oxygen environment, such as O2 in the gas phase, at a concentration of approximately, or at most, 10 mol%, 5 mol%, 4 mol%, 3 mol%, 2 mol%, 1.5 mol%, 1 mol%, 0.5 mol%, 0.2 mol%, 0.1 mol%, 0.05 mol%, 0.02 mol%, or 0.01 mol%. Firstly, uncontrolled combustion should be avoided in a pyrolysis reactor for safety reasons. Some total carbon oxidation to CO2 may occur, and the heat released from exothermic oxidation can assist the endothermic pyrolysis chemical reaction. Large amounts of carbon oxidation, including partial oxidation to synthesis gas, reduce the carbon yield to the solid.

[0385] In practice, achieving a strictly oxygen-free environment in a reactor can be difficult. Approaching this limit, in some embodiments, the reactor is substantially free of molecular oxygen in the gas phase. To ensure that there is little to no oxygen in the pyrolysis reactor, it may be preferable to remove air from the feed material before it is introduced into the reactor. Various methods exist for removing or reducing air in the feed material.

[0386] In some embodiments, a degassing unit is used in which the raw material is transported in the presence of another gas that can remove adsorbed oxygen before and after drying and penetrate the pores of the raw material to remove oxygen from the pores. Essentially, any gas having less than 21 volume% O2 can be used with varying effectiveness. In some embodiments, nitrogen is used. In some embodiments, CO or CO2 is used. A mixture such as a mixture of nitrogen and a small amount of oxygen can be used. Water vapor may be present in the degassed gas, but it should be avoided to return a significant amount of moisture to the feed. The effluent from the degassing unit can be purged (to the atmosphere or an exhaust treatment unit) or recycled.

[0387] In principle, the effluent (or a portion thereof) from the degassing unit can be introduced into the pyrolysis reactor itself because the oxygen removed from the solid is highly diluted. In this embodiment, if the reactor is operating in a counterflow configuration, it may be advantageous to introduce the degassed effluent gas into the final zone of the reactor.

[0388] Various types of degassing units can be used. When drying is performed, drying and subsequent degassing can be carried out due to the inefficiency of washing away soluble oxygen from the present moisture. In certain embodiments, the drying and degassing steps may be combined into a single unit, or some amount of degassing may be achieved during drying.

[0389] The optionally dried and optionally degassed feed material is introduced into a pyrolysis reactor or a series or parallel multiple reactor. The feed material can be introduced using any known means, including, for example, a screw feeder or a rock hopper. In some embodiments, the material feeding system incorporates an air knife.

[0390] When a single pyrolysis reactor is used, multiple zones may be present. Multiple zones, such as two, three, four, or more, can allow for separate control of temperature, solid residence time, gas residence time, gas composition, flow pattern, or pressure to adjust the overall process performance.

[0391] References to “zones” should be broadly interpreted to include regions of space within a single physical unit, physically separated units, or any combination thereof. In the case of continuous reactors, zone boundaries may relate to structures such as the presence of flights within the reactor or separate heating elements for providing heat to separate zones. Alternatively or additionally, zone boundaries in continuous reactors may relate to features such as distinct temperatures, fluid flow patterns, solid flow patterns, or degrees of reaction. In single-batch reactors, “zones” are operational regimes in time, not space. Multiple-batch reactors can also be used.

[0392] It will be understood that abrupt transitions from one zone to another are not necessarily present. For example, the boundary between the preheating zone and the pyrolysis zone can be somewhat arbitrary. Some amount of pyrolysis may occur in part of the preheating zone, while some amount of "preheating" may continue in the pyrolysis zone. The temperature profile within the reactor, including the zone boundaries within the reactor, can be continuous.

[0393] Some embodiments utilize a first zone operated under preheating or mild thermal decomposition conditions. The temperature of the first zone can be selected from approximately 150°C to approximately 500°C, for example, approximately 300°C to approximately 400°C. The temperature of the first zone should not be so high that it shocks the biomass material, destroying the cell walls and initiating rapid decomposition of the solid phase into vapor and gas.

[0394] All references to zone temperatures in this specification should be interpreted non-restrictively to include temperatures applicable to the bulk solid, gas phase, or reactor wall (process side) present. It will be understood that temperature gradients exist in each zone both axially and radially, as well as in time (i.e., after startup or due to transient phenomena). Thus, references to zone temperatures may refer to average temperatures or other effective temperatures that may affect the actual kinetics. Temperatures can be measured directly by thermocouples or other temperature probes, or indirectly by other means.

[0395] The second zone, or generally the first pyrolysis zone, operates under pyrolysis or carbonization conditions. The temperature of the second zone can be in the range of about 250°C to about 700°C or any number in between, for example, about, or at least about, or at most about 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, or 650°C. Within this zone, the preheated biomass undergoes pyrolysis chemical reactions, releasing gases and condensable vapors, leaving a considerable amount of solid material as high-carbon reaction intermediates. The biomass components (mainly cellulose, hemicellulose, and lignin) decompose to produce vapors, which escape by permeating through pores or by creating new pores. The preferred temperature depends at least on the residence time in the second zone, as well as the properties of the raw materials and the desired product characteristics.

[0396] A third zone, or cooling zone, is operated to cool the high-carbon reaction intermediate to a range of degrees. At a minimum, the temperature of the third zone should be lower than the temperature of the second zone. The temperature of the third zone can be selected from approximately 100°C to approximately 550°C, for example, approximately 150°C to approximately 350°C.

[0397] Chemical reactions can continue to occur in the cooling zone. While not limited to any particular theory, it is thought that secondary pyrolysis reactions can be initiated in the third zone. Carbon-containing components in the gas phase can condense (due to the decrease in temperature in the third zone). However, the temperature remains high enough to facilitate reactions that can form additional fixed carbon from the condensed liquid (secondary pyrolysis), or at least reactions that can form bonds between adsorbed species and fixed carbon. One exemplary reaction that may occur is the Boudoit reaction for converting carbon monoxide into carbon dioxide and fixed carbon.

[0398] The residence time in a reactor zone can vary. There is an interaction between time and temperature, such that higher temperatures can allow for shorter reaction times for a desired amount of thermal decomposition, and vice versa. In a continuous reactor (zone), the residence time is the volume divided by the volumetric flow rate. In a batch reactor, the residence time is the batch reaction time after heating to the reaction temperature.

[0399] In multiphase reactors, it should be recognized that multiple residence times exist. In this context, each zone has residence times (and residence time distributions) for both the solid and vapor phases. For a given apparatus using multiple zones, at a given throughput, the residence times across the zones are generally coupled on the solid side, but if multiple inlet and outlet ports are used in individual zones, the residence times may not be coupled on the vapor side. The residence times of the solid and vapor phases are not coupled.

[0400] The solid residence time in the preheating zone can be selected from approximately 5 to 60 minutes, for example, 10, 20, 30, 40, or 50 minutes. Depending on the temperature, a sufficient time is desirable to allow the biomass to reach the desired preheating temperature. The type and size of particles, the physical equipment, and the heat transfer rate, which depends on the heating parameters, determine the minimum residence time required to allow the solid to reach the desired preheating temperature. Additional time may be undesirable as it contributes to higher capital costs unless some amount of gradual pyrolysis is intended in the preheating zone.

[0401] The solid residence time in the pyrolysis zone can be selected from approximately 10 to 120 minutes, for example, 20, 30, 40, 50, 60, 70, 80, 90, or 100 minutes. Depending on the pyrolysis temperature in this zone, there should be sufficient time for the necessary heat transfer followed by the carbonization chemical reaction. For times less than approximately 10 minutes, the temperature needs to be very high, such as above 700°C, in order to remove a large amount of non-carbon elements. This temperature promotes rapid pyrolysis and the generation of vapors and gases derived from carbon itself, which should be avoided if the intended product is solid carbon.

[0402] In static systems, there will be equilibrium transformations that can be substantially reached at a given time. If, as in certain embodiments, vapor flows continuously over a solid with continuous removal of volatile substances, the equilibrium constraint can be removed to allow thermal decomposition and defoliation to continue until the reaction rate approaches zero. Longer periods of time do not substantially alter the remaining persistent solid.

[0403] The solid residence time in the cooling zone can be selected from approximately 5 to 60 minutes, for example, 10, 20, 30, 40, or 50 minutes. Depending on the cooling temperature in this zone, there should be sufficient time to cool the carbon solid to the desired temperature. The cooling rate and temperature determine the minimum residence time required to cool the carbon. Additional time may be undesirable unless some amount of secondary pyrolysis is desired.

[0404] As described above, the residence time of the vapor phase can be selected and controlled separately. The vapor residence time in the preheating zone can be selected from approximately 0.1 minutes to approximately 15 minutes, for example, from approximately 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 minutes. The vapor residence time in the pyrolysis zone can be selected from approximately 0.1 minutes to approximately 20 minutes, for example, from approximately 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 minutes. The vapor residence time in the cooling zone can be selected from approximately 0.1 minutes to approximately 15 minutes, for example, from approximately 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 minutes. Shorter vapor residence times promote the rapid removal of volatile substances from the system, while longer vapor residence times promote the reaction between the components in the vapor phase and the solid phase.

[0405] The operating mode of the reactor and the entire system can be continuous, semi-continuous, batch, or any combination or variation thereof. In some embodiments, the reactor is a continuous counterflow reactor in which solids and vapors flow substantially in opposite directions. The reactor can also operate in batch mode, but can operate in simulated counterflow of vapor by, for example, periodically introducing and removing the gas phase from a batch vessel.

[0406] Various flow patterns may be desired or observed. In chemical reactions and simultaneous separations involving multiple phases in a multi-phase reactor zone, the fluid dynamics can become very complex. Solid flows can approach plugged flows (well mixed in the radial dimension), while vapor flows can approach perfectly mixed flows (high-speed transport in both the radial and axial dimensions). Multiple inlet and outlet ports for vapor can contribute to overall mixing.

[0407] The pressure in each zone can be selected and controlled independently. The pressure in each zone can be independently selected from approximately 1 kPa to approximately 3000 kPa, for example, approximately 101.3 kPa (standard atmospheric pressure). Independent zone pressure control is possible when multiple gas inlets and outlets are used, including vacuum ports for extracting gas when zone pressures below atmospheric pressure are desired.

[0408] In some embodiments, the process can conveniently operate at atmospheric pressure. Operating at atmospheric pressure offers many advantages, ranging from mechanical simplicity to improved safety. In certain embodiments, the pyrolysis zone operates at pressures of approximately 90 kPa, 95 kPa, 100 kPa, 101 kPa, 102 kPa, 105 kPa, or 110 kPa (absolute pressure).

[0409] Vacuum operation (e.g., 10–100 kPa) facilitates the rapid removal of volatile substances from the system. Higher pressures (e.g., 100–1000 kPa) may be useful when off-gas is supplied to high-pressure operation. Higher pressures may also be useful to facilitate heat transfer, chemical reactions, or separation.

[0410] The step of separating condensable vapors and non-condensable gases from the high-temperature pyrolysis solids can be carried out in the reactor itself or using a separate separation unit. A substantially inert sweep gas can be introduced into one or more zones. The condensable vapors and non-condensable gases are then carried away from the zones in the sweep gas and exit the reactor.

[0411] The sweeping gas may be, for example, N2, Ar, CO, CO2, H2, H2O, CH4, other light hydrocarbons, or combinations thereof. The sweeping gas can be preheated before introduction, or cooled if obtained from a heat source.

[0412] Sweeping gases more completely remove volatile components by removing them from the system before they can condense or react further. Sweeping gases allow for the removal of volatiles at a higher rate than would be achieved simply by volatilization at a given process temperature. Alternatively, the use of sweeping gases allows for the use of milder temperatures to remove a specific amount of volatiles. The reason sweeping gases improve volatile removal is that the separation mechanism is not simply relative volatility, but rather a separation of the liquid / vapor phase assisted by the sweeping gas. Sweeping gases can reduce the mass transfer limitations of volatilization, as well as the thermodynamic limitations, by continuously depleting a given volatile species, evaporating more volatile species to achieve thermodynamic equilibrium.

[0413] Some embodiments remove a gas full of volatile organic carbon from a subsequent processing step to produce a product with high fixed carbon. If not removed, the volatile carbon may be adsorbed or absorbed onto the pyrolyzed solid, thereby requiring additional energy (cost) to achieve the desired purer form of carbon. It is also hypothesized that rapidly removing the vapor can increase the porosity of the pyrolyzed solid. Higher porosity is desirable for some products.

[0414] In certain embodiments, the sweeping gas, combined with a relatively low process pressure such as atmospheric pressure, provides fast vapor removal without requiring a large amount of inert gas.

[0415] In some embodiments, the sweep gas flows countercurrently with respect to the flow direction of the raw materials. In other embodiments, the sweep gas flows parallel to the flow direction of the raw materials. In some embodiments, the solid flow pattern approaches a plugged flow, while the sweep gas and gas phase flow patterns generally approach a perfectly mixed flow in one or more zones.

[0416] Sweeping can be performed in one or more of the reactor zones. In some embodiments, the sweep gas is introduced into the cooling zone and extracted from the cooling or pyrolysis zone (along with the volatile substances produced). In some embodiments, the sweep gas is introduced into the pyrolysis zone and extracted from the pyrolysis or preheating zone. In some embodiments, the sweep gas is introduced into the preheating zone and extracted from the pyrolysis zone. In these or other embodiments, the sweep gas can be introduced into each of the preheating zone, pyrolysis zone, and cooling zone, and can also be extracted from each of the zones.

[0417] In some embodiments, the one or more zones in which separation is carried out are units physically separated from the reactor. The separation unit or zone can be located between reactor zones, if desired. For example, a separation unit can be placed between a pyrolysis unit and a cooling unit.

[0418] The sweep gas can be introduced continuously, especially when the solid flow is continuous. When the pyrolysis reaction operates as a batch process, the sweep gas can be introduced after a certain amount of time or periodically to remove volatile substances. Even when the pyrolysis reaction operates continuously, the sweep gas can be introduced semi-continuously or periodically, if desired, using suitable valves and controls.

[0419] The volatile substance-containing sweep gas can exit from one or more reactor zones, and if obtained from multiple zones, it can be combined. The resulting gas stream containing various vapors can then be supplied to a thermal oxidation unit for control of air release. Any known thermal oxidation unit can be used. In some embodiments, natural gas and air are supplied to the thermal oxidation unit to reach a temperature sufficient to substantially destroy the volatile substances contained therein.

[0420] The effluent from the thermal oxidation system is a high-temperature gas stream containing water, carbon dioxide, and nitrogen. This effluent can be purged directly into an air discharge if desired. The energy content of the thermal oxidation system effluent can be recovered, for example, in a waste heat recovery unit. The energy content can also be recovered by heat exchange with another flow (such as a sweep gas). The energy content can be utilized by directly or indirectly heating, or assisting in the heating, of units at other points in the process, such as a dryer or reactor. In some embodiments, essentially all of the thermal oxidation system effluent is used for indirect heating (utility side) of a dryer. The thermal oxidation system can use fuels other than natural gas.

[0421] The yield of carbonaceous materials can vary depending on the aforementioned factors, including the type of raw materials and process conditions. In some embodiments, the net yield of solids as a percentage of the starting materials on a dry basis is at least 25%, 30%, 35%, 40%, 45%, 50%, or higher. The remainder is divided between condensable vapors such as terpenes, tars, alcohols, acids, aldehydes, or ketones, and non-condensable gases such as carbon monoxide, hydrogen, carbon dioxide, and methane. The relative amount of condensable vapors compared to non-condensable gases also depends on the process conditions, including the presence of water.

[0422] With respect to carbon balance, in some embodiments, the net yield of carbon as a percentage of the starting carbon in the raw materials is at least 25%, 30%, 40%, 50%, 60%, 65%, 70%, 75%, 80%, or more. For example, in some embodiments, the carbonaceous material contains about 40% to about 70% of the carbon contained in the starting materials. The remaining carbon forms methane, carbon monoxide, carbon dioxide, light hydrocarbons, aromatic compounds, tars, terpenes, alcohols, acids, aldehydes, or ketones to varying degrees.

[0423] In some embodiments, these compounds or parts thereof are combined with carbon-enriched solids to concentrate the carbon and energy content of the product. In these embodiments, part or all of the gas stream obtained from the reactor, containing various vapors, can be at least partially condensed and then passed over cooled pyrolysis solids derived from a cooling zone or separate cooling units. These embodiments are described in more detail below.

[0424] Following the reaction and cooling within the cooling zone (if any), the carbonaceous solid can be introduced into a separate cooling unit. In some embodiments, the solid is recovered and simply cooled slowly. If the carbonaceous solid is reactive or unstable in air, it may be desirable to maintain an inert atmosphere or to rapidly cool the solid to a temperature below 40°C, for example, ambient temperature. In some embodiments, a water quench is used for rapid cooling. In some embodiments, a fluidized bed cooler is used. The term "cooling unit" should be broadly interpreted to include containers, tanks, pipes, or parts thereof.

[0425] In some embodiments, the process further includes operating a cooling unit to cool a warm pyrolysis solid with steam, thereby producing a cold pyrolysis solid and superheated steam, and drying is carried out at least partially using the superheated steam from the cooling unit. Optionally, the cooling unit may operate to first cool the warm pyrolysis solid with steam to a first cooling unit temperature, and then cool it with air to a second cooling unit temperature, the second cooling unit temperature being lower than the first cooling unit temperature and associated with reducing the risk of combustion of the warm pyrolysis solid in the presence of air.

[0426] Following cooling to ambient conditions, the carbonaceous solid can be recovered, stored, transported to another site, shipped to another site, or otherwise disposed of, traded, or sold. The solid can be fed into a unit to reduce its particle size. Various size reduction units, including pulverizers, shredders, grinders, jet mills, pin mills, and ball mills, are known in the art.

[0427] Several other means for screening or separation based on particle size may be included. Grinding, if present, may be upstream or downstream of grinding. Some of the screened material (e.g., large lumps) can be returned to the grinding unit. Small and large particles can be recovered for separate downstream use. In some embodiments, the cooled pyrolysis solid is ground into a fine powder such as fine carbon or activated carbon product.

[0428] Various additives can be introduced throughout the process before, during, or after any step disclosed herein. Additives can be broadly classified as process additives selected to improve process performance, such as carbon yield or thermal decomposition time / temperature, in order to achieve a desired carbon purity, and product additives selected to improve one or more properties of a high-carbon bioreagent or downstream product incorporating the reagent. Certain additives can provide enhanced process and product (bioreagent or bioreagent-containing product) properties.

[0429] Additives may be added before, during, or after any one or more steps of the process, including adding them to the raw material itself at any point before or after harvesting. Additive treatment may be incorporated before, during, or after sizing, drying, or other preparation of the raw material. Additives may be incorporated into or on raw material supply facilities, transport trucks, unloading equipment, storage bins, conveyors (including open or closed conveyors), dryers, process heaters, or any other units. Additives may be added anywhere in the pyrolysis process itself using suitable means for introducing the additives. Additives may also be added after carbonization or grinding, if desired.

[0430] In some embodiments, the additive is selected from metals, metal oxides, metal hydroxides, or combinations thereof. For example, the additive can be selected from, but is not limited to, magnesium, manganese, aluminum, nickel, chromium, silicon, boron, cerium, molybdenum, phosphorus, tungsten, vanadium, iron chloride, iron bromide, magnesium oxide, dolomite, dolomite lime, fluorite, fluorospar, bentonite, calcium oxide, lime, and combinations thereof.

[0431] In some embodiments, the additive is selected from acids, bases, or salts thereof. For example, the additive may be selected from, but is not limited to, sodium hydroxide, potassium hydroxide, magnesium oxide, hydrogen bromide, hydrogen chloride, sodium silicate, potassium permanganate, or a combination thereof.

[0432] In some embodiments, the additive is selected from metal halides. Metal halides are compounds between a metal and a halogen (fluorine, chlorine, bromine, iodine, and astatine). Halogens can form many compounds with metals. Metal halides are generally obtained by direct bonding of a basic metal salt with a hydrohalic acid, or more generally by neutralization. In some embodiments, the additive is selected from iron chloride (FeCl2 or FeCl3), iron bromide (FeBr2 or FeBr3), or their hydrates, and any combination thereof.

[0433] Additives can result in a final product with a higher energy content (energy density). The increase in energy content may result from an increase in total carbon, fixed carbon, volatile carbon, or even hydrogen. Alternatively or additionally, the increase in energy content may result from the removal of non-combustible materials or materials with a lower energy density than carbon. In some embodiments, additives reduce the degree of liquid formation to favor the formation of solids and gases, or to favor the formation of solids.

[0434] Without being limited to any specific hypothesis, additives can chemically modify the starting biomass, or the treated biomass before pyrolysis, to reduce cell wall breakdown for greater strength / integrity. In some embodiments, additives can increase the fixed carbon content of the biomass raw material before pyrolysis.

[0435] Additives can result in bioreagents having improved mechanical properties, such as yield strength, compressive strength, tensile strength, fatigue strength, impact strength, modulus of elasticity, bulk modulus, or shear modulus. Additives can improve mechanical properties simply by their presence (e.g., the additive itself imparts strength to the mixture) or by some transformation occurring within the additive phase or the resulting mixture. For example, reactions such as vitrification may occur within a portion of the bioreagent containing the additive, thereby improving the final strength.

[0436] Chemical additives can be applied to wet or dry biomass raw materials. Additives can be applied as solid powders, sprays, mists, liquids, or vapors. In some embodiments, additives can be introduced by spraying a liquid solution (such as an aqueous solution or solvent) or by immersion in a tank, bottle, bag, or other container.

[0437] In certain embodiments, immersion pretreatment is used, in which the solid raw material is immersed in a bath containing the additive for a time sufficient to allow the additive to permeate the solid feed material, either in a batch or continuous manner.

[0438] In some embodiments, additives applied to the raw materials can reduce the energy required for thermal decomposition or increase the yield of carbonaceous products. In these or other embodiments, additives applied to the raw materials can provide functionality desirable for the intended use of the carbonaceous products.

[0439] Throughput or process capacity can vary widely from small laboratory-scale units to full operation, including any pilot, demonstration, or semi-commercial scale. In various embodiments, process capacity (for raw materials, products, or both) is at least about 1 kg / day, 10 kg / day, 100 kg / day, 1 ton / day (all tonns are metric tons), 10 ton / day, 100 ton / day, 500 ton / day, 1000 ton / day, 2000 ton / day, or more.

[0440] In some embodiments, the generated solid or a portion of the solid may be recycled to the front end of the process, i.e., to a drying or degassing unit, or directly to the reactor. By returning to the front end and passing through the process again, the treated solid may have a higher fixed carbon content. Solids, liquids, and gaseous flows generated or present in the process may be independently recycled and passed on to subsequent steps, or removed / purged from the process at any point.

[0441] In some embodiments, the pyrolyzed material is recovered and then fed into separate units for further pyrolysis to produce a product with higher carbon purity. In some embodiments, the secondary process can be carried out in a simple container, such as a steel drum, through which a heated inert gas (such as heated N2) is passed. Other containers useful for this purpose include process tanks, barrels, bins, totes, sacks, and roll-offs. This secondary sweep gas, containing volatile substances, can be sent, for example, to a thermal oxidation apparatus or returned to the main process reactor. To cool the final product, the solid can be cooled by passing another stream of inert gas, initially at, for example, ambient temperature, through it, and then returned to the inert gas preheating system.

[0442] Some variations of this disclosure are, (a) A feeder configured to introduce carbon-containing raw materials, (b) an optional dryer, which is operably connected to the supply device and configured to remove moisture contained in the carbon-containing raw material, (c) A multizone reactor operably connected to a dryer, comprising a spatially separated cooling zone and a pyrolysis zone operably connected to it, and configured to have an outlet for removing condensable vapors and non-condensable gases from a solid, (d) A solid cooler arranged in operable communication with a multi-zone reactor, (e) A high-carbon bioreagent generation system is used, comprising a high-carbon bioreagent recovery unit operably connected to a solid cooler.

[0443] Some variant forms are, (a) A feeder configured to introduce carbon-containing raw materials, (b) an optional dryer, which is operably connected to the supply device and configured to remove moisture contained in the carbon-containing raw material, (c) an optional preheater, which is operably connected to the dryer and configured to heat or gently thermally decompose the raw material, (d) A pyrolysis reactor configured to be operably connected to a preheater and to pyrolyze the raw materials, (e) A cooler configured to be operably connected to the pyrolysis reactor and configured to cool the pyrolysis solid, (f) A high-carbon bioreagent generation system comprising a high-carbon bioreagent recovery unit operably connected to a cooler, The system utilizes a high-carbon bioreagent generation system that includes a gas outlet for removing condensable vapors and non-condensable gases from a solid.

[0444] The feeding device can be physically integrated with the multi-zone reactor by means of a screw feeding device or auger mechanism for introducing the feed solid into the first reaction zone.

[0445] In some embodiments, the system further comprises a preheating zone operably connected to the pyrolysis zone. Each of the pyrolysis zone, cooling zone, and preheating zone (if it exists) may be located within a single unit or within separate units.

[0446] Optionally, a dryer may be configured as a drying zone within a multi-zone reactor. Optionally, a solid cooler may be located within a multi-zone reactor (i.e., configured as an additional cooling zone or integrated with the main cooling zone).

[0447] The system may include purging means for removing oxygen from the system. For example, the purging means may comprise one or more inlets for introducing a substantially inert gas and one or more outlets for removing the substantially inert gas and replaced oxygen from the system. In some embodiments, the purging means is a degasser operably arranged in communication between the dryer and the multizone reactor.

[0448] A multi-zone reactor can be configured to include at least a first gas inlet and a first gas outlet. The first gas inlet and the first gas outlet can be arranged in communication with different zones or the same zone.

[0449] In some embodiments, the multizone reactor is configured to include a second gas inlet or a second gas outlet. In some embodiments, the multizone reactor is configured to include a third gas inlet or a third gas outlet. In some embodiments, the multizone reactor is configured to include a fourth gas inlet or a fourth gas outlet. In some embodiments, each zone present in the multizone reactor is configured to include a gas inlet and a gas outlet.

[0450] Gas inlets and outlets not only enable the introduction and extraction of steam, but the gas outlet (probe) in particular enables precise process monitoring and control across various stages of the process, including all stages of the process and potentially all stages of the process. Precise process monitoring is expected to lead to improvements in yield and efficiency, both dynamically and over a period of time, when process conditions can be adjusted using operational history.

[0451] In some embodiments, reaction gas probes are positioned to communicate operably with the pyrolysis zones. Such reaction gas probes may be useful for extracting and analyzing gases to determine the degree of reaction, pyrolysis selectivity, or other process monitoring. Based on the measurements, the process can then be controlled or regulated in any number of ways, such as by adjusting the feed rate, the rate of inert gas sweep, the temperature (of one or more zones), the pressure (of one or more zones), additives, etc.

[0452] As intended herein, “monitoring and control” via a reaction gas probe should be interpreted to include any one or more sample extractions via the reaction gas probe, and optionally, if deemed necessary or desirable, process preparation or equipment adjustments based on the measurements using well-known principles of process control (such as feedback, feedforward, proportional-integral-differential logic, etc.).

[0453] Reaction gas probes can be configured to extract gas samples in many ways. For example, the sampling line may have a pressure lower than the pyrolysis reactor pressure, so that when the sampling line is opened, a certain amount of gas can be easily extracted from the pyrolysis zone. The sampling line may be under vacuum, for example, when the pyrolysis zone is close to atmospheric pressure. Reaction gas probes can be associated with one gas output or a part of one (e.g., a line branched off from a gas output line).

[0454] In some embodiments, both the gas input and gas output are utilized as reaction gas probes by periodically introducing an inert gas into the zone and withdrawing the inert gas from the gas output along with the process sample ("sample sweep"). Such configurations can be used in zones that do not have gas inlets / outlets for substantially inert gas for processing, or the reaction gas probes can be associated with separate gas inlets / outlets in addition to the process inlets and outlets. (In embodiments utilizing sample sweep) the sampling inert gas periodically introduced and withdrawn for sampling may differ from the process inert gas, either for reasons of analytical accuracy or for introducing an analytical tracer, as needed.

[0455] For example, the acetic acid concentration in the gas phase of the pyrolysis zone can be measured using a gas probe to extract the sample, which is then analyzed using a suitable technique (gas chromatography, GC, mass spectrometry, MS, GC-MS, or Fourier transform infrared spectroscopy, FTIR, etc.). The CO or CO2 concentration in the gas phase can be measured and used, for example, as an indicator of pyrolysis selectivity for gas / vapor. The terpene concentration in the gas phase can be measured and used, for example, as an indicator of pyrolysis selectivity for liquid.

[0456] In some embodiments, the system further comprises at least one additional gas probe operably connected to a cooling zone, or a drying zone (if present) or a preheating zone (if present).

[0457] Gas probes for cooling zones can be useful, for example, for determining the extent of any additional chemical reactions occurring within the cooling zone. Gas probes in cooling zones can also be useful as independent temperature measurements (in addition to thermocouples placed within the cooling zone, for example). This independent measurement may be a correlation between the cooling temperature and a measured quantity of a particular kind. The correlation may be developed separately or established after a period of process operation.

[0458] A gas probe in the drying zone may be useful for determining the degree of drying, for example, by measuring the moisture content. A gas probe in the preheating zone may be useful for determining the degree of any mild thermal decomposition that occurs, for example.

[0459] In certain embodiments, the cooling zone is configured with a gas inlet, and the pyrolysis zone is configured with a gas outlet to generate a substantially countercurrent flow of the gas phase relative to the solid phase. Alternatively or additionally, the preheating zone (if present) can be configured with a gas outlet to generate a substantially countercurrent flow of the gas phase relative to the solid phase. Alternatively or additionally, the drying zone can be configured with a gas outlet to generate a substantially countercurrent flow.

[0460] One or more pyrolysis reactors can be selected from any suitable reactor configuration capable of carrying out the pyrolysis process. Exemplary reactor configurations include, but are not limited to, fixed-bed reactors, fluidized-bed reactors, jet-bed reactors, augers, ablation reactors, rotating cones, rotating drum kilns, calciners, roasters, moving-bed reactors, transport-bed reactors, ablation reactors, rotating cones, or microwave-assisted pyrolysis reactors.

[0461] In some embodiments in which the auger is used, sand or another heat carrier can be optionally used. For example, the raw materials and sand can be supplied at one end of the screw. The screw mixes the sand and raw materials and carries them through the reactor. The screw can provide good control over the residence time of the raw materials and does not dilute the pyrolysis products with a carrier or fluidizing gas. The sand can be reheated in a separate container.

[0462] In some embodiments where the ablation process is used, the raw material is moved at high speed against the molten iron surface. Ablation of any char formed on the surface can maintain a high heat transfer rate. Such apparatus can prevent dilution of the product. Alternatively, the raw material particles can be suspended in a carrier gas and introduced at high speed through a cyclone with heated walls.

[0463] In some embodiments where a fluidized bed reactor is used, the raw materials can be introduced into a bed of hot sand fluidized by a gas, which is typically a recirculated product gas. The reference to “sand” as used herein also includes similar substantially inert materials such as glass particles and recovered ash particles. The high heat transfer rate from the fluidized sand can result in rapid heating of the raw materials. Some ablation due to friction with the sand particles may occur. Heat is typically supplied by heat exchanger tubes through which the hot combustion gas flows.

[0464] A circulating fluidized bed reactor can be used in which gas, sand, and raw materials move together. Exemplary transport gases include recirculated product gas and combustion gas. The high heat transfer rate from the sand ensures rapid heating of the raw materials, and ablation is expected to be stronger than in a conventional fluidized bed. A separator can be used to separate the product gas from the sand and char particles. The sand particles can be reheated in a fluidized burner vessel and recycled back into the reactor.

[0465] In some embodiments, the multizone reactor is a continuous reactor comprising a raw material inlet, a plurality of spatially separated reaction zones configured to independently control the temperature and mixing within each of the reaction zones, and a carbonaceous solid outlet, wherein one of the reaction zones is configured to have a first gas inlet for introducing a substantially inert gas into the reactor, and another of the reaction zones is configured to have a first gas outlet.

[0466] In various embodiments, the reactor includes at least two, three, four, or more reaction zones. Each reaction zone is arranged in communication with separately adjustable heating means, independently selected from electric heat transfer, vapor heat transfer, hot oil heat transfer, phase change heat transfer, waste heat transfer, or a combination thereof. In some embodiments, the reactor zones are heated by an effluent flow from a thermal oxidation unit, if present. In some embodiments, at least one additional reactor zone is heated by an effluent flow from a thermal oxidation unit, if present.

[0467] The reactor can be configured to separately control the gas phase composition and gas phase residence time of at least two reaction zones, up to all reaction zones present within the reactor.

[0468] The reactor may be equipped with a second gas inlet or a second gas outlet. In some embodiments, the reactor is configured with a gas inlet in each reaction zone. In these or other embodiments, the reactor is configured with a gas outlet in each reaction zone. The reactor may be a parallel-flow or counter-flow reactor.

[0469] In some embodiments, the raw material inlet is provided with a screw or auger feeding mechanism. In some embodiments, the carbonaceous solid outlet is provided with a screw or auger output mechanism.

[0470] Certain embodiments utilize a rotary or oven equipped with a screw feeder. In these embodiments, the reactor is axially rotatable, i.e., rotates around its central axis. The rotational speed affects the solid flow pattern, as well as heat and mass transport. Each reaction zone is configured with flights positioned on its inner wall to provide solid agitation. The flights may be independently adjustable in each reaction zone.

[0471] Other means of stirring the solid, such as augers, screws, or paddle conveyors, can be used. In some embodiments, the reactor includes a single continuous auger positioned throughout each of the reaction zones. In other embodiments, the reactor includes twin-screws positioned throughout each of the reaction zones.

[0472] Some systems are designed with the ability to maintain the approximate size of the feed material throughout the process, i.e., the ability to process biomass raw materials without destroying or significantly damaging their structure. In some embodiments, the pyrolysis zone does not house augers, screws, or rakes, which tend to significantly reduce the size of the feed material being pyrolyzed.

[0473] In some embodiments of the present disclosure, the system further includes a thermal oxidizer operably connected to an outlet from which condensable vapors and non-condensable gases are removed. The thermal oxidizer may be configured to receive separate fuels (such as natural gas) and oxidizers (such as air) in a combustion chamber adapted to burn the fuels and condensable vapors. Certain non-condensable gases, such as CO or CH4, may also be oxidized to CO2.

[0474] When a thermal oxidation device is used, the system may include a heat exchanger positioned between the thermal oxidation device and the dryer, configured to utilize the heat of combustion for the dryer. This embodiment can significantly contribute to the overall energy efficiency of the process.

[0475] In some embodiments, the system further comprises a carbon-enhancing unit operably connected to a solid cooler and configured to combine condensable vapor in at least a partially condensed form with the solid. The carbon-enhancing unit can increase the carbon content of the high-carbon bioreagent obtained from the recovery unit.

[0476] The system may further include separate pyrolysis units adapted to further pyrolyze high-carbon bioreagents to further increase their carbon content. These separate pyrolysis units may be relatively simple containers, units, or devices such as tanks, barrels, bottles, drums, totes, sacks, or roll-offs.

[0477] The entire system may be in a fixed location or distributed across several locations. The system can be constructed using modules that can be easily replicated for actual scaling up. The system can also be constructed using the principle of economic scale, as is well known in process industries.

[0478] Next, we will further describe some variations of solid carbon reinforcement. In some embodiments, the process for producing high-carbon bioreagents is as follows: (a) To provide carbon-containing raw materials including biomass, (b) Optionally, dry the raw materials to remove the moisture contained within them, (c) Optionally, degas the raw material to remove any interstitial oxygen present in the raw material. (d) In the pyrolysis zone, in the presence of a substantially inert gas, the raw material is pyrolyzed for at least 10 minutes at a pyrolysis temperature selected from about 250°C to about 700°C, thereby producing a high-temperature pyrolysis solid, condensable vapor, and non-condensable gas. (e) Separating condensable vapors and non-condensable gases from high-temperature pyrolysis solids, (f) In a cooling zone, in the presence of a substantially inert gas, the high-temperature pyrolysis solid is cooled for at least 5 minutes and at a cooling temperature below the pyrolysis temperature, thereby generating a warm pyrolysis solid. (g) Optionally, cool the warm pyrolysis solid to produce a cold pyrolysis solid. (h) Subsequently, the condensable vapor or non-condensable gas from step (e) is passed through a warm pyrolysis solid or a cold pyrolysis solid to form an enhanced pyrolysis solid with increased carbon content. (i) recovering high-carbon bioreagents including enhanced pyrolysis solids.

[0479] In some embodiments, step (h) includes passing the condensable vapor from step (e) through a warm pyrolysis solid in vapor or condensed form to produce an enhanced pyrolysis solid with increased carbon content. In some embodiments, step (h) includes passing the non-condensable gas from step (e) through a warm pyrolysis solid to produce an enhanced pyrolysis solid with increased carbon content.

[0480] Alternatively or additionally, a vapor or gas may be brought into contact with the cold pyrolysis solid. In some embodiments, step (h) includes passing a condensable vapor from step (e) through the cold pyrolysis solid in vapor or condensed form to produce an enhanced pyrolysis solid with increased carbon content. In some embodiments, step (h) includes passing a non-condensable gas from step (e) through the cold pyrolysis solid to produce an enhanced pyrolysis solid with increased carbon content.

[0481] In certain embodiments, step (h) includes passing substantially all of the condensable vapor from step (e) through a cold pyrolysis solid in vapor or condensed form to produce an enhanced pyrolysis solid with increased carbon content. In certain embodiments, step (h) includes passing substantially all of the non-condensable gas from step (e) through a cold pyrolysis solid to produce an enhanced pyrolysis solid with increased carbon content.

[0482] The process may include various methods for treating or separating steam or gas before using it for carbon strengthening. For example, an intermediate feed stream containing condensable steam and non-condensable gas obtained from step (e) may be supplied to a separation unit configured to produce at least first and second output streams. In certain embodiments, the intermediate feed stream may contain all of the condensable steam, all of the non-condensable gas, or both.

[0483] Separation techniques include or can be used with distillation columns, flash vessels, centrifuges, cyclones, membranes, filters, packed beds, capillary columns, etc. Separation can be based primarily on, for example, distillation, absorption, adsorption, or diffusion, and can utilize differences in vapor pressure, activity, molecular weight, density, viscosity, polarity, chemical functionality, affinity to the stationary phase, and any combination thereof.

[0484] In some embodiments, the first and second output streams are separated from the intermediate feed stream based on their relative volatility. For example, the separation unit may be a distillation column, a flash tank, or a condenser.

[0485] Therefore, in some embodiments, the first output stream contains condensable vapor, and the second output stream contains non-condensable gas. The condensable vapor may include carbon-containing compounds selected from terpenes, alcohols, acids, aldehydes, or ketones. The vapor from pyrolysis may include aromatic compounds such as benzene, toluene, ethylbenzene, and xylene. Heavier aromatic compounds, such as persistent tars, may be present in the vapor. The non-condensable gas may include carbon-containing molecules selected from carbon monoxide, carbon dioxide, or methane.

[0486] In some embodiments, the first and second output streams are intermediate feed streams separated based on their relative polarity. For example, the separation unit may be a stripping column, a packed bed, a chromatography column, or a membrane.

[0487] Therefore, in some embodiments, the first output stream contains a polar compound, and the second output stream contains a nonpolar compound. The polar compound may include a carbon-containing molecule selected from methanol, furfural, or acetic acid. The nonpolar compound may include a carbon-containing molecule selected from carbon monoxide, carbon dioxide, methane, terpenes, and terpene derivatives.

[0488] Step (h) can increase the total carbon content of a high-carbon bioreagent compared to the same process except that it does not include step (h). The degree of increase in carbon content may be, in various embodiments, for example, about 1%, 2%, 5%, 10%, 15%, 25%, or more.

[0489] In some embodiments, step (h) increases the fixed carbon content of the high-carbon bioreagent. In these or other embodiments, step (h) increases the volatile carbon content of the high-carbon bioreagent. The volatile carbon content is the carbon due to volatile substances in the reagent. Volatile substances may be, but are not limited to, aliphatic or aromatic compounds (e.g., terpenes); oxygenated compounds including alcohols, aldehydes, or ketones; and hydrocarbons including various tars. The volatile carbon may remain bound to or adsorbed on the solid under ambient conditions, but is released upon heating before the fixed carbon is oxidized, gasified, or released as vapor.

[0490] Depending on the conditions associated with step (h), some amount of volatile carbon can become fixed carbon (e.g., via Boudois carbon formation from CO). The volatile substances can enter the micropores of the fixed carbon and exist as condensed / adsorbed species, but remain relatively volatile. This residual volatility may be more advantageous for fuel applications compared to product applications requiring high surface area and porosity.

[0491] Step (h) can increase the energy content (i.e., energy density) of the high-carbon bioreagent. The increase in energy content may result from an increase in total carbon, fixed carbon, volatile carbon, or even hydrogen. The degree of increase in energy content may be, in various embodiments, for example, about 1%, 2%, 5%, 10%, 15%, 25%, or even higher.

[0492] Further separation can be used to recover one or more non-condensable gases or condensable vapors for use in the process or further treatment. For example, further treatment may be included to produce purified carbon monoxide or hydrogen.

[0493] As another example, acetic acid can be separated and then reduced to ethanol. The reduction of acetic acid can be achieved, at least partially, using hydrogen derived from the resulting non-condensable gas.

[0494] Condensible vapors can be used for energy in either a process (such as thermal oxidation) or carbon enrichment to increase the carbon content of high-carbon bioreagents. Certain non-condensable gases, such as CO or CH4, can be used for energy in a process or as part of a substantially inert gas for a pyrolysis step. Any combination of the above is also possible.

[0495] A potential advantage of including step (h) is that the gas stream is cleaned and the resulting gas stream is concentrated into CO and CO2. The resulting gas stream can be used for energy recovery, recycled for solid carbon concentration, or used as an inert gas in a reactor. Similarly, by separating the non-condensable gas from the condensable vapor, the CO / CO2 stream can be prepared for use as an inert gas in a reactor system or cooling system, for example.

[0496] Other variations are based on the understanding that the principle of the carbon strengthening step can be applied to any raw material to which carbon addition is desired.

[0497] In some embodiments, a batch or continuous process for producing high-carbon bioreagents is (a) To provide a solid flow containing a carbon-containing material, (b) To provide a gas stream containing a condensable carbon-containing vapor, a non-condensable carbon-containing gas, or a mixture of a condensable carbon-containing vapor and a non-condensable carbon-containing gas, (c) passing a gas flow through a solid flow under suitable conditions to form a carbon-containing product having an increased carbon content relative to the carbon-containing material.

[0498] In some embodiments, the starting carbon-containing material is pyrolytic biomass or roasted biomass. The gaseous flow can be obtained during an integrated process that provides the carbon-containing material. Alternatively, the gaseous flow can be obtained from separate processing of the carbon-containing material. The gaseous flow or a portion thereof can be obtained from an external source (e.g., a sawmill oven). Mixtures of gaseous flows from various sources, as well as mixtures of carbon-containing materials, are possible.

[0499] In some embodiments, the process further includes recirculating or reusing the gas stream to repeat the process and further increase the carbon or energy content of the carbon-containing product. In some embodiments, the process further includes recirculating or reusing the gas stream to carry out the process and increase the carbon or energy content of another raw material different from the carbon-containing material.

[0500] In some embodiments, the process further includes introducing a gas stream into a separation unit configured to produce at least first and second output streams, the gas stream comprising a mixture of condensable carbon-containing vapor and non-condensable carbon-containing gas. The first and second output streams can be separated based on relative volatility, relative polarity, or any other property. The gas streams can be obtained from separate treatments of carbon-containing materials.

[0501] In some embodiments, the process further includes recirculating or reusing the gas stream to repeat the process and further increase the carbon content of the carbon-containing product. In some embodiments, the process further includes recirculating or reusing the gas stream to carry out the process and increase the carbon content of another raw material.

[0502] The carbon-containing product may have an increased total carbon content, a higher fixed carbon content, a higher volatile carbon content, a higher energy content, or any combination thereof, compared to the starting carbon-containing material.

[0503] In related variant forms, the high-carbon bioreagent generation system is (a) A feeder configured to introduce carbon-containing raw materials, (b) an optional dryer, which is operably connected to the supply device and configured to remove moisture contained in the carbon-containing raw material, (c) A multizone reactor operably connected to a dryer, comprising a spatially separated cooling zone and a pyrolysis zone operably connected to it, and configured to have an outlet for removing condensable vapors and non-condensable gases from a solid, (d) A solid cooler arranged in operable communication with a multi-zone reactor, (e) A material concentration unit configured to be operably connected to a solid cooler and to pass condensable vapor or non-condensable gas through a solid to form a reinforced solid with increased carbon content, (f) A high-carbon bioreagent recovery unit is provided which is operably connected to a material concentration unit.

[0504] The system may further include a preheating zone operably connected to the pyrolysis zone. In some embodiments, the dryer is configured as a drying zone within a multi-zone reactor. Each zone may be located within a single unit or separate units. A solid cooler may also be located within the multi-zone reactor.

[0505] In some embodiments, the cooling zone is configured with a gas inlet, and the pyrolysis zone is configured with a gas outlet, thereby generating a substantially countercurrent flow of the gas phase relative to the solid phase. In these or other embodiments, the preheating zone or drying zone (or dryer) is configured with a gas outlet, thereby generating a substantially countercurrent flow of the gas phase relative to the solid phase.

[0506] In certain embodiments, the system incorporates a material concentration unit, and the material concentration unit is (i) A housing having an upper part and a lower part, (ii) an inlet located at the bottom of the lower part of the housing, configured to carry condensable vapor and non-condensable gas, (iii) An outlet at the top of the upper part of the housing, configured to carry a concentrated gas stream derived from condensable vapor and non-condensable gas, (iv) A defined path between the upper and lower parts of the housing, (v) A transport system following a path, the transport system being configured to transport a solid, the housing being shaped so that the solid adsorbs condensable vapor or non-condensable gas.

[0507] This disclosure enables the production of various compositions useful as high-carbon bioreagents and products incorporating such reagents. In some modified forms, high-carbon bioreagents can be produced by any of the processes disclosed herein, for example, (a) A step of providing a carbon-containing raw material including biomass, (b) Optionally, a step of drying the raw material to remove moisture contained therein, (c) Optionally, a step of degassing the raw material and removing any interstitial oxygen contained in the raw material, (d) In a pyrolysis zone, in the presence of a substantially inert gas, the raw material is pyrolyzed for at least 10 minutes at a pyrolysis temperature selected from about 250°C to about 700°C, thereby producing a high-temperature pyrolysis solid, a condensable vapor, and a non-condensable gas; (e) A step of separating condensable vapor and non-condensable gas from a high-temperature pyrolysis solid, (f) In a cooling zone, in the presence of a substantially inert gas, the high-temperature pyrolysis solid is cooled for at least 5 minutes and at a cooling temperature below the pyrolysis temperature to generate a warm pyrolysis solid; (g) A step of cooling a warm pyrolysis solid to produce a cold pyrolysis solid, (h) Produced by a process comprising the step of recovering a high-carbon bioreagent containing a cold pyrolysis solid.

[0508] In some embodiments, the reagent contains at least 70% by weight, at least 80% by weight, at least 90% by weight, or at least 95% by weight of total carbon on a dry basis. The total carbon includes at least fixed carbon and may further include carbon from volatile substances. In some embodiments, the carbon from volatile substances accounts for at least 5%, at least 10%, at least 25%, or at least 50% of the total carbon present in the high-carbon bioreagent. For example, fixed carbon can be measured using ASTM D3172, and volatile carbon can be measured using ASTM D3175.

[0509] High-carbon bioreagents may contain approximately 10% by weight or less of hydrogen on a dry basis, for example, approximately 5% by weight or less. Bioreagents may contain approximately 1% by weight or less of nitrogen on a dry basis, for example, approximately 0.5% by weight or less. Bioreagents may contain approximately 0.5% by weight or less of phosphorus on a dry basis, for example, approximately 0.2% by weight or less. Bioreagents may contain approximately 0.2% by weight or less of sulfur on a dry basis, for example, approximately 0.1% by weight or less.

[0510] Carbon, hydrogen, and nitrogen can be measured, for example, using ASTM D5373 for elemental analysis. Oxygen can be measured, for example, using ASTM D3176. Sulfur can be measured, for example, using ASTM D3177.

[0511] Certain embodiments provide reagents that are substantially carbon plus any ash and present water, and contain little to no hydrogen (except for any moisture that may be present), nitrogen, phosphorus, or sulfur. Accordingly, some embodiments provide bioreagents having less than 100% carbon on a dry / ash-free (DAF) basis.

[0512] Generally speaking, raw materials such as biomass contain non-volatile species, including silica and various metals, that are not readily released during pyrolysis. Of course, it is also possible to use ashless raw materials, in which case substantial amounts of ash should not be present in the pyrolysis solid. Ash can be measured, for example, using ASTM D3174.

[0513] Various amounts of non-combustible materials, such as ash, may be present. High-carbon bioreagents may contain non-combustible materials at a dry basis of about 10% by weight or less, for example, about 5% by weight, about 2% by weight, or about 1% by weight or less. In certain embodiments, the reagent contains little to no ash, or essentially no ash or other non-combustible materials at all. Thus, some embodiments provide essentially pure carbon containing 100% carbon on a dry basis.

[0514] Various amounts of water may be present. On a total mass basis, high-carbon bioreagents may contain at least 1% by weight, 2% by weight, 5% by weight, 10% by weight, 15% by weight, 25% by weight, 35% by weight, 50% by weight, or more of water. Where intended herein, "water" should be interpreted to include any form of water present in the bioreagent, including absorbed water, adsorbed water molecules, chemical hydrates, and physical hydrates. Equilibrium water content may vary depending on at least local environmental factors such as relative humidity. Furthermore, water content may fluctuate during transport, preparation for use, and other logistics. Water content can be measured, for example, using ASTM D3173.

[0515] High-carbon bioreagents can have varying energy content for this purpose, meaning an energy density based on a higher calorific value associated with the total combustion of the oven-dry reagent. For example, high-carbon bioreagents can have an energy content of at least 11,000 Btu / lb, at least 12,000 Btu / lb, at least 13,000 Btu / lb, at least 14,000 Btu / lb, or at least 15,000 Btu / lb. In certain embodiments, the energy content is about 14,000–15,000 Btu / lb. The energy content can be measured, for example, using ASTM D5865.

[0516] High-carbon bioreagents can be formed into powders such as coarse or fine powders. For example, in this embodiment, the reagent can be formed into a powder having an average mesh size of about 200 mesh, about 100 mesh, about 50 mesh, about 10 mesh, about 6 mesh, about 4 mesh, or about 2 mesh.

[0517] In some embodiments, high-carbon bioreagents are formed into structures containing compressed, bound, or aggregated particles. The starting materials for forming these objects may be in powder form of the reagent, such as intermediates obtained by particle size reduction. The objects may be formed by mechanical pressing or other forces, optionally using binders or other means to aggregate the particles together.

[0518] In some embodiments, high-carbon bioreagents are produced in the form of structures whose structure is substantially derived from the raw materials. For example, raw material chips can produce product chips of high-carbon bioreagents. Alternatively, raw material cylinders can produce high-carbon bioreagent cylinders, which can be made somewhat smaller but otherwise maintain the basic structure and geometry of the starting material.

[0519] The high-carbon bioreagents according to this disclosure can be produced or formed into objects having minimum dimensions of at least about 1 cm, 2 cm, 3 cm, 4 cm, 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm or more. In various embodiments, the minimum or maximum dimensions may be length, width, or diameter.

[0520] Other variations of this disclosure relate to the incorporation of additives into a process, a product, or both. In some embodiments, the high-carbon bioreagent includes process additives incorporated during the process. In these or other embodiments, the reagent includes product additives introduced into the reagent after the process.

[0521] In some embodiments, the high-carbon bioreagent is measured on a dry basis. 70% by weight or more total carbon, Hydrogen at a concentration of 5% by weight or less, 1% by weight or less of nitrogen, Phosphorus of 0.5% by weight or less, Sulfur at 0.2% by weight or less, The additive comprises a metal, a metal oxide, a metal hydroxide, a metal halide, or a combination thereof.

[0522] The additives are by no means limited, but can be selected from magnesium, manganese, aluminum, nickel, chromium, silicon, boron, cerium, molybdenum, phosphorus, tungsten, vanadium, iron chloride, iron bromide, magnesium oxide, dolomite, dolomite lime, fluorite, fluorospar, bentonite, calcium oxide, lime, and combinations thereof.

[0523] In some embodiments, the high-carbon bioreagent is measured on a dry basis. 70% by weight or more total carbon, Hydrogen at a concentration of 5% by weight or less, 1% by weight or less of nitrogen, Phosphorus of 0.5% by weight or less, Sulfur at 0.2% by weight or less, It includes an additive selected from acids, bases, or salts thereof.

[0524] The additives are by no means limited, but may be selected from sodium hydroxide, potassium hydroxide, magnesium oxide, hydrogen bromide, hydrogen chloride, sodium silicate, potassium permanganate, or a combination thereof.

[0525] In certain embodiments, the high-carbon bioreagent is measured on a dry basis. 70% by weight or more total carbon, Hydrogen at a concentration of 5% by weight or less, 1% by weight or less of nitrogen, Phosphorus of 0.5% by weight or less, 0.2% by weight or less of sulfur, A first additive selected from metals, metal oxides, metal hydroxides, metal halides, or combinations thereof, A second additive selected from acids, bases, or salts thereof, The first additive is different from the second additive.

[0526] The first additive can be selected from magnesium, manganese, aluminum, nickel, chromium, silicon, boron, cerium, molybdenum, phosphorus, tungsten, vanadium, iron chloride, iron bromide, magnesium oxide, dolomite, dolomite lime, fluorite, fluorospar, bentonite, calcium oxide, lime, or a combination thereof, and the second additive can be independently selected from sodium hydroxide, potassium hydroxide, magnesium oxide, hydrogen bromide, hydrogen chloride, sodium silicate, potassium permanganate, or a combination thereof.

[0527] Certain high-carbon bioreagents essentially consist, on a dry basis, of carbon, hydrogen, nitrogen, phosphorus, sulfur, non-flammable substances, and additives selected from magnesium, manganese, aluminum, nickel, chromium, silicon, boron, cerium, molybdenum, phosphorus, tungsten, vanadium, iron chloride, iron bromide, magnesium oxide, dolomite, dolomite lime, fluorite, fluorospar, bentonite, calcium oxide, lime, or combinations thereof.

[0528] Certain high-carbon bioreagents essentially consist of carbon, hydrogen, nitrogen, phosphorus, sulfur, non-flammable substances, and additives selected from sodium hydroxide, potassium hydroxide, magnesium oxide, hydrogen bromide, hydrogen chloride, sodium silicate, or combinations thereof, on a dry basis.

[0529] The amount of additives (or total additives) can vary widely, including about 0.01% to about 25% by weight, including about 0.1% by weight, about 1% by weight, about 5% by weight, about 10% by weight, or about 20% by weight. Therefore, it will be understood that when relatively large amounts of additives, such as more than about 1% by weight, are incorporated, the energy content calculated based on the total reagent weight (including additives) will decrease. Furthermore, in various embodiments, high-carbon bioreagents with additives can have an energy content of at least about 11,000 Btu / lb, at least 12,000 Btu / lb, at least 13,000 Btu / lb, at least 14,000 Btu / lb, or at least 15,000 Btu / lb.

[0530] The above considerations regarding product form also apply to embodiments that incorporate additives. In fact, certain embodiments incorporate additives as binders, fluxes, or other modifiers to improve the final properties for a particular application.

[0531] In some embodiments, the majority of the carbon contained in high-carbon bioreagents is classified as renewable carbon. In some embodiments, substantially all of the carbon is classified as renewable carbon. Certain market mechanisms (e.g., renewable identification numbers, tax credits, etc.) may exist where value is derived from the renewable carbon content in high-carbon bioreagents.

[0532] In certain embodiments, fixed carbon can be classified as non-renewable carbon (e.g., coal-derived), while volatile carbon, which can be added separately, can be renewable carbon in order to increase not only the energy content but also the renewable carbon value.

[0533] The high-carbon bioreagents produced as described herein are useful for a wide variety of carbonaceous products. These high-carbon bioreagents may themselves be desirable market products. Compared to the latest technologies, the high-carbon bioreagents offered herein are associated with lower levels of impurities, reduced process emissions, and improved sustainability (including a higher renewable carbon content).

[0534] In a modified form, the product may be obtained by the disclosed process or may include any of the high-carbon bioreagents described in the compositions shown herein, or any part, combination, or derivative thereof.

[0535] Generally speaking, high-carbon bioreagents can be burned to generate energy (including electricity and heat), partially oxidized, gasified, or steam reformed to produce synthesis gas, utilized for their adsorption or absorption properties, utilized for their reaction properties in metal refining (such as the reduction of metal oxides as disclosed herein) or other industrial processes, or utilized for their material properties in carbon steel and various other metal alloys. Essentially, high-carbon bioreagents can be used in any market application of carbon-based commodities or advanced materials, including specialized applications to be developed.

[0536] Prior to suitability for any product application or actual use, the disclosed high-carbon bioreagents can be analyzed, measured, and optionally modified (by additives, etc.) in various ways. Some potentially important properties other than chemical composition and energy content include density, particle size, surface area, microporosity, absorption, adsorption, binding capacity, reactivity, desulfurization activity, and basicity.

[0537] Products or materials that can incorporate these high-carbon bioreagents include, but are by no means limited to, carbon-based blast furnace addition products, carbon-based taconite pellet addition products, ladle-added carbon-based products, metcoke carbon-based products, coal substitute products, carbon-based coking products, carbon breeze products, fluidized bed carbon-based raw materials, carbon-based furnace addition products, injectable carbon-based products, fine carbon-based products, stoker carbon-based products, carbon electrodes, or activated carbon products.

[0538] The use of the disclosed high-carbon bioreagents in metal production can reduce slag, increase overall efficiency, and mitigate life-cycle environmental impacts. Therefore, embodiments of this disclosure are particularly suitable for metal processing and production.

[0539] Some variations of this disclosure utilize high-carbon bioreagents as carbon-based blast furnace addition products. A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals such as iron (but not limited to iron). Smelting is a form of extractive metallurgy, whose primary use is to produce metals from ore. Smelting uses heat and chemical reducing agents to decompose the ore. Carbon or carbon monoxide derived from carbon removes oxygen from the ore, leaving the elemental metal.

[0540] The reducing agent may include high-carbon bioreagents, or the reducing agent may consist essentially of high-carbon bioreagents. In a blast furnace, high-carbon bioreagents, ore, and often limestone can be continuously supplied through the top of the furnace, while air (optionally with oxygen concentration) is blown into the bottom of the chamber, resulting in the chemical reaction occurring throughout the furnace as the material moves downward. The final products are typically the molten metal and slag phase removed from the bottom, as well as the flue gas exiting from the top of the furnace. The downward flow of ore in contact with the upward flow of high-temperature carbon monoxide-concentrated gas is a countercurrent process.

[0541] The quality of carbon in a blast furnace is measured by its resistance to degradation. The role of carbon as a permeable medium is crucial for economical blast furnace operation. Carbon decomposition varies depending on its location in the blast furnace and involves a combination of reactions with CO2, H2O, or O2, and abrasion of carbon particles against each other and other components of the input. Decomposed carbon particles can cause clogging and performance degradation.

[0542] The coke reactivity test is a highly regarded measure of the performance of carbon in a blast furnace. This test has two elements: the coke reactivity index (CRI) and the coke strength after reaction (CSR). Carbon-based materials with low CRI values ​​(high reactivity) and high CSR values ​​are preferred for better blast furnace performance. The CRI can be determined in its as-received state according to any suitable method known in the art, for example, by the ASTM method DS341.

[0543] In some embodiments, high-carbon bioreagents provide carbon products with properties suitable for direct introduction into blast furnaces.

[0544] The strength of the high-carbon bioreagent can be determined by any suitable method known in the art, for example, by a drop crushing test or a CSR test. In some embodiments, the high-carbon bioreagent, when blended with another carbon source of optional choice, provides a final carbon product having at least about 50%, 60%, or 70% CSR. The combined product can also provide a final coke product with reactivity suitable for combustion in a blast furnace. In some embodiments, the product has a CRI such that the high-carbon bioreagent is suitable for use as an additive or substitute for methocol, methocoke, powdered coke, foundry coke, or injectable coal.

[0545] In some embodiments, the additive is used in an amount sufficient to provide a high-carbon bioreagent that, when added to another carbon source (e.g., coke) having insufficient CRI or CSR for use in a blast furnace, provides a composite product having sufficient CRI or CSR for use in a blast furnace. In some embodiments, the additive is present in an amount sufficient to provide a high-carbon bioreagent having at most about 40%, 30%, or 20% CRI.

[0546] In some embodiments, additives selected from alkaline earth metals, or their oxides or carbonates, are introduced during or after the process of producing high-carbon bioreagents. For example, calcium, calcium oxide, calcium carbonate, magnesium oxide, or magnesium carbonate can be introduced as additives. By adding these compounds before, during, or after pyrolysis, the reactivity of high-carbon bioreagents in the blast furnace can be increased. These compounds result in stronger materials, i.e., higher CSR, which can improve blast furnace efficiency. In addition, additives such as alkaline earth metals, or those selected from their oxides or carbonates, can result in lower emissions (e.g., SO2).

[0547] In some embodiments, high-carbon bioreagents contain not only a high fixed carbon content, as described above, but also a considerably high proportion of volatile carbon. Volatile substances are expected to have better mass transport to metal oxides at lower temperatures, which can be desirable for metal oxide reduction. Compared to fossil fuel-based products such as coke, high-carbon bioreagents can have sufficient strength and more fixed volatile carbon, which results in greater reactivity.

[0548] In some embodiments, the blast furnace substitute product is a high-carbon bioreagent according to the Disclosure, comprising at least about 55 wt% carbon, at most about 0.5 wt% sulfur, at most about 8 wt% non-combustible material, and a calorific value of at least about 11,000 Btu / pound. In some embodiments, the blast furnace substitute product further comprises at most about 0.035 wt% phosphorus, about 0.5 wt% to about 50 wt% volatile matter, and optionally additives. In some embodiments, the blast furnace substitute product comprises about 2 wt% to about 15 wt% dolomite, about 2 wt% to about 15 wt% dolomite lime, about 2 wt% to about 15 wt% bentonite, or about 2 wt% to about 15 wt% calcium oxide. In some embodiments, the blast furnace substitute product has dimensions substantially in the range of about 1 cm to about 10 cm.

[0549] In some embodiments, the high-carbon bioreagents according to this disclosure are useful as coke substitute products for casting. Coke for casting is generally characterized by having a carbon content of at least about 85% by weight, a sulfur content of about 0.6% by weight, at most about 1.5% by weight of volatile substances, at most about 13% by weight of ash, at most about 8% by weight of moisture, about 0.035% by weight of phosphorus, a CRI value of about 30, and dimensions in the range of about 5 cm to about 25 cm.

[0550] Some variations of this disclosure utilize high-carbon bioreagents as carbon-based taconite pellet addition products. The ores used in the production of iron and steel are iron oxides. Major iron oxide ores include hematite, limonite (also known as braun ore), taconite, and magnetite / black ore. Taconite is a low-grade but important ore and contains both magnetite and hematite. The iron content of taconite is generally 25% to 30% by weight. Blast furnaces require iron-containing ore with at least about 50% by weight for efficient operation. Iron ore can undergo beneficiation, including crushing, screening, tumbling, flotation, and magnetic separation. The refined ore is concentrated to over 60% iron and is often formed into pellets before transport.

[0551] For example, taconite can be ground into a fine powder and combined with a binder such as bentonite clay and limestone. For instance, pellets approximately 1 centimeter in diameter containing about 65% by weight of iron can be formed. The pellets are then calcined to oxidize the magnetite to hematite. The pellets are durable and remain porous enough to allow heated gases to pass through the blast furnace charge and react with the pelletized ore.

[0552] Taconite pellets can be supplied to a blast furnace to produce iron, as described above with respect to blast furnace addition products. In some embodiments, a high-carbon bioreagent is introduced into the blast furnace. In these or other embodiments, the high-carbon bioreagent is incorporated into the taconite pellet itself. For example, beneficiated taconite ore powder can be mixed with a high-carbon bioreagent and a binder, rolled into small objects, and then calcined until hardened. In such embodiments, taconite-carbon pellets with a suitable composition can be conveniently introduced into the blast furnace without requiring a separate carbon source.

[0553] Some variations of this disclosure utilize high-carbon bioreagents as ladle-added carbon products. A ladle is a container used to transport and pour out molten metal. A casting ladle is used to pour molten metal into a mold to produce a casting. A transfer ladle is used to transfer large quantities of molten metal from one process to another. A processing ladle is used for processes that occur within the ladle to alter several aspects of the molten metal, such as the conversion of cast iron to ductile iron by the addition of various elements to the ladle.

[0554] High-carbon bioreagents can be introduced into any type of ladle, but the carbon can be added to the processing ladle in a suitable amount based on the target carbon content. The carbon injected into the ladle may be in the form of a fine powder for good material transport of carbon to the final composition. In some embodiments, the high-carbon bioreagents according to this disclosure, when used as ladle addition products, have a minimum dimension of about 0.5 cm, for example, about 0.75 cm, about 1 cm, about 1.5 cm, or more.

[0555] In some embodiments, the high-carbon bioreagents according to this disclosure are useful, for example, as ladle-added carbon additives in basic oxygen furnace or electric arc furnace facilities where ladle addition of carbon is used (e.g., added to ladle carbon during steelmaking).

[0556] In some embodiments, the ladle-added carbon additive further comprises up to about 5% by weight of manganese, up to about 5% by weight of calcium oxide, or up to about 5% by weight of dolomite lime.

[0557] Direct-reduced iron (DRI), also known as sponge iron, is produced by the direct reduction of iron ore (in the form of lumps, pellets, or powder) using reducing gases conventionally produced from natural gas or coal. The reducing gas can be synthesis gas, which is a mixture of hydrogen and carbon monoxide acting as reducing agents. The high-carbon bioreagents provided herein can be converted into a gaseous stream containing CO to act as reducing agents and produce direct-reduced iron.

[0558] Iron nuggets are a high-quality steelmaking and iron casting supply material. Iron nuggets are essentially all iron and carbon, with little to no gangue (slag) and low levels of metallic residue. They are high-grade pig iron products with excellent transport and handling properties. The carbon contained in the iron nuggets or any part thereof may be high-carbon bioreagents provided herein. Iron nuggets can be produced by reducing iron ore in a rotary hearth furnace using high-carbon bioreagents as a reducing agent and energy source.

[0559] Some variations of this disclosure utilize high-carbon bioreagents as metallurgical coke carbon products. Metallurgical coke, also known as "meth" coke, is a carbon material typically produced by the decomposition distillation of various blends of bituminous coal. The final solid is an unmolten carbon called metallurgical coke. As a result of the loss of volatile gases and partial melting, metcoke has an open, porous form. Metcoke has very low volatility. However, the ash components that were part of the original bituminous coal raw material remain trapped in the resulting coke. Metcoke raw materials are available in a wide range of sizes, from fine powder to basketball-sized chunks. Purity can range from at least about 86% to at most about 92% by weight of fixed carbon.

[0560] Metallurgical coke is used when high-quality, tough, and resilient wear carbon is required. Applications include, but are not limited to, conductive flooring, friction materials (e.g., carbon linings), casting coatings, casting carbon risers, corrosive materials, drilling applications, reducing agents, heat treatment agents, ceramic fillers, electrolytic processes, and oxygen elimination.

[0561] Metcoke can be characterized as having a calorific value of about 10,000 to 14,000 Btu / pound and an ash content of about 10% by weight or more. Accordingly, in some embodiments, the metcoke substitute product includes a high-carbon bioreagent according to the Disclosure comprising at least about 80%, 85%, or 90% by weight of carbon, at most about 0.8% by weight of sulfur, at most about 3% by weight of volatile substances, at most about 15% by weight or less of ash, at most about 13% by weight of water, and at most about 0.035% by weight of phosphorus. When used as a metcoke substitute product, the high-carbon bioreagent according to the Disclosure may have a size range of, for example, about 2 cm to about 15 cm.

[0562] In some embodiments, the metcoke substitute product further includes additives such as chromium, nickel, manganese, magnesium oxide, silicon, aluminum, dolomite, fluorospar, calcium oxide, lime, dolomite lime, bentonite, and combinations thereof.

[0563] Some variations of this disclosure utilize high-carbon bioreagents as coal substitute products. Any process or system using coal can, in principle, be adapted to use high-carbon bioreagents.

[0564] In some embodiments, high-carbon bioreagents are combined with one or more coal-based products to form composite products that have a higher rank than the coal-based products or produce fewer emissions than pure coal-based products when burned.

[0565] For example, low-grade coals such as sub-bituminous coal can be used in applications that normally require high-grade coal products such as bituminous coal by combining them with a selected amount of high-carbon bioreagent according to this disclosure. In other embodiments, the rank of a mixed coal product (e.g., a combination of several coals of different ranks) can be improved by combining the mixed coal with a certain amount of high-carbon bioreagent. The amount of high-carbon bioreagent mixed with the coal product may vary depending on the rank of the coal product, the properties of the high-carbon bioreagent (e.g., carbon content, thermal value, etc.), and the desired rank of the final combined product.

[0566] For example, anthracite is generally characterized by having at least about 80 wt% carbon, about 0.6 wt% sulfur, about 5 wt% volatile matter, up to about 15 wt% ash, up to about 10 wt% water, and a calorific value of about 12,494 Btu / lb. In some embodiments, the anthracite substitute product is a high-carbon bioreagent containing at least about 80 wt% carbon, at most about 0.6 wt% sulfur, at most about 15 wt% ash, and a calorific value of at least about 12,000 Btu / lb.

[0567] In some embodiments, high-carbon bioreagents are useful as thermocoal substitute products. Thermocoal products are generally characterized by high sulfur levels, high phosphorus levels, high ash content, and a calorific value of up to about 15,000 Btu / lb. In some embodiments, the thermocoal substitute product is a high-carbon bioreagent containing at most about 0.5 wt% sulfur, at most about 4 wt% ash, and a calorific value of at least about 12,000 Btu / lb.

[0568] Some variations of this disclosure utilize high-carbon bioreagents as carbon-based coking products. Any coking process or system can be adapted to use high-carbon bioreagents to produce coke or to use them as coke raw materials.

[0569] In some embodiments, high-carbon bioreagents are useful as a substitute for hot coal or coke. For example, a hot coal or coke substitute may essentially consist of a high-carbon bioreagent containing at least about 50% by weight of carbon, at most about 8% by weight of ash, at most about 0.5% by weight of sulfur, and a calorific value of at least about 11,000 Btu / lb. In other embodiments, a hot coke substitute contains a high-carbon bioreagent containing at least about 50% by weight of carbon, at most about 8% by weight of ash, at most about 0.5% by weight of sulfur, and a calorific value of at least about 11,000 Btu / lb. In some embodiments, a hot coke substitute further contains about 0.5% to about 50% by weight of volatile substances. A hot coal or coke substitute may contain about 0.4% to about 15% by weight of water.

[0570] In some embodiments, high-carbon bioreagents are useful as substitute products for petroleum (PET) coke or calcined PET coke. Calcined PET coke is generally characterized by having at least about 66% by weight of carbon, up to 4.6% by weight of sulfur, up to about 5.5% by weight of volatile substances, up to about 19.5% by weight of ash, and up to about 2% by weight of moisture, and may be about 3 mesh or smaller in size. In some embodiments, the calcined PET coke substitute product is a high-carbon bioreagent containing at least about 66% by weight of carbon, at most about 4.6% by weight of sulfur, at most about 19.5% by weight of ash, and at most about 2% by weight of moisture, and is about 3 mesh or smaller in size.

[0571] In some embodiments, high-carbon bioreagents are useful as coking carbon substitutes (e.g., co-calcined with metallurgical coal in a coking furnace). In one embodiment, the coking carbon substitute product is a high-carbon bioreagent containing at least about 55 wt% carbon, at most about 0.5 wt% sulfur, at most about 8 wt% non-combustible material, and at least about 11,000 Btu / pound in calorific value. In some embodiments, the coking carbon substitute product contains about 0.5 wt% to about 50 wt% volatile substances or additives.

[0572] Some variations of this disclosure utilize high-carbon bioreagents as carbon breeze products, which may have very fine particle sizes such as 6 mm, 3 mm, 2 mm, 1 mm, or less. In some embodiments, the high-carbon bioreagents according to this disclosure are useful as powdered coke substitute products. Powdered coke is generally characterized by having a maximum dimension of at most about 6 mm, a carbon content of at least about 80 wt%, 0.6 to 0.8 wt% sulfur, 1 to 20 wt% volatile substances, up to about 13 wt% ash, and up to about 13 wt% moisture. In some embodiments, the powdered coke substitute product is a high-carbon bioreagent according to this disclosure comprising at least about 80 wt% carbon, at most about 0.8 wt% sulfur, at most about 20 wt% volatile substances, at most about 13 wt% ash, at most about 13 wt% moisture, and a maximum dimension of about 6 mm.

[0573] In some embodiments, high-carbon bioreagents are useful as carbon breeze substitute products, for example, during taconite pellet production or in ironmaking processes.

[0574] Several variations utilize high-carbon bioreagents as raw materials for various fluidized beds or as alternative products to carbon-based raw materials for fluidized beds. Carbon can be used in fluidized beds for total combustion, partial oxidation, gasification, steam reforming, etc. Carbon can be converted into synthesis gas for various downstream applications, mainly including the production of energy (e.g., a combination of heat and electricity) or liquid fuels (e.g., methanol or Fischer-Tropsch diesel fuel).

[0575] In some embodiments, the high-carbon bioreagents according to this disclosure are useful, for example, as fluidized bed coal substitute products in fluidized bed furnaces where coal is used (for example, for process heat or energy generation).

[0576] Some variants utilize high-carbon bioreagents as carbon-based furnace addition products. Coal-based carbon furnace addition products are generally characterized by high sulfur levels, high phosphorus levels, and high ash content, which contribute to the degradation of metal products and cause air pollution. In some embodiments, carbon furnace addition alternative products containing high-carbon bioreagents contain at most about 0.5 wt% sulfur, at most about 4 wt% ash, at most about 0.03 wt% phosphorus, and a maximum dimension of about 7.5 cm. In some embodiments, carbon furnace addition alternative products contain about 0.5 wt% to about 50 wt% volatile substances and about 0.4 wt% to about 15 wt% water.

[0577] In some embodiments, high-carbon bioreagents are useful as furnace addition additives in basic oxygen furnaces or electric arc furnace facilities whenever furnace addition carbon is used, for example. For example, furnace addition carbon can be added to scrap steel during steel production in electric arc furnace facilities. In electric arc furnace applications, high-purity carbon is desirable to prevent impurities from being returned to the process after early removal of impurities.

[0578] In some embodiments, the furnace carbon additive is a high-carbon bioreagent containing at least about 80 wt% carbon, at most about 0.5 wt% sulfur, at most about 8 wt% non-combustible material, and at least about 11,000 Btu / pound in calorific value. In some embodiments, the furnace carbon additive further contains up to about 5 wt% manganese, up to about 5 wt% fluorite, about 5 wt% to about 10 wt% dolomite, about 5 wt% to about 10 wt% dolomite lime, or about 5 wt% to about 10 wt% calcium oxide.

[0579] Some variations utilize high-carbon bioreagents as stoker furnace carbon-based products. In some embodiments, the high-carbon bioreagents according to this disclosure are useful, for example, as stoker coal substitute products in stoker furnace facilities where coal is used (e.g., for process heat or energy generation).

[0580] Some variations utilize high-carbon bioreagents as injectable (e.g., fine powder) carbon-based materials. In some embodiments, high-carbon bioreagents are useful as injection-grade calcined PET coke substitute products. Injection-grade calcined PET coke is generally characterized by having at least about 66 wt% carbon, about 0.55 to about 3 wt% sulfur, up to about 5.5 wt% volatile matter, up to about 10 wt% ash, and up to about 2 wt% moisture, and is about 6 mesh or smaller. In some embodiments, the calcined PET coke substitute product is a high-carbon bioreagent containing at least about 66 wt% carbon, at most about 3 wt% sulfur, at most about 10 wt% ash, and at most about 2 wt% moisture, and is about 6 mesh or smaller.

[0581] In some embodiments, high-carbon bioreagents are useful as an injectable carbon substitute product in any application where injectable carbon is used (e.g., injected into slag or ladles during steelmaking), for example in basic oxygen furnace or electric arc furnace facilities.

[0582] In some embodiments, high-carbon bioreagents are useful as pulverized carbon substitute products whenever pulverized carbon is used (for example, for process heat or energy generation). In some embodiments, the pulverized carbon substitute product contains up to about 10 percent calcium oxide.

[0583] Some variations utilize high-carbon bioreagents as carbon addition products for metal formation. In some embodiments, the high-carbon bioreagents according to this disclosure are useful as carbon addition products for the formation of carbon steel or other metal alloys containing carbon. Coal-based late-stage carbon addition products are generally characterized by high sulfur levels, high phosphorus levels, and high ash content, as well as high mercury levels that degrade metallic quality and contribute to air pollution. In some embodiments of this disclosure, the carbon addition product includes at most about 0.5 wt% sulfur, at most about 4 wt% ash, at most about 0.03 wt% phosphorus, a minimum dimension of about 1 to 5 mm, and a maximum dimension of about 8 to 12 mm.

[0584] Some variations utilize high-carbon bioreagents within carbon electrodes. In some embodiments, high-carbon bioreagents are useful as electrode (e.g., anode) materials suitable for use, for example, in aluminum production.

[0585] Other applications of high-carbon bioreagents in carbon electrodes include batteries, fuel cells, capacitors, and other energy storage or energy delivery devices. For example, in lithium-ion batteries, high-carbon bioreagents can be used on the anode side to intercalate lithium. In these applications, carbon purity and low ash content can be very important.

[0586] Some variations of this disclosure utilize high-carbon bioreagents as catalyst supports. Carbon is a known catalyst support in a wide range of catalytic chemical reactions, such as the synthesis of mixed alcohols from synthesis gas using a cobalt-molybdenum sulfide metal catalyst supported on a carbon phase, or iron-based catalysts supported on carbon for the Fischer-Tropsch synthesis of higher hydrocarbons from synthesis gas.

[0587] Several variations utilize high-carbon bioreagents as activated carbon products. Activated carbon is used in a wide variety of liquid-phase and gas-phase applications, including water treatment, air purification, solvent vapor recovery, food and beverage processing, and pharmaceuticals. For activated carbon, the porosity and surface area of ​​the material are generally important. The high-carbon bioreagents provided herein can provide superior activated carbon products in various embodiments due to (i) a larger surface area than fossil fuel-based activated carbon; (ii) carbon renewable potential; (iii) the vascularity of biomass raw materials used in combination with additives, which allows for better penetration / distribution of additives that enhance pollutant control; and (iv) less inert material (ash) resulting in greater reactivity.

[0588] In the above description of market applications for high-carbon bioreagents, it should be recognized that the applications described are neither exclusive nor exhaustive. Therefore, a high-carbon bioreagent described as suitable for one type of carbon product may, in various embodiments, be suitable for any other application described. These applications are illustrative, and there are other applications for high-carbon bioreagents.

[0589] In addition, in some embodiments, the same physical material can be used in multiple market processes, either in an integrated manner or in a sequential manner. Therefore, for example, a high-carbon bioreagent used as a carbon electrode or activated carbon can, at the end of its effective life as a performance material, be introduced into a combustion process or a metalworking process (e.g., reduction of metal ore) for energy value.

[0590] In some embodiments, the bioreagent can be used due to its reactivity / adsorption properties and also as a fuel. For example, a bioreagent injected into an exhaust flow may be suitable for removing pollutants, and then burning the bioreagent particles and possibly the pollutants to generate energy, thermally destroying or chemically oxidizing the pollutants.

[0591] Compared to conventional fossil fuel-based products, high-carbon bioreagents can offer significant environmental and product usage advantages. High-carbon bioreagents may not only be environmentally superior, but also functionally superior from a processing standpoint, for example, due to their higher purity.

[0592] Regarding some embodiments of metal production, the production of bioreagents by the disclosed process is compared to the coking of coal-based products required to prepare them for use in metal production, with CO, CO2, NO x This can result in significantly lower emissions of SO2 and hazardous air pollutants.

[0593] Using high-carbon bioreagents instead of coal or coke also significantly reduces environmental emissions of SO2, hazardous air pollutants, and mercury.

[0594] Furthermore, due to the purity (including low ash content) of these high-carbon bioreagents, the disclosed bioreagents have the potential to reduce slag and increase production capacity in batch metal fabrication processes.

[0595] Modified forms utilizing coal and other non-biomass raw materials The most significantly beneficial environmental impacts occur when the pyrolysis feedstock is exclusively biomass; however, the processes and systems described herein can be adapted to non-biomass feedstocks or mixtures of biomass and other feedstocks. It will be further recognized that in some cases, the pyrolysis step may not be necessary, for example, if the selected solid feedstock (e.g., coal) has sufficient properties such as carbon content or reactivity, or if the feedstock has been pre-pyrolyzed.

[0596] For example, solid carbonaceous raw materials can be selected from biomass, lignite, coal, coal-like carbon deposits, oil shale, asphalt, petroleum coke, waste tires, recycled plastics, recycled paper, construction waste, demolition waste, or a combination thereof.

[0597] If the solid carbonaceous raw material is biomass, or contains biomass, the biomass raw material may be softwood chips, hardwood chips, timber harvest residues, tree branches, tree stumps, leaves, bark, sawdust, corn, corn stalks and leaves, wheat, wheat straw, rice, rice straw, sugarcane, sugarcane bagasse, sugarcane straw, energy sugarcane, sugar beet, sugar beet pulp, sunflower, sorghum, canola, algae, Japanese pampas grass, alfalfa, switchgrass. The following can be selected: fruits, fruit shells, fruit stems, fruit peels, fruit seeds, vegetables, vegetable shells, vegetable stems, vegetable peels, vegetable seeds, grape pomace, tonsil shells, pecan shells, coconut shells, coffee grounds, food waste, commercial waste, grass pellets, hay pellets, wood pellets, cardboard, paper, paper pulp, paper packaging, paper trimmings, food packaging, construction or demolition waste, railway ties, lignin, animal manure, municipal solid waste, municipal sewage, or a combination thereof.

[0598] Please note that "solid carbonaceous raw materials" means that the raw material is substantially in a solid form, but may contain liquids such as water, oil, low molecular weight lignin, tar, and hydrocarbons.

[0599] In some embodiments, the solid carbonaceous raw material is a mixture of biomass and coal, for example, a mixture of about 1% to about 99% biomass and the remainder coal. In certain embodiments, the solid carbonaceous raw material is coal.

[0600] Some variant forms are, (a) To provide a solid carbonaceous raw material, (b) Thermally decomposing a solid carbonaceous raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas, (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting the reagent with the selected reactant to generate a reducing gas, (e) Optionally, chemically reduce the selected metal oxide in the presence of the reducing gas from step (d) to produce the reduced form of the selected metal oxide. (f) A process is provided which optionally includes recovering a reagent continuously or periodically during step (d) or finally after step (d), wherein the recovered reagent is activated carbon.

[0601] Some variant forms are, (a) To provide a solid carbonaceous raw material, (b) Optionally, thermally decompose a solid carbonaceous raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas. (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting the reagent with the selected reactant to generate a reducing gas, (e) Chemically reduce the selected metal oxide in the presence of the reducing gas from step (d), thereby producing the reduced form of the selected metal oxide. (f) A process is provided which optionally includes recovering a reagent continuously or periodically during step (d) or finally after step (d), wherein the recovered reagent is activated carbon.

[0602] Step (b) is often performed when the solid carbonaceous feedstock is a mixture of biomass and coal. When the solid carbonaceous feedstock is coal, step (b) is often omitted unless the coal is lignite or other lower-grade coal that improves the suitability for downstream processing through pyrolysis.

[0603] Some variant forms are, (a) To provide a solid carbonaceous raw material, (b) Optionally, thermally decompose a solid carbonaceous raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas. (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting the reagent with the selected reactant to generate a reducing gas, (e) Optionally, chemically reduce the selected metal oxide in the presence of the reducing gas from step (d) to produce the reduced form of the selected metal oxide. (f) A process comprising recovering a reagent continuously or periodically during step (d), or finally after step (d), wherein the recovered reagent is activated carbon.

[0604] Some variant forms are, A first reactor configured to thermally decompose a solid carbonaceous raw material, thereby producing a bioreagent containing carbon and a thermal decomposition off-gas, A second reactor configured to react a reagent with a selected reactant to generate a reducing gas, and optionally a second reactor configured to continuously, periodically, or finally remove activated carbon from the second reactor, The system comprises a third reactor configured to optionally chemically reduce a selected metal oxide in the presence of a reducing gas, thereby producing a reduced form of the selected metal oxide, The system is provided, optionally comprising one or more heating units that are thermally connected to a first reactor, a second reactor, or (if present) a third reactor, wherein one or more heating units are configured to oxidize a pyrolysis off-gas, thereby generating heat.

[0605] Some variant forms (a) To provide a solid carbonaceous raw material, (b) Optionally, thermally decompose a solid carbonaceous raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas. (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting the reagent with the selected reactant to generate a reducing gas, (e) Chemically reduce the selected metal oxide in the presence of the reducing gas from step (d), thereby producing the reduced form of the selected metal oxide. (f) Recovery of metal products including the reduced form of the selected metal oxide, (g) optionally recovering a reagent continuously or periodically during step (d), or finally after step (d), wherein the recovered reagent is activated carbon, and the metal product produced by the process is provided.

[0606] Some variant forms are, (a) To provide a solid carbonaceous raw material, (b) Optionally, thermally decompose a solid carbonaceous raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas. (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting the reagent with the selected reactant to generate a reducing gas, (e) Separating hydrogen from a reducing gas, wherein the hydrogen is optionally separated by one or more separation techniques selected from pressure swing adsorption, molecular sieve membrane separation, or cryogenic distillation. (f) Recovering renewable hydrogen products containing hydrogen, (g) optionally recovering a reagent continuously or periodically during step (d) or finally after step (d), wherein the recovered reagent is activated carbon, and the process provides a renewable hydrogen product produced by the process.

[0607] Some variant forms are, (a) To provide a solid carbonaceous raw material, (b) Optionally, thermally decompose a solid carbonaceous raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas. (c) Optionally, oxidize the pyrolysis off-gas to generate heat, (d) Reacting the reagent with the selected reactant to generate a reducing gas, (e) Optionally, chemically reduce the selected metal oxide in the presence of the reducing gas from step (d) to produce the reduced form of the selected metal oxide. (f) The present invention provides an activated carbon product produced by a process comprising recovering a reagent continuously or periodically during step (d), or finally after step (d), wherein the recovered reagent is activated carbon.

[0608] This detailed description refers to several embodiments of the Disclosure and non-limiting examples of how the Disclosure may be understood and implemented. Other embodiments may be utilized without departing from the spirit and scope of the Disclosure and without providing all of the features and benefits described herein. The Disclosure incorporates routine experimentation and optimization of the methods and systems described herein. Such modifications and variations shall be deemed to be within the scope of the Disclosure as defined by the claims.

[0609] All publications, patents, and patent applications referenced herein are incorporated herein by whole by reference as if each publication, patent, or patent application were specifically and individually described herein.

[0610] Where the methods and steps described above describe specific events occurring in a particular order, those skilled in the art will recognize that the order of the specific events can be changed, and such changes will constitute variations of the present disclosure. Furthermore, some of the steps may be performed sequentially, or simultaneously in a parallel process, if possible.

[0611] Therefore, to the extent that such variations of the Disclosure exist that are within the scope of the intent of the Disclosure or equivalents of the Disclosure found in the attached claims, the Patent is intended to encompass those variations as well. The Disclosure shall be limited solely by the claims. [Examples]

[0612] Example 1: Reduction of iron ore using reducing gas derived from a bioreagent. Douglas fir (Pseudotsuga menziesii) in the form of wood chips is provided as biomass raw material. The average size of the wood chips is approximately 25 mm in length, 25 mm in width, and 5 mm in thickness.

[0613] Powdered iron ore is supplied in the form of taconite. Taconite is a low-grade silicate iron ore containing 20-30% by weight of magnetite (Fe3O4). Taconite is mainly mined in the Mesabi Iron Range in Minnesota, USA, and the Marquette Iron Range in Michigan, USA.

[0614] The biomass raw material is pyrolysis in a continuous pyrolysis reactor at a pyrolysis temperature of approximately 600°C and a pyrolysis residence time of approximately 30 minutes. The pyrolysis pressure is approximately 1 bar (atmospheric pressure) under an inert gas consisting essentially of N2. There is a solid output and a vapor output from the pyrolysis reactor. The solid output is a bioreagent containing carbon. The vapor output i...

Claims

1. A process for producing a metal product, wherein the process is (a) To provide biomass raw materials, (b) Thermally decomposing the biomass raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas, (c) Oxidizing the pyrolysis off-gas and thereby generating heat, (d) Reacting the bioreagent with a selected reactant to generate a reducing gas, (e) Chemically reduce the selected metal oxide in the presence of the reducing gas from step (d), thereby producing the reduced form of the selected metal oxide, (f) Recovering the metal product including the reduced form of the selected metal oxide, (g) The process comprising recovering the bioreagent continuously or periodically during step (d), or finally after step (d), thereby producing a recovered bioreagent which is activated carbon.

2. The process according to claim 1, wherein the selected reactant in step (d) is water.

3. The process according to claim 1, wherein the selected reactant in step (d) is oxygen, and the oxygen is included in air, pure oxygen, concentrated oxygen, ozone, or a combination thereof.

4. The process according to claim 1, wherein the reducing gas contains at least 10 mol% hydrogen.

5. The process according to claim 1, wherein the reducing gas contains at least 10 mol% carbon monoxide.

6. The process according to claim 1, further comprising increasing the hydrogen content of the reducing gas via a water-gas shift reaction.

7. A process for producing renewable hydrogen products, wherein the process is (a) To provide biomass raw materials, (b) Thermally decomposing the biomass raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas, (c) Oxidizing the pyrolysis off-gas and thereby generating heat, (d) Reacting the bioreagent with a selected reactant to generate a reducing gas, (e) Separating hydrogen from the reducing gas, which is achieved using pressure swing adsorption, molecular sieve membrane separation, or cryogenic distillation, (f) Recovering a renewable hydrogen product containing the hydrogen, wherein the hydrogen is a hydrogen isotope ２ H / １ According to H analysis, the recovered hydrogen is characterized as at least 50% renewable hydrogen. (g) The process comprising recovering the bioreagent continuously or periodically during step (d), or finally after step (d), thereby producing a recovered bioreagent which is activated carbon.

8. The process according to claim 7, wherein the selected reactant in step (d) is water.

9. The process according to claim 7, wherein the selected reactant in step (d) is oxygen, and the oxygen is air, pure oxygen, concentrated oxygen, ozone, or a combination thereof.

10. The process according to any one of claims 7 to 9, wherein the reducing gas contains at least 10 mol% hydrogen.

11. The process according to any one of claims 7 to 10, wherein the reducing gas comprises at least 10 mol% carbon monoxide.

12. The process according to claim 7, further comprising increasing the hydrogen content of the reducing gas via a water-gas shift reaction.

13. The process according to claim 7, wherein the renewable hydrogen product contains at least 50 mol% hydrogen.

14. The hydrogen is characterized as fully renewable hydrogen, and the residual carbon contained in the renewable hydrogen product is １４ C / １２ The process according to claim 7, wherein the carbon is essentially completely renewable, as determined by the measurement of the carbon isotope ratio.

15. The process according to claim 7, wherein the renewable hydrogen product is substantially nitrogen-free.

16. A process for producing activated carbon products, wherein the process is (a) To provide biomass raw materials, (b) Thermally decomposing the biomass raw material to produce a bioreagent containing carbon and a thermal decomposition off-gas, (c) Oxidizing the pyrolysis off-gas and thereby generating heat, (d) Reacting the bioreagent with a selected reactant to generate a reducing gas, (e) Chemically reduce the selected metal oxide in the presence of the reducing gas from step (d), thereby producing the reduced form of the selected metal oxide, (f) Continuously or periodically during step (d), or finally after step (d), to produce a recovered bioreagent which is activated carbon, wherein the bioreagent contains at least 50% by weight of fixed carbon, and the activated carbon is １４ C / １２ The process comprising producing, characterized by a renewable carbon content of at least 90%, as determined by measurement of the 1C isotope ratio.

17. The process according to claim 16, wherein the reducing gas contains at least 10 mol% hydrogen.

18. The process according to claim 16, wherein the reducing gas contains at least 10 mol% carbon monoxide.

19. The process according to claim 16, further comprising increasing the hydrogen content of the reducing gas via a water-gas shift reaction.

20. The process according to claim 16, wherein the selected reactant in step (d) is water.

21. The process according to claim 16, wherein the selected reactant in step (d) is oxygen, and the oxygen is included in air, pure oxygen, concentrated oxygen, ozone, or a combination thereof.

22. The process according to claim 16, wherein the activated carbon is characterized by an iodine value of at least 500.

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