Carbon Technology Holdings, LLC

This invention provides processes and systems for converting biomass into high-carbon biogenic reagents that are suitable for a variety of commercial applications. Some embodiments employ pyrolysis in the presence of an inert gas to generate hot pyrolyzed solids, condensable vapors, and non-condensable gases, followed by separation of vapors and gases, and cooling of the hot pyrolyzed solids in the presence of the inert gas. Additives may be introduced during processing or combined with the reagent, or both. The biogenic reagent may include at least 70 wt %, 80 wt %, 90 wt %, 95 wt %, or more total carbon on a dry basis. The biogenic reagent may have an energy content of at least 12,000 Btu/lb, 13,000 Btu/lb, 14,000 Btu/lb, or 14,500 Btu/lb on a dry basis. The biogenic reagent may be formed into fine powders, or structural objects. The structural objects may have a structure and/or strength that derive from the feedstock, heat rate, and additives.

The processes disclosed herein are environmentally friendly technologies to produce biocarbon products with low water intensity as well as low carbon intensity. Some variations provide a low-water-intensity process for producing a biocarbon product, comprising: providing a starting feedstock comprising biomass and water; drying the starting feedstock to generate a dried feedstock and a first vapor; pyrolyzing the dried feedstock to generate hot solids and a second vapor; condensing the first vapor to generate a first condensed liquid having a first pH from about 1 to about 7; condensing the second vapor to generate a second condensed liquid having a second pH from about 1 to about 7; forming acid water comprising the first condensed liquid, the second condensed liquid, or a mixture thereof; washing and cooling the hot solids using the acid water, to generate washed, cooled solids; and recovering the washed, cooled solids as a low-water-intensity biocarbon product.

Some variations provide a carbon-negative carbon product that is characterized by a carbon intensity less than 0 kg CO 2 e per metric ton of the carbon-negative carbon product, wherein the carbon-negative carbon product contains at least about 50 wt % carbon. In some embodiments, the carbon intensity is less than −500 kg CO 2 e per metric ton of the carbon-negative carbon product. Other variations provide a carbon-negative metal product (e.g., a steel product) that is characterized by a carbon intensity less than 0 kg CO 2 e per metric ton of the carbon-negative metal product, wherein the metal product contains from 50 wt % to 100 wt % of one or more metals and optionally one or more alloying elements. In some embodiments, the carbon-negative metal product is characterized by a carbon intensity less than −200 kg CO 2 e per metric ton of the carbon-negative metal product. The carbon-negative metal product can contain a wide variety of metals.

In some variations, the invention provides a biocarbon pellet comprising: 35 wt % to 99 wt % of a biogenic reagent, wherein the biogenic reagent comprises, on a dry basis, at least 60 wt % carbon; 0 wt % to 35 wt % water moisture; and 1 wt % to 30 wt % of a binder, wherein the biocarbon pellet is characterized by an adjustable Hardgrove Grindability Index (HGI) from about 30 to about 120, as shown in the Examples. The pellet HGI is adjustable by controlling process conditions and the pellet binder. The binder can be an organic binder or an inorganic binder. The carbon is renewable as determined from a measurement of the 14 C/ 12 C isotopic ratio. Many processes of making and using the biocarbon pellets are described. Applications of the biocarbon pellets include pulverized coal boilers, furnaces for making metals such as iron or silicon, and gasifiers for producing reducing gas.

In some variations, the disclosure provides a renewable biocarbon composition comprising from 50 wt % to 99 wt % total carbon, wherein the biocarbon composition is characterized by a base-acid ratio selected from 0.1 to 10, an iron-calcium ratio selected from 0.05 to 5, iron-plus-calcium parameter selected from 5 to 50 wt %, a slagging factor selected from 0.001 to 1, and/or a fouling factor or modified fouling factor selected from 0.1 to 10. Some variations provide a process comprising: providing a biomass feedstock; pyrolyzing the biomass feedstock to generate an intermediate biocarbon stream; washing or treating the intermediate biocarbon stream with an acid, a base, a salt, a metal, H 2 , H 2 O, CO, CO 2 , or a combination thereof, and/or introducing an additive in the process, to adjust a base-acid ratio or other compositional parameter; and recovering a biocarbon composition comprising from 50 wt % to 99 wt % total carbon and optimized for a compositional parameter.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

Biogenic activated carbon compositions disclosed herein comprise at least 55 wt % carbon, some of which may be present as graphene, and have high surface areas, such as Iodine Numbers of greater than 2000. Some embodiments provide biogenic activated carbon that is responsive to a magnetic field. A continuous process for producing biogenic activated carbon comprises countercurrently contacting, by mechanical means, a feedstock with a vapor stream comprising an activation agent including water and/or carbon dioxide; removing vapor from the reaction zone; recycling at least some of the separated vapor stream, or a thermally treated form thereof, to an inlet of the reaction zone(s) and/or to the feedstock; and recovering solids from the reaction zone(s) as biogenic activated carbon. Methods of using the biogenic activated carbon are disclosed.

The present disclosure provides biorefining systems for co-producing activated carbon along with primary products. A host plant converts a feedstock comprising biomass into primary products and carbon-containing co-products; a modular reactor system pyrolyzes and activates the co-products, to generate activated carbon and pyrolysis off-gas; and an oxidation unit oxidizes the pyrolysis off-gas, generating CO 2 , H 2 O, and energy. The energy is recycled and utilized in the host plant, and the CO 2 and H 2 O may be recycled to the reactor system as an activation agent. The host plant may be a saw mill, a pulp and paper plant, a corn wet or dry mill, a sugar production facility, or a food or beverage plant, for example. In some embodiments, the activated carbon is utilized at the host plant to purify one or more primary products, to purify water, to treat a liquid waste stream, and/or to treat a vapor waste stream.

The invention provides a process for producing biographite from a biocarbon feedstock, comprising: providing a metal-containing species that is a metal carbide or is capable of forming a metal carbide; feeding a biocarbon feedstock and the metal-containing species into a molten metal carbide reactor having a first reaction zone and a second reaction zone, wherein the first reaction zone is operated at a first-zone temperature selected to achieve a molten state comprising the metal carbide, and wherein the second-zone temperature is lower than the first-zone temperature; operating the molten metal carbide reactor to dissolve carbon (from the biocarbon feedstock) in the molten state, thereby generating dissolved carbon, and to produce biographite from the dissolved carbon; recovering biographite product; and recycling a portion of the biographite to the molten metal carbide reactor. The recycled biographite functions as a graphitization template to enhance formation of biographite from the dissolved carbon.

This invention provides processes and systems for converting biomass into high carbon biogenic reagents that are suitable for a variety of commercial applications. Some embodiments employ pyrolysis in the presence of an inert gas to generate hot pyrolyzed solids, condensable vapors, and non-condensable gases, followed by separation of vapors and gases, and cooling of the hot pyrolyzed solids in the presence of the inert gas. Additives may be introduced during processing or combined with the reagent, or both. The biogenic reagent may include at least 70 wt %, 80 wt %, 90 wt %, 95 wt %, or more total carbon on a dry basis. The biogenic reagent may have an energy content of at least 12,000 Btu/lb, 13,000 Btu/lb, 14,000 Btu/lb, or 14,500 Btu/lb on a dry basis. The biogenic reagent may be formed into fine powders, or structural objects.