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WO-2026096439-A1 - PROCESSES AND SYSTEMS FOR CONVERSION OF ANIMAL MANURE TO THERMAL GAS AND BIOCHAR

WO2026096439A1WO 2026096439 A1WO2026096439 A1WO 2026096439A1WO-2026096439-A1

Abstract

Processes and systems are disclosed for converting animal manure into useful energy and materials. Some variations provide a process for converting animal manure into a purified thermal gas, comprising: drying a starting animal manure in a manure dryer; pelletizing the dried animal manure to generate manure pellets; thermally reacting the manure pellets in a thermal reactor to generate an intermediate thermal gas and a solid biochar; separating out the solid biochar; condensing the intermediate thermal gas to generate a cooled thermal gas; compressing the cooled thermal gas to generate a compressed thermal gas; catalytically reacting the compressed thermal gas in a water-gas shift reactor to generate a shifted thermal gas having an adjusted H 2 /CO ratio; treating the shifted thermal gas using an acid-gas removal unit to generate a purified thermal gas; removing water and/or light gases from the purified thermal gas; and recovering or further processing the purified thermal gas.

Inventors

  • WEBB, CHRIS
  • Oliver, Roger
  • DAUGAARD, DAREN

Assignees

  • W2E Renewable Solutions, Inc.

Dates

Publication Date
20260507
Application Date
20251028
Priority Date
20251027

Claims (20)

  1. 1. A process for converting animal manure into a purified thermal gas, said process comprising: (a) providing starting animal manure, wherein said starting animal manure has an average moisture content from about 30 wt% to about 90 wt% H2O; (b) drying said animal manure in a manure dryer operated at a drying temperature selected from about 50°C to about 350°C to generate a dried animal manure, wherein said dried animal manure has an average moisture content from about 15 wt% to about 40 wt% H2O; (c) pelletizing said dried animal manure in a manure pelletizer to generate manure pellets, wherein said manure pellets have an average moisture content from 0 wt% to about 20 wt% H2O; (d) thermally reacting said manure pellets in a thermal reactor operated at a reaction temperature selected from about 600°C to about 1200°C, to generate an intermediate thermal gas and a solid biochar from said manure pellets, wherein said intermediate thermal gas contains at least H2, CO, CO2, CH4, and H2O, and wherein said solid biochar contains at least carbon and ash; (e) separating said solid biochar from said intermediate thermal gas; (f) optionally, feeding said intermediate thermal gas to a tar-reforming reactor operated at a tar-reforming temperature selected from about 1200°C to about 1600°C; (g) feeding said intermediate thermal gas to a condensing unit, to generate a cooled thermal gas and a separated liquid stream; (h) compressing said cooled thermal gas using a compression unit, to generate a compressed thermal gas, wherein said compressed thermal gas is at a pressure from about 5 bar to about 55 bar; (i) catalytically reacting said compressed thermal gas in a water-gas shift reactor operated at a water-gas shift temperature selected from about 200°C to about 550°C, to generate a shifted thermal gas having an adjusted H2/CO ratio compared to a H2/CO ratio of said compressed thermal gas; Attorney Docket No. W2E- 1001 -PCT (j) treating said shifted thermal gas using an acid-gas removal unit operated to remove at least a portion of carbon dioxide as well as at least a portion of sulfur-containing compounds from said shifted thermal gas, to generate a purified thermal gas; (k) optionally, removing water and/or light gases from said purified thermal gas; and (l) recovering or further processing said purified thermal gas.
  2. 2. The process of claim 1, wherein said starting animal manure has an average moisture content from about 40 wt% to about 60 wt% H2O.
  3. 3. The process of either one of claims 1 or 2, wherein said dried animal manure has an average moisture content from about 15 wt% to about 25 wt% H2O.
  4. 4. The process of any one of claims 1 to 3, wherein said drying temperature is selected from about 80°C to about 200°C.
  5. 5. The process of any one of claims 1 to 4, wherein said manure pelletizer is selected from the group consisting of a single-screw extruder, a double-screw extruder, a granulation unit, and combinations thereof.
  6. 6. The process of any one of claims 1 to 5, wherein said manure pellets have an average moisture content from about 5 wt% to about 15 wt% H2O.
  7. 7. The process of any one of claims 1 to 6, wherein said manure pellets have an average effective length from about 3 millimeters to about 150 millimeters.
  8. 8. The process of any one of claims 1 to 7, wherein said manure pellets have an average effective diameter from about 3 millimeters to about 25 millimeters.
  9. 9. The process of any one of claims 1 to 8, wherein said reaction temperature is selected from about 1000°C to about 1200°C.
  10. 10. The process of claim 9, wherein said reaction temperature is selected from about 1050°C to about 1150°C. Attorney Docket No. W2E- 1001 -PCT
  11. 11. The process of any one of claims 1 to 10, wherein step (d) includes introducing a sub- stoichiometric quantity of oxygen into said thermal reactor.
  12. 12. The process of any one of claims 1 to 11, wherein step (d) includes introducing a catalyst into said thermal reactor.
  13. 13. The process of any one of claims 1 to 12, wherein step (e) includes removing said solid biochar by gravity directly from said thermal reactor.
  14. 14. The process of any one of claims 1 to 13, wherein step (e) includes removing said solid biochar from said intermediate thermal gas downstream of said thermal reactor.
  15. 15. The process of claim 14, wherein step (e) includes using a cyclone and/or an electrostatic precipitator to remove fine particles of said solid biochar from said intermediate thermal gas.
  16. 16. The process of any one of claims 1 to 15, wherein step (f) is performed.
  17. 17. The process of claim 16, wherein said tar-reforming temperature is at least 1300°C.
  18. 18. The process of claim 16, wherein oxygen is introduced to said tar-reforming reactor.
  19. 19. The process of claim 16, wherein a tar-reforming catalyst is introduced to said tarreforming reactor.
  20. 20. The process of any one of claims 1 to 19, wherein said water-gas shift temperature is selected from about 300°C to about 450°C.

Description

Attorney Docket No. W2E- 1001 -PCT PROCESSES AND SYSTEMS FOR CONVERSION OF ANIMAL MANURE TO THERMAL GAS AND BIOCHAR PRIORITY DATA [0001] This international patent application claims priority to U.S. Provisional Patent App. No. 63/714,956, filed on November 1, 2024, and to U.S. Patent App. No. 19/370,005, filed on October 27, 2025, each of which is hereby incorporated by reference. FIELD OF THE INVENTION [0002] The present invention generally relates to processes and systems for converting animal manure into useful materials and energy. BACKGROUND OF THE INVENTION [0003] Livestock manure, such as cattle manure, is generated in enormous quantities globally. The total amount of livestock manure generated worldwide is over 15 million tons per day on a dry basis. Manure is a valuable source of nutrients for crops and can improve soil productivity. These nutrients primarily include nitrogen, phosphorus, and potassium. However, management of manure and its nutrients poses a significant challenge. [0004] Applying too much manure on an area of land can cause over-fertilization. Land over-fertilization causes the grass to grow excessively and can alter the chemical composition of the grass, producing compounds that can taste bitter or unpalatable to cows. As a result, cows may choose to graze on other areas of the pasture with less-fertilized grass, leading to uneven grazing patterns. Secondary impacts of over-fertilization include algae blooms causing the depletion of oxygen in surface waters, pathogens and nitrates in drinking water, and the emission of odors and gases into the air. Nutrients from excess manure enter lakes and streams through runoff and soil erosion, causing water contamination. Attorney Docket No. W2E- 1001 -PCT [0005] When manure is composted or is anaerobically digested, the microorganisms generate not only carbon dioxide, but also methane and nitrous oxide. Methane has an order of magnitude higher greenhouse-gas potential compared to carbon dioxide, while nitrous oxide has two orders of magnitude higher greenhouse-gas potential compared to carbon dioxide. For these reasons, livestock manure produces over 10% of global greenhouse gas emissions. There is a strong desire to better manage manure to reduce greenhouse gas emissions. [0006] In principle, methane (biogas) can be collected during anaerobic digestion of livestock manure. Anaerobic digestion is a process where the organic matter is broken down in an oxygen-deficient environment, releasing methane, CO2, and solid sludge. Anaerobic digestion is a four-stage process comprising hydrolysis, acidogenesis, acetogenesis, and methanogenesis. Anaerobic digestion of manure poses many challenges. For example, the digestion uses various microorganisms each requiring different temperatures. Creating an environment where all the microorganisms can thrive for optimum biogas production is difficult. Also, animal manure often contains a recalcitrant lignocellulosic component which is difficult to hydrolyze. The unhydrolyzed lignocellulosic component results in incomplete degradation and reduced methane production. Another challenge with anaerobic digestion is that the carbon-to-nitrogen (C:N) ratio has a substantial influence on the process, usually because the substrate is too rich in nitrogen. A low C:N ratio limits most conventional anaerobic digestion processes. Because anaerobic digestion of manure is so challenging, it has been estimated that in the U.S., only 5% of cattle manure is anaerobically digested while 95% is simply spread on land. [0007] On a dry basis, the carbon content of animal manure is typically about 40- 45%. This means that fundamentally, animal manure has a stoichiometry that should allow it to be converted to useful energy, fuels, and chemicals. The prior art has not yet provided the appropriate chemical engineering to enable efficient industrial use of animal manure. [0008] In view of the challenges and desires in the art, there is a commercial need for improved processes and systems to convert animal manure (especially cattle manure) into useful energy and materials. Attorney Docket No. W2E- 1001 -PCT SUMMARY OF THE INVENTION [0009] The present invention addresses the aforementioned needs in the art, by providing various processes and systems to convert manure into useful energy and/or materials. [0010] Some variations provide a process for converting animal manure (e.g., dairy manure) into a purified thermal gas, the process comprising: (a) providing starting animal manure, wherein the starting animal manure has an average moisture content from about 30 wt% to about 90 wt% H2O; (b) drying the animal manure in a manure dryer operated at a drying temperature selected from about 50°C to about 350°C to generate a dried animal manure, wherein the dried animal manure has an average moisture content from about 15 wt% to about 40 wt% H2O; (c) pelletizing the dried animal manure in a manure pelletizer to generate manure pellets, whe