Search

CN-122029253-A - Method for producing biofuel

CN122029253ACN 122029253 ACN122029253 ACN 122029253ACN-122029253-A

Abstract

The present invention relates to a method for producing biofuel and to an apparatus for carrying out the method. In particular, the present invention relates to a method and apparatus for producing Sustainable Aviation Fuel (SAF).

Inventors

  • S. N.M. Lima
  • P. I. Hildich
  • J. P. Haigate

Assignees

  • 萤火虫绿色燃料有限公司

Dates

Publication Date
20260512
Application Date
20240726
Priority Date
20230728

Claims (20)

  1. 1. A method for producing a hydrocarbon fuel, the method comprising: (i) Subjecting a slurry of waste material comprising one or more of sewage sludge, animal slurry, microalgae cultivation paste, effluent from paper mill and palm oil mill and slaughterhouse waste to a hydrothermal liquefaction reaction to obtain a hydrothermal liquefaction product, wherein the hydrothermal liquefaction reaction is carried out at a residence time of 15-25 minutes, a temperature of 280-373 ℃ and a pressure of 18 MPa to 22 MPa; (ii) Separating biological oil from the hydrothermal liquefaction product, and (Iii) The bio-oil is treated to provide a hydrocarbon fuel.
  2. 2. The method of claim 1, wherein the hydrocarbon fuel is one or more of a sustainable aviation fuel, a marine fuel, a road fuel, a heating fuel, or a generator fuel.
  3. 3. The method of any one of the preceding claims, further comprising preparing a slurry of waste material prior to hydrothermal liquefaction, comprising adding a diluent to the waste material, and optionally mixing or homogenizing the slurry.
  4. 4. The method of any one of the preceding claims, wherein the waste material comprises sewage sludge, and wherein the sewage sludge comprises anaerobically digested sewage sludge.
  5. 5. The method of claim 4, wherein the sewage sludge has a solids content of 20 to 30 wt% prior to use in preparing a slurry.
  6. 6. The method according to any of the preceding claims, wherein the slurry of waste material has a dry solids content of 20 wt% or less, preferably wherein the slurry of waste material has a dry solids content of 10-20 wt%.
  7. 7. The method of any one of the preceding claims, wherein the hydrothermal liquefaction reaction comprises subjecting the slurry of waste material to a temperature of 300-350 ℃.
  8. 8. The method of any one of the preceding claims, wherein the hydrothermal liquefaction reaction comprises subjecting the slurry of waste material to a pressure of 19-21 MPa (190-210 bar) or 20 MPa (200 bar).
  9. 9. The method of any one of the preceding claims, wherein the slurry of waste material has a residence time of at least 16, 18, or 20 minutes in hydrothermal liquefaction conditions.
  10. 10. The method of any one of the preceding claims, wherein the separating operation comprises using an organic solvent, and wherein the organic solvent is separated, recovered, and recycled by evaporation.
  11. 11. The method of any one of the preceding claims, further comprising separating biochar from the hydrothermal liquefaction product, and optionally treating the biochar to obtain refined biochar.
  12. 12. The method of any of the preceding claims, wherein the operation of treating the bio-oil to provide a hydrocarbon fuel comprises hydrotreating the bio-oil.
  13. 13. The method of claim 12, wherein the operation of hydrotreating the bio-oil comprises hydrodeoxygenation of the bio-oil in the presence of a transition metal based sulfiding catalyst at a temperature of 360-400 ℃ and a pressure of 100-130 bar.
  14. 14. The method of any one of the preceding claims, wherein the operation of treating the bio-oil to provide a hydrocarbon fuel comprises fractionation and/or hydrocracking of the bio-oil.
  15. 15. The method of claim 14, wherein the fractionating and/or hydrocracking produces aviation fuel and heavy fuel, and wherein the method further comprises recycling the heavy fuel to the fractionating and/or hydrocracking reaction to increase the yield of aviation fuel.
  16. 16. The method of claim 15, wherein fractionation and/or hydrocracking of the bio-oil also produces bio-naphtha.
  17. 17. A process according to any one of the preceding claims, wherein the hydrothermal liquefaction reaction and/or the separation of the products of the hydrothermal liquefaction reaction produces an off-gas, and wherein the process comprises using the off-gas or a component thereof as a feedstock for generating synthesis gas, for producing e-fuel, and/or for combusting the off-gas or a component thereof in a heat recovery unit and supplying energy to the hydrothermal liquefaction reaction.
  18. 18. A hydrocarbon fuel produced according to any one of claims 1-17, wherein the hydrocarbon fuel is a sustainable aviation fuel.
  19. 19. The hydrocarbon fuel of claim 18, wherein the content of monocycloparaffins is greater than 10 wt%, and/or wherein the content of multicycloparaffins is greater than 5 wt%, and/or wherein the content of aromatics is greater than 10 wt%.
  20. 20. An apparatus for producing sustainable aviation fuel, the apparatus comprising: A hydrothermal liquefaction reactor configured to receive a slurry of waste material and subject the slurry to a hydrothermal liquefaction reaction to obtain a hydrothermal liquefaction product; a separation unit configured to receive the hydrothermal liquefaction product and separate a bio-oil from the hydrothermal liquefaction product; a processing unit configured to receive the bio-oil and process the bio-oil to obtain a hydrocarbon fuel.

Description

Method for producing biofuel Technical Field The present invention relates to a method for producing biofuel and to an apparatus for carrying out the method. In particular, the present invention relates to a method and apparatus for producing Sustainable Aviation Fuel (SAF). Background There is an increasing need to develop sustainability routes for common fuels, such as aviation fuels. For example, the uk government has set a goal that by 2030, 10% of all aviation fuels should be sustainable aviation fuels. However, current methods of producing sustainable aviation fuels fail to achieve this goal. Sustainable fuels can be produced by a variety of methods. For example, it is known to convert waste vegetable oils and fats (e.g., edible oils) into aviation fuels. However, the volume of used oil is limited, which means that there is not enough quantity to rely on it as the sole solution, and the high monetary value means that it is unlikely to be cost-effective. Gasification of biomass also provides a route for fuel production, but gasification can be a highly energy intensive process and requires a dry feedstock, which limits overall sustainability. In WO2018/076093 A1, a method based on hydrothermal liquefaction (HTL) treatment is described for co-processing high water content wastewater sludge and other lignocellulosic biomass to co-produce biogas and bio-crude. In US2021/0214633 A1, a hydrothermal liquefaction system and method for converting organics or biomass into biocrudes and gases is described. In CN116554912a, a process for producing biomass oil from the hydrothermal liquefaction of sludge under catalysis of steel slag is described. In CN115180790a, the preparation of bio-oil from sludge according to a process comprising conditioning and continuous hydrothermal liquefaction is described. In EE202100001 a, a method and system for hydrothermal liquefaction and gasification of biomass using cavitation is described. This enables the conversion of biomass into chemical feedstocks suitable for the production of fuels and organic chemicals. In cavitation, rapid changes in liquid pressure cause the liquid to form small bubbles ("cavities") filled with vapor where the pressure is relatively low. Pressures up to 15 bar are described. The treatment of bio-oil to provide hydrocarbon fuels is not disclosed in the above documents. In CN116179232a, a system combining liquefaction of municipal sludge with upgrading and production of liquid fuels is described, characterized in that it comprises a hydrothermal liquefaction reaction unit and a separation unit, a hydro-upgrading and separation unit, and a washing unit. The sludge is hydrothermally liquefied at a pressure lower than described herein to obtain a mixed oil phase of biological crude methylene chloride. In the search for more environmentally friendly and sustainable solutions, there is a need to transition to a solution for converting waste into fuel that uses widely available low cost raw materials and relatively low energy processes. It is an object of the present invention to obviate or mitigate one or more of the above disadvantages. The present invention provides an alternative or more efficient solution for converting waste into fuel. Summary of The Invention Hydrothermal treatment of carbonaceous feedstock, such as waste plastics or wood pulp, is another way to produce sustainable fuels. Various conditions and materials have been developed for hydrothermal treatment techniques, an example of such a work being EP2718404B2. However, there is very limited research on the use of very low value raw materials, such as sewage sludge, to produce economically viable fuels. Sewage sludge is a particularly challenging feedstock because of its high content of moisture, ash, and other components in the feedstock. Accordingly, in a first aspect of the invention, a process for producing a hydrocarbon fuel is provided. The method may include subjecting a slurry of waste material to a hydrothermal liquefaction reaction to obtain a hydrothermal liquefaction product. The waste material may comprise one or more of sewage sludge, animal slurry, microalgae cultivation paste, effluent from paper and palm oil mills and slaughterhouse waste. The method may include separating the bio-oil from the hydrothermal liquefaction product. The method may include treating the upgraded bio-oil to provide a hydrocarbon fuel. The term "slurry" is well known in the art, but for the avoidance of doubt, the term herein refers to a mixture of solid particles dispersed in a liquid (e.g. the solid particles may be from sewage sludge). For example, the slurry may be an aqueous slurry. Aqueous slurries are advantageous because they provide a more environmentally friendly and cost effective solution that avoids the use of potentially harmful industrial solvents and chemicals. In particular, it has been found that bio-oils, i.e. synthetic liquid hydrocarbons derived from biomass, can be produced st