Method for producing sustainable aviation fuel by using kitchen waste
By converting the kitchen garbage into SAF through anaerobic fermentation and ketatic reactions, it solves the problem of efficient production of aviation fuel in existing technology, and has achieved significant reduction in SAF efficient production and carbon emissions.
Patent Information
- Application Number
- CN202411768707.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-04
- Publication Date
- 2025-01-28
AI Technical Summary
The prior art is difficult to efficiently utilize food waste to produce sustainable aviation fuel (SAF) suitable for aviation fuel, and the carbon emission problems of traditional methods have not been effectively solved.
By crushing the kitchen garbage for anaerobic fermentation, generates volatile fatty acids (VFA) raw materials, and then use a solid oxide catalyst in the ketite tower for ketite reactions to form ketone -like compounds and transform into linearly through hydrogenation reactions into linear. The alkanes and branches of amortic alkone are finally blended into SAFs of different freezing points.
The efficient production of SAF, which is suitable for aviation fuel, has a wide range of applicable scope, can significantly reduce carbon emissions in the aviation industry, and provide more effective emission reduction solutions.
Smart Images
Figure CN119372265A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of biofuel and waste resource utilization. It converts wet waste through biological and catalytic methods to reduce carbon emissions and provide sustainable aviation fuel substitutes. It involves the production of sustainable aviation fuel (SAF), especially using volatile fatty acids (VFA) produced by fermentation of food waste to prepare liquid fuel suitable for aviation use. Background Art
[0002] The rapid development of the aviation industry has led to an increasing demand for fuel, and the carbon emission problem of traditional fossil fuels has become more serious, making sustainable aviation fuel an important way to reduce emissions and gaining widespread attention. The current SAF mainly relies on the hydrogenation of fatty acid esters and fatty acids, which use animal and vegetable oils and fats as raw materials. However, the supply of these resources is limited, and there is a problem of competition with food resources. Therefore, the development of raw materials that do not compete with food resources, such as wet waste, has important application prospects. At present, the treatment of food waste is traditionally based on anaerobic digestion, which produces biogas that can be used as energy, but its efficiency is limited and it is difficult to meet the demand for aviation fuel. There is a need for a method for producing aviation fuel from food waste to efficiently produce aviation fuel, meet the demand for aviation fuel, and reduce carbon emissions in the aviation industry. Summary of the invention
[0003] In view of the shortcomings of the prior art, the present invention provides a method for producing sustainable aviation fuel using food waste. The final SAF produced by this method has a wide range of applications, is suitable for the environmental protection requirements of aviation fuel, can significantly reduce carbon emissions in the aviation industry, and provide a more effective solution for aviation emission reduction goals.
[0004] To achieve the above object, the present invention provides the following technical solution: a method for producing sustainable aviation fuel using food waste, the method comprising: S1: crushing the kitchen waste; S2: putting the pulverized food waste in S1 into a fermentation tank, and performing anaerobically fermentation on the food waste using microbial communities under anaerobic conditions to obtain VFA raw materials; S3: placing the VFA raw material into a ketonization tower, and performing a ketonization reaction under the action of a solid oxide catalyst, wherein the main product of the ketonization reaction is a ketone compound, and water and carbon dioxide are released at the same time; S4: hydrogenating the ketone compound obtained in S3 to generate at least two alkanes under the action of a catalyst for promoting conversion; S5: Mix the various alkanes in S4 in proportion to obtain SAFs with different freezing points.
[0005] Preferably, in step S2, the steps of anaerobic fermentation are: SS1: Hydrolysis of food waste using microbial flora; SS2: Inoculate the fermenter with specific strains to generate an acid-producing microbial community; SS3: A VFA mixture is generated through the action of the acid-producing microbial community in SS2, and the VFA raw materials are obtained after processing.
[0006] Preferably, in step SS1: The specific strains are used for anaerobic digestion of sewage sludge; The fermentation temperature during the hydrolysis process is 50-60°C; pH value is 5.5-6.5; The duration of stay is 2-3 days.
[0007] Preferably, in step SS3: In the early stage of VFA generation, nutrients are added from 0 to 30 days to promote the growth of acid-producing biological communities. During this period, the amount of crushed kitchen waste added every day is 5% of the volume of the fermentation tank. No nutrients are added from 30 to 60 days, and the amount of crushed kitchen waste added every day is 10% of the volume of the fermentation tank. The concentration of VFA mixture during generation was controlled at 10-30 g / L; The VFA mixture is separated by membrane to obtain VFA raw materials.
[0008] Preferably, in step S3, the solid oxide catalyst in the ketonization reaction is zirconium dioxide; The VFA raw material feed flow rate is controlled within the space velocity range of 1-1.5 tons / hour; Ketone reaction temperature is 190-250°C; The residence time is 50-100 hours.
[0009] Preferably, in step S3, the ketonization reaction is to convert the short-chain VFA raw materials produced by fermentation into C5-C15 ketone compounds, which are divided into longer-chain ketone compounds of C8-C15 and shorter-chain ketone compounds of C5-C7.
[0010] Preferably, the hydrogenation reaction of the C8-C15 longer chain ketone compound is as follows: SS1: Pump C8-C15 longer chain ketone compounds into the hydrodeoxygenation reaction tower, add hydrogen, and generate alcohols through the action of the conversion catalyst; SS2: The alcohol in step SS1 is further dehydrated to generate linear alkanes and water, and high-purity linear alkanes are obtained after graded condensation.
[0011] Preferably, in the hydrogenation reaction of the C8-C15 longer chain ketone compounds, the conversion-promoting catalyst is 3 wt% of platinum-based alumina; The hydrogen flow rate is 1.5-2 times the molar ratio of C8-C15 longer chain ketone compounds; The reaction temperature is controlled at 250-350°C; The reaction pressure is 3-6 Mpa; The residence time is 10-48 hours.
[0012] Preferably, the conversion-promoting catalyst in the hydrogenation reaction of the C5-C7 shorter chain ketone compound includes a conversion-promoting catalyst 1 and a conversion-promoting catalyst 2, and the hydrogenation reaction process is: SS1: C5-C7 short-chain ketone compounds are added with a catalyst for promoting conversion, and a polymerization reaction is carried out in a solvent decane to generate enone compounds; SS2: adding hydrogen to the ketene compound generated in step SS1 to perform an isomerization reaction through the action of the second conversion catalyst to generate branched isoalkanes and a small amount of water; SS3: After water is condensed and separated from the product using a condenser, high-purity branched-chain isoparaffins are obtained.
[0013] Preferably, in the hydrogenation reaction step SS1 of the C5-C7 shorter chain ketone compound: The first catalyst for promoting the conversion of the polymerization reaction is niobium pentoxide; The reaction temperature is controlled at 100-150°C; The pressure is normal pressure; The reaction time is 12-24 hours; In step SS2: The second catalyst for promoting the conversion of the isomerization reaction is 3wt% Pt / aluminum trichloride; The molar ratio of hydrogen flow rate to ketene compound is 2-3 times; The reaction temperature is 250-300°C; The reaction pressure is 3-6 MPa; The residence time is 10-24 hours.
[0014] Beneficial effects of the present invention: 1. By controlling the anaerobic digestion process and stopping the reaction before the methanogenic stage, a mixture of short-chain and medium-chain VFA can be obtained. The VFA mixture is separated by membrane to obtain VFA raw materials. VFA raw materials can be used as ideal intermediates for SAF production. After classified hydrogenation reactions, linear alkanes and branched isoalkanes are generated. Linear alkanes and branched isoalkanes are blended in different proportions to obtain SAFs with different freezing points. The final SAF has a wide range of applications, is suitable for the environmental protection requirements of aviation fuel, and meets market demand.
[0015] 2. The method for producing aviation fuel provided in the present invention is not only environmentally friendly, but also significantly reduces aviation carbon footprint. Compared with animal and vegetable oils and fats, it can significantly reduce carbon emissions in the aviation industry and provide a more effective solution for aviation emission reduction goals. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a conversion flow chart of the food waste-derived sustainable aviation fuel (SAF) in the present invention. DETAILED DESCRIPTION
[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0018] like Figure 1 As shown, the present invention provides a method for producing sustainable aviation fuel using food waste, the method comprising: S1: crushing the kitchen waste; S2: putting the pulverized food waste in S1 into a fermentation tank, and performing anaerobically fermentation on the food waste using microbial communities under anaerobic conditions to obtain VFA raw materials; S3: heating the VFA raw material so that it enters the ketonization tower in a gaseous state, and undergoes a ketonization reaction under the action of a solid oxide catalyst. The main product of the ketonization reaction is ketone compounds, and water and carbon dioxide are released at the same time; S4: hydrogenating the ketone compound obtained in S3 to generate at least two alkanes under the action of a catalyst for promoting conversion; S5: Blend the various alkanes in S4 in proportion.
[0019] In step S2, the steps of anaerobic fermentation are: SS1: Using microbial flora to hydrolyze food waste in the fermentation tank; SS2: Inoculate the fermenter with specific strains to generate an acid-producing microbial community; SS3: A VFA mixture is generated through the action of the acid-producing microbial community in SS2, and the VFA raw materials are obtained after processing.
[0020] In step SS1: The specific strains are used for anaerobic digestion of sewage sludge; The fermentation temperature during the hydrolysis process is 50-60°C; pH value is 5.5-6.5; The duration of stay is 2-3 days.
[0021] In step SS3: In the early stage of VFA generation, nutrients are added within 0-30 days. As a preferred solution, the nutrients are a small amount of nitrogen source (urea 500PPM / day) and phosphorus source (potassium phosphate 100PPM / day) to promote the growth of acid-producing biological communities. During this period, the amount of crushed kitchen waste added every day is 5% of the volume of the fermentation tank. No nutrients are added from 30 to 60 days, and the amount of crushed kitchen waste added every day is 10% of the volume of the fermentation tank. The concentration of VFA mixture during production was controlled at 10-30 g / L; The VFA mixture is separated by membrane to obtain VFA raw materials.
[0022] In step S3, the solid oxide catalyst in the ketonization reaction is zirconium dioxide (ZrO2); The VFA raw material feed flow rate is controlled within the space velocity range of 1-1.5 tons / hour; Ketone reaction temperature is 190-250°C; The residence time is 50-100 hours.
[0023] In step S3, the ketonization reaction is to convert the short-chain VFA raw materials produced by fermentation into C5-C15 ketone compounds, which are divided into longer-chain ketone compounds of C8-C15 and shorter-chain ketone compounds of C5-C7.
[0024] The hydrogenation reaction of C8-C15 longer chain ketone compounds is as follows: SS1: Pump C8-C15 longer chain ketone compounds into the hydrodeoxygenation reaction tower, add hydrogen, and generate alcohols through the action of the conversion catalyst; SS2: The alcohol in step SS1 is further dehydrated to generate linear alkanes and water, and high-purity linear alkanes are obtained after graded condensation.
[0025] In the hydrogenation reaction of C8-C15 longer chain ketone compounds, the conversion catalyst is 3wt% platinum-based alumina (Al2O3); The hydrogen flow rate is 1.5-2 times the molar ratio of C8-C15 longer chain ketone compounds; The reaction temperature is controlled at 250-350°C; The reaction pressure is 3-6Mpa; The residence time is 10-48 hours.
[0026] The conversion-promoting catalyst in the hydrogenation reaction of C5-C7 shorter chain ketone compounds includes a conversion-promoting catalyst 1 and a conversion-promoting catalyst 2, and the hydrogenation reaction process is: SS1: C5-C7 short-chain ketone compounds are added with a catalyst for promoting conversion, and a polymerization reaction is carried out in a solvent decane to generate enone compounds; SS2: adding hydrogen to the ketene compound generated in step SS1 to perform an isomerization reaction through the action of the second conversion catalyst to generate branched isoalkanes and a small amount of water; SS3: After water is condensed and separated from the product using a condenser, high-purity branched-chain isoparaffins are obtained.
[0027] In the hydrogenation reaction step SS1 of C5-C7 shorter chain ketone compounds: The first catalyst for promoting the conversion of the polymerization reaction is niobium pentoxide (Nb2O5); The reaction temperature is controlled at 100-150°C; The pressure is normal pressure; The reaction time is 12-24 hours; In step SS2: The second catalyst for promoting the conversion of the isomerization reaction is 3wt% Pt / aluminum trichloride (AlCl3); The molar ratio of hydrogen flow rate to ketene compound is 2-3 times; The reaction temperature is 250-300°C; The reaction pressure is 3-6MPa; The residence time is 10-24 hours.
[0028] During the implementation of this method: the composition of food waste is complex and may contain solid particles, fat, protein, cellulose, etc. First, it is pulverized to make the raw materials uniform to improve the fermentation efficiency. The pulverized food waste is treated by anaerobic fermentation. Anaerobic fermentation is generally divided into four stages: hydrolysis, acidification, acetic acid production stage and methanogenic stage. In order to obtain a VFA mixture, the fermentation is usually stopped in the acetic acid production stage to prevent the VFA mixture from being further converted into methane. In the fermentation tank, the food waste is decomposed by microbial communities under anaerobic conditions. The VFA mixture produced by the domesticated microbial community is 0.5 kg of VFA mixture per kilogram of food waste. The VFA mixture mainly contains C2 to C8, such as acetic acid, propionic acid, butyric acid, etc. The VFA raw material (500-600g / L) obtained by membrane separation of the VFA mixture enters the next process, namely ketonization reaction. Ketonization reaction is to convert the short-chain VFA raw material produced by fermentation into the corresponding ketone compounds of longer-chain ketone compounds through carbon chain extension in the ketonization reaction, thereby increasing the carbon chain length and removing the oxygen content.
[0029] As a preferred embodiment, the product of the ketonization reaction in the present application is mainly C5 to C15 ketone compounds. For C8-C15 longer-chain ketone compounds, they can be directly hydrogenated to enter the hydrodeoxygenation stage to generate C8-C18 linear alkanes, which are the main components of high-quality aviation fuel. For C5-C7 shorter-chain ketone compounds, condensation treatment is required to increase molecular branches to generate C10 to C14 ene ketone compounds, and then hydrogenation is carried out for hydrodeoxygenation reaction to convert them into branched isoalkanes, mainly C10 to C14 branched isoalkanes and a small amount of water. These branched isoalkanes, as important components of sustainable aviation fuel, have a lower freezing point and higher anti-explosion properties, and are suitable for improving fuel performance and the mixing upper limit of aviation fuel. In this embodiment, two kinds of alkanes, C8-C18 linear alkanes and C10 to C14 branched isoalkanes, are mainly generated. The linear alkanes and the branched isoalkanes are blended in different proportions. As a preferred solution, the blending ratio of the linear alkanes and the branched isoalkanes is 1:2-2:1 (mass ratio), and SAFs with different freezing points are obtained. As a preferred solution, the freezing point range of SAF is -60°C to -40°C. The final SAF has a wide range of application, is suitable for the environmental protection requirements of aviation fuel, and meets market demand.
[0030] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention; therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description. Therefore, it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention, and any figure marks in the claims should not be regarded as limiting the claims involved.
[0031] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A method for producing sustainable aviation fuel using food waste, characterized in that: The method includes: S1: crushing the kitchen waste; S2: putting the pulverized food waste in S1 into a fermentation tank, and performing anaerobically fermentation on the food waste using microbial communities under anaerobic conditions to obtain VFA raw materials; S3: heating the VFA raw material so that it enters the ketonization tower in a gaseous state, and undergoes a ketonization reaction under the action of a solid oxide catalyst. The main product of the ketonization reaction is ketone compounds, and water and carbon dioxide are released at the same time; S4: hydrogenating the ketone compound obtained in S3 to generate at least two alkanes under the action of a catalyst for promoting conversion; S5: Blend the various alkanes in S4 in proportion.
2. The method for producing sustainable aviation fuel using food waste according to claim 1, characterized in that: In step S2, the steps of anaerobic fermentation are: SS1: Using microbial flora to hydrolyze food waste in the fermentation tank; SS2: Inoculate the fermenter with specific strains to generate an acid-producing microbial community; SS3: A VFA mixture is generated through the action of the acid-producing microbial community in SS2, and the VFA raw materials are obtained after processing.
3. The method for producing sustainable aviation fuel using food waste according to claim 2, characterized in that: In step SS1: The specific strains are used for anaerobic digestion of sewage sludge; The fermentation temperature during the hydrolysis process is 50-60°C; pH value is 5.5-6.5; The duration of stay is 2-3 days.
4. The method for producing sustainable aviation fuel using food waste according to claim 2, characterized in that: In step SS3: In the early stage of VFA generation, nutrients are added from 0 to 30 days to promote the growth of acid-producing biological communities. During this period, the amount of crushed kitchen waste added every day is 5% of the volume of the fermentation tank. No nutrients are added from 30 to 60 days, and the amount of crushed kitchen waste added every day is 10% of the volume of the fermentation tank. The concentration of VFA mixture during production was controlled at 10-30 g / L; The VFA mixture is separated by membrane to obtain VFA raw materials.
5. The method for producing sustainable aviation fuel using food waste according to claim 1, characterized in that: In the step S3, the solid oxide catalyst in the ketonization reaction is zirconium dioxide; The VFA raw material feed flow rate is controlled within the space velocity range of 1-1.5 tons / hour; Ketone reaction temperature is 190-250°C; The residence time is 50-100 hours.
6. The method for producing sustainable aviation fuel using food waste according to claim 1, characterized in that: In step S3, the ketonization reaction is to convert the short-chain VFA raw materials produced by fermentation into C5-C15 ketone compounds, which are divided into C8-C15 longer-chain ketone compounds and C5-C7 shorter-chain ketone compounds.
7. The method for producing sustainable aviation fuel using food waste according to claim 6, characterized in that: The hydrogenation reaction of the C8-C15 longer chain ketone compound is as follows: SS1: Pump C8-C15 longer chain ketone compounds into the hydrodeoxygenation reaction tower, add hydrogen, and generate alcohols through the action of the conversion catalyst; SS2: The alcohol in step SS1 is further dehydrated to generate linear alkanes and water, and high-purity linear alkanes are obtained after graded condensation.
8. The method for producing sustainable aviation fuel using food waste according to claim 7, characterized in that: In the hydrogenation reaction of the C8-C15 longer chain ketone compounds, the conversion catalyst is 3 wt% of platinum-based alumina; The hydrogen flow rate is 1.5-2 times the molar ratio of C8-C15 longer chain ketone compounds; The reaction temperature is controlled at 250-350°C; The reaction pressure is 3-6Mpa; The residence time is 10-48 hours.
9. The method for producing sustainable aviation fuel using food waste according to claim 6, characterized in that: The conversion-promoting catalyst in the hydrogenation reaction of the C5-C7 shorter chain ketone compound includes a conversion-promoting catalyst 1 and a conversion-promoting catalyst 2, and the hydrogenation reaction process is: SS1: C5-C7 short-chain ketone compounds are added with a catalyst for promoting conversion, and a polymerization reaction is carried out in a solvent decane to generate enone compounds; SS2: adding hydrogen to the ketene compound generated in step SS1 to perform an isomerization reaction through the action of the second conversion catalyst to generate branched isoalkanes and a small amount of water; SS3: After water is condensed and separated from the product using a condenser, high-purity branched-chain isoparaffins are obtained.
10. The method for producing sustainable aviation fuel using food waste according to claim 9, characterized in that: In the hydrogenation reaction step SS1 of the C5-C7 shorter chain ketone compound: The first catalyst for promoting the conversion of the polymerization reaction is niobium pentoxide; The reaction temperature is controlled at 100-150°C; The pressure is normal pressure; The reaction time is 12-24 hours; In step SS2: The second catalyst for promoting the conversion of the isomerization reaction is 3wt% Pt / aluminum trichloride; The molar ratio of hydrogen flow rate to ketene compound is 2-3 times; The reaction temperature is 250-300°C; The reaction pressure is 3-6MPa; The residence time is 10-24 hours.