An integrated method and apparatus for biomass / organic solid waste conversion to synthetic fuel based on membrane separation enhancement

Abstract

This invention relates to an integrated biomass / organic solid waste conversion system and method for producing synthetic fuel based on membrane separation enhancement. It mainly consists of three parts: an oxygen-permeable membrane module, a pyrolysis gasification membrane reactor, and a dehydration catalytic membrane reactor. It can pyrolyze and gasify biomass or organic solid waste, and then convert the resulting syngas into synthetic fuel. The oxygen-permeable membrane module can separate and capture high-purity oxygen from the air required for pyrolysis gasification. The pyrolysis gasification membrane reactor can perform pyrolysis gasification of biomass / organic solid waste and catalytic reforming to obtain high-quality syngas. The dehydration catalytic membrane reactor can further directionally convert the syngas into synthetic fuel. The pyrolysis gasification membrane reactor, coupled with a porous silicon carbide membrane and an integral catalyst, integrates pyrolysis gasification, crude fuel purification, and reforming decoking functions. The dehydration catalytic membrane reactor, coupled with a hydrogenation catalyst and a dehydration molecular sieve membrane, can achieve hydrogenation and in-situ removal of byproduct water in one step, improving reaction efficiency and product yield.

Description

Technical Field

[0001] This invention patent belongs to the field of biomass / organic solid waste resource utilization technology, and specifically relates to an integrated biomass / organic solid waste conversion to synthetic fuel system and method based on membrane separation enhancement. Background Technology

[0002] my country's energy consumption is mainly based on fossil fuels such as coal, oil, and natural gas, which are major sources of CO2 emissions. Adjusting the energy structure and developing renewable biomass solid waste resource utilization are important ways to achieve CO2 emission reduction targets. my country has abundant biomass reserves, but the overall utilization rate is low (<10%). How to develop economical and effective high-value utilization technologies for low-quality biomass (such as straw and sawdust) is key to improving my country's biomass utilization rate.

[0003] The main utilization pathways of biomass are direct combustion and bioconversion. Direct combustion for power generation and heating is simple and easy to implement, but the utilization rate of biomass energy is relatively low. Bioconversion to produce biofuels and chemicals mainly uses starch-based biomass feedstocks; however, using cellulose-based biomass feedstocks such as straw results in low fermentation efficiency and difficulty in product separation, slowing down its industrialization process. Biomass thermochemical conversion, with its strong adaptability of feedstocks and high conversion efficiency, is considered the most promising technology for industrial development in the 21st century. Biomass thermochemical conversion includes two routes: direct liquefaction and indirect liquefaction. The indirect liquefaction route first gasifies biomass at high temperatures into syngas (mainly composed of H2 and CO), then catalytically converts it into high-value liquid fuels. This route is characterized by easy process control, high product purity, and almost no sulfur or nitrogen impurities. The key to the practical application of this route lies in developing compact reaction systems and equipment.

[0004] The process of biomass high-temperature gasification to syngas is extremely complex, involving four overlapping processes: drying, pyrolysis, oxidation, and reduction. The crude gas produced by biomass gasification not only contains H2, CO, and CO2, but also impurities such as tar, small-molecule hydrocarbons, and particulate residues. The composition of the crude gas is closely related to the biomass feedstock, the gasification environment, and the composition of the gasification medium (CO2 / O2 / H2O). Understanding the biomass gasification mechanism and regulating the composition of the gasification products is crucial. Impurities in the crude gas can easily cause equipment blockage and affect the synthesis of downstream liquid fuels; therefore, purification and reforming are necessary before use in liquid fuel synthesis. Catalytic reforming is an important component of the biomass gasification process, used to further convert tar and hydrocarbon cracking products into syngas. Currently, catalysts mainly include natural catalysts (such as dolomite and olivine), inorganic salt catalysts (such as alkali metals and metal oxides), and synthetic catalysts (such as nickel-based and semi-coke-based metal catalysts). The volatile cracking products have complex compositions and are prone to forming solid carbon layers, leading to catalyst deactivation. Obtaining catalysts with high-temperature resistance to sintering and carbon deposition is a key research focus in this field. Nickel-based catalysts possess high catalytic activity and low cost, showing potential application prospects in biomass gasification processes. However, conventional nickel-based catalysts suffer from drawbacks such as susceptibility to coking and sintering. Currently, the various units (gasification, purification, catalytic reforming, etc.) in biomass pyrolysis gasification processes are relatively independent, resulting in bottlenecks such as low system integration and large footprint. Integrating these units, considering the numerous physicochemical changes involved in the reaction and separation processes of biomass gasification, makes it difficult for integrated equipment to meet the requirements of sufficiently continuous reaction and separation processes.

[0005] Syngas can be used to produce high-value-added synthetic fuels (such as methane, alcohols, dimethyl ether, and biofuel) through catalytic technology. However, the syngas obtained from the pyrolysis and gasification of biomass / organic solid waste contains some CO2, necessitating the development of multifunctional catalysts to achieve CO / CO2 co-hydrogenation. Furthermore, eliminating the inhibitory effect of byproduct water on the hydrogenation reaction is crucial for improving reaction efficiency. Therefore, constructing novel membrane reactors based on high-performance catalysts to achieve in-situ removal of byproduct water during the reaction is a promising research direction. Summary of the Invention

[0006] The technical problem this patent aims to solve is that in current biomass pyrolysis gasification processes, each unit (gasification, purification, catalytic reforming, etc.) is relatively independent, resulting in bottlenecks such as low system integration and large footprint. Furthermore, the pyrolysis gasification process is complex, and integrated equipment struggles to meet the requirements for continuous, integrated reaction and separation. Simultaneously, reaction, mass transfer, and heat transfer processes make it difficult to couple the reaction and separation. This patent proposes an integrated biomass / organic solid waste conversion system and method for synthetic fuel production based on enhanced membrane separation. This system can meet the requirements of multi-point decentralized layouts and reduce the collection radius of biomass / organic solid waste. This invention integrates a pyrolysis gasification membrane reactor and a dehydration catalytic membrane reactor into a single system, achieving synergy between biomass pyrolysis gasification reforming and syngas conversion for synthetic fuel production. It successfully couples the reaction and separation, offering advantages such as high reaction efficiency and good separation effect. The pyrolysis gasification membrane reactor integrates a porous silicon carbide membrane for crude gas purification with the biomass gasification process, while a monolithic catalyst is used for the reforming and removal of impurities such as tar from the crude gas, thereby improving the overall efficiency of biomass gasification and reforming reactions. The dehydration catalytic membrane reactor couples a hydrogenation catalyst with a dehydration molecular sieve membrane to achieve synergistic enhancement of the hydrogenation reaction and in-situ removal of byproduct water, improving reaction efficiency and product yield.

[0007] An integrated biomass / organic solid waste conversion to synthetic fuel device based on membrane separation enhancement, comprising:

[0008] Oxygen-permeable membranes are used to separate oxygen from feed gas.

[0009] The pyrolysis gasification membrane reactor has a porous membrane installed inside, and the retention side of the porous membrane is connected to the biomass feedstock device and the permeation side of the oxygen-permeable membrane, respectively. The retention side of the porous membrane is used for the pyrolysis gasification reaction of the biomass feedstock, and the porous membrane is used to purify particulate impurities in the mixture obtained from the pyrolysis gasification reaction.

[0010] A catalytic reforming catalyst layer is installed on the permeate side of a porous membrane in a pyrolysis gasification membrane reactor to reform the purified gas and obtain syngas.

[0011] The dehydration catalytic membrane reactor is equipped with an integrated catalytic reaction membrane consisting of a hydrogenation catalyst layer and a dehydration molecular sieve membrane. It is used to hydrogenate and dehydrate the syngas obtained from the reforming reaction. The hydrogenation catalyst layer is connected to one end of the syngas outlet of the pyrolysis gasification membrane reactor.

[0012] According to claim 1, the integrated biomass / organic solid waste conversion to synthetic fuel device based on membrane separation enhancement is characterized in that the biomass raw material is one or more of biomass, waste plastics, domestic waste, urban sludge, waste cooking oil, and industrial waste oil; it also includes a CO2 and H2O supply device for separating oxygen from the oxygen permeable membrane and mixing it with CO2 and H2O.

[0013] The pyrolysis gasification membrane reactor is tubular; the porous membrane is tubular, with the inner side of the tube being the retention side and the outer side being the permeation side; the porous membrane is made of silicon carbide; the porous membrane has a length of 0.1-2m, a wall thickness of 0.2-5cm, an inner diameter of 1-10cm, and an average pore size of 1-20μm; the catalytic reforming catalyst layer has a cross-sectional thickness of 0.5-5cm, and the difference between the bed height and the length of the porous membrane is no greater than 0.05-0.2m.

[0014] The catalyst surface of the catalytic reforming catalyst is coated with a zeolite molecular sieve confined nano-metal catalyst coating. The zeolite molecular sieve is any one of MFI, SBA-15, and MCM-41. The catalyst active component is any one or more of inexpensive metals such as Ni, Co, and Mo, while the promoter is any one or more of alkali metals such as Mg, Sr, Ba, and Ca.

[0015] The mass ratio of the catalyst active component to the molecular sieve in the catalytic reforming catalyst is 0.01:1 to 0.10:1; the biomass feedstock feeding device is a fluidized particulate conveyor.

[0016] It also includes a gasifying agent conveying device connected to the retrieval side of the porous membrane for mixing the gasifying agent into the feedstock of the catalytic reforming reaction;

[0017] The vaporizing agent is selected from any one or more of carbon dioxide, oxygen, and water vapor.

[0018] In the integrated catalytic reaction membrane composed of the hydrogenation catalyst layer and the dehydration molecular sieve membrane, the catalyst is any one or more metals such as Rh, Cu, Co, Mo, In, Zn, Zr, and Ni, while the dehydration molecular sieve membrane is any one of molecular sieves such as NaA and DDR. The integrated catalytic reaction membrane includes a tubular dehydration catalytic membrane reactor, with the tube body being a dehydration molecular sieve membrane layer, and the outer wall of the tube covered with a hydrogenation catalyst layer with a thickness of approximately 0.1-2 mm. The tube length is 0.1-2 m, the outer diameter is 4-50 mm, and the thickness of the dehydration molecular sieve membrane layer is 5-50 μm. The hydrogenation refers to the hydrogenation reaction of syngas to obtain alcohols.

[0019] An integrated method for converting biomass / organic solid waste into synthetic fuels based on membrane separation enhancement includes the following steps:

[0020] Step 1: Separate oxygen from the feed gas through an oxygen-permeable membrane;

[0021] Step 2: After mixing oxygen and oxidant, feed it into the pyrolysis gasification membrane reactor. Then feed the crushed biomass raw material into the pyrolysis gasification membrane reactor to carry out the biomass pyrolysis gasification reaction. At the same time, the porous membrane in the pyrolysis gasification membrane reactor is used to purify the particulate impurities in the mixture of the pyrolysis gasification reaction.

[0022] Step 3: The purified gas is reformed using a catalytic reforming catalyst on the permeate side of a porous membrane to obtain syngas.

[0023] Step 4: The syngas obtained from the reforming reaction is hydrogenated and dehydrated using a dehydration catalytic membrane reactor.

[0024] In step 1, the raw material gas is air.

[0025] In step 2, the operating temperature range of the biomass pyrolysis gasification reaction is 400~1000℃; in step 2, the gasifying agent is any one or more of carbon dioxide, oxygen, and water vapor, and the ratio of the gasifying agent to oxygen is 1:1-10.

[0026] The particle size of the pulverized biomass raw material is no greater than 1 mm, and the gas flow rate after mixing the gasifying agent and oxygen is 0.5~4 m / s; the flow rate of the biomass raw material on the surface of the porous membrane during the biomass pyrolysis gasification reaction is 0.5~4 m / s.

[0027] During hydrogenation and dehydration, the temperature range is controlled at 250~300°C, the reactor pressure range is controlled at 2~3MPa, and a purge gas flow rate of 0.1-5m / s is supplied into the tube of the dehydration catalytic membrane reactor, while the synthesis gas flow rate outside the tube is 0.2-4m / s. Beneficial effects

[0028] This invention patent proposes an integrated biomass / organic solid waste conversion system and method for producing synthetic fuel based on membrane separation enhancement. It integrates an oxygen-permeable membrane module, a pyrolysis gasification membrane reactor, and a dehydration catalytic membrane reactor into a single system. The oxygen-permeable membrane module provides a high concentration of oxygen for the biomass / organic solid waste pyrolysis process. The pyrolysis gasification membrane reactor, coupled with a porous silicon carbide membrane and an integral catalyst, integrates pyrolysis gasification, crude fuel purification, and catalytic reforming decoking into a single reactor, effectively reducing equipment space. The dehydration catalytic membrane reactor, coupled with a hydrogenation catalyst and a dehydration molecular sieve membrane, achieves in-situ coupling of syngas conversion and byproduct water removal, disrupting reaction equilibrium and simultaneously improving reaction efficiency and product yield. This integrated system offers advantages such as high efficiency, compact structure, and small size, meeting the layout requirements for multi-point decentralized biomass / organic solid waste resource utilization. Attached Figure Description

[0029] Figure 1 This is a structural diagram of the overall device of this patent. Implementation

[0030] This invention relates to an integrated biomass / organic solid waste conversion system and method for producing synthetic fuel based on membrane separation enhancement. This compact system mainly consists of three parts: an oxygen-permeable membrane module, a pyrolysis gasification membrane reactor, and a dehydration catalytic membrane reactor. The specific structure is as follows: Figure 1 As shown in the diagram, the compact system can pyrolyze and gasify biomass or organic solid waste, and then convert the resulting syngas into synthetic fuels (such as methane, alcohols, dimethyl ether, and green jet fuel). The oxygen-permeable membrane module can separate and capture high-purity oxygen from the air required for pyrolysis and gasification, while the pyrolysis gasification membrane reactor can perform pyrolysis and gasification of biomass / organic solid waste and catalytic reforming to obtain high-quality syngas. The dehydration catalytic membrane reactor can further directionally convert the syngas into synthetic fuels. Specifically, the pyrolysis gasification membrane reactor, coupled with a porous silicon carbide membrane and an integral catalyst, integrates pyrolysis gasification, crude fuel purification, and reforming decoking functions. Under operating conditions, through reasonable structural parameter design, this coupled reactor can enable in-situ catalytic generation and separation of the products from biomass fuel gasification at high temperatures, yielding syngas containing H2 / CO / CO2. The dehydration catalytic membrane reactor, coupled with a hydrogenation catalyst and a dehydration molecular sieve membrane, can achieve hydrogenation and in-situ removal of water as a byproduct in one step, improving reaction efficiency and product yield. This reactor has the advantages of compact structure and high integration, and can meet the requirements of distributed biomass pyrolysis gasification reforming to produce syngas, effectively reducing the biomass collection radius (<50 km).

[0031] The technical solution adopted in this invention is as follows:

[0032] This invention relates to an integrated biomass / organic solid waste conversion system and method for producing synthetic fuels based on membrane separation enhancement. The system comprises three parts: an oxygen-permeable membrane module, a pyrolysis gasification membrane reactor, and a dehydration catalytic membrane reactor. It can be used for the efficient conversion of biomass / organic solid waste into synthetic fuels. The system has advantages such as high efficiency, high integration, and small size, and is suitable for distributed and modular biomass / organic solid waste resource utilization.

[0033] In the aforementioned integrated biomass / organic solid waste conversion to synthetic fuel system, the oxygen-permeable membrane module provides a high concentration of oxygen, reaching 99.999%, to the pyrolysis gasification membrane reactor. The gasifying agent required for the pyrolysis gasification membrane reactor can be any one or more of carbon dioxide, oxygen, and water vapor. Besides biomass, the raw materials can also be one or more of waste plastics, municipal solid waste, urban sludge, waste cooking oil, and industrial waste oil. The oxygen is mixed with the gasifying agent, which is then used in the subsequent pyrolysis reaction. Here, the gasifying agent is any one or more of carbon dioxide, oxygen, and water vapor, with a gasifying agent to oxygen ratio of 1:1-10.

[0034] In the aforementioned integrated biomass / organic solid waste conversion to synthetic fuel system, the pyrolysis gasification membrane reactor consists of a porous silicon carbide membrane and an integral catalyst. The pyrolysis gasification membrane reactor is a vertically arranged tubular stainless steel component, composed of a porous silicon carbide membrane and a foamed silicon carbide integral catalyst bed. The silicon carbide membrane tube is located at the center of the reactor, and the integral catalyst bed is located outside the silicon carbide membrane tube. The raw material enters the silicon carbide membrane tube via fluidization or sedimentation for pyrolysis and gasification. During pyrolysis and gasification, the raw material undergoes incomplete combustion reactions with the gasifying agent, primarily including cracking, oxidation, and reduction reactions. Oxidation releases significant heat, while reduction is endothermic, mainly producing CO and H2. C and water vapor are reactants and affect the overall reaction process. Oxidation involves the combustion of tar and oxygen, while reduction involves the reaction of tar and water vapor. The resulting crude fuel gas is purified by the silicon carbide membrane and then enters the monolithic catalyst bed, where tar and small amounts of hydrocarbon impurities are removed via a steam / dry reforming reaction. The surface of the foamed silicon carbide monolithic catalyst is coated with a zeolite molecular sieve confined nano-metal catalyst coating. The zeolite molecular sieve is any one of MFI, SBA-15, or MCM-41. The active catalyst component is any one or more inexpensive metals such as Ni, Co, and Mo, while the additives are any one or more alkali metals such as Mg, Sr, Ba, and Ca. The molecular sieve-confined nano-metal catalyst coating on the surface of the monolithic catalyst can be prepared by in-situ hydrothermal or steam-assisted synthesis. Organic matter is removed by high-temperature reducing atmosphere calcination, ultimately forming catalytic active sites. The active component and auxiliary agent are confined within the molecular sieve crystal channels or intercrystalline channels, with a mass ratio of active component to molecular sieve of 0.01:1 to 0.10:1. The gasifying agent required for the pyrolysis gasification membrane reactor is any one or more of carbon dioxide, oxygen, and water vapor. The operating temperature range is 400–1000°C, preferably with the reaction temperature of the silicon carbide membrane tube controlled at 600–800°C. Therefore, in this coupled reactor, the catalytic reaction can be simultaneously carried out on the monolithic catalyst while the reactor is purified by the silicon carbide layer. The composition of the syngas can be controlled by changing the gasifying agent composition and the pyrolysis gasification process. Preferably, the particle size of the pulverized biomass feedstock is no greater than 1 mm, and the gas flow rate after mixing the gasifying agent and oxygen is 0.5~4 m / s; the pyrolysis gasification membrane reactor integrates a silicon carbide membrane and an integral catalyst into the biomass gasification system, realizing the synergistic effect of biomass pyrolysis gasification and crude gas purification and reforming; the excellent heat transfer characteristics of silicon carbide can establish a reasonably distributed and controllable temperature field within the reactor, improving the system's stability and conversion efficiency. Preferably, such as Figure 1As shown, the pyrolysis gasification membrane reactor is tubular; the porous membrane is tubular, with the inner side of the tube being the interception side and the outer side being the permeation side; the porous membrane is made of silicon carbide; the porous membrane has a length of 0.1-2m, a wall thickness of 0.2-5cm, an inner diameter of 1-10cm, and an average pore size of 1-20μm; the catalytic reforming catalyst has a cross-sectional thickness of 0.5-5cm, and the difference between the bed height and the length of the porous membrane is no greater than 0.05-0.2m.

[0035] In the aforementioned integrated biomass / organic solid waste conversion to synthetic fuel system, the dehydration catalytic membrane reactor consists of a hydrogenation catalyst and a dehydration molecular sieve membrane. High-quality syngas from the pyrolysis gasification membrane reactor enters the catalyst bed for hydrogenation. The dehydration catalytic membrane reactor primarily couples the hydrogenation catalyst and the dehydration membrane reactor, integrating hydrogenation reaction and in-situ removal of byproduct water. The byproduct water is removed in-situ by the dehydration molecular sieve membrane, effectively disrupting the reaction equilibrium and achieving enhanced reaction separation coupling. After the hydrogenation catalytic reaction, syngas can be used to generate alcohols and other raw materials. In this reactor, the middle section is a tubular membrane composed of a dehydration membrane, while the space between the dehydration membrane and the tube wall is filled with the hydrogenation catalyst. By designing the reaction gas flow rate, catalyst bed structure parameters, and dehydration membrane structure parameters, the coupling of the hydrogenation reaction and the simultaneous integrated membrane dehydration process can be achieved. The catalyst is any one or more metals such as Rh, Cu, Co, Mo, In, ZnZr, and Ni, while the dehydration molecular sieve membrane is any one of molecular sieves such as NaA and DDR. The catalyst can be packed in a fixed bed in the membrane reactor or immobilized in the pores of a dehydration molecular sieve membrane carrier; preferably, a purge gas with a flow rate of 0.1-5 m / s is supplied into the tubes of the dehydration catalytic membrane reactor, and the syngas flows at a velocity of 0.2-4 m / s outside the tubes. During hydrogenation and dehydration treatments, the temperature range is controlled at 250-300°C, and the reactor pressure range is controlled at 2-3 MPa. Figure 1 As shown, the integrated catalytic reaction membrane includes a tubular dehydration catalytic membrane reactor. The tube body is a dehydration molecular sieve membrane layer, and the outer wall of the tube is covered with a hydrogenation catalyst layer with a thickness of about 0.1-2 mm or filled with a conventional catalyst particle fixed bed. The tube length is 0.1-2 m, the outer diameter of the tube is 4-50 mm, and the membrane thickness of the dehydration molecular sieve membrane layer is 5-50 μm. The hydrogenation refers to the hydrogenation reaction of syngas to obtain alcohols.

[0036] The aforementioned integrated biomass / organic solid waste conversion to synthetic fuel system has a certain degree of applicability and is suitable for the pyrolysis, gasification, and reforming of biomass and organic solid waste to produce syngas. The biomass and organic solid waste raw materials include waste resources such as straw, wood chips, plastics, domestic waste, urban sludge, waste cooking oil, and industrial waste oil.

[0037] Furthermore, the biomass or organic solid waste raw materials need to undergo pretreatment such as crushing and dehydration before entering the reactor, and the particle size and moisture content of the raw materials need to be controlled below 5 mm and 30%, respectively. Example

[0038] Biomass pyrolysis gasification to methanol

[0039] First, high-purity oxygen is obtained using an oxygen-permeable membrane for subsequent biomass pyrolysis and gasification to produce syngas. Through the separation effect of the oxygen-permeable membrane, oxygen in the air passes through the membrane layer, and the passed oxygen is mixed with CO2 and H2O as a gasifying agent with a composition of O2:CO2:H2O=10:1.5:0.8.

[0040] A silicon carbide membrane (1 m in length, 0.5 cm in wall thickness, 4 cm in inner diameter, and 5 μm in average pore size) was sealed at both ends with ceramic glaze. The silicon carbide membrane was then placed in the center of a stainless steel or quartz tube reactor, and a certain amount of foamed silicon carbide monolithic catalyst was stacked on the outside of the membrane (catalyst bed height 0.8 m, cross-sectional thickness 2 cm). The monolithic catalyst was a ZSM-5 molecular sieve confined nano-nickel catalyst, with Mg as the additive and a metal active component content of 5 wt.%. High-temperature resistant graphite gaskets were then used to seal the silicon carbide membrane tube to the reactor's end joints. Finally, reactor accessories, such as biomass and gasification agent feedstocks and an outlet cyclone separator, were connected.

[0041] Secondly, check the airtightness of the entire reactor, close the reactor outlet, then introduce a certain amount of nitrogen, close the reactor inlet, and record the reactor pressure change; after more than 3 hours, if the pressure remains unchanged, the airtightness of the entire reactor meets the requirements; otherwise, all joints must be checked for airtightness.

[0042] The reactor heater is heated at 10 °C / min, with the temperature range controlled at 600 °C. The biomass and gasifying agent feed valves are opened, and sawdust, used as the biomass feedstock, is crushed to a particle size no greater than 0.5 mm and fed in a fluidized bed operation (flow rate 1 m / s). The gasifying agent enters the inner side of the silicon carbide membrane at a flow rate of 1 m / s. Solid particles and ash in the crude fuel gas from biomass pyrolysis and gasification are filtered and purified by the silicon carbide membrane, then enter the integral catalyst bed. Through steam / dry reforming, tar and hydrocarbon impurities are catalytically removed to obtain high-quality syngas. After the system stabilizes, the main components of the syngas are CO2 5.6%, H2 57.6%, CO 33.1%, and CH4 5.6%.

[0043] Syngas is delivered to a dehydration catalytic membrane reactor via a compressor. The reactor is 1.5m long and contains a tubular ceramic catalytic membrane with an outer diameter of 20mm. The membrane is coated with a 30μm thick NaA molecular sieve membrane. A copper-based catalyst, approximately 0.5mm thick, is coated within the NaA molecular sieve membrane support. The reactor heater heats the syngas at 10°C / min, maintaining a temperature range of 270°C. The reactor pressure is controlled at 2MPa, and the reactor inner diameter is 25mm. Nitrogen gas is supplied at a flow rate of 1m / s to purge the tubular membrane, while syngas is supplied at a flow rate of 0.5m / s outside the tube. The hydrogenation catalyst in the catalytic membrane reactor efficiently converts syngas into methanol or ethanol, achieving a CO / CO2 total conversion rate of 30% and a methanol selectivity of 85%. Water, a byproduct, is removed in situ by the molecular sieve membrane, disrupting the reaction equilibrium and simultaneously improving reaction efficiency and product yield. Example

[0044] Biomass and organic plastics co-pyrolysis gasification to produce higher alcohols

[0045] First, high-purity oxygen is obtained using an oxygen-permeable membrane for subsequent biomass pyrolysis and gasification to produce syngas. Through the separation effect of the oxygen-permeable membrane, oxygen in the air passes through the membrane layer, and the passed oxygen is mixed with CO2 and H2O as a gasifying agent with a composition of O2:CO2:H2O=1:1.5:0.8.

[0046] A silicon carbide membrane (1 m in length, 0.6 cm in wall thickness, 3 cm in inner diameter, and 4 μm in average pore size) was sealed at both ends with ceramic glaze. The silicon carbide membrane was then placed in the center of a stainless steel reactor, and a certain amount of foamed silicon carbide monolithic catalyst (catalyst bed height 0.9 m, cross-sectional thickness 2.5 cm) was placed around the outside of the silicon carbide membrane. The monolithic catalyst was a mesoporous MCM-41 molecular sieve confined nano-nickel catalyst with a metal active component content of 5 wt.%. High-temperature resistant graphite gaskets were then used to seal the silicon carbide membrane tube to the reactor's end joints. Finally, reactor accessories, such as the biomass and gasification agent feedstock and the outlet cyclone separator, were connected.

[0047] Secondly, check the airtightness of the entire reactor, close the reactor outlet, then introduce a certain amount of nitrogen, close the reactor inlet, and record the reactor pressure change; after more than 3 hours, if the pressure remains unchanged, the airtightness of the entire reactor meets the requirements; otherwise, all joints must be checked for airtightness.

[0048] The reactor heater is heated at 10 °C / min, with the temperature range controlled at 700 °C. The biomass / plastic and gasifying agent inlet valves are opened. Wood chips, used as biomass feedstock, are crushed to a particle size no greater than 0.6 mm and fed via sedimentation (1 kg / h). The gasifying agent enters the inner side of the silicon carbide membrane at a flow rate of 1.5 m / s. Solid particles and ash in the crude fuel gas from plastic pyrolysis gasification are filtered and purified by the silicon carbide membrane before entering the integral catalyst bed. Through steam / dry reforming, tar and hydrocarbon impurities are catalytically removed to obtain high-quality syngas. After the system stabilizes, the main components of the syngas are CO2 5.5%, H2 52.7%, CO 35.7%, and CH4 6.1%.

[0049] Syngas is delivered to a dehydration catalytic membrane reactor via a compressor. The reactor is 2 m long and contains a tubular ceramic catalytic membrane with an outer diameter of 30 mm. The membrane is coated with a 40 μm thick NaA molecular sieve membrane, and a molybdenum sulfide-based catalyst (approximately 0.4 mm thick) is coated on the surface of the NaA molecular sieve membrane to catalyze the synthesis of higher alcohols from syngas. The reactor is heated at a rate of 10 °C / min, with the temperature controlled within a range of 280 °C. The reactor pressure is controlled within a range of 2.5 MPa. The reactor has an inner diameter of 30 mm. Nitrogen gas is supplied at a flow rate of 0.8 m / s to purge the tubular membrane, while the syngas is supplied at a flow rate of 0.4 m / s outside the tube. The molybdenum sulfide-based catalyst in the catalytic membrane reactor efficiently converts syngas into higher alcohols, achieving a CO conversion rate of 26.28% and an alcohol selectivity of 22.76%. C6+ ions account for approximately 26-28% of the alcohols in the product, while the byproduct water is removed in situ by the molecular sieve membrane, disrupting the reaction equilibrium and simultaneously improving reaction efficiency and product yield.

Claims

1. An integrated biomass / organic solid waste conversion to synthetic fuels based on membrane separation intensified device, characterized in that, include: Oxygen-permeable membranes are used to separate oxygen from feed gas. The pyrolysis gasification membrane reactor has a porous membrane installed inside, and the retention side of the porous membrane is connected to the biomass feedstock device and the permeation side of the oxygen-permeable membrane, respectively. The retention side of the porous membrane is used for the pyrolysis gasification reaction of the biomass feedstock, and the porous membrane is used to purify particulate impurities in the mixture obtained from the pyrolysis gasification reaction. A catalytic reforming catalyst layer is installed on the permeate side of a porous membrane in a pyrolysis gasification membrane reactor to reform the purified gas and obtain syngas. A dehydration catalytic membrane reactor is installed with an integrated catalytic reaction membrane consisting of a hydrogenation catalyst layer and a dehydration molecular sieve membrane. It is used to hydrogenate and dehydrate the syngas obtained from the reforming reaction. The hydrogenation catalyst layer is connected to one end of the syngas outlet of the pyrolysis gasification membrane reactor. The biomass raw materials are one or more of biomass, waste plastics, domestic waste, urban sludge, gutter oil, and industrial waste oil; it also includes a CO2 and H2O supply device, which is used to separate oxygen from the oxygen permeable membrane and mix it with CO2 and H2O to form a mixed gasification agent; The pyrolysis vaporization membrane reactor is tubular; the porous membrane is tubular, with the inner side of the tube being the retention side and the outer side being the permeation side; the porous membrane is made of silicon carbide. The porous membrane has a length of 0.1-2m, a wall thickness of 0.2-5cm, an inner diameter of 1-10cm, and an average pore size of 1-20μm; the cross-sectional thickness of the catalytic reforming catalyst layer is 0.5-5cm, and the difference between the bed height and the length of the porous membrane is no greater than 0.05-0.2m. The hydrogenation catalyst layer and the dehydration molecular sieve membrane constitute an integrated catalytic reaction membrane. The catalyst is any one or more of Rh, Cu, Co, Mo, In, Zn, Zr, and Ni, and the dehydration molecular sieve membrane is any one of NaA or DDR molecular sieve. The integrated catalytic reaction membrane includes a tubular dehydration catalytic membrane reactor. The tube body is a dehydration molecular sieve membrane layer, and the outer wall of the tube is covered with a hydrogenation catalyst layer with a thickness of 0.1-2 mm. The tube length is 0.1-2 m, the outer diameter of the tube is 4-50 mm, and the membrane thickness of the dehydration molecular sieve membrane layer is 5-50 μm. The hydrogenation refers to the hydrogenation reaction of syngas to obtain alcohols.

2. The integrated biomass / organic solid waste conversion to synthetic fuel device based on membrane separation enhancement according to claim 1, characterized in that, The catalyst surface in the catalytic reforming catalyst layer is coated with a zeolite molecular sieve confined nano-metal catalyst coating. The zeolite molecular sieve is any one of MFI, SBA-15, and MCM-41. The catalyst active component is any one or more of Ni, Co, or Mo, and the promoter is any one or more of Mg, Sr, Ba, or Ca. The mass ratio of the catalyst active component to the molecular sieve in the catalytic reforming catalyst is 0.01:1 to 0.10:1; the biomass feedstock feeding device is a fluidized particulate conveyor. It also includes a gasifying agent conveying device connected to the retrieval side of the porous membrane, used to supply the mixed gasifying agent to the raw materials of the biomass pyrolysis gasification reaction.

3. A method for integrated biomass / organic solid waste conversion to synthetic fuel based on membrane separation enhancement, characterized in that, The apparatus of claim 1 comprises the following steps: Step 1: Separate oxygen from the feed gas through an oxygen-permeable membrane; Step 2: The mixed gasification agent is fed into the pyrolysis gasification membrane reactor. The crushed biomass raw material is fed into the pyrolysis gasification membrane reactor to carry out the biomass pyrolysis gasification reaction. At the same time, the porous membrane in the pyrolysis gasification membrane reactor is used to purify the particulate impurities in the mixture of the pyrolysis gasification reaction. Step 3: The purified gas is reformed using a catalytic reforming catalyst on the permeate side of a porous membrane to obtain syngas. Step 4: The syngas obtained from the reforming reaction is hydrogenated and dehydrated using a dehydration catalytic membrane reactor.

4. The integrated biomass / organic solid waste conversion to synthetic fuel method based on membrane separation enhancement according to claim 3, characterized in that, In step 1, the raw material gas is air.

5. The integrated biomass / organic solid waste conversion to synthetic fuel method based on membrane separation enhancement according to claim 4, characterized in that, In step 2, the operating temperature range for the biomass pyrolysis gasification reaction is 400~1000℃.

6. The integrated biomass / organic solid waste conversion to synthetic fuel method based on membrane separation enhancement according to claim 5, characterized in that, The particle size of the crushed biomass raw material is no greater than 1 mm; the flow velocity of the biomass raw material on the surface of the porous membrane during the biomass pyrolysis and gasification reaction is 0.5~4 m / s.

7. The integrated biomass / organic solid waste conversion to synthetic fuel method based on membrane separation enhancement according to claim 6, characterized in that, In step 4, the temperature range is controlled between 250 and 300°C, and the reactor pressure range is controlled between 2 and 3 MPa during hydrogenation and dehydration.

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