Fluidized bed adsorption enhanced biomass reforming hydrogen production method and system

Abstract

The invention provides a fluidized bed adsorption enhanced biomass reforming hydrogen production method and system, and belongs to the field of biomass hydrogen production. The method comprises the following steps: feeding biomass into a pyrolysis gasification furnace, introducing oxygen and steam, and carrying out pyrolysis gasification on the biomass to generate biomass gas and biomass charcoal; feeding the biomass gas to a reforming hydrogen production furnace; putting the catalyst into a reforming hydrogen production furnace; an adsorbent is put into the regeneration furnace and then enters the reforming hydrogen production furnace through a material returning valve to be mixed with a catalyst, and fluidized binary particles are formed under the action of primary air and secondary air; the biomass gas and the fluidized binary particles are mixed to form a gas-solid mixture, and the biomass gas is converted into H2, CO and CO2 under the action of a catalyst; the adsorbent adsorbs CO2 and converts the CO2 into calcium carbonate; after the gas-solid mixture is separated, the hydrogen-rich synthesis gas is output through an outlet, and binary particles enter a regeneration furnace, are regenerated by a catalyst and desorbed by an adsorbent, and then return to the reforming hydrogen production furnace along with the fed adsorbent. The hydrogen production efficiency is improved, and the cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the field of biomass hydrogen production, and specifically relates to a fluidized bed adsorption-enhanced biomass reforming hydrogen production method and system. Background Art

[0002] Biomass is the only carbon-neutral renewable energy source that can be stably stored over long periods of time and offers the same dispatchability as traditional fossil fuels. Agricultural waste, a passive biomass, is both a pollution source and a resource. Developing biomass energy tailored to local conditions is an inevitable choice for sustainable development and a low-carbon economy. Compared to direct biomass combustion, converting biomass into three-phase materials—gas, liquid, and solid—and then subjecting each product to differentiated processing based on its physical and chemical properties, resulting in the production of high-value-added chemical raw materials and fine chemicals, achieves clean, efficient, and diversified biomass conversion, offering greater economic benefits and market prospects.

[0003] Biomass hydrogen production is a common biomass utilization method in existing technologies, including gasification and reforming. Biomass gasification reacts biomass with a gasifying agent (typically steam, oxygen, or air) at high temperatures to produce hydrogen-rich gas. Reforming converts organic matter in the biomass into hydrogen using a catalyst. In both cases, biomass is simultaneously converted into biochar, bio-oil, or biogas through a chemical process for use as downstream energy or chemical feedstock.

[0004] Traditional biomass gasification hydrogen production technology faces bottlenecks such as high tar content at low temperatures. Furthermore, the gasified product must undergo a complex series of separation, purification, and reforming processes to produce a product that meets product requirements. For example, Chinese invention patent publication number CN114479950B proposes a biomass pyrolysis gasification hydrogen production method and system. This method directly reacts the biomass feedstock with water vapor and produces H2 after gas-solid separation. However, it does not address the impact of tar and sulfur on catalyst deactivation.

[0005] Catalytic biomass reforming hydrogen production generally uses CO2 adsorption, and uses adsorbents to move the chemical reaction toward hydrogen production. On the one hand, this increases hydrogen production and purity, and on the other hand, the separated CO2 can be directly utilized without a high-energy capture process, thus achieving negative carbon emissions. However, adsorption-enhanced biomass reforming hydrogen production still has problems such as low H2 yield, high cost, flow stratification and particle wear between catalyst and adsorbent, mismatch in reaction time scale, and easy carbon deposition and poisoning of the catalyst. For example, the Chinese invention patent with publication number CN106629600A proposes a crude synthesis gas adsorption catalytic hydrogen production process and equipment, which utilizes a reforming catalyst to adsorb CO2 while catalyzing hydrocarbons, tar (C 10H8) and CO are converted into H2 and CO2, and the catalyst is reduced and regenerated using H2. However, this process reduces the H2 yield and the cost of preparing a reforming and catalytic dual-function catalyst is very high. Summary of the Invention

[0006] In view of the above-mentioned defects or deficiencies in the prior art, the present invention aims to provide a fluidized bed adsorption-enhanced biomass reforming hydrogen production method and system, which adopts binary heterogeneous particles as adsorbent and catalyst respectively, and controls the flow state of the binary particles in the dual fluidized bed reactor in combination with the fluidization state parameter control to avoid the damage of the fluidization state caused by the flow stratification of the binary particles, while reducing the loss of catalyst and adsorbent caused by inter-particle wear, alleviating carbon deposition, and improving hydrogen production efficiency.

[0007] In order to achieve the above objectives, the embodiments of the present invention adopt the following technical solutions: In a first aspect, an embodiment of the present invention provides a fluidized bed adsorption-enhanced biomass reforming hydrogen production system, the system comprising: a biomass pyrolysis-gasification device 1, a reforming hydrogen production device 2, a regeneration device 3 and connecting pipelines; Among them, in the biomass pyrolysis-gasification device 1, the biomass feeding device 101 is connected to the top of the pyrolysis gasification furnace 100, the gasification furnace pure oxygen pipeline 102 and the gasification furnace steam pipeline 103 are connected to the upper and middle parts of the pyrolysis gasification furnace 100; the biomass char outlet 104 is located at the bottom of the pyrolysis gasification furnace 100, and the biomass gas pipeline 105 is provided at the bottom of the pyrolysis gasification furnace 100 and connected to the bottom of the reforming hydrogen production furnace 200; In the reforming hydrogen production device 2, the reforming hydrogen production furnace 200 is a tall and thin double-bed structure with a height-to-diameter ratio of >10, the bottom dense phase zone is a bubbling bed, the middle dilute phase zone and the upper dilute phase zone are fast beds, and a reforming furnace heating device 202 is provided outside the furnace body of the upper dilute phase zone; a first steam pipeline 203 is provided at the bottom of the furnace body, and a second steam pipeline 204 is provided in the middle; a catalyst feeding device 201 is connected to the middle and lower part of the reforming hydrogen production furnace 200; the top of the reforming hydrogen production furnace 200 is connected to the reforming furnace cyclone separator 205, and is also provided with a hydrogen-rich synthesis gas outlet 208; the bottom outlet of the reforming furnace cyclone separator 205 is connected to the reforming furnace return valve 206, and the bottom of the reforming furnace return valve 206 is provided with a reforming furnace return valve steam pipeline 207; the reforming furnace return valve 206 is connected to the regeneration furnace; In the regeneration device 3, an adsorbent feeding device 301 is provided at the middle and lower part of the regeneration furnace 300, a regeneration furnace steam pipeline 302 and a regeneration furnace pure oxygen inlet 303 are provided at the bottom, the top is connected to the regeneration furnace cyclone separator 304, and a regeneration furnace heating device 308 is provided outside the furnace body; a CO2-rich outlet 305 is provided at the top of the regeneration furnace cyclone separator 304; a regeneration furnace return valve 306 is provided at the lower part of the regeneration furnace 300, and a regeneration furnace return valve steam pipeline 307 is provided at the bottom of the regeneration furnace return valve 306; the outlet of the regeneration furnace return valve 306 is connected to the lower part of the reforming hydrogen production furnace 200.

[0008] As a preferred embodiment of the present invention, the system also includes a steam generator, which is connected to the treated water pipeline and is used to provide steam for the gasifier steam pipeline 103, the first steam pipeline 203, the second steam pipeline 204, the reformer return valve steam pipeline 207, the regeneration furnace steam pipeline 302 and the regeneration furnace return valve steam pipeline 307.

[0009] As a preferred embodiment of the present invention, the temperature of the biomass gas pipeline is maintained at 400-500°C; the temperature of the reforming hydrogen production furnace is maintained at 600-750°C; and the temperature of the regeneration furnace is maintained at 800-900°C.

[0010] In a second aspect, an embodiment of the present invention further provides a fluidized bed adsorption-enhanced biomass reforming hydrogen production method, which is implemented based on the above-mentioned system and specifically includes: Step S1: feeding the formed biomass particles into a pyrolysis gasification furnace from a biomass feeding device, introducing oxygen into the pure oxygen pipeline of the gasification furnace, and introducing steam into the steam pipeline of the gasification furnace; the formed biomass particles undergo pyrolysis and gasification in the gasification furnace to generate biomass gas and biochar; the biomass gas is transported to the reforming hydrogen production furnace through the biomass gas pipeline, and the biochar is output outside the system for collection and subsequent use; Step S2: transporting the catalyst particles from the catalyst feeding device to the dense phase area in the reforming hydrogen production furnace; transporting the adsorbent particles from the adsorbent feeding device to the regeneration furnace, and then entering the dense phase area in the reforming hydrogen production furnace through the regeneration furnace return valve to mix with the catalyst particles to form binary particles; inputting steam into the reforming hydrogen production furnace through the first steam pipeline and the second steam pipeline to make the catalyst and adsorbent binary particles flow in gas-solid two-phase and mix evenly, and controlling the flow state of the fluidized binary particles; heating the reforming hydrogen production furnace by the reforming hydrogen production furnace heating device to maintain the temperature at 600-750°C; In step S3, the biomass gas is introduced into the reforming hydrogen production furnace and mixed with the fluidized binary particles to form a gas-solid mixture; in the gas-solid mixture, the biomass gas is converted into H2, CO, and CO2 under the action of the catalyst; the CO2 generated by adsorption by the adsorbent is converted into calcium carbonate, further promoting the conversion of the biomass gas; the final gas-solid mixture enters the reforming furnace cyclone separator; In step S4, the gas-solid mixture is separated by a cyclone separator in the reforming furnace, and the separated hydrogen enters the hydrogen separation and purification device through the hydrogen-rich synthesis gas outlet. The purified hydrogen then enters the hydrogen use pipeline through the hydrogen outlet; the separated catalyst and adsorbent binary particles enter the regeneration furnace through the reforming furnace return valve; In step S5, the catalyst and adsorbent binary particles enter the dense phase zone in the middle of the regeneration furnace. Steam is introduced into the steam pipeline of the regeneration furnace to place the binary particles in a bubbling bed flow state. Simultaneously, the catalyst is regenerated under the action of the steam and heat is released. At the same time, the regeneration furnace is heated by the regeneration furnace heating device to maintain the regeneration furnace temperature at 800-900°C. At this time, the adsorbent desorbs CO2 at high temperature. The regenerated catalyst and desorbed adsorbent then react with steam to form a gas-solid mixture, which enters the regeneration furnace cyclone separator. In step S6, the gas-solid mixture is separated by the cyclone separator of the regeneration furnace, and the CO2-rich gas enters the gas pipeline through the CO2-rich outlet. The catalyst and adsorbent binary particles fall into the dense phase area at the bottom, and then mix with the adsorbent delivered by the adsorbent feeding device and enter the reforming hydrogen production furnace through the return valve.

[0011] As a preferred embodiment of the present invention, the components of the biomass gas include: CO, CO2, H2O, CH4, small molecular hydrocarbons and tar.

[0012] As a preferred embodiment of the present invention, the catalyst includes a nickel-based artificial catalyst, a copper-based artificial catalyst, an iron-based artificial catalyst, iron ore, ilmenite, pyrolusite, steel slag and / or coal ash; and the adsorbent component includes limestone.

[0013] As a preferred embodiment of the present invention, the flow state control in step S2 includes: The catalyst particle size is smaller than that of the adsorbent, and the specific surface area is larger than that of the adsorbent. Through the particle grading of the catalyst and the adsorbent, the catalyst and the adsorbent in the fluidized binary particles have the same fluidization characteristic window; Regulate the catalyst / adsorbent ratio and adjust the catalyst and adsorbent ratio according to the catalytic reaction rate and adsorption rate; The reforming hydrogen production furnace is a dual fluidized bed, with a bubbling bed at the bottom and a fast bed at the top, both adopting a high-density circulating bed form; the regeneration furnace is a bubbling bed, the temperature is maintained at 800-900°C, the residence time of adsorbent particles in the regeneration furnace is >20s, the operating wind speed is >6 m / s, and the steam residence time is controlled at 6-10s; The reforming hydrogen production furnace is subjected to graded air distribution, and the primary air and the secondary air are respectively transported through the first steam pipeline and the second steam pipeline, and the ratio of the primary air and the secondary air is adjusted to achieve graded air distribution.

[0014] As a preferred embodiment of the present invention, the catalyst particle size is 30-60 μm, the adsorbent particle size is 80-150 μm; the mass ratio of catalyst to adsorbent is 1:2 to 1:10; the particle concentration in the double fluidized bed of the reforming hydrogen production furnace reaches 30 kg / m 3 Above, the circulation flow rate reaches 100-300 kg / m 2 ·s; the primary air ratio is 30~70%.

[0015] As a preferred embodiment of the present invention, the H2 content in the hydrogen-rich synthesis gas is ≥90 vol.%.

[0016] As a preferred embodiment of the present invention, the CO 2 enrichment concentration in the CO 2 rich gas is ≥95 vol.%.

[0017] The technical solution provided by the embodiment of the present invention has the following beneficial effects: The fluidized bed adsorption enhanced biomass reforming hydrogen production method and system provided in the present application produces high value-added chemical raw materials and fine chemicals such as biomass green carbon, green hydrogen and green methanol from carbon-neutral fuel biomass through a coupled water electrolysis hydrogen production process, thereby realizing clean, efficient and diversified conversion of biomass. The flow state of the dual fluidized bed is regulated by particle grading, fluidized bed structure optimization and graded air distribution, so that the binary heterogeneous particles are evenly mixed in the dual fluidized bed system, avoiding damage to the fluidized state caused by binary particle flow stratification, while reducing the loss of catalyst and adsorbent caused by inter-particle wear; the promotion of the reforming hydrogen production process by binary particle mixing includes the adsorbent adsorbing CO2 to move the reaction to the right to improve the hydrogen production efficiency and the catalytic effect of the catalyst on the reaction, avoiding The problem of complex and high cost of preparing bifunctional catalysts is avoided; at the same time, the binary heterogeneous particles also play a role in regulating the reaction atmosphere, and the spatiotemporal evolution of the flow state of the binary particles can effectively improve the reaction process; the biomass gas and biomass green carbon produced by biomass pyrolysis and gasification are separated to avoid the ash in the biomass carbon causing poisoning and deactivation of the catalyst in the reforming hydrogen production process; steam is used as fluidizing air and loosening air to avoid the introduction of nitrogen to dilute the hydrogen-rich synthesis gas when using air, and the addition of steam can reduce the impact of carbon deposition on the catalyst; an efficient fractionation and conversion process route for agricultural biomass is constructed, with the H2 content of the hydrogen-rich synthesis gas ≥90%, and the CO2 enrichment concentration ≥95%. The continuous operation time and reliability of the system are improved by 25% compared with the existing technology.

[0018] Of course, it is not necessary to achieve all of the advantages described above simultaneously in order to implement any product or method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 Schematic diagram of the structure of the fluidized bed adsorption-enhanced biomass reforming hydrogen production system according to an embodiment of the present invention; Figure 2 This is a flow chart of the fluidized bed adsorption-enhanced biomass reforming hydrogen production method described in an embodiment of the present invention.

[0021] Description of reference numerals: 1. Biomass pyrolysis-gasification device; 100. Pyrolysis gasifier; 101. Biomass feeding device; 102. Gasifier pure oxygen pipeline; 103. Gasifier steam pipeline; 104. Biochar outlet; 105. Biomass gas pipeline; 2. Reforming hydrogen production device; 200. Reforming hydrogen production furnace; 201. Catalyst feeding device; 202. Reforming hydrogen production furnace heating device; 203. First steam pipeline; 204. Second steam pipeline; 205. Reforming furnace cyclone separator; 206. Reforming Furnace return valve; 207, reforming furnace return valve steam pipeline; 208, hydrogen-rich synthesis gas outlet; 209, hydrogen separation and purification device; 210, hydrogen outlet; 3, regeneration device; 300, regeneration furnace; 301, adsorbent feeding device; 302, regeneration furnace steam pipeline; 303, regeneration furnace pure oxygen inlet; 304, regeneration furnace cyclone separator; 305, rich CO2 outlet; 306, regeneration furnace return valve; 307, regeneration furnace return valve steam pipeline; 308, regeneration furnace heating device. DETAILED DESCRIPTION

[0022] After discovering the above-mentioned problems, the inventors of this application conducted a detailed study of existing biomass hydrogen production technologies. This research found that in the process of biomass reforming hydrogen production using catalysts, bifunctional catalysts are commonly used to simultaneously catalyze the reforming process while adsorbing. However, bifunctional catalysts are often complex to prepare and expensive. Furthermore, fluidized bed reactors suffer from severe particle attrition and consumption. The active sites on the particle surface are easily lost during operation, causing the material to lose its catalytic activity. Furthermore, the expensive bifunctional catalyst requires large quantities of refills to the reactor, increasing both process complexity and cost. In the biomass reforming hydrogen production process, there is also a mismatch between the catalytic reaction and the adsorptive reforming reaction. This mismatch between the catalytic and adsorptive reforming reactions is one of the key bottlenecks restricting efficient and stable operation. When the adsorbent reaction rate is slower than the catalytic reaction rate, the CO2 generated by the catalytic reaction cannot be promptly adsorbed by the adsorbent, resulting in product accumulation, a shift in the reaction equilibrium, and reduced H2 yield. Catalysts and adsorbents made of dissimilar materials often differ significantly in thermal stability, mechanical strength, and thermal expansion coefficient, which can easily lead to particle breakage, attrition, or sintering. In addition, biomass gas contains a large amount of CO, CH4 and certain heavy hydrocarbons or tar components. Driven by thermodynamic properties at high temperatures, it is easy to undergo cracking reactions to produce H2 and carbon, which cover the catalyst surface, resulting in the blocking of metal active sites such as Ni, Fe, and Co, causing carbon deposition and deactivation of the catalyst; carbon deposition may also cause problems such as particle agglomeration, flow deterioration, and repeated regeneration in the reactor, affecting the stable operation of the fluidized bed system.

[0023] It should be noted that the defects existing in the solutions in the above-mentioned prior art are the results obtained by the inventors after practice and careful research. Therefore, the discovery process of the above-mentioned problems and the solutions proposed in the embodiments of the present invention below for the above-mentioned problems should all be the contributions made by the inventors to the present invention in the process of the invention.

[0024] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations. It should be noted that the embodiments of the present invention and the features in the embodiments can also be combined with each other in the absence of conflict.

[0025] It should be noted that similar reference numerals and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures. In the description of the present invention, the terms "first," "second," "third," "fourth," etc. are used only to distinguish the description and are not to be understood as indicating or implying relative importance.

[0026] After the above in-depth analysis, an embodiment of the present invention provides a fluidized bed adsorption-enhanced biomass reforming hydrogen production method and system. After the biomass particles are pyrolyzed and gasified in a biomass pyrolysis-gasification device, the generated biomass gas enters the reforming hydrogen production device. Under the condition of uniform mixing of the adsorbent and catalyst binary particles, CO2 is adsorbed and CH4, CO, tar, etc. are catalytically converted to produce hydrogen-rich synthesis gas. Afterwards, the binary mixed particles enter the regeneration device for CO2 desorption and catalyst regeneration. This application adopts flow control methods such as particle size grading, structural optimization, and graded air distribution to avoid the damage to the fluidized state caused by binary particle flow stratification and reduce the loss of catalysts and adsorbents caused by inter-particle wear; at the same time, the direct use of binary particles can avoid the complex and high cost problems of preparing bifunctional catalysts; the generated biomass gas and biomass green carbon are decoupled to avoid the ash in the biomass carbon poisoning and inactivation of the reforming hydrogen production catalyst, and at the same time obtain high-value biomass green carbon; the constructed biomass efficient fractionation conversion process route can achieve a hydrogen-rich synthesis gas H2 content ≥90%, a CO2 enrichment concentration ≥95%, and realize clean and efficient multi-dimensional conversion of biomass.

[0027] like Figure 1 As shown, the fluidized bed adsorption enhanced biomass reforming hydrogen production system includes: a biomass pyrolysis-gasification device 1, a reforming hydrogen production device 2, a regeneration device 3 and connecting pipelines.

[0028] Among them, the biomass pyrolysis-gasification device 1 includes a pyrolysis gasification furnace 100, a biomass feeding device 101, a gasification furnace pure oxygen pipeline 102, a gasification furnace steam pipeline 103, a biomass charcoal outlet 104, and a biomass gas pipeline 105; the biomass feeding device 101 is connected to the top of the pyrolysis gasification furnace 100, and the gasification furnace pure oxygen pipeline 102 and the gasification furnace steam pipeline 103 are connected to the middle and upper part of the pyrolysis gasification furnace 100; the biomass charcoal outlet 104 is located at the bottom of the pyrolysis gasification furnace 100, and the biomass gas pipeline 105 is connected from the bottom of the pyrolysis gasification furnace 100 to the bottom of the reforming hydrogen production furnace 200 of the reforming hydrogen production device 2.

[0029] The reforming hydrogen production device 2 includes a reforming hydrogen production furnace 200, a catalyst feeding device 201, a reforming furnace heating device 202, a first steam pipeline 203, a second steam pipeline 204, a reforming furnace cyclone separator 205, a reforming furnace return valve 206, a reforming furnace return valve steam pipeline 207, a hydrogen-rich synthesis gas outlet 208, a hydrogen separation and purification device 209, and a hydrogen outlet 210; wherein, the reforming hydrogen production furnace 200 is a thin and tall double-bed structure with a height-to-diameter ratio>10, the bottom dense phase zone is a bubbling bed, the middle dilute phase zone and the upper dilute phase zone are fast beds, and the reforming furnace heating device 202 is provided outside the furnace body of the upper dilute phase zone; the first steam pipe is provided at the bottom of the furnace body Road 203, a second steam pipeline 204 is set in the middle, the first steam pipeline 203 enters the bottom dense phase zone as primary air, and the second steam pipeline 204 enters the middle dilute phase zone as secondary air; the catalyst feeding device 201 is connected to the middle and lower part of the reforming hydrogen production furnace 200; the top outlet of the reforming hydrogen production furnace 200 is connected to the reforming furnace cyclone separator 205, the bottom outlet of the reforming furnace cyclone separator 205 is connected to the reforming furnace return valve 206 and the reforming furnace return valve steam pipeline 207, the top outlet of the reforming furnace cyclone separator 205 is connected to the hydrogen-rich synthesis gas outlet 208, and then connected to the hydrogen separation and purification device 209 and the hydrogen outlet 210.

[0030] The regeneration device 3 includes a regeneration furnace 300, an adsorbent feeding device 301, a regeneration furnace steam pipeline 302, a regeneration furnace pure oxygen inlet 303, a regeneration furnace cyclone separator 304, a CO2-rich outlet 305, a regeneration furnace return valve 306, a regeneration furnace return valve steam pipeline 307, and a regeneration furnace heating device 308; wherein, the reforming hydrogen production furnace return valve 206 is connected to the regeneration furnace 300, the adsorbent feeding device 301 enters from the middle and lower part of the regeneration furnace 300, and the regeneration furnace steam pipeline 302 and the regeneration furnace are connected. The furnace pure oxygen inlet 303 is connected to the bottom of the regeneration furnace 300; the top of the regeneration furnace 300 is connected to the regeneration furnace cyclone separator 304, and a CO2-rich outlet 305 is provided on the top of the regeneration furnace cyclone separator 304; the lower part of the regeneration furnace 300 is connected to the regeneration furnace return valve 306, and the bottom of the regeneration furnace return valve 306 is connected to the regeneration furnace return valve steam pipeline 307; the outlet of the regeneration furnace return valve 306 is connected to the lower part of the reforming hydrogen production furnace 200; a regeneration furnace heating device 308 is provided on the outside of the regeneration furnace 300.

[0031] The system may further include a steam generator connected to the treated water pipeline for providing steam to the gasifier steam pipeline 103, the first steam pipeline 203 of the reforming hydrogen production furnace, the second steam pipeline 204, the reforming furnace return valve steam pipeline 207, the regeneration furnace steam pipeline 302, and the regeneration furnace return valve steam pipeline 307.

[0032] Based on the fluidized bed adsorption enhanced biomass reforming hydrogen production system, the embodiment of the present invention also provides a fluidized bed adsorption enhanced biomass reforming hydrogen production method; Figure 2 As shown, the method includes: In step S1, the formed biomass particles are fed from the biomass feeding device into the pyrolysis and gasification furnace of the biomass pyrolysis-gasification device, oxygen is introduced into the pure oxygen pipeline of the gasification furnace, steam is introduced into the steam pipeline of the gasification furnace, and the formed biomass particles are pyrolyzed and gasified to generate biomass gas and biomass charcoal; the biomass gas is transported to the reforming hydrogen production furnace through the biomass gas pipeline, and the biomass charcoal is output outside the system and collected for subsequent use.

[0033] In this step, the biomass gas pipeline temperature is maintained at 400-500°C; the remaining solid phase component biochar after gasification is collected through the biochar outlet. The components of the biomass gas include: CO, CO2, H2O, CH4, small molecular hydrocarbons and tar.

[0034] In this step, biomass is pyrolyzed and gasified in a pyrolysis gasifier to obtain biomass gas and biochar, and the biomass gas and biochar are decoupled in the gasifier and transported to different pipelines respectively to prevent the biochar from entering the reforming hydrogen production process, thereby avoiding the ash therein causing poisoning and deactivation of the reforming hydrogen production catalyst, and at the same time obtaining high-value biochar.

[0035] In step S2, the catalyst particles are transported from the catalyst feeding device to the dense phase area in the reforming hydrogen production furnace; the adsorbent particles are transported from the adsorbent feeding device to the regeneration furnace, and then enter the dense phase area in the reforming hydrogen production furnace through the regeneration furnace return valve to mix with the catalyst particles to form binary particles; steam is input into the reforming hydrogen production furnace through the first steam pipeline and the second steam pipeline to make the catalyst and adsorbent binary particles flow in gas-solid two-phase and mix evenly, and the flow state of the fluidized binary particles is regulated; the reforming hydrogen production furnace is heated by the reforming hydrogen production furnace heating device to maintain the temperature at 600~750℃.

[0036] In this step, the catalyst and adsorbent binary particles, on the one hand, catalyze the reaction, and on the other hand, the adsorbent absorbs the generated carbon dioxide gas, which promotes the reaction to the right, improves the hydrogen production efficiency, and absorbs the released heat to provide it to the reaction process; in addition, the catalyst and the adsorbent are in a mixed state of binary particles, rather than a dual-functional single particle state, avoiding the problem of high cost of preparing the catalyst and adsorbent and replenishing them after consumption.

[0037] Preferably, the catalyst particles are made of artificial catalysts such as nickel-based, copper-based, and iron-based catalysts, or natural catalysts such as iron ore, ilmenite, pyrolusite, steel slag, and coal ash. The adsorbent particles include limestone.

[0038] In this step, the flow state control includes particle size distribution, binary ratio, bed structure, and graded air distribution. Specifically, it includes: The catalyst particle size is smaller than that of the adsorbent, and the specific surface area is larger than that of the adsorbent. Through the particle grading of the catalyst and adsorbent, the catalyst and adsorbent in the fluidized binary particles have the same fluidization characteristic window, thereby achieving the same flow state and achieving uniform mixing, thereby avoiding the damage to the fluidization state caused by binary particle flow stratification or uneven fluidization, while reducing the loss of catalyst and adsorbent caused by inter-particle wear. Preferably, the catalyst particle size is 30-60 μm and the adsorbent particle size is 80-150 μm; by controlling the binary particle size matching, the catalytic reaction and reforming reaction rates and the heat and mass transfer process are coordinated to improve the overall hydrogen production efficiency; Regulate the catalyst / adsorbent ratio, adjusting the catalyst to adsorbent ratio based on the catalytic reaction rate and adsorption rate. Preferably, the catalyst:adsorbent ratio is 1:2 to 1:10 (mass ratio). The reforming hydrogen production furnace is a double fluidized bed, with a bubbling bed at the bottom and a fast bed at the top, both of which adopt high-density circulating bed form; preferably, the particle concentration in the bed reaches 30 kg / m 3 Above, the circulation flow rate reaches 100-300 kg / m 2 ·s, and the temperature is maintained at 600~750℃; this allows the catalyst and adsorbent binary particles to reflux at high speed, thereby maintaining high-density and stable operation of the bed; the regeneration furnace is a bubbling bed, the temperature is maintained at 800~900℃, the adsorbent particles stay in the regeneration furnace for >20s, the operating wind speed is >6 m / s, and the steam residence time is controlled at 6-10 s; The reforming hydrogen production furnace is equipped with a graded air distribution system. Primary and secondary air are delivered through the first and second steam lines, respectively. The ratio of primary and secondary air is adjusted to achieve graded air distribution, thereby controlling the atmosphere distribution and fluidization state within the furnace, reducing local overheating of the catalyst, and simultaneously achieving vigorous fluidization and cleaning of particles to reduce carbon deposition. Preferably, the primary air ratio is 30-70%, and the secondary air ratio is 70-30%.

[0039] In step S3, the biomass gas is introduced into the reforming hydrogen production furnace and mixed with the fluidized binary particles to form a gas-solid mixture; in the gas-solid mixture, the biomass gas is converted into H2, CO, and CO2 under the action of the catalyst; the CO2 generated by adsorption by the adsorbent is converted into calcium carbonate, which further promotes the conversion of the biomass gas; the final gas-solid mixture enters the reforming furnace cyclone separator.

[0040] In this step, the chemical reaction of biomass gas under the action of catalyst includes: (1) (2) (3) (4) (5) Wherein, Equation (3) is the decomposition reaction of the tar component in the biomass gas under the action of the catalyst. The catalyst converts the tar in the biomass gas into H2, thereby reducing the carbon deposition problem.

[0041] In step S4, the gas-solid mixture is separated by the reformer cyclone separator, and the separated hydrogen enters the hydrogen separation and purification device through the hydrogen-rich synthesis gas outlet, and the purified hydrogen then enters the hydrogen pipeline through the hydrogen outlet; the separated catalyst and adsorbent binary particles enter the regeneration furnace through the reformer return valve.

[0042] In this step, the H2 content in the hydrogen-rich synthesis gas is ≥90 vol.%.

[0043] During the biomass gas reaction process of the reforming hydrogen production furnace, the catalyst and adsorbent will gradually deactivate. In this embodiment, steam is introduced through the steam pipeline of the reforming furnace return valve, and the loose air volume in the return valve is adjusted to enhance the sweeping ability of the particles at the outlet of the reforming hydrogen production furnace cyclone separator, accelerate the carrying speed of the inactivated particles, and make the fine, inactivated particles be blown away from the system with the air flow. In response to the problem of catalyst or adsorbent particles in the reaction process, it is proposed to achieve selective discharge by adjusting the separation efficiency of the reforming hydrogen production furnace cyclone separator and the return air operation of the reforming hydrogen production device return valve in this step, so that the fine particles are blown out and the large particles cannot be blown away by this wind, so that the large particles remain in the system.

[0044] In step S5, the binary particles of catalyst and adsorbent enter the dense phase zone in the middle of the regeneration furnace, and steam is introduced into the steam pipeline of the regeneration furnace to put the binary particles in a bubbling bed flow state; at the same time, the catalyst is regenerated under the action of steam and heat is released. At the same time, the regeneration furnace is heated by the regeneration furnace heating device to maintain the temperature of the regeneration furnace at 800~900℃; at this time, the adsorbent desorbs CO2 at high temperature; the regenerated catalyst and the desorbed adsorbent then generate a gas-solid mixture with steam and enter the regeneration furnace cyclone separator.

[0045] In step S6, the gas-solid mixture is separated by the cyclone separator of the regeneration furnace, and the CO2-rich gas enters the gas pipeline through the CO2-rich outlet. The catalyst and adsorbent binary particles fall into the dense phase area at the bottom, and then mix with the adsorbent delivered by the adsorbent feeding device and enter the reforming hydrogen production furnace through the return valve.

[0046] In this step, the CO2 enrichment concentration in the CO2-rich gas is ≥95 vol.%. The CO2-rich gas at the CO2-rich outlet and the hydrogen-rich synthesis gas at the hydrogen-rich synthesis gas outlet can enter the methanol synthesis tower to synthesize high-value industrial raw material methanol, or can be used in other industries requiring hydrogen or CO2 gas.

[0047] The regeneration furnace cyclone separator in this step, like the reforming furnace cyclone separator, is also provided with a regeneration furnace return valve steam pipeline. By adjusting the loose air volume in the return valve, the blowing capacity of the particles at the outlet of the regeneration furnace cyclone separator is enhanced to complete the material circulation within the system.

[0048] It can be seen that the fluidized bed adsorption-enhanced biomass gas reforming hydrogen production method and system provided in the embodiments of the present invention enable the catalytic reaction and adsorption reforming behavior to be carried out in coordination under different flow states, thereby improving the hydrogen production efficiency; the binary heterogeneous particles also play a role in regulating the reaction atmosphere, and the spatiotemporal evolution of the flow state of the binary particles can effectively promote the reaction process; realize the efficient recycling and utilization of the adsorbent and catalyst; promote particle turnover and distribution through flow state regulation, reduce the problem of catalyst carbon deposition; and reduce the cost of raw materials at the same time.

[0049] The above description is only a preferred embodiment of the present invention and an explanation of the technical principles used. It is not intended to limit the scope of the invention to be protected, but merely represents a preferred embodiment of the present invention. Those skilled in the art should understand that the scope of the invention involved in the present invention is not limited to the technical solutions formed by a specific combination of the above-mentioned technical features, but should also cover other technical solutions formed by any combination of the above-mentioned technical features or their equivalent features without departing from the inventive concept. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative work shall fall within the scope of protection of the present invention.

Claims

1. A fluidized bed adsorption enhanced biomass reforming hydrogen production system, characterized in that: The system includes: a biomass pyrolysis-gasification device, a reforming hydrogen production device, a regeneration device and connecting pipelines; Among them, in the biomass pyrolysis-gasification device, the biomass feeding device is connected to the top of the pyrolysis gasification furnace, and the gasification furnace pure oxygen pipeline and the gasification furnace steam pipeline are connected to the middle and upper part of the pyrolysis gasification furnace; the biomass char outlet is located at the bottom of the pyrolysis gasification furnace, and the biomass gas pipeline is set at the bottom of the pyrolysis gasification furnace and connected to the bottom of the reforming hydrogen production furnace; In the reforming hydrogen production device, the reforming hydrogen production furnace has a tall and thin double-bed structure with a height-to-diameter ratio of >10. The bottom dense phase zone is a bubbling bed, the middle dilute phase zone and the upper dilute phase zone are fast beds, and a reforming furnace heating device is installed outside the furnace body of the upper dilute phase zone; a first steam pipeline is installed at the bottom of the furnace body, and a second steam pipeline is installed in the middle; the catalyst feeding device is connected to the middle and lower part of the reforming hydrogen production furnace; the top of the reforming hydrogen production furnace is connected to the reforming furnace cyclone separator and is also provided with a hydrogen-rich synthesis gas outlet; the bottom outlet of the reforming furnace cyclone separator is connected to the reforming furnace return valve, and the bottom of the reforming furnace return valve is provided with a reforming furnace return valve steam pipeline; the reforming furnace return valve is connected to the regeneration furnace; In the regeneration device, an adsorbent feeding device is provided in the middle and lower part of the regeneration furnace, a regeneration furnace steam pipeline and a regeneration furnace pure oxygen inlet are provided at the bottom, the top is connected to the regeneration furnace cyclone separator, and a regeneration furnace heating device is provided outside the furnace body; a rich CO2 outlet is provided at the top of the regeneration furnace cyclone separator; a regeneration furnace return valve is provided at the lower part of the regeneration furnace, and a regeneration furnace return valve steam pipeline is provided at the bottom of the regeneration furnace return valve; the regeneration furnace return valve outlet is connected to the lower part of the reforming hydrogen production furnace.

2. The system according to claim 1, wherein: The system also includes a steam generator connected to the treated water pipeline for providing steam to the gasifier steam pipeline, the first steam pipeline, the second steam pipeline, the reformer return valve steam pipeline, the regenerator steam pipeline and the regenerator return valve steam pipeline.

3. The system according to claim 1, wherein: The temperature of the biomass gas pipeline is maintained at 400-500°C; the temperature of the reforming hydrogen production furnace is maintained at 600-750°C; and the temperature of the regeneration furnace is maintained at 800-900°C.

4. A fluidized bed adsorption-enhanced biomass reforming hydrogen production method, characterized in that: The method is implemented based on the system according to any one of claims 1 to 3, and specifically includes: Step S1: feeding the formed biomass particles into a pyrolysis gasification furnace from a biomass feeding device, introducing oxygen into the pure oxygen pipeline of the gasification furnace, and introducing steam into the steam pipeline of the gasification furnace; the formed biomass particles undergo pyrolysis and gasification in the gasification furnace to generate biomass gas and biochar; the biomass gas is transported to the reforming hydrogen production furnace through the biomass gas pipeline, and the biochar is output outside the system for collection and subsequent use; Step S2: transporting the catalyst particles from the catalyst feeding device to the dense phase area in the reforming hydrogen production furnace; transporting the adsorbent particles from the adsorbent feeding device to the regeneration furnace, and then entering the dense phase area in the reforming hydrogen production furnace through the regeneration furnace return valve to mix with the catalyst particles to form binary particles; inputting steam into the reforming hydrogen production furnace through the first steam pipeline and the second steam pipeline to make the catalyst and adsorbent binary particles flow in gas-solid two-phase and mix evenly, and controlling the flow state of the fluidized binary particles; heating the reforming hydrogen production furnace by the reforming hydrogen production furnace heating device to maintain the temperature at 600-750°C; In step S3, the biomass gas is introduced into the reforming hydrogen production furnace and mixed with the fluidized binary particles to form a gas-solid mixture; in the gas-solid mixture, the biomass gas is converted into H2, CO, and CO2 under the action of the catalyst; the CO2 generated by adsorption by the adsorbent is converted into calcium carbonate, further promoting the conversion of the biomass gas; the final gas-solid mixture enters the reforming furnace cyclone separator; In step S4, the gas-solid mixture is separated by a cyclone separator in the reforming furnace, and the separated hydrogen enters the hydrogen separation and purification device through the hydrogen-rich synthesis gas outlet. The purified hydrogen then enters the hydrogen use pipeline through the hydrogen outlet; the separated catalyst and adsorbent binary particles enter the regeneration furnace through the reforming furnace return valve; In step S5, the catalyst and adsorbent binary particles enter the dense phase zone in the middle of the regeneration furnace. Steam is introduced into the steam pipeline of the regeneration furnace to place the binary particles in a bubbling bed flow state. Simultaneously, the catalyst is regenerated under the action of the steam and heat is released. At the same time, the regeneration furnace is heated by the regeneration furnace heating device to maintain the regeneration furnace temperature at 800-900°C. At this time, the adsorbent desorbs CO2 at high temperature. The regenerated catalyst and desorbed adsorbent then react with steam to form a gas-solid mixture, which enters the regeneration furnace cyclone separator. In step S6, the gas-solid mixture is separated by the cyclone separator of the regeneration furnace, and the CO2-rich gas enters the gas pipeline through the CO2-rich outlet. The catalyst and adsorbent binary particles fall into the dense phase area at the bottom, and then mix with the adsorbent delivered by the adsorbent feeding device and enter the reforming hydrogen production furnace through the return valve.

5. The method according to claim 4, characterized in that The components of the biomass gas include: CO, CO2, H2O, CH4, small molecular hydrocarbons and tar.

6. The method according to claim 4, characterized in that The catalyst includes nickel-based artificial catalyst, copper-based artificial catalyst, iron-based artificial catalyst, iron ore, ilmenite, pyrolusite, steel slag and / or coal ash; and the adsorbent component includes limestone.

7. The method according to claim 4, characterized in that The flow state control in step S2 includes: The catalyst particle size is smaller than that of the adsorbent, and the specific surface area is larger than that of the adsorbent. Through the particle grading of the catalyst and the adsorbent, the catalyst and the adsorbent in the fluidized binary particles have the same fluidization characteristic window; Regulate the catalyst / adsorbent ratio and adjust the catalyst and adsorbent ratio according to the catalytic reaction rate and adsorption rate; The reforming hydrogen production furnace is a dual fluidized bed, with a bubbling bed at the bottom and a fast bed at the top, both adopting a high-density circulating bed form; the regeneration furnace is a bubbling bed, the temperature is maintained at 800-900°C, the residence time of adsorbent particles in the regeneration furnace is >20s, the operating wind speed is >6 m / s, and the steam residence time is controlled at 6-10s; The reforming hydrogen production furnace is subjected to graded air distribution, and the primary air and the secondary air are respectively transported through the first steam pipeline and the second steam pipeline, and the ratio of the primary air and the secondary air is adjusted to achieve graded air distribution.

8. The method according to claim 7, characterized in that The catalyst particle size is 30-60 μm, and the adsorbent particle size is 80-150 μm. The mass ratio of catalyst to adsorbent is 1:2 to 1:

10. The particle concentration in the double fluidized bed of the reforming hydrogen production furnace reaches 30 kg / m 3 Above, the circulation flow rate reaches 100-300 kg / m 2 ·s; the primary air ratio is 30~70%.

9. The method according to claim 4, characterized in that The H2 content in the hydrogen-rich synthesis gas is ≥90 vol.%.

10. The method according to claim 4, characterized in that The CO2 enrichment concentration in the CO2-rich gas is ≥95vol.%.

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