Biomass pyrolysis purification coupling reactor and biomass pyrolysis method

Abstract

The invention provides a biomass pyrolysis purification coupling reactor and a biomass pyrolysis method, and relates to the technical field of biomass pyrolysis gasification, the biomass pyrolysis purification coupling reactor comprises a fluidized bed reactor, a coupling purification separation assembly and a particle lifting conveying unit, the fluidized bed reactor comprises a reactor shell, a feed port and a gas distributor, the coupling purification and separation assembly comprises a cyclone separator, a built-in particle bed, a central exhaust pipe, a storage tank and a discharge structure, and the particle lifting and conveying unit is communicated with the dense-phase section and the storage tank. And the particle lifting and conveying unit is used for lifting and conveying pyrolysis products in the dense-phase section into the storage tank. The coke generated in the biomass pyrolysis process is used as the bed material of the built-in particle bed, so that not only is the recycling of solid-phase particles realized, but also the filtering and purifying capability and carrying heat of the particles are fully utilized.

Description

Technical Field

[0001] The invention relates to the technical field of biomass pyrolysis and gasification, and in particular to a biomass pyrolysis and purification coupling reactor and a biomass pyrolysis method. Background Art

[0002] Reducing the consumption of fossil fuels and developing renewable and sustainable energy have been identified as effective strategies to address the environmental pollution and climate change crises. Biomass resources, as the fourth largest energy system, are also one of the most important renewable energy sources for mankind. Compared with fossil fuels (such as natural gas, coal and oil), biomass not only has environmental advantages, but also has economic competitiveness. Approximately several billion tons of biomass waste are generated each year, of which crop straw is the main type of biomass waste, and about hundreds of millions of tons can be collected each year. Since biomass itself is generally considered to have zero carbon emissions, that is, the CO produced by the combustion or conversion of biomass 2 The CO absorbed during its growth 2 Therefore, the stored CO 2 After deducting the additional emissions in related processes, it has the characteristics of negative emissions.

[0003] Based on the inherent low calorific value of biomass, the production of syngas from biomass is more advantageous than using biomass to generate electricity / heat or to make solid fuels. Gasification refers to the conversion of solid fuels into substances such as gas mixtures, coke and condensable compounds (such as tar) through partial oxidation. This method is considered to be one of the most effective ways to convert the energy contained in biomass and is becoming one of the best alternative methods for the reuse of solid waste. During the gasification process, the gasification medium helps to decompose heavier solid hydrocarbons so that they can be converted into low molecular weight gases such as CO and H 2 .

[0004] Conventional biomass gasification technologies mainly include fixed bed (upward, downward, cross) and fluidized bed (bubbling fluidized bed, circulating fluidized bed) gasification reactors. In a fixed bed, a large amount of tar and coke will be produced due to the low and uneven heat and mass transfer between the biomass feedstock and the gasification medium. In contrast, the fluidized bed gasification reactor has good mixing and gas-solid contact, which improves the reaction rate and conversion efficiency. The efficient heat and mass transfer characteristics enable the fluidized bed to adapt to various types of biomass with different compositions and calorific values.

[0005] Chinese patent CN113684067A discloses a device for producing synthesis gas by gasification of biomass. Based on high-rate circulating fluidization and rapid heat dispersion technology, continuous and large-scale production can be achieved, but the process of the device is complicated and the energy consumption is high. Chinese patent CN111763524A discloses a system and method for three-stage enhanced pyrolysis gasification combining jetting and fluidization. This method realizes enhanced pyrolysis gasification and promotes raw material gasification by combining electromagnetic heating and additives, but can only gasify the above-mentioned biomass raw materials to reduce the emission of pollutants, and cannot effectively recover the carbon-containing resources in the biomass, resulting in a waste of resources. Patent CN112694918A discloses a composite gasification system of biomass pressurized fluidized bed gasification and cyclone cracking. This method combines biomass pressurized fluidized bed gasification with cyclone cracking, which can shorten the gasification reaction time, greatly improve the gasification intensity, and generate more combustible components. However, this method also cannot solve the problem of recycling pyrolysis waste, and additional heat recovery equipment is required to achieve inefficient heat circulation.

[0006] In summary, although the existing technology can meet the needs of biomass gasification to a certain extent, there is still room for improvement in terms of improving efficiency, reducing costs and enhancing environmental performance. Therefore, exploring more advanced and reasonable biomass gasification solutions is of great significance to promoting the development of a green and low-carbon economy. Summary of the invention

[0007] In order to overcome the above-mentioned defects of the prior art, the technical problem to be solved by the embodiments of the present invention is to provide a biomass pyrolysis purification coupling reactor and a biomass pyrolysis method, which are used to at least solve the problems of low gas production quality and high energy consumption in the existing biomass pyrolysis technology.

[0008] The above-mentioned object of the present invention can be achieved by adopting the following technical scheme. The present invention provides a biomass pyrolysis purification coupled reactor, comprising:

[0009] A fluidized bed reactor, the fluidized bed reactor comprising a reactor shell, a feed port arranged on the reactor shell, and a gas distributor, the inner space of the reactor shell is formed with a dense phase section and a dilute phase section from bottom to top, the gas distributor is arranged in the dense phase section, the gas distributor is used to input pyrolysis gas into the reactor shell, and the feed port is used to supply biomass raw materials into the dense phase section;

[0010] A coupled purification and separation component, the coupled purification and separation component comprising a cyclone separator arranged in the reactor shell, a built-in particle bed plugged into the cyclone shell of the cyclone separator, a central exhaust pipe plugged into the built-in particle bed, a storage tank arranged above the cyclone shell, and a discharge structure arranged below the built-in particle bed, the top end of the central exhaust pipe is arranged outside the reactor shell, the storage tank is communicated with the built-in particle bed, the storage tank is used to transport the solid-phase particle product to the built-in particle bed, the discharge structure is communicated with the built-in particle bed and is placed above the gas distributor, and the discharge structure is used to transport the pyrolysis coke after the purification reaction of the built-in particle bed to the dense phase section;

[0011] A particle lifting and conveying unit is connected to the dense phase section and the storage tank, and is used to lift and convey the pyrolysis products in the dense phase section to the storage tank.

[0012] In a preferred embodiment of the present invention, the biomass pyrolysis and purification coupling reactor also includes a discharge pipe and a feed pipe arranged on the reactor shell, the discharge pipe is used to connect to the dense phase section, the feed pipe is used to connect to the storage tank, and the particle lifting and conveying unit connects the discharge pipe and the feed pipe.

[0013] In a preferred embodiment of the present invention, the particle lifting and conveying unit includes a lifting pipe and a top collecting tank connected in sequence, and the lifting pipe is divided into a pre-lifting section and a lifting section from bottom to top, the lower end of the pre-lifting section is connected with the dense phase section through the discharge pipe, and the lower end of the pre-lifting section is provided with a conveying gas inlet, the lower end of the top collecting tank is connected with the storage tank through the conveying pipe, and the top outlet of the top collecting tank is provided with a small swirl.

[0014] In a preferred embodiment of the present invention, the built-in particle bed includes an inner wall of the particle bed and an outer wall of the particle bed, the inner wall of the particle bed and the outer wall of the particle bed are mutually arranged to form a sleeve-type sandwich structure, and a plurality of air flow holes are provided on the inner wall of the particle bed and the outer wall of the particle bed.

[0015] In a preferred embodiment of the present invention, the discharge structure includes a hopper and a discharge leg, the hopper is connected to the lower end of the built-in particle bed, the discharge leg is connected to the lower end of the hopper, and the bottom outlet of the discharge leg is placed in the dense phase section.

[0016] In a preferred embodiment of the present invention, an anti-backflow cone is provided at the lower end of the discharge leg, the radial dimension of the anti-backflow cone gradually increases from top to bottom, the anti-backflow cone is spaced from the bottom outlet of the discharge leg, and the pyrolysis solid phase products in the discharge leg can be discharged from the gap between the discharge leg and the anti-backflow cone.

[0017] In a preferred embodiment of the present invention, the biomass pyrolysis and purification coupling reactor further comprises a screw feeder, and the screw feeder is connected to the dense phase section to form the feed inlet.

[0018] The present invention provides a biomass pyrolysis method, which is implemented by using the aforementioned biomass pyrolysis purification coupled reactor, and specifically comprises the following steps:

[0019] Adding biomass raw materials into a fluidized bed reactor and introducing pyrolysis gas into the fluidized bed reactor to cause the biomass raw materials to undergo pyrolysis reaction;

[0020] The coarse gas product produced by the pyrolysis reaction enters the cyclone shell, and the solid phase particle product produced by the pyrolysis reaction enters the particle lifting and conveying unit;

[0021] Introducing a conveying gas into the particle lifting and conveying unit to lift the solid-phase particle product conveyed to the particle lifting and conveying unit to a storage tank, and then conveying the solid-phase particle product to the built-in particle bed via the storage tank;

[0022] The coarse gas product transported to the cyclone casing and the solid-phase particle product transported to the built-in particle bed undergo a purification reaction, and the gas-phase product and the solid-phase product after the purification reaction are transported to the central exhaust pipe and the discharge structure respectively.

[0023] In a preferred embodiment of the present invention, the fluidized bed reactor comprises a dense phase section and a dilute phase section, the superficial gas velocity in the dense phase section is 0.2 m / s to 1.3 m / s, and the superficial gas velocity in the dilute phase section is 0.05 m / s to 0.8 m / s.

[0024] In a preferred embodiment of the present invention, the biomass raw material includes a combination of one or more of straw, wood chips, coconut shells, corn stalks or waste rich in organic matter. Before being transported to the fluidized bed reactor, the biomass raw material is dried and molded to form particles with an equivalent particle size of less than 6 mm.

[0025] The technical solution of the present invention has the following significant beneficial effects:

[0026] When the biomass pyrolysis purification coupling reactor of the present invention is used, the coke produced in the biomass pyrolysis process is used as the bed material of the built-in particle bed, which not only realizes the recycling of solid particles, but also makes full use of the filtering and purification capacity and heat carrying capacity of these particles. The present invention can effectively reduce the tar concentration and ash content in the crude gas production by coordinating the fluidized bed reactor, the coupled purification separation component and the particle lifting and conveying unit, solves the problem of poor catalytic effect caused by the short contact time between tar and coke in the traditional fluidized bed reactor, and achieves the purpose of fine purification of the crude gas production.

[0027] The biomass pyrolysis and purification coupling reactor of the present invention can realize the close integration of tar reforming, coke pyrolysis and carbonization, and gas purification process, significantly improving the cleanliness and calorific value of the produced gas. Compared with the multi-stage process flow, it realizes the recycling of heat carried by the solid phase, reduces the use of fossil fuels and filter media / equipment, and can greatly reduce the operating cost.

[0028] In addition, crop straw, agricultural product processing residues, forests, organic solid waste, domestic garbage, etc. can all be used as biomass pyrolysis raw materials, making the present invention show a wide range of raw material adaptability and high gasification efficiency. In addition, the operating load of the biomass pyrolysis purification coupling reactor can be flexibly adjusted according to actual needs, and the key operating steps such as pyrolysis, gas-solid separation and loop sealing are integrated into one unit for execution, thereby simplifying the overall process flow, and the investment intensity and unit synthesis gas production cost have obvious advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] 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.

[0030] The accompanying drawings described herein are only for explanation purposes and are not intended to limit the scope of the present invention in any way. In addition, the shapes and proportional dimensions of the various components in the figures are only schematic, used to help understand the present invention, and are not specifically limited to the shapes and proportional dimensions of the various components of the present invention. Those skilled in the art can select various possible shapes and proportional dimensions to implement the present invention according to the teachings of the present invention.

[0031] Figure 1 A cross-sectional structural diagram of an embodiment of the biomass pyrolysis and purification coupling reactor of the present invention;

[0032] Figure 2 It is a structural schematic diagram of an embodiment of a cyclone separator inlet provided with air guide blades in the present invention;

[0033] Figure 3 A cross-sectional structural diagram of an embodiment of the particle lifting and conveying unit of the present invention having two groups.

[0034] Reference numerals in the above drawings:

[0035] 1. Fluidized bed reactor; 11. Dense phase section; 12. Dilute phase section;

[0036] 2. Coupled purification and separation components; 21. Cyclone separator inlet; 22. Cyclone housing; 23. Built-in particle bed; 24. Hopper; 25. Discharge legs; 26. Anti-reverse cone; 27. Central exhaust pipe; 28. Storage tank;

[0037] 3. Particle lifting and conveying unit; 31. Small cyclone; 32. Top collecting tank; 33. Feed pipe; 34. Lifting pipe; 35. Discharge pipe; 36. Pre-lifting section; 37. Lifting section;

[0038] 4. Gas distributor;

[0039] 5. Screw feeder. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Implementation Party 1

[0042] Please refer to Figures 1 to 3 As shown, a biomass pyrolysis purification coupling reactor is provided in an embodiment of the present invention, and the biomass pyrolysis purification coupling reactor includes a fluidized bed reactor 1, a coupled purification separation component 2 and a particle lifting and conveying unit 3. The fluidized bed reactor 1 includes a reactor shell, a feed port arranged on the reactor shell, and a gas distributor 4. The internal space of the reactor shell is formed with a dense phase section 11 and a dilute phase section 12 from bottom to top. The gas distributor 4 is arranged in the dense phase section 11. The gas distributor 4 is used to input pyrolysis gas into the reactor shell, and the feed port is used to supply biomass raw materials into the dense phase section 11.

[0043] The coupled purification and separation component 2 includes a cyclone separator arranged in a reactor shell, a built-in particle bed 23 inserted in the cyclone outer shell 22 of the cyclone separator, a central exhaust pipe 27 inserted in the built-in particle bed 23, a storage tank 28 arranged above the cyclone outer shell 22, and a discharge structure arranged below the built-in particle bed 23. The top end of the central exhaust pipe 27 is arranged outside the reactor shell, the storage tank 28 is connected to the built-in particle bed 23, and the storage tank 28 is used to transport the solid-phase particle product to the built-in particle bed 23. The discharge structure is connected to the built-in particle bed 23 and is placed above the gas distributor 4. The discharge structure is used to transport the pyrolysis coke after the purification reaction of the built-in particle bed 23 to the dense phase section 11.

[0044] The particle lifting and conveying unit 3 is connected to the dense phase section 11 and the storage tank 28 , and the particle lifting and conveying unit 3 is used to lift the pyrolysis products in the dense phase section 11 and convey them to the storage tank 28 .

[0045] Specifically, the built-in particle bed 23 is inserted from the upper end of the cyclone housing 22 into the cyclone housing 22 and is extended in the axial direction. In addition, the central exhaust pipe 27 is inserted from the upper end of the built-in particle bed 23 into the built-in particle bed 23 and is extended in the axial direction, and the central exhaust pipe 27 can be connected to the reactor shell to play a fixing role. The coupled purification separation component 2 is provided with a cyclone separator inlet 21 connected to the cyclone housing 22, and the coarse product gas can enter the cyclone housing 22 through the cyclone separator inlet 21.

[0046] Preferably, the aforementioned axial direction is the axial direction of the reactor shell, so that the cyclone shell 22, the built-in particle bed 23 and the central exhaust pipe 27 are roughly coaxially arranged in parallel, so that the cyclone shell 22, the built-in particle bed 23 and the central exhaust pipe 27 can be arranged at the center of the reactor shell.

[0047] By connecting the fluidized bed reactor 1, the coupled purification and separation component 2 and the particle lifting and conveying unit 3, a closed loop can be formed, which not only realizes the recycling of solid particles, but also fully utilizes the filtering and purification capacity and heat carrying capacity of these particles.

[0048] The cyclone separator inlet 21 is provided on the cyclone separator, and the cyclone separator inlet 21 is used to convey the gas into the cyclone casing 22, so that the gas and the solid particles are separated through the cyclone flow.

[0049] In an embodiment of the present invention, Figure 2 In the illustrated embodiment, the cyclone separator inlet 21 is provided with a plurality of guide blades, which are arranged in an axially spaced ring around the built-in particle bed 23 to form a swirling flow rotating around the axial direction of the built-in particle bed 23 .

[0050] Due to the different centrifugal forces exerted on the gas and solid particles, the larger fixed particles settle in the cyclone casing 22, while the pyrolysis gas and smaller solid particles enter the built-in particle bed 23, thereby completing the preliminary separation of the coarse pyrolysis gas and effectively reducing the space occupied by the coupled purification and separation component 2.

[0051] Of course, in other feasible embodiments, designers can adjust the specific structure of the cyclone separator according to usage requirements, and no specific limitation is made here.

[0052] In an embodiment of the present invention, the biomass pyrolysis purification coupling reactor also includes a discharge pipe 35 and a feed pipe 33 arranged on the reactor shell, the discharge pipe 35 is used to connect the dense phase section 11, the feed pipe 33 is used to connect the storage tank 28, and the particle lifting and conveying unit 3 connects the discharge pipe 35 and the feed pipe 33.

[0053] Specifically, the discharge pipe 35 is arranged at the middle and lower part of the reactor shell, the feed pipe 33 is arranged at the upper part of the reactor shell, and the particle lifting and conveying unit 3 is placed outside the reactor shell. The discharge pipe 35 is arranged downwardly inclined from the reactor shell to the particle lifting and conveying unit 3 to improve the feeding efficiency. In addition, the feed pipe 33 is arranged downwardly inclined from the particle lifting and conveying unit 3 to the reactor shell to improve the feeding efficiency.

[0054] By utilizing the discharge pipe 35 and the feed pipe 33 , the particle lifting and conveying unit 3 can be spaced apart from the reactor shell, thereby preventing the high temperature on the reactor shell from affecting the particle lifting and conveying unit 3 , which helps to improve the service life of the particle lifting and conveying unit 3 .

[0055] Further, in order to improve the lifting uniformity of the material, in an embodiment of the present invention, as Figure 3 In the embodiment shown, multiple groups of particle lifting and conveying units 3 are provided, and the multiple groups of particle lifting and conveying units 3 are arranged in a ring at intervals. Correspondingly, multiple discharge pipes 35 and feed pipes 33 are correspondingly provided.

[0056] By setting up multiple groups of particle lifting and conveying units 3, they can cooperate with each other to play a lifting role, so that the pyrolysis products can be evenly lifted and conveyed to the storage tank 28, which is beneficial to increasing the processing capacity of the fluidized bed reactor 1 and avoiding the problem of uneven distribution of pyrolysis products in the built-in particle bed 23, thereby improving the pyrolysis efficiency.

[0057] The designer can adjust the specific number of the particle lifting and conveying units 3 according to the use requirements, and no specific limitation is made here. For example, two groups of particle lifting and conveying units 3 are provided, and the two groups of particle lifting and conveying units 3 are symmetrically distributed.

[0058] In the embodiment of the present invention, the particle lifting and conveying unit 3 includes a lifting pipe 34 and a top collecting tank 32 connected in sequence. From bottom to top, the lifting pipe 34 is divided into a pre-lifting section 36 and a lifting section 37. The lower end of the pre-lifting section 36 is connected to the dense phase section 11 through a discharge pipe 35. The lower end of the pre-lifting section 36 is provided with a conveying gas inlet. The lower end of the top collecting tank 32 is connected to the storage tank 28 through a conveying pipe 33. The top outlet of the top collecting tank 32 is provided with a small swirl 31. Designers can adjust the specific structure of the lifting pipe 34 according to the use requirements, and no specific restrictions are made here.

[0059] By introducing conveying gas into the pre-lifting section 36, the solid-phase particle product conveyed to the particle lifting and conveying unit 3 can be lifted to the top collecting tank 32 and finally conveyed to the storage tank 28, and then the solid-phase particle product can be conveyed to the built-in particle bed 23 through the storage tank 28.

[0060] Furthermore, by providing a small cyclone 31 at the top outlet of the top collecting tank 32, the small cyclone 31 can perform a cyclone dust removal on the gas, thereby collecting small-size pyrolytic coke particles. The small cyclone 31 is a cyclone separator, which can perform a cyclone separation on the gas entering the top collecting tank 32, thereby reducing small-size pyrolytic coke particles in the gas, and the gas filtered by the small cyclone 31 can be discharged through the exhaust port of the small cyclone 31.

[0061] In an embodiment of the present invention, the built-in particle bed 23 includes an inner wall of the particle bed and an outer wall of the particle bed, which are mutually nested to form a sleeve-type sandwich structure, and a plurality of air flow holes are provided on the inner wall of the particle bed and the outer wall of the particle bed.

[0062] By arranging the inner wall of the particle bed and the outer wall of the particle bed in a sandwich configuration, a flow channel for the solid phase produced by the pyrolysis reaction of the biomass particles is formed between the inner wall of the particle bed and the outer wall of the particle bed.

[0063] Preferably, the inner wall and outer wall of the particle bed are made of Johnson net. In addition, the material of the inner wall and outer wall of the particle bed can be selected from carbon steel or stainless steel according to the characteristics of the biomass particles and their products, and no specific limitation is made here.

[0064] Specifically, the coarse product gas produced by the pyrolysis reaction enters the cyclone casing 22 , undergoes a purification reaction with the pyrolysis coke transported to the built-in particle bed 23 , and then the purified gas phase product is transported to the central exhaust pipe 27 .

[0065] In addition, the particle lifting and conveying unit 3 is connected between the fluidized bed reactor 1 and the storage tank 28. The pyrolytic coke conveyed to the particle lifting and conveying unit 3 is conveyed to the top collecting tank 32 through the lifting pipe 34, and the conveying air flow is discharged through the exhaust port of the small cyclone 31. The pyrolytic coke enters the built-in particle bed 23, and after the purification reaction, it re-enters the dense phase section 11 through the discharge structure.

[0066] In an embodiment of the present invention, the discharge structure includes a hopper 24 and a discharge leg 25 . The hopper 24 is connected to the lower end of the built-in particle bed 23 . The discharge leg 25 is connected to the lower end of the hopper 24 . The bottom outlet of the discharge leg 25 is placed in the dense phase section 11 .

[0067] Furthermore, an anti-backward cone 26 is provided at the lower end of the discharge leg 25, and the radial dimension of the anti-backward cone 26 gradually increases from top to bottom. The anti-backward cone 26 is spaced from the bottom outlet of the discharge leg 25, and the pyrolysis solid phase products in the discharge leg 25 can be discharged from the gap between the discharge leg 25 and the anti-backward cone 26.

[0068] By setting an anti-backflow cone 26 below the bottom outlet of the discharge leg 25, the anti-backflow cone 26 can avoid the problem of material backflow, and by controlling the gap size between the bottom outlet of the discharge leg 25 and the anti-backflow cone 26, the material discharge speed can also be controlled, thereby achieving a better use effect.

[0069] Designers can adjust the specific shape of the anti-backward cone 26 according to usage requirements. For example, the anti-backward cone 26 is roughly conical or frustum-shaped, and no specific limitation is made here.

[0070] In an embodiment of the present invention, the biomass pyrolysis and purification coupling reactor further comprises a screw feeder 5 , and the screw feeder 5 is connected to the dense phase section 11 to form a feed inlet.

[0071] The designer can adjust the specific model of the screw feeder 5 according to the use needs, and no specific restrictions are made here. Of course, in other feasible embodiments, the designer can adjust the structure of the feeding device according to the use needs, and no specific restrictions are made here.

[0072] Implementation Method 2

[0073] Please combine Figure 1 As shown, the present invention also discloses a biomass pyrolysis method, which is implemented by using the biomass pyrolysis purification coupling reactor as described in the first embodiment, and specifically includes the following steps:

[0074] Step 100: adding biomass raw materials into the fluidized bed reactor 1, and introducing pyrolysis gas into the fluidized bed reactor 1 to cause the biomass raw materials to undergo pyrolysis reaction;

[0075] Step 200: allowing the crude gas product produced by the pyrolysis reaction to enter the cyclone housing 22, and the solid phase particle product produced by the pyrolysis reaction to enter the particle lifting and conveying unit 3;

[0076] Step 300: introducing a conveying gas into the particle lifting and conveying unit 3 to lift the solid-phase particle product conveyed to the particle lifting and conveying unit 3 to the storage tank 28, and conveying the solid-phase particle product to the built-in particle bed 23 via the storage tank 28;

[0077] Step 400: The crude gas product delivered to the cyclone casing 22 and the solid-phase particle product delivered to the built-in particle bed 23 undergo a purification reaction, and the gas-phase product and the solid-phase product after the purification reaction are delivered to the central exhaust pipe 27 and the discharge structure, respectively.

[0078] Specifically, biomass raw materials are added to the fluidized bed reactor 1 through the screw feeder 5, and high-temperature pyrolysis gas is introduced into the fluidized bed reactor 1 through the gas distributor 4, so that the biomass raw materials undergo pyrolysis reaction in the reactor shell. The internal temperature of the fluidized bed reactor 1 rises rapidly to the pyrolysis and carbonization reaction temperature of the biomass particles, the cellulose in the biomass particles is thermally resolved to produce volatile substances (coarse gas) and tar, the lignin in the biomass particles is decomposed to produce coke particles, and the coarse gas with a large amount of tar and ash moves upward to the dilute phase section 12, and the coarse gas produced by the pyrolysis reaction enters the cyclone housing 22 through the cyclone separator inlet 21 of the coupled purification and separation component 2.

[0079] The pyrolytic coke produced by the pyrolysis reaction enters the pre-lifting section 36 through the discharge pipe 35, and the conveying gas is introduced into the pre-lifting section 36 to lift the pyrolytic coke transported to the particle lifting and conveying unit 3 to the top collecting tank 32, and finally transported to the storage tank 28 as the bed material of the built-in particle bed 23, and the pyrolytic coke particles with smaller particle size in the gas in the top collecting tank 32 are collected by the small cyclone 31.

[0080] The coarse product gas transported to the cyclone casing 22 and the pyrolytic coke transported to the built-in particle bed 23 undergo a purification reaction, and the fine ash is further filtered, the cleanliness and calorific value of the product gas are improved, and the high-quality product gas and pyrolytic coke of the purification reaction are transported to the central exhaust pipe 27 and the discharge leg 25 respectively, thereby realizing the recycling of heat carried by the solid phase.

[0081] In an embodiment of the present invention, the fluidized bed reactor 1 includes a dense phase section 11 and a dilute phase section 12, the superficial gas velocity in the dense phase section 11 is 0.2 m / s to 1.3 m / s, and the superficial gas velocity in the dilute phase section 12 is 0.05 m / s to 0.8 m / s.

[0082] By making the superficial gas velocity in the dense phase section 11 0.2 m / s to 1.3 m / s, a higher superficial gas velocity helps to suspend and transport solid particles and reduce the risk of blockage. In addition, by making the superficial gas velocity in the dilute phase section 12 0.05 m / s to 0.8 m / s, a lower superficial gas velocity helps to reduce energy consumption while maintaining a stable transportation process.

[0083] By properly controlling the superficial gas velocity of the dense phase section 11 and the dilute phase section 12, the performance of pneumatic conveying can be significantly improved, the operating cost can be reduced, and the safety and reliability of operation can be ensured. Of course, the designer can adjust the superficial gas velocity according to the use needs, and no specific numerical limit is imposed here.

[0084] In an embodiment of the present invention, the biomass raw material includes a combination of one or more of straw, wood chips, coconut shells, corn stalks or waste rich in organic matter. Before being transported to the fluidized bed reactor 1, the biomass raw material is dried and molded to form particles with an equivalent particle size of less than 6 mm.

[0085] By preprocessing biomass raw materials into small particles and controlling their particle size below 6 mm, not only can the reaction efficiency and energy utilization efficiency be improved, but also the fluidization performance can be improved, storage and transportation can be facilitated, and it can help extend equipment life and improve product quality. These advantages together improve the economy and feasibility of the entire process.

[0086] All articles and references disclosed, including patent applications and publications, are incorporated herein by reference for various purposes. The term "consisting essentially of ... " describing a combination should include determined elements, ingredients, parts or steps and other elements, ingredients, parts or steps that do not substantially affect the basic novel features of the combination. The use of the terms "comprising" or "including" to describe the combination of elements, ingredients, parts or steps here also contemplates the implementation method consisting essentially of these elements, ingredients, parts or steps. Here, by using the term "may", it is intended to illustrate that any attribute described that "may" includes is optional. Multiple elements, ingredients, parts or steps can be provided by a single integrated element, ingredient, part or step. Alternatively, a single integrated element, ingredient, part or step can be divided into separate multiple elements, ingredients, parts or steps. The disclosure "one" or "one" used to describe an element, ingredient, part or step is not said to exclude other elements, ingredients, parts or steps.

[0087] Each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can be referred to each other. The above embodiments are only for illustrating the technical concept and features of the present invention. The purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A biomass pyrolysis purification coupled reactor, characterized in that: include: A fluidized bed reactor, the fluidized bed reactor comprising a reactor shell, a feed port arranged on the reactor shell, and a gas distributor, the inner space of the reactor shell is formed with a dense phase section and a dilute phase section from bottom to top, the gas distributor is arranged in the dense phase section, the gas distributor is used to input pyrolysis gas into the reactor shell, and the feed port is used to supply biomass raw materials into the dense phase section; A coupled purification and separation component, the coupled purification and separation component comprising a cyclone separator arranged in the reactor shell, a built-in particle bed plugged into the cyclone shell of the cyclone separator, a central exhaust pipe plugged into the built-in particle bed, a storage tank arranged above the cyclone shell, and a discharge structure arranged below the built-in particle bed, the top end of the central exhaust pipe is arranged outside the reactor shell, the storage tank is communicated with the built-in particle bed, the storage tank is used to transport the solid-phase particle product to the built-in particle bed, the discharge structure is communicated with the built-in particle bed and is placed above the gas distributor, and the discharge structure is used to transport the pyrolysis coke after the purification reaction of the built-in particle bed to the dense phase section; A particle lifting and conveying unit is connected to the dense phase section and the storage tank, and is used to lift and convey the pyrolysis products in the dense phase section to the storage tank.

2. The biomass pyrolysis purification coupled reactor according to claim 1, characterized in that: The biomass pyrolysis and purification coupling reactor also includes a discharge pipe and a feed pipe arranged on the reactor shell, the discharge pipe is used to connect to the dense phase section, the feed pipe is used to connect to the storage tank, and the particle lifting and conveying unit connects the discharge pipe and the feed pipe.

3. The biomass pyrolysis purification coupled reactor according to claim 2, characterized in that: The particle lifting and conveying unit includes a lifting pipe and a top collecting tank connected in sequence. From bottom to top, the lifting pipe is divided into a pre-lifting section and a lifting section. The lower end of the pre-lifting section is connected to the dense phase section through the discharge pipe. The lower end of the pre-lifting section is provided with a conveying gas inlet. The lower end of the top collecting tank is connected to the storage tank through the conveying pipe, and the top outlet of the top collecting tank is provided with a small swirl.

4. The biomass pyrolysis purification coupled reactor according to claim 1, characterized in that: The built-in particle bed comprises an inner wall of the particle bed and an outer wall of the particle bed, the inner wall of the particle bed and the outer wall of the particle bed are mutually sleeved to form a sleeve-type sandwich structure, and a plurality of air flow holes are arranged on the inner wall of the particle bed and the outer wall of the particle bed.

5. The biomass pyrolysis purification coupled reactor according to claim 1, characterized in that: The discharge structure comprises a hopper and a discharge leg, wherein the hopper is communicated with the lower end of the built-in particle bed, the discharge leg is communicated with the lower end of the hopper, and the bottom outlet of the discharge leg is disposed in the dense phase section.

6. The biomass pyrolysis purification coupled reactor according to claim 5, characterized in that: An anti-backward cone is provided at the lower end of the discharge leg, and the radial dimension of the anti-backward cone gradually increases from top to bottom. The anti-backward cone is spaced from the bottom outlet of the discharge leg, and the pyrolysis solid phase products in the discharge leg can be discharged from the gap between the discharge leg and the anti-backward cone.

7. The biomass pyrolysis purification coupled reactor according to claim 1, characterized in that: The biomass pyrolysis and purification coupling reactor further includes a screw feeder, which is connected to the dense phase section to form the feed inlet.

8. A biomass pyrolysis method, characterized in that: The method is implemented by using a biomass pyrolysis purification coupled reactor as described in any one of claims 1 to 7, comprising the following steps: Adding biomass raw materials into a fluidized bed reactor and introducing pyrolysis gas into the fluidized bed reactor to cause the biomass raw materials to undergo pyrolysis reaction; The coarse gas product produced by the pyrolysis reaction enters the cyclone shell, and the solid phase particle product produced by the pyrolysis reaction enters the particle lifting and conveying unit; Introducing a conveying gas into the particle lifting and conveying unit to lift the solid-phase particle product conveyed to the particle lifting and conveying unit to a storage tank, and then conveying the solid-phase particle product to the built-in particle bed via the storage tank; The coarse gas product transported to the cyclone casing and the solid-phase particle product transported to the built-in particle bed undergo a purification reaction, and the gas-phase product and the solid-phase product after the purification reaction are transported to the central exhaust pipe and the discharge structure respectively.

9. The biomass pyrolysis method according to claim 8, characterized in that: The fluidized bed reactor comprises a dense phase section and a dilute phase section, wherein the superficial gas velocity in the dense phase section is 0.2 m / s to 1.3 m / s, and the superficial gas velocity in the dilute phase section is 0.05 m / s to 0.8 m / s.

10. The biomass pyrolysis method according to claim 8, characterized in that: The biomass raw materials include one or more combinations of straw, wood chips, coconut shells, corn stalks or organic-rich wastes. Before being transported to the fluidized bed reactor, the biomass raw materials are dried and molded to form particles with an equivalent particle size of less than 6 mm.

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