Device and method for coupling riser pyrolysis with fluidized bed gasification

Abstract

The invention discloses a device for coupling riser pyrolysis with fluidized bed gasification. The device comprises a solid powder feeding system, a pyrolysis-gasification reactor, a coarse particle separation system and a fine particle separation system, the solid powder feeding system is used for conveying pulverized coal with wide particle size conditions to the pyrolysis-gasification reactor; the pyrolysis-gasification reactor is used for carrying out pyrolysis and gasification reaction on raw materials; the pyrolysis-gasification reactor is coupled through equipment, two reactions of pulverized coal pyrolysis and semicoke gasification are achieved, raw materials are directly converted into raw gas containing solid semicoke and coal tar, the raw gas sequentially enters the coarse particle separation system and the fine particle separation system, and step-by-step efficient separation of solid particles is achieved; and the coarse particle separation system and the fine particle separation system are returned to the gasification section of the pyrolysis-gasification reactor for gasification reaction through a forced material returning measure. According to the invention, raw material feeding and efficient pyrolysis and gasification under a wide particle size condition are realized.

Description

Technical Field

[0001] This invention belongs to the field of efficient coal fractionation and utilization technology, specifically relating to a device and method for riser pyrolysis coupled fluidized bed gasification. Background Technology

[0002] In the existing technology field, significant progress has been made in the construction of the technical theoretical system and the promotion of industrialization in the development of clean and efficient conversion and utilization technologies adapted to low-rank coal.

[0003] For example, Shaanxi Coal Group has developed a dual-circulation rapid pyrolysis process (SM-SP) for low-rank pulverized coal gas solid heat carrier and a rapid pyrolysis process for conveying bed pulverized coal, which have entered the industrial implementation stage. Longcheng Group has developed a low-rank coal rotary bed low-temperature dry distillation technology. The clean coke yield of the industrial demonstration project is 61.65 wt%, and the coal tar yield is 9.63 wt%.

[0004] However, existing coal pyrolysis technologies that have been developed and industrialized still have many problems: First, they mainly rely on low-rank coal pyrolysis technology, which produces a large amount of coke powder with fine particle size, making storage, transportation, and utilization difficult; second, lump coal pyrolysis has low efficiency and low tar yield, while pulverized coal pyrolysis can increase the coal tar yield, but it also produces a large amount of dust that is difficult to collect, causing process blockage and making long-term operation difficult; third, the heat transfer medium mainly uses gaseous heat carriers or gas-solid heat carriers, resulting in serious heat loss, high energy consumption, and difficulty in comprehensively utilizing the generated raw coal gas.

[0005] How to effectively couple coal pyrolysis and gasification, and further improve the "safety, stability, longevity, full capacity and high quality" of the technology, is an important direction that needs to be broken through at present. Summary of the Invention

[0006] In order to overcome the defects of the existing technology, the purpose of this invention is to provide a device and method specifically involving riser pyrolysis coupled with fluidized bed gasification, which couples riser pyrolysis and fluidized bed gasification in a pyrolysis-gasification reactor, realizing feedstock feeding and efficient pyrolysis and gasification under a wide range of particle size conditions, and solving the practical problems of difficult utilization of coke powder, difficult separation of high-temperature gas and solid, and difficult recycling of coke powder in the pyrolysis process of raw coal.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A device for riser pyrolysis coupled fluidized bed gasification includes a solid powder feeding system, a pyrolysis-gasification reactor, a coarse particle separation system, and a fine particle separation system;

[0009] The solid feed system is used for feeding raw materials under a wide range of particle size conditions, expanding the range of pulverized coal feed particle size, and conveying pulverized coal under a wide range of particle size conditions to the pyrolysis-gasification reactor.

[0010] The pyrolysis-gasification reactor is used to pyrolyze and gasify the raw materials. Through equipment coupling, the pyrolysis-gasification reactor realizes two reactions, pyrolysis of pulverized coal and gasification of semi-coke, in one reactor, directly converting the raw materials into crude coal gas containing solid semi-coke and coal tar. The crude coal gas enters the coarse particle separation system and the fine particle separation system in sequence to achieve efficient separation of solid particles in stages.

[0011] The coarse particle separation system is used to capture coarse particles in the mixed gas generated by the pyrolysis-gasification reactor.

[0012] The fine particle separation system is used to capture fine particles in the mixed gas generated by the pyrolysis-gasification reactor.

[0013] The coarse particle separation system and the fine particle separation system are returned to the gasification section of the pyrolysis-gasification reactor for gasification reaction through forced return measures.

[0014] The solid powder feeding system consists of, from top to bottom, a raw material silo, a pressure lock silo, a spiral solid powder feeding device, and a feeding accelerator;

[0015] The bottom output of the raw material silo is divided into two paths, which are connected to the top input of the pressure lock chamber, the bottom output of the pressure lock chamber is connected to the input of the spiral solidification feeding device, and the output of the spiral solidification feeding device is connected to the input of the feeding accelerator.

[0016] The pyrolysis-gasification reactor includes a riser pyrolysis section, a transition connection section, and a fluidized bed gasification section. The input ends of the riser pyrolysis section and the fluidized bed gasification section are connected to the output end of the feed accelerator.

[0017] The riser pyrolysis section and the fluidized bed gasification section are coupled together via a transition section. Multiple risers are evenly distributed within the riser pyrolysis section, isolating it into an upward pyrolysis zone and a downward heat carrier zone. The transition section is equipped with upward and downward channels. Gasified coal gas from the fluidized bed gasification section carries solid particles through the upward channel into the upward pyrolysis zone, where it mixes and exchanges heat with the feed material, achieving rapid pyrolysis. The downward heat carrier zone facilitates the initial separation of solid particles from the pyrolysis section. The separated solid particles are returned to the fluidized bed gasification section via the downward channel of the transition section, achieving gasification of the returned solid particles. This configuration achieves temperature zoning of the pyrolysis and gasification processes in the pyrolysis-gasification reactor, coupling the pyrolysis of the raw material with the gasification of the semi-coke solid particles.

[0018] The spiral solid powder feeding device is connected to the solid powder inlet of the pyrolysis upward zone of the riser section via a feeding accelerator;

[0019] The riser pyrolysis section is equipped with 1 to 6 pyrolysis upward zones, which enable rapid pyrolysis reaction of the feed material. Each pyrolysis upward zone is equipped with an independent solid powder feeding system.

[0020] The top of the riser pyrolysis section is provided with a start-up feed port and a gas outlet. The gas outlet of the riser pyrolysis section is connected to the gas inlet of the coarse particle separator through a straight pipe section, and the gas outlet of the coarse particle separator is connected to the gas inlet of the fine particle separator through a straight pipe section.

[0021] The coarse particle separation system includes a coarse particle separator, a return material locking structure I, a return material mixer I, and a reinforced nozzle I arranged sequentially from top to bottom.

[0022] The input end of the coarse particle separator is connected to the output end of the pyrolysis-gasification reactor, the input end of the return material lock control structure I is connected to the solid output end of the coarse particle separator, the input end of the return material mixer I is connected to the output end of the return material lock control structure I, and the input end of the enhanced nozzle I is connected to the output end of the return material mixer I.

[0023] The coarse particle separator adopts a single-tube cyclone separation structure or a multi-tube cyclone separation structure or a series combination, and is designed and matched according to the feed particle size and the particle size of the solid particles at the output end of the pyrolysis-gasification reactor.

[0024] The return material locking structure I has a locking function, which realizes the buffering, pressurization, metering and conveying of coarse particles captured by the coarse particle separator;

[0025] The return material mixer I has a rapid feeding function to increase the feeding rate, enabling rapid conveying of coarse particles output from the return material locking structure I.

[0026] The fine particle separation system includes, from top to bottom, a fine particle separator, a return material locking structure II, a return material mixer II, and a reinforced nozzle II;

[0027] The input end of the fine particle separator is connected to the gas output end of the coarse particle separator, the input end of the return material locking structure II is connected to the solid output end of the fine particle separator, the input end of the return material mixer II is connected to the output end of the return material locking structure II, and the input end of the enhanced nozzle II is connected to the output end of the return material mixer II.

[0028] The fine particle separator adopts one or more of the following combinations in series: multi-tube cyclone separation structure, metal sintered filter element structure, ceramic sintered filter element structure, or bag filter dust collection filter element structure. The design and matching are based on the particle size of solid particles at the gas output end of the coarse particle separator, the system operating pressure, and the requirements of the downstream process for the solid content in the tar.

[0029] The return material locking structure II has a locking function, which realizes the buffering, pressurization, metering and conveying of fine particles captured by the fine particle separator;

[0030] The return material mixer II has a rapid feeding function that increases the feeding rate, enabling rapid conveying of fine particles output from the return material locking structure II.

[0031] The fluidized bed gasification section is symmetrically provided with four forced return ports I to IV. The enhanced nozzle I (12) is connected to the forced return port I, the enhanced nozzle II (16) is connected to the forced return port II, and the forced return ports III and IV are spare ports.

[0032] Forced return ports I to IV are located in the middle of the fluidized bed gasification section and are evenly distributed.

[0033] The internal components of the coarse particle separator and fine particle separator adopt one or more of the following combinations: single-tube cyclone separation structure, multi-tube cyclone separation structure, metal sintered filter element structure, ceramic sintered filter element structure, or bag filter element structure.

[0034] The coarse particle separator adopts a single-tube cyclone separation structure or a multi-tube cyclone separation structure or a series combination, and is designed and matched according to the feed particle size and the particle size of the solid particles at the output end of the pyrolysis-gasification reactor.

[0035] The fine particle separator adopts one or more of the following combinations in series: multi-tube cyclone separation structure, metal sintered filter element structure, ceramic sintered filter element structure, or bag filter dust collection filter element structure. The design and matching are based on the particle size of solid particles at the gas output end of the coarse particle separator, the system operating pressure, and the requirements of the downstream process for the solid content in the tar.

[0036] The top view of the arrangement of the pyrolysis-gasification reactor, coarse particle separator and fine particle separator is a right-angled triangle structure, and the included angle β between the pyrolysis-gasification reactor and the coarse particle separator ranges from 15° to 90°.

[0037] The gas outlet of the pyrolysis upward zone of the riser pyrolysis section is a rectangular opening with a size ratio of L (length):W (width) = 1:1 to 2:1 and L (length):H (height) = 1:1 to 1:4. The angle α between the rectangular opening and the horizontal direction is 0 to 60°.

[0038] The bottom of the transition section of the pyrolysis-gasification reactor is provided with 4 to 24 symmetrical natural return ports.

[0039] The bottom of the fluidized bed gasification section of the pyrolysis-gasification reactor is equipped with an air distribution plate, and the number of distributors on the air distribution plate is 10 to 300. Two ash discharge ports are arranged horizontally and symmetrically on the air distribution plate.

[0040] The particle size range of the solid powder in the spiral solid powder feeding device is 0.025mm to 20mm, and the feeding speed of the feeding accelerator is 3 to 15m / s.

[0041] The gas velocity in the fluidized bed gasification section is 0.8–5.5 m / s, and the gas velocity in the fluidized bed pyrolysis section is 5–25 m / s.

[0042] The average gas velocity at the gas inlet of the coarse particle separator is 20–35 m / s, and the average gas velocity at the gas inlet of the fine particle separator is 10–25 m / s.

[0043] The solid feed rate of the return mixer I and the return mixer II is 3 to 15 m / s.

[0044] The operating temperature of the riser pyrolysis section is 450–750°C, the operating temperature of the fluidized bed gasification section is 450–1150°C, the operating temperature of the coarse particle separator and the fine particle separator is >300°C, and the operating pressure of the coupling device is 0.1–5.0 MPa.

[0045] A method for riser pyrolysis coupled fluidized bed gasification includes the following implementation steps:

[0046] Step 1: System Hot Standby

[0047] The temperature of the riser pyrolysis section and fluidized bed gasification section of the pyrolysis-gasification reactor is increased to >300℃ by using a high-temperature flue gas oven, and the temperature of the coarse particle separator and fine particle separator is increased to over 300℃.

[0048] Step 2: Start the solid powder feeding system:

[0049] The raw material silo and pressurized lock silo continuously convey solid powder with a particle size range of 0.025mm to 20mm to the spiral solid powder feeding device. The feeding accelerator adjusts the feeding air velocity to 3 to 15m / s to quickly convey the solid powder to the pyrolysis section of the riser.

[0050] Step 3: Establish a loop:

[0051] The solid powder fed by rapid feeding has a gas velocity of 5-25 m / s in the pyrolysis section of the riser. During the upward process of the solid powder, hydrogenation pyrolysis is completed to generate coke powder, tar and crude coal gas. The crude coke powder separated from the crude coal gas at the outlet of the pyrolysis upward zone falls into the heat carrier downward zone and returns to the fluidized bed gasification section through the transition connection section to realize the internal circulation of coke powder.

[0052] The separated crude gas enters the coarse particle separator and fine particle separator sequentially through the outlet of the pyrolysis section of the riser. At the same time, the coarse coke powder and fine coke powder in the crude gas are further separated by the coarse particle separator and fine particle separator, and then enter the set return material lock control structure I, return material lock control structure II and enhanced nozzle I and enhanced nozzle II respectively. The return material mixer I and return material mixer II increase the return material speed to 3-15m / s, forcibly returning the coarse coke powder and fine coke powder to the gasification section. The high-temperature gas formed by gasification rises and enters the pyrolysis section through the transition connection section to realize the external circulation of coke powder.

[0053] After the solid powder circulation is established, the temperature of the pyrolysis section is increased to 450-750℃, the temperature of the gasification section is increased to 450-1150℃, and the temperatures of the coarse particle separator and the fine particle separator are increased to >400℃ respectively.

[0054] Step 4: System shutdown:

[0055] Stop the solid powder feeding system, close the pressurized lock chamber, and after the solid powder is completely conveyed, close the spiral solid powder feeding device while keeping the feed accelerator running continuously. Gradually reduce the gas velocity in the gasification section to the minimum gas velocity that can ensure stable fluidization of the system. Close the return material lock control structure and keep the enhanced nozzle I and enhanced nozzle II running continuously. When the temperature of the pyrolysis-gasification reactor drops below 300℃, close the feed accelerator and enhanced nozzle I and enhanced nozzle II. When the temperature of the pyrolysis-gasification reactor drops below 100℃, further reduce the fluidization gas velocity in the gasification section until it is completely shut down. After completion, the system is shut down.

[0056] Before starting the coupling device, solid powder is pre-filled through the starting feed port. The solid powder is one or more of the following: river sand, power plant fly ash, gasification ash, quartz sand, and mixed waste catalyst, etc., within a certain particle size range.

[0057] By implementing the coupling device and method, the tar yield of one or more mixtures of coal, biomass, and waste plastic particles can be increased to more than 150% of the Geiger tar yield.

[0058] The beneficial effects of this invention are:

[0059] This invention differs from traditional pyrolysis devices by coupling riser pyrolysis and fluidized bed gasification within a pyrolysis-gasification reactor. This enables feedstock feeding and efficient pyrolysis and gasification under a wide range of particle size conditions, solving practical problems in the pyrolysis process such as difficulty in utilizing coke powder, difficulty in separating high-temperature gas and solids, and difficulty in recycling and returning coke powder. It is an effective and efficient coal fractionation technology with the following significant technical advantages:

[0060] (1) The pyrolysis section and the fluidized bed gasification section of the riser of the pyrolysis-gasification reactor are coupled and connected by a transition connection section, realizing the precise control of "two temperature fields and two fluidization fields", and realizing the efficient pyrolysis and gasification conversion of carbon-containing raw materials such as coal powder and biomass.

[0061] (2) The internal circulation of coke powder is established through the heat carrier downward zone of the pyrolysis section, and the forced external circulation of coke powder is established through the coarse particle separation system and the fine particle separation system, which further improves the gasification efficiency and carbon conversion rate. The generated hydrogen-rich gas is further improved by rapid hydrogenation. Through the implementation of the coupling device and method, the tar yield of coal, biomass or a mixture of the two can be increased to more than 150% of the tar yield of Geggen.

[0062] (3) The combination of the spiral solid feeder and the feed accelerator in the solid feed system avoids the problems of low spiral feed pressure and low feed rate, expands the feed particle size range, improves feed efficiency, and reduces mechanical failure rate; the coarse particle separation system and the fine particle separation system establish a forced external circulation of coke powder, which effectively ensures sufficient solid powder material in the gasification section of the coupling device. Attached Figure Description

[0063] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0064] Figure 2 This is a top view showing the arrangement of the pyrolysis-gasification reactor, coarse particle separator, and fine particle separator.

[0065] Figure 3 A schematic diagram of the rectangular opening in the upward pyrolysis zone of the riser section.

[0066] 1 Raw material silo; 2 Pressurized lock silo; 3 Spiral solidification feeder; 4 Feed accelerator; 5 Pyrolysis-gasification reactor; 6 Riser pyrolysis section; 6-1 Pyrolysis ascending zone; 6-2 Heat carrier descending zone; 7 Transition connecting section; 8 Fluidized bed gasification section; 9 Coarse particle separator; 10 Return material lock control structure I; 11 Return material mixer I; 12 Enhanced nozzle I; 13 Fine particle separator; 14 Return material lock control structure II; 15 Return material mixer II; 16 Enhanced nozzle II; 17 Air distribution plate; 17-1 Distributor; 17-2 Ash discharge port. Detailed Implementation

[0067] The present invention will now be described in further detail with reference to the accompanying drawings.

[0068] like Figures 1-3 As shown, a device for riser pyrolysis coupled fluidized bed gasification includes a solid powder feeding system, a pyrolysis-gasification reactor 5, a coarse particle separation system, and a fine particle separation system.

[0069] The solid powder feeding system is used for feeding raw materials under a wide range of particle size conditions;

[0070] The pyrolysis-gasification reactor 5 is used for the pyrolysis and gasification of the raw materials;

[0071] The coarse particle separation system is used to capture coarse particles in the mixed coal gas generated by the pyrolysis-gasification reactor 5.

[0072] The fine particle separation system is used to capture fine particles in the mixed coal gas generated by the pyrolysis-gasification reactor 5.

[0073] The solid feed system can broaden the range of pulverized coal feed particle size, transporting pulverized coal with a wide range of particle size conditions to the pyrolysis-gasification reactor 5. The pyrolysis-gasification reactor 5, through equipment coupling, realizes two reactions in one reactor: pulverized coal pyrolysis and semi-coke gasification. The raw material is directly converted into crude coal gas containing solid semi-coke and coal tar. The crude coal gas enters the coarse particle separation system and the fine particle separation system in sequence to achieve efficient separation of solid particles in stages. It is then returned to the gasification section of the pyrolysis-gasification reactor 5 for gasification reaction through forced return measures.

[0074] The solid powder feeding system consists of, from top to bottom, a raw material silo 1, a pressure lock silo 2, a spiral solid powder feeding device 3, and a feeding accelerator 4.

[0075] The bottom output of the raw material silo 1 is divided into two paths, which are respectively connected to the top input of the pressure lock silo 2. The bottom output of the pressure lock silo 2 is connected to the input of the spiral solidification feed device 3, and the output of the spiral solidification feed device 3 is connected to the input of the feed accelerator 4.

[0076] The pyrolysis-gasification reactor 5 includes a riser pyrolysis section 6, a transition connection section 7, and a fluidized bed gasification section 8.

[0077] The input ends of the riser pyrolysis section 6 and the fluidized bed gasification section 8 are connected to the output end of the feed accelerator 4;

[0078] The riser pyrolysis section 6 and the fluidized bed gasification section 8 are coupled together via a transition connection section 7.

[0079] The riser pyrolysis section 6, transition connection section 7, and fluidized bed gasification section 8 have the same outer diameter. Multiple risers are evenly distributed inside the riser pyrolysis section 6, isolating it into an upward pyrolysis zone 6-1 and a downward heat carrier zone 6-2. The transition connection section 7 is equipped with upward and downward channels. The gasified coal gas from the fluidized bed gasification section 8, carrying solid particles, enters the upward pyrolysis zone 6-1 through the upward channel, mixing and exchanging heat with the feed in the upward pyrolysis zone 6-1 to achieve rapid pyrolysis. The downward heat carrier zone 6-2 achieves preliminary separation of solid particles from the pyrolysis zone. The separated solid particles are returned to the fluidized bed gasification section 8 through the downward channel of the transition connection section 7, achieving gasification of the returned solid particles. This setup achieves temperature zoning for the pyrolysis and gasification processes in the pyrolysis-gasification reactor 5, and couples the pyrolysis of the raw material with the gasification of the semi-coke solid particles.

[0080] The coarse particle separation system includes a coarse particle separator 9, a return material locking structure I10, a return material mixer I11, and a reinforced nozzle I12 arranged sequentially from top to bottom.

[0081] The input end of the coarse particle separator 9 is connected to the output end of the pyrolysis-gasification reactor 5, the input end of the return material lock control structure I10 is connected to the solid output end of the coarse particle separator 9, the input end of the return material mixer I11 is connected to the output end of the return material lock control structure I10, and the input end of the enhanced nozzle I12 is connected to the output end of the return material mixer I11.

[0082] The coarse particle separator 9 adopts a single-tube cyclone separation structure or a multi-tube cyclone separation structure or a series combination, and is designed and matched mainly according to the feed particle size and the particle size of the solid particles at the output end of the pyrolysis-gasification reactor 5.

[0083] The return material locking structure I10 has a locking function to realize the buffering, pressurization, metering and conveying of coarse particles captured by the coarse particle separator 9;

[0084] The return material mixer I11 has a rapid feeding function to improve the feeding rate, enabling rapid conveying of coarse particles output from the return material locking structure I10;

[0085] The fine particle separation system includes, from top to bottom, a fine particle separator 13, a return material locking structure II 14, a return material mixer II 15, and a reinforced nozzle II 16;

[0086] The input end of the fine particle separator 13 is connected to the gas output end of the coarse particle separator 9, the input end of the return material locking structure II 14 is connected to the solid output end of the fine particle separator 13, the input end of the return material mixer II 15 is connected to the output end of the return material locking structure II 14, and the input end of the enhanced nozzle II 16 is connected to the output end of the return material mixer II 15.

[0087] The fine particle separator 13 adopts one or more of the following series combinations: multi-tube cyclone separation structure, metal sintered filter element structure, ceramic sintered filter element structure, or bag filter dust removal filter element structure. It is designed and matched mainly according to the solid particle size at the gas output end of the coarse particle separator 9, the system operating pressure, and the requirements of the downstream process for the solid content in the tar.

[0088] The return material locking structure II14 has a locking function, which realizes the buffering, pressurization, metering and conveying of fine particles captured by the fine particle separator 13;

[0089] The return material mixer II15 has a rapid feeding function to improve the feeding rate, enabling rapid conveying of fine particles output from the return material locking structure II14;

[0090] The riser pyrolysis section 6 includes a pyrolysis upward zone 6-1 and a heat carrier downward zone 6-2;

[0091] Multiple risers are evenly distributed inside the riser pyrolysis section 6, which isolates the riser pyrolysis section 6 into a pyrolysis upward zone 6-1 and a heat carrier downward zone 6-2; the pyrolysis upward zone 6-1 realizes the rapid pyrolysis reaction of the feed, and the heat carrier downward zone 6-2 realizes the preliminary separation of solid particles in the pyrolysis section;

[0092] The spiral solid powder feeding device 3 is connected to the solid powder inlet of the pyrolysis upward zone 6-1 of the riser section via a feeding accelerator 4.

[0093] The riser pyrolysis section 6 is provided with 1 to 6 pyrolysis ascending zones 6-1. The pyrolysis ascending zones 6-1 realize the rapid pyrolysis reaction of the feed. Each pyrolysis ascending zone is provided with an independent solid powder feeding system.

[0094] The top of the riser pyrolysis section 6 is provided with a start-up feed port and a gas outlet. The gas outlet of the riser pyrolysis section 6 is connected to the gas inlet of the coarse particle separator 9 through a straight pipe section, and the gas outlet of the coarse particle separator 9 is connected to the gas inlet of the fine particle separator 13 through a straight pipe section.

[0095] The fluidized bed gasification section 8 is symmetrically equipped with four forced return ports I to IV. The enhanced nozzle I 12 is connected to the forced return port I, the enhanced nozzle II 16 is connected to the forced return port II, and the forced return ports III and IV are spare ports.

[0096] Forced return ports I to IV are located in the middle of fluidized bed gasification section 8, and are evenly distributed.

[0097] The internal components of the coarse particle separator 9 and the fine particle separator 13 adopt one or more of the following combinations: single-tube cyclone separation structure, multi-tube cyclone separation structure, metal sintered filter element structure, ceramic sintered filter element structure, or bag filter element structure.

[0098] The coarse particle separator 9 adopts a single-tube cyclone separation structure or a multi-tube cyclone separation structure or a series combination, and is designed and matched mainly according to the feed particle size and the particle size of the solid particles at the output end of the pyrolysis-gasification reactor 5.

[0099] The fine particle separator 13 adopts one or more of the following series combinations: multi-tube cyclone separation structure, metal sintered filter element structure, ceramic sintered filter element structure, or bag filter dust removal filter element structure. It is designed and matched mainly according to the solid particle size at the gas output end of the coarse particle separator 9, the system operating pressure, and the requirements of the downstream process for the solid content in the tar.

[0100] The top view of the arrangement of the pyrolysis-gasification reactor 5, the coarse particle separator 9 and the fine particle separator 13 is a right-angled triangle structure, and the included angle β of the pyrolysis-gasification reactor 5 and the coarse particle separator 9 ranges from 15° to 90°.

[0101] The gas outlet of the pyrolysis upward zone 6-1 of the riser pyrolysis section is a rectangular opening. The size ratio of the rectangular opening is L length: W width = 1:1 to 2:1, L length: H height = 1:1 to 1:4, and the angle α between the rectangular opening and the horizontal direction is 0 to 60°.

[0102] The bottom of the transition section 7 of the pyrolysis-gasification reactor is provided with 4 to 24 symmetrical natural return ports.

[0103] The bottom of the fluidized bed gasification section 8 of the pyrolysis-gasification reactor is provided with an air distribution plate 17, and the number of distributors 17-1 on the air distribution plate 17 is 10 to 300. Two ash discharge ports 17-2 are horizontally and symmetrically arranged on the air distribution plate 17.

[0104] The solid powder particle size range of the spiral solid powder feeding system is 0.025mm to 20mm, and the feeding speed of the feeding accelerator 4 is 3 to 15m / s.

[0105] The gas velocity in the fluidized bed gasification section 8 is 0.8–5.5 m / s, and the gas velocity in the fluidized bed pyrolysis section 6 is 5–25 m / s.

[0106] The average gas velocity at the gas inlet of the coarse particle separator 9 is 20-35 m / s, and the average gas velocity at the gas inlet of the fine particle separator 13 is 10-25 m / s.

[0107] The solid feed rate of the return material mixer I11 and return material mixer II15 is 3-15 m / s.

[0108] The operating temperature of the riser pyrolysis section 6 is 450–750°C, the operating temperature of the fluidized bed gasification section 8 is 450–1150°C, the operating temperature of the coarse particle separator 9 and the fine particle separator 13 is >300°C, and the operating pressure of the coupling device is 0.1–5.0 MPa.

[0109] The method for riser-coupled pyrolysis fluidized bed gasification includes the following implementation steps:

[0110] Step 1: System Hot Standby

[0111] The temperature of the riser pyrolysis section 6 and fluidized bed gasification section 8 of the pyrolysis-gasification reactor is increased to >300℃ by high-temperature flue gas baking, and the temperature of the coarse particle separator 9 and fine particle separator 13 is increased to above 300℃.

[0112] Step 2: Start the solid powder feeding system:

[0113] The raw material silo 1 and the pressurized lock silo 2 continuously convey solid powder with a particle size range of 0.025mm to 20mm to the spiral solid powder feeding device 3. The feeding accelerator 4 adjusts the feeding air velocity to 3 to 15m / s to quickly convey the solid powder to the pyrolysis section 6 of the riser pipe.

[0114] Step 3: Establish a loop:

[0115] The gas velocity of the rapidly fed solid powder in the riser pyrolysis section is 5-25 m / s. During the upward process of the solid powder, hydrogenation pyrolysis is completed to generate coke powder, tar and crude coal gas. The crude coal gas is separated from the coke powder at the outlet of the pyrolysis upward zone and falls into the heat carrier downward zone. It returns to the fluidized bed gasification section 8 through the transition connection section 7 to realize the internal circulation of coke powder.

[0116] The separated crude gas enters the coarse particle separator 9 and the fine particle separator 13 sequentially after passing through the outlet of the pyrolysis section. At the same time, the coarse coke powder and fine coke powder in the crude gas are further separated by the coarse particle separator 9 and the fine particle separator 13, and enter the set return material locking structures I, II 10, 14 and enhanced nozzles I, II 12, 16 respectively. The return material mixers I, II 11, 15 increase the return material speed to 3-15 m / s, forcibly returning the coarse coke powder and fine coke powder to the gasification section 8. The high-temperature gas formed by gasification rises and enters the pyrolysis section through the transition connection section to realize the external circulation of coke powder.

[0117] After the solid powder circulation is established, the temperature of the pyrolysis section is increased to 450-750℃, the temperature of the gasification section is increased to 450-1150℃, and the temperatures of the coarse particle separator 9 and the fine particle separator 13 are increased to >400℃ respectively.

[0118] Step 4: System shutdown:

[0119] Stop the solid powder feeding system, close the pressure lock chamber 2, and after the solid powder is completely conveyed, close the spiral solid powder feeding device 3, while keeping the feed accelerator 4 running continuously; gradually reduce the gas velocity in the gasification section 8 to the minimum gas velocity that can ensure stable fluidization of the system; close the return material lock control structure, while keeping the enhanced nozzles I, II, 12, and 16 running continuously; once the temperature of the pyrolysis-gasification reactor 5 drops below 300℃, close the feed accelerator 4 and the enhanced nozzles I, II, 12, and 16; once the temperature of the pyrolysis-gasification reactor 5 drops below 100℃, further reduce the fluidization gas velocity in the gasification section until it is completely shut down, and then stop the system.

[0120] Before startup, the coupling device is pre-filled with solid powder through the start-up feed port. The solid powder is one or more combinations of river sand, power plant fly ash, gasification ash, quartz sand, and mixed spent catalysts within a certain particle size range. The main purposes are twofold: first, to establish the bed level during initial startup, using the heat storage of the solid powder and continuous heat transfer through circulation within the system to raise the temperature of the pyrolysis-gasification reactor 5 to the feed temperature condition; second, during normal startup, the solid powder circulates within the system as an inert medium, reducing the contact between the pyrolysis semi-coke and pyrolysis free radicals and the occurrence of side reactions.

[0121] By implementing the coupling device and method, the tar yield of a mixture of one or more of coal, biomass, and waste plastic particles can be increased to over 150% of the Geiger tar yield. The main reason is that this invention, through a device that couples riser pyrolysis and fluidized bed gasification, achieves both pulverized coal pyrolysis and semi-coke gasification within a single reactor. This enables rapid pulverized coal pyrolysis and hydropyrolysis, reduces the condensation reaction between pyrolysis free radicals, and further improves the tar yield.

[0122] In this invention, the riser pyrolysis section and fluidized bed gasification section of the pyrolysis-gasification reactor are coupled together via a transition section. The riser pyrolysis section includes an upward pyrolysis zone and a downward heat carrier zone. Both the coarse particle separation system and the fine particle separation system are equipped with independent return material locking structures and enhanced nozzles, forcibly returning the collected coarse and fine coke powders to the fluidized bed gasification section, respectively. This invention differs from traditional pyrolysis devices by widening the feed particle size range through a solid powder feeding system. The coupled connection of the pyrolysis-gasification reactor achieves precise control of "two temperature fields and two fluidization fields." Internal circulation and forced external circulation of coke powder improve carbon conversion rate, and the generated hydrogen-rich gas further enhances the pyrolysis tar yield through rapid hydrogenation. This invention solves the practical problems of difficult coke powder utilization, difficult high-temperature gas-solid separation, and difficult coke powder recycling in the pyrolysis process, and is an effective and efficient coal fractionation technology.

[0123] This invention enables the pyrolysis-gasification conversion of carbon-containing raw materials such as low-rank coal and biomass. It improves gasification efficiency and carbon conversion rate through a combination of multiple technologies, and further increases tar yield through rapid hydrogenation pyrolysis. It is an effective and efficient coal fractionation technology.

Claims

1. A device for riser pyrolysis coupled fluidized bed gasification, characterized in that, It includes a solid powder feeding system, a pyrolysis-gasification reactor (5), a coarse particle separation system, and a fine particle separation system; The solid powder feeding system is used for feeding raw materials under a wide range of particle size conditions, expanding the range of particle size of pulverized coal feed, and transporting pulverized coal under a wide range of particle size conditions to the pyrolysis-gasification reactor (5). The pyrolysis-gasification reactor (5) is used to pyrolyze and gasify the raw materials. The pyrolysis-gasification reactor (5) realizes two reactions, pyrolysis of pulverized coal and gasification of semi-coke, through equipment coupling. The raw materials are directly converted into crude coal gas containing solid semi-coke and coal tar. The crude coal gas enters the coarse particle separation system and the fine particle separation system in sequence to realize the efficient separation of solid particles step by step. The coarse particle separation system is used to capture coarse particles in the mixed gas generated by the pyrolysis-gasification reactor (5); The fine particle separation system is used to capture fine particles in the mixed coal gas generated by the pyrolysis-gasification reactor (5); The coarse particle separation system and the fine particle separation system are returned to the gasification section of the pyrolysis-gasification reactor (5) for gasification reaction through forced return measures.

2. The apparatus for riser-coupled fluidized bed gasification according to claim 1, characterized in that, The solid powder feeding system consists of, from top to bottom, a raw material silo (1), a pressure lock silo (2), a spiral solid powder feeding device (3), and a feeding accelerator (4); The bottom output of the raw material silo (1) is divided into two paths, which are respectively connected to the top input of the pressure lock silo (2). The bottom output of the pressure lock silo (2) is connected to the input of the spiral solid powder feeding device (3), and the output of the spiral solid powder feeding device (3) is connected to the input of the feeding accelerator (4).

3. The apparatus for riser-coupled fluidized bed gasification according to claim 2, characterized in that, The pyrolysis-gasification reactor (5) includes a riser pyrolysis section (6), a transition connection section (7), and a fluidized bed gasification section (8). The input ends of the riser pyrolysis section (6) and the fluidized bed gasification section (8) are connected to the output end of the feed accelerator (4). The riser pyrolysis section (6) and the fluidized bed gasification section (8) are coupled together through a transition connection section (7). Multiple risers are evenly distributed inside the riser pyrolysis section (6), which isolates the riser pyrolysis section (6) into a pyrolysis upward zone (6-1) and a heat carrier downward zone (6-2). The transition connection section (7) is provided with an upward channel and a downward channel. The gasified coal gas of the fluidized bed gasification section (8) carries solid particles through the upward channel into the pyrolysis upward zone (6-1), mixes and exchanges heat with the feed of the pyrolysis upward zone (6-1), and realizes the rapid pyrolysis reaction of the feed. The heat carrier downward zone (6-2) realizes the preliminary separation of solid particles in the pyrolysis section. The separated solid particles are returned to the fluidized bed gasification section (8) through the downward channel of the transition connection section (7) to realize the gasification of the returned solid particles.

4. The apparatus for riser pyrolysis coupled fluidized bed gasification according to claim 3, characterized in that, The spiral solid powder feeding device (3) is connected to the solid powder inlet of the pyrolysis upward zone (6-1) of the riser section through a feeding accelerator (4); The riser pyrolysis section (6) is equipped with 1 to 6 pyrolysis ascending zones (6-1). The pyrolysis ascending zones (6-1) realize the rapid pyrolysis reaction of the feed. Each pyrolysis ascending zone is equipped with an independent solid powder feeding system. The top of the riser pyrolysis section (6) is provided with a start-up feed port and a gas outlet. The gas outlet of the riser pyrolysis section (6) is connected to the gas inlet of the coarse particle separator (9) through a straight pipe section. The gas outlet of the coarse particle separator (9) is connected to the gas inlet of the fine particle separator (13) through a straight pipe section.

5. The apparatus for riser pyrolysis coupled fluidized bed gasification according to claim 4, characterized in that, The coarse particle separation system includes a coarse particle separator (9), a return material locking structure I (10), a return material mixer I (11), and a reinforced nozzle I (12) arranged sequentially from top to bottom. The input end of the coarse particle separator (9) is connected to the output end of the pyrolysis-gasification reactor (5), the input end of the return material lock control structure I (10) is connected to the solid output end of the coarse particle separator (9), the input end of the return material mixer I (11) is connected to the output end of the return material lock control structure I (10), and the input end of the enhanced nozzle I (12) is connected to the output end of the return material mixer I (11). The coarse particle separator (9) adopts a single-tube cyclone separation structure or a multi-tube cyclone separation structure or a series combination, and is designed and matched according to the feed particle size and the particle size of the solid particles at the output end of the pyrolysis-gasification reactor (5). The return material locking structure I (10) realizes the buffering, pressurization, metering and conveying of coarse particles captured by the coarse particle separator (9); The return material mixer I (11) enables rapid conveying of coarse particles output from the return material locking structure I (10).

6. The apparatus for riser pyrolysis coupled fluidized bed gasification according to claim 5, characterized in that, The fine particle separation system includes, from top to bottom, a fine particle separator (13), a return material locking structure II (14), a return material mixer II (15), and a reinforced nozzle II (16); The input end of the fine particle separator (13) is connected to the gas output end of the coarse particle separator (9), the input end of the return material lock control structure II (14) is connected to the solid output end of the fine particle separator (13), the input end of the return material mixer II (15) is connected to the output end of the return material lock control structure II (14), and the input end of the enhanced nozzle II (16) is connected to the output end of the return material mixer II (15). The fine particle separator (13) adopts one or more of the following combined in series: multi-tube cyclone separation structure, metal sintered filter element structure, ceramic sintered filter element structure or bag filter element structure. The return material locking structure II (14) realizes the buffering, pressurization, metering and conveying of fine particles captured by the fine particle separator (13); The return material mixer II (15) enables rapid conveying of fine particles output from the return material locking structure II (14).

7. The apparatus for riser pyrolysis coupled fluidized bed gasification according to claim 6, characterized in that, The fluidized bed gasification section (8) is symmetrically provided with four forced return ports I to IV. The enhanced nozzle I (12) is connected to the forced return port I, the enhanced nozzle II (16) is connected to the forced return port II, and the forced return ports III and IV are spare ports. Forced return ports I to IV are located in the middle of the fluidized bed gasification section (8) and are evenly distributed. The internal components of the coarse particle separator (9) and fine particle separator (13) adopt one or more combinations of single-tube cyclone separation structure, multi-tube cyclone separation structure, metal sintered filter element structure, ceramic sintered filter element structure or bag dust collector filter element structure. The coarse particle separator (9) adopts a single-tube cyclone separation structure or a multi-tube cyclone separation structure or a series combination thereof; The fine particle separator (13) adopts one or more of the following combined in series: multi-tube cyclone separation structure, metal sintered filter element structure, ceramic sintered filter element structure or bag filter element structure.

8. The apparatus for riser-coupled fluidized bed gasification according to claim 7, characterized in that, The pyrolysis-gasification reactor (5), coarse particle separator (9) and fine particle separator (13) are arranged in a right-angled triangular structure, and the included angle β between the pyrolysis-gasification reactor (5) and coarse particle separator (9) ranges from 15° to 90°. The gas outlet of the pyrolysis upward zone (6-1) of the riser pyrolysis section is a rectangular opening with a size ratio of L (length):W (width) = 1:1 to 2:1, L (length):H (height) = 1:1 to 1:4, and the angle α between the rectangular opening and the horizontal direction is 0 to 60°. The bottom of the transition section (7) of the pyrolysis-gasification reactor is provided with 4 to 24 symmetrical natural return ports; The bottom of the fluidized bed gasification section (8) of the pyrolysis-gasification reactor is provided with an air distribution plate (17), and the number of distributors (17-1) on the air distribution plate (17) is 10 to 300. Two ash discharge ports (17-2) are horizontally symmetrically arranged on the air distribution plate (17).

9. The apparatus for riser pyrolysis coupled fluidized bed gasification according to claim 8, characterized in that, The solid powder particle size range of the spiral solid powder feeding device (3) is 0.025mm to 20mm, and the feeding speed of the feeding accelerator (4) is 3 to 15m / s; The gas velocity in the fluidized bed gasification section (8) is 0.8 to 5.5 m / s, and the gas velocity in the fluidized bed pyrolysis section (6) is 5 to 25 m / s. The average gas velocity at the gas inlet of the coarse particle separator (9) is 20-35 m / s, and the average gas velocity at the gas inlet of the fine particle separator (13) is 10-25 m / s. The solid feed rate of the return mixer I (11) and the return mixer II (15) is 3 to 15 m / s; The operating temperature of the riser pyrolysis section (6) is 450-750℃, the operating temperature of the fluidized bed gasification section (8) is 450-1150℃, the operating temperature of the coarse particle separator (9) and the fine particle separator (13) is >300℃, and the operating pressure of the coupling device is 0.1-5.0MPa.

10. The method for riser-coupled fluidized bed gasification using the apparatus according to any one of claims 1-9, characterized in that, The implementation steps include the following: Step 1: System Hot Standby The temperature of the riser pyrolysis section (6) and fluidized bed gasification section (8) of the pyrolysis-gasification reactor is increased to >300℃ by high temperature flue gas baking, and the temperature of the coarse particle separator (9) and fine particle separator (13) is increased to above 300℃. Step 2: Start the solid powder feeding system: The raw material silo (1) and the pressurized lock silo (2) continuously transport solid powder with a particle size range of 0.025mm to 20mm to the spiral solid powder feeding device (3). The feeding accelerator (4) adjusts the feeding air velocity to 3 to 15m / s and quickly transports the solid powder to the pyrolysis section (6) of the riser pipe. Step 3: Establish a loop: The solid powder fed by rapid feeding has a gas velocity of 5-25 m / s in the pyrolysis section (6) of the riser. The solid powder completes hydrogenation pyrolysis during the upward process, generating coke powder, tar and crude coal gas. The crude coal gas is separated from the coke powder at the outlet of the pyrolysis upward zone (6-1) and falls into the heat carrier downward zone (6-2). It returns to the fluidized bed gasification section (8) through the transition connection section (7) to realize the internal circulation of coke powder. The separated crude gas enters the coarse particle separator (9) and fine particle separator (13) sequentially through the outlet of the pyrolysis section (6) of the riser pipe. At the same time, the coarse coke powder and fine coke powder in the crude gas are further separated by the coarse particle separator (9) and fine particle separator (13) and enter the set return material lock control structure I (10), return material lock control structure II (14) and enhanced nozzle I (12) and enhanced nozzle II (16) respectively. The return material mixer I (11) and return material mixer II (15) increase the return speed to 3-15 m / s, and force the coarse coke powder and fine coke powder to return to the gasification section (8). The high temperature gas formed by gasification rises and enters the pyrolysis section through the transition connection section to realize the external circulation of coke powder. After the solid powder circulation is established, the temperature of the pyrolysis section is increased to 450-750℃, the temperature of the gasification section is increased to 450-1150℃, and the temperature of the coarse particle separator (9) and the fine particle separator (13) is increased to >400℃ respectively. Step 4: System shutdown: Stop the solid powder feeding system, close the pressure lock chamber (2), and after the solid powder is completely conveyed, close the spiral solid powder feeding device (3) and keep the feed accelerator (4) running continuously; gradually reduce the gas velocity of the gasification section (8) to the minimum gas velocity that can ensure stable fluidization of the system; close the return material lock control structure and keep the enhanced nozzle I (12) and enhanced nozzle II (16) running continuously; when the temperature of the pyrolysis-gasification reactor (5) drops below 300℃, close the feed accelerator (4) and enhanced nozzle I (12) and enhanced nozzle II (16); when the temperature of the pyrolysis-gasification reactor (5) drops below 100℃, further reduce the fluidization gas velocity of the gasification section until it is completely closed, and then stop the system.

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