System and method for biomass pyrolysis gasification and energy recycling

Abstract

The application provides a biomass pyrolysis gasification and energy recycling system and method, and belongs to the technical field of biomass gasification. The system comprises a pyrolysis furnace which is suitable for biomass pyrolysis to generate pyrolysis gas and pyrolysis semi-coke; a reforming reactor which is located downstream of the pyrolysis furnace and is suitable for the reaction of a first gasification agent, captured unreacted solid phase materials and pyrolysis gas in the reforming reactor to form crude synthesis gas and ash; and a gasification furnace chamber of a gasification furnace which is connected with a nozzle of the reforming reactor, pyrolysis semi-coke and bed material fed into the gasification furnace chamber are fluidized by a second gasification agent to form fluidized solid materials, the fluidized solid materials are in contact with the crude synthesis gas and ash sprayed into the gasification furnace chamber, the sensible heat of the crude synthesis gas and ash is used to provide heat for the gasification reaction of the pyrolysis semi-coke, and gas-solid materials and gasification liquid slag are generated, and the temperature of the ash is reduced.

Description

Technical Field

[0001] This application belongs to the field of biomass gasification technology, and in particular relates to a system and method for biomass pyrolysis gasification and energy recycling. Background Technology

[0002] Existing fluidized bed gasification technologies generally suffer from high tar content during biomass gasification, leading to easy pipe blockage and making them unsuitable as feedstock for downstream syngas. While high-temperature non-catalytic reforming reactors can convert tar in syngas and methane into carbon monoxide (CO), hydrogen (H2), and carbon dioxide (CO2), the conversion temperature is high (generally requiring heating to 1250℃) and consumes some syngas. Furthermore, the conversion of chemical energy into heat requires even more oxygen; and the high-temperature syngas ultimately generates steam through boiler waste heat recovery, contributing nothing to the gasification reaction and increasing the cost and oxygen consumption of fluidized bed gasification. Summary of the Invention

[0003] To address the aforementioned technical problems, this application provides a system and method for biomass pyrolysis gasification and energy recycling, aiming to at least partially solve the above-mentioned technical problems. The technical solution provided by this application is as follows.

[0004] As a first aspect of this application, a system for biomass pyrolysis gasification and energy recycling is provided, comprising: a pyrolysis furnace, a reforming reactor and a reforming burner located on top of the reforming reactor, and a gasifier.

[0005] The pyrolysis furnace is divided into a lower turbulent fluidization section and an upper expansion section. It is equipped with a primary air inlet at the bottom of the turbulent fluidization section and a discharge port for pyrolysis semi-coke. It is also equipped with a biomass feed port at the bottom of the expansion section and a pyrolysis gas exhaust port at the top. The pyrolysis semi-coke and pyrolysis gas are generated by the pyrolysis of biomass.

[0006] The reforming reactor is equipped with a reforming burner at the top, which is connected to the exhaust port. The reforming burner is suitable for organizing the first gasifying agent, the collected unreacted solid material and pyrolysis gas to enter the reforming reactor for reaction, forming crude syngas and ash.

[0007] A gasifier includes a gasification chamber with a feed inlet for feeding pyrolytic semi-coke and a gasifying agent inlet at the bottom for feeding a second gasifying agent. The second gasifying agent fluidizes the solid material fed into the gasifier chamber. The solid material includes bed material and pyrolytic semi-coke as gasification feedstock. The top of the gasifier chamber is connected to a nozzle at the bottom of a reforming reactor so that crude syngas and ash can come into contact with the fluidized solid material under the impetus of the gas. The sensible heat of the crude syngas and ash is used to heat the gasification reaction of the pyrolytic semi-coke, producing gas-solid materials and bottom ash, while reducing the temperature of the ash. The side wall of the gasifier chamber is also provided with a connection port for discharging the gas-solid materials, which include crude syngas and unreacted solid materials, including fly ash and residue.

[0008] In some embodiments, the gasifier further includes: a connecting section, which is inclined upward and connected to a connection port provided in the gasifier chamber; and a conveying section, which is a fluidized chamber with a water-cooled wall structure, consisting of a first vertical section, a frustum section and a second vertical section from bottom to top, wherein the first vertical section is connected to the connecting section, and the horizontal angle α between the frustum section and the first vertical section is 45°-85°.

[0009] In some embodiments, the biomass pyrolysis gasification and energy recycling system further includes a solid material conveying device and a gas-solid separator. The solid material conveying device has a material inlet connected to a discharge port and a material outlet connected to a feed port; the gas-solid separator has a gas-solid inlet connected to the gas-solid outlet of the conveying section, a solid phase outlet for discharging fly ash, and a gas phase outlet for discharging the gaseous material formed by the crude syngas and its entrained residues.

[0010] In some embodiments, the biomass pyrolysis gasification and energy recycling system further includes: a waste heat boiler and a dust collector arranged sequentially downstream of the gas-solid separator; or a dust collector and a waste heat boiler arranged sequentially downstream of the gas-solid separator.

[0011] In some embodiments, the reforming burner includes a central gasifying agent channel, a fly ash channel surrounding the gasifying agent channel, and a peripheral pyrolysis gas channel. This is suitable for organizing the first gasifying agent entering the reforming reactor to preferentially react with the collected unreacted solid material in a gasification reaction. The resulting mixed gas then undergoes a cracking and reforming reaction with the pyrolysis gas to form crude syngas and ash.

[0012] In some implementations, the solid phase outlet of the gas-solid separator is connected to the fly ash channel of the reformer burner.

[0013] In some embodiments, the solid phase outlet of the gas-solid separator is connected to a pyrolysis furnace and / or the solid phase outlet of the gas-solid separator is connected to a gasification furnace.

[0014] In some implementations, the dust collector's outlet is connected to the fly ash channel of the reforming burner.

[0015] As a second aspect of this application, a method for biomass pyrolysis gasification and energy recycling is provided, comprising:

[0016] In the turbulent fluidization section at the bottom of the pyrolysis furnace, some of the semi-coke reacts with the introduced primary air, and the released heat pyrolyzes the biomass to generate pyrolytic semi-coke and volatiles, the volatiles being pyrolysis gas entrained with semi-coke.

[0017] The volatiles enter the expanded section at the top of the pyrolysis furnace and undergo pre-gas-solid separation to obtain pyrolysis gas;

[0018] The pyrolysis gas, the first gasifying agent, and the collected unreacted solid materials enter the reforming reactor under the organization of the reforming burner to react and form crude syngas and ash.

[0019] The crude syngas and ash are propelled into the gasification furnace by the gas, where they come into contact with the fluidized solid material. The sensible heat of the crude syngas and ash is used to heat the gasification reaction of the pyrolytic semi-coke, producing gas-solid materials and gasified liquid slag, while simultaneously reducing the temperature of the ash. The fluidized solid material is formed by the fluidization of the second gasifying agent introduced into the gasification furnace with the bed material and pyrolytic semi-coke fed into the gasification furnace. The gas-solid material includes crude syngas and unreacted solid material, which includes fly ash and residue.

[0020] In some implementations, the pyrolysis semi-coke is fed into the gasification furnace via a solid material conveying device.

[0021] In some embodiments, the method for biomass pyrolysis gasification and energy recycling further includes: gas and solid materials sequentially passing through a connecting section and a conveying section into a gas-solid separator for gas-solid separation to obtain gas phase materials and fly ash, wherein the gas phase materials include crude syngas and its entrained residues.

[0022] In some implementations, secondary air is introduced into the frustum section of the transport section to carry unreacted solid material to the center and simultaneously pulverize the unreacted solid material.

[0023] In some embodiments, the method of biomass pyrolysis gasification and energy recycling further includes: the gaseous material enters the waste heat boiler for waste heat recovery, and then enters the downstream dust collector to capture the residue in the gaseous material and obtain pure syngas; or the gaseous material enters the dust collector to capture the residue in the gaseous material, and the obtained pure syngas enters the downstream waste heat boiler for waste heat recovery.

[0024] In some embodiments, the collected fly ash is used as a gasification feedstock and enters the reforming reactor through the fly ash channel of the reforming burner for gasification reaction; or the collected fly ash and some or all of the residue are used as gasification feedstock and enter the reforming reactor through the fly ash channel of the reforming burner for gasification reaction.

[0025] In some embodiments, the collected fly ash is fed into a pyrolysis furnace as a gasification feedstock. After pre-separation in the pyrolysis furnace, the fine fly ash enters the reforming burner for gasification, while the coarse fly ash enters the gasification furnace via a solid material conveying device for gasification. Alternatively, the collected fly ash is fed into the gasification furnace as a gasification feedstock for continued gasification, while simultaneously serving as a cold feedstock to cool the high-temperature crude syngas and ash residue from the reforming reactor.

[0026] Based on the above technical solution, the system and method for biomass pyrolysis gasification and energy recycling of this application have at least one of the following beneficial effects:

[0027] (1) In this application, biomass pyrolysis and gasification are decoupled by structural design, and tar and biomass (i.e. carbon) are gasified separately. The pyrolysis gas carrying tar is completely converted by cracking and reforming, thus solving the problem of tar and methane from biomass gasification from the source and reducing the problem of high oxygen consumption caused by first gasification and then reforming and gasification of syngas.

[0028] (2) In this application, by utilizing the full fluidization and strong internal circulation of the gasification furnace, the crude syngas and ash entering the gasification reaction zone are quickly dispersed to avoid slagging, and its sensible heat is fully utilized for the gasification reaction of pyrolysis semi-coke. This can solve the slagging problem of biomass gasification and make full use of the sensible heat of gasification, which can significantly improve the thermal efficiency of biomass gasification and reduce oxygen consumption. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the biomass pyrolysis gasification and energy recycling system of this application.

[0030] Figure 2 This is a schematic diagram of the reforming reactor in this application;

[0031] Figure 3 This is a schematic diagram showing the connection between the connecting section and the transport section in this application;

[0032] Figure 4 This is a schematic diagram of the opposing air duct for arranging secondary air in the transport section, as described in this application.

[0033] [Attached image labels]

[0034] 1-Pyrolysis furnace, 11-Primary air inlet, 12-Discharge port, 13-Discharge port, 14-Feeding port, 15-Exhaust port;

[0035] 2-Solid material conveying device, 21-Material inlet, 22-Material outlet;

[0036] 3-Gasifier, 3-1 Gasifier chamber, 3-2-Connecting section, 3-3-Transporting section, 31-Gasifying agent inlet, 32-Slag discharge port, 33-Feed inlet, 34-Gas-solid outlet, 35-Connecting port, 36-Counteracting air duct;

[0037] 4-Reformer reactor, 41-Reformer burner, 42-Nozzle;

[0038] 5-Gas-solid separator, 51-Gas-solid inlet, 52-Solid phase outlet, 53-Gas phase outlet;

[0039] 6- Waste heat boiler, 61- Hot end inlet, 62- Cold end outlet;

[0040] 7-Dust collector, 71-Dust inlet, 72-Product gas outlet, 73-Ash discharge port;

[0041] A - Unreacted solid material, B - Biomass, C - Pyrolysis semi-coke, D - Gas phase material, PYG - Pyrolysis gas, PG - Crude syngas, F - Bottom ash, G - Pure syngas, g1 - Primary air, g3 - First gasifying agent, g2 - Secondary gasifying agent, g4 - Secondary air, A1 - Fly ash, A2 - Residue. Detailed Implementation

[0042] To address the problems of high tar content, high oxygen consumption, and high required gasification temperature in existing fluidized bed biomass gasification processes, this application proposes a novel biomass pyrolysis gasification and energy utilization system and method. Through structural design, the biomass pyrolysis and gasification processes are decoupled, while simultaneously coupling biomass pyrolysis and pyrolysis gas reforming. This solves the problem of high tar and methane content in the syngas produced by biomass gasification and also helps to increase the yield of effective gas. More importantly, the biomass pyrolysis gasification and energy utilization system of this application is particularly suitable for pressurized reactions, effectively avoiding material cross-contamination and / or backflow problems. Through structural design, energy from biomass pyrolysis and gasification is also recovered, improving energy utilization efficiency.

[0043] Figure 1 This is a schematic diagram of the biomass pyrolysis gasification and energy recycling system of this application.

[0044] like Figure 1 As shown, the biomass pyrolysis gasification and energy recycling system includes: a pyrolysis furnace 1, a solid material conveying device 2, a gasification furnace 3, a reforming reactor 4, a gas-solid separator 5, a waste heat boiler 6, and a dust collector 7. The gasification furnace 3 includes a gasification furnace chamber 3-1, a connecting section 3-2, and a conveying section 3-3.

[0045] The pyrolysis furnace 1 is a turbulent fluidized bed, serving as the main reaction zone for producing pyrolysis gas (PYG) and pyrolysis semi-coke (C) from the pyrolysis of biomass B. It is divided into a lower turbulent fluidized section and an upper expansion section. The turbulent fluidized section is a truncated cone-shaped section, wider at the top and narrower at the bottom, with an inclination angle of 45°-80°. The expansion section includes a separation zone. At the bottom of the turbulent fluidized section are an air distribution unit consisting of an air cap, air distribution plate, and air chamber; a primary air inlet 11; and a bottom ash discharge port 12. A pyrolysis semi-coke discharge port 13 is located on the side wall of the turbulent fluidized section. At the bottom of the expansion section is a biomass B feed port 14, and at the top is a pyrolysis gas (PYG) exhaust port 15. Primary air (g1) enters the air distribution unit at the bottom of the pyrolysis furnace 1 through the primary air inlet 11, and then enters the turbulent flow section via the air distribution unit consisting of the air cap, air distribution plate, and air chamber to participate in the pyrolysis of biomass B. The interior of the pyrolysis furnace 1 is divided into a dilute phase zone, a transition zone, and a dense phase zone from top to bottom. The discharge port 13 is located in the dense phase zone of the pyrolysis furnace 1 and is 0.5-2.0m away from the air distribution plate. The feed port 14 of biomass B is located in the dilute phase zone of the pyrolysis furnace 1 and is 2.5-6m away from the air distribution plate. The angle between the feed port 14 and the discharge port 13 is 90°-180°. Inside the pyrolysis furnace 1, part of the semi-coke reacts with the introduced primary air g1 and is heated to form hot semi-coke to meet the heat required for the pyrolysis of biomass B. Biomass B enters the pyrolysis furnace 1 through the feed port 14, mixes with the turbulent hot semi-coke in the furnace of the pyrolysis furnace 1 and is heated, releasing volatiles (i.e., pyrolysis gas PYG) and producing pyrolysis semi-coke C. The pyrolysis gas PYG, carrying some semi-coke (hot semi-coke, pyrolysis semi-coke C), enters the expansion section of pyrolysis furnace 1 for pre-gas-solid separation, capturing the entrained coarse semi-coke. The pre-separated pyrolysis gas PYG is discharged from the exhaust port 15 set at the top of the furnace of pyrolysis furnace 1; or, by setting a cyclone separator inside the expansion section of pyrolysis furnace 1, the coarse semi-coke carried by the pyrolysis gas PYG is captured and returned to the dense phase zone of pyrolysis furnace 1 through the return leg of the cyclone separator.

[0046] The reforming reactor 4 is equipped with a reforming burner 41 at the top, which is connected to the exhaust port 15. The reforming burner 41 is suitable for organizing the first gasifying agent g3, the collected unreacted solid material A and the pyrolysis gas PYG to enter the reforming reactor 4 for reaction, forming crude syngas and ash.

[0047] Figure 2 This is a schematic diagram of the reforming reactor in this application.

[0048] Combination Figures 1-2As shown, the reforming reactor 4 is located downstream of the pyrolysis furnace 1. A reforming burner 41, connected to the exhaust port 15, is installed at its top, and a nozzle 42 is installed at its bottom. The reforming burner 41 is designed according to the principle that the gasifying agent preferentially reacts with the collected unreacted solid material, utilizing the heat generated by the reaction between the gasifying agent and the unreacted solid material to perform cracking and reforming reactions on the pyrolysis gas. Therefore, the reforming burner 41 in this application is a multi-channel burner, including a central gasifying agent channel, a fly ash channel surrounding the gasifying agent channel, and an outer pyrolysis gas channel. The gasifying agent channel serves as the channel for the first gasifying agent g3, the fly ash channel serves as the channel for the unreacted solid material A, and the pyrolysis gas channel serves as the channel for pyrolysis gas PYG. Under the organization of the reformer burner 41, the first gasifying agent g3 entering the reformer reactor 4 preferentially reacts with the collected unreacted solid material A (including fly ash A1 and some or all of the residue A2) to form a gasification reaction. The resulting mixed gas then undergoes cracking and reforming reaction with the pyrolysis gas PYG to form crude syngas (including CO, CO2 and H2) and ash residue.

[0049] The reforming reactor 4 of this application has a height-to-diameter ratio of 2-5 and an average gas phase residence time of 3-8 seconds to ensure complete gasification of unreacted solid materials (fly ash A1 and optional residue A2) and sufficient cracking and reforming of pyrolysis gas PYG, producing high-temperature crude syngas and high-temperature ash residue. The reacted crude syngas and ash residue are ejected through nozzle 42 at the bottom of the reforming reactor 4 and injected into the gasification furnace 3-1 of the gasifier 3.

[0050] In some embodiments, depending on the amount of pyrolysis gas (PYG), a gasifying agent channel can be set around the pyrolysis gas channel to enhance the pyrolysis reaction between the first gasifying agent g3 and the pyrolysis gas (PYG), thereby cracking and reforming the tar, methane, and hydrocarbons in the pyrolysis gas (PYG) into CO, CO2, and H2.

[0051] The gasifier 3 includes a gasifier chamber 3-1. The top of the gasifier chamber 3-1 is connected to the nozzle 42 at the bottom of the reforming reactor 4. The gasifier chamber 3-1 is provided with a feed inlet 33 for feeding pyrolytic semi-coke C, a gasifying agent inlet 31 for feeding the second gasifying agent g2, and a slag discharge outlet 32 ​​for discharging the bottom ash and the mixed slag W composed of the bottom ash from the gasification reaction of pyrolytic semi-coke C and the ash from the reforming reactor 4. A connection outlet 35 for discharging gas-solid materials is also provided on the side wall of the transition zone or dilute phase zone of the gasifier chamber 3-1. Pyrolytic semi-coke C is fed into the gasifier chamber 3-1 as gasification feedstock. The second gasifying agent g2 enters the gasifier chamber 3-1 through the gasifying agent inlet 31 to fluidize the solid materials fed into the gasifier chamber 3-1 using the second gasifying agent g2. The solid materials include bed material and pyrolytic semi-coke C as gasification feedstock. The crude syngas and ash produced by the reforming reactor 4 are injected into the gasification furnace 3-1 through nozzle 42, so that the crude syngas and ash can come into contact with the fluidized solid material under the impetus of the gas. The sensible heat of the crude syngas and ash is used to heat the gasification reaction of the pyrolysis semi-coke C, producing gas-solid materials and bottom ash, while reducing the temperature of the ash. The gas-solid materials include crude syngas PG and unreacted solid material A, which includes fly ash A1 and residue A2.

[0052] In this application, due to the high volatile matter and alkali metal content of biomass B, conventional fluidized bed gasification cannot completely crack the tar, resulting in high contents of tar, methane, C2, and C3 gases in the crude syngas, increasing the cost of crude syngas purification. To address this, this application employs a turbulent fluidized bed (i.e., pyrolysis furnace 1), a gasification furnace 3, and a reforming reactor 4 to decouple the pyrolysis and gasification of biomass B, while simultaneously coupling the pyrolysis of biomass and the reforming of pyrolysis gas PYG. This solves the problem of high tar and methane content in biomass gasification and also increases the effective gas yield. Specifically, through structural design of the pyrolysis furnace 1, biomass B comes into contact with the introduced primary air g1, achieving self-supply of the energy required for cracking through chemical reaction, producing pyrolysis semi-coke C, and simultaneously releasing pyrolysis gas PYG. The pyrolysis gas PYG is discharged through the exhaust port 15 at the top of the pyrolysis furnace 1 and enters the reforming burner 41 located at the top of the reforming reactor 4. By designing the structure of the gasifying agent channel, fly ash channel, and pyrolysis gas channel of the reformer burner 41, the first gasifying agent g3 entering the reformer reactor 4 preferentially reacts with the collected unreacted solid material A to form a gasification reaction. The resulting mixed gas then undergoes cracking and reforming reactions with the pyrolysis gas PYG to form crude syngas PG and ash. The pyrolysis gas PYG is fully cracked and reformed into CO, CO2, and H2, improving the gasification efficiency and effective gas yield of the unreacted solid material A, while reducing the consumption of the first gasifying agent g3. The pyrolysis semi-coke C produced by the pyrolysis of biomass B is fed into the gasification furnace 3-1 of the gasifier, where it mixes with the second gasifying agent g2 and the bed material entering the gasification furnace 3-1 and is fluidized to form fluidized solid material. Through the combined action of the gasification furnace 3-1 structure and the air distribution unit, the pyrolysis semi-coke C is fully fluidized, while the gasification reaction zone at the bottom of the internal circulation gasification furnace 3-1 is strengthened. This rapidly disperses the crude syngas (PG) and ash entering this gasification reaction zone, preventing slagging. Furthermore, driven by the gas, the gas comes into contact with the fluidized solid material, utilizing its sensible heat for the gasification reaction of the pyrolysis semi-coke C. This solves the slagging problem in biomass B gasification and fully utilizes the sensible heat of gasification, significantly improving the thermal efficiency of biomass B gasification and reducing oxygen consumption. Therefore, the pyrolysis furnace 1 of this application is the main site for the pyrolysis of biomass B, the reforming reactor 4 is the main site for the cracking and reforming of pyrolysis gas (PYG) and the gasification of unreacted solid material A, and the gasification furnace 3-1 of the gasification furnace 3 is the site for the recovery of sensible heat from high-temperature crude syngas and high-temperature ash for the gasification of pyrolysis semi-coke C, as well as for ash cooling.

[0053] In some embodiments, the gasifier 3 of this application is a turbulent fluidized bed. The gasification furnace 3-1 of the gasifier 3 consists of a truncated cone section (smaller at the bottom and larger at the top) and a vertical section located above the truncated cone section, wherein the inclination angle of the truncated cone section is 55°-80°. Further, an air distribution device (straight cylinder section) is provided at the bottom of the truncated cone section. This air distribution device consists of an air cap, an air distribution plate, and an air chamber. The second gasifying agent g2 enters the air distribution device through the gasifying agent inlet 31, ensuring that the second gasifying agent g2 is evenly distributed within the gasification furnace 3-1. In terms of material distribution, the internal region of the gasification furnace 3-1 is divided from top to bottom into a dilute phase zone, a transition zone, and a dense phase zone. The feed inlet 33 is located in the dilute phase zone or transition zone of the gasification furnace 3-1 and is 0.5-4m away from the bottom gasifying agent inlet 31, ensuring that the pyrolysis semi-coke C from the solid material conveying device 2 can stably and continuously enter the gasification furnace 3-1. The interface connected to the nozzle 42 at the bottom of the reforming reactor 4 is located at the top of the gasifier 3-1. It receives high-temperature crude syngas (PG) and high-temperature ash from the reforming reactor 4. Utilizing the high heat and mass transfer efficiency of the fluidized bed and the high-ratio internal circulation (circulation ratio exceeding 100) of the bed material and pyrolytic semi-coke (C), the sensible heat of the high-temperature crude syngas (PG) and high-temperature ash is absorbed and used for the gasification reaction of the pyrolytic semi-coke (C). Simultaneously, the high-temperature ash is cooled to 800-850℃ to form solid ash. The mixed ash W, consisting of the bottom ash and solid ash from the gasification reaction of the pyrolytic semi-coke (C), is discharged from the ash discharge port 32 at the bottom of the gasifier 3-1.

[0054] Continue as Figure 1 As shown, the gasifier 3 of this application includes not only the gasifier furnace 3-1 mentioned above, but also a connecting section 3-2 and a conveying section 3-3. The connecting section 3-2 is used to connect the gasifier furnace 3-1 and the conveying section 3-3. The connecting section 3-2 is connected to the connecting port 35 provided on the side wall of the gasifier furnace 3-1. The top of the conveying section 3-3 is provided with a gas-solid outlet 34.

[0055] Figure 3 This is a schematic diagram showing the connection between the connecting section and the transport section of this application.

[0056] Combination Figure 1 and Figure 3As shown, connecting section 3-2 is inclined upwards and connects to the dilute phase zone of gasification furnace 3-1 through connecting port 35 provided on the side wall of gasification furnace 3-1. Connecting port 35 is higher than feed port 33 and the angle between them is 90°-180°. It is 5m-7m away from gasifying agent inlet 31, thus preventing ungasified pyrolysis semi-coke C from entering connecting section 3-2 and escaping from gasification furnace 3-1 under the entrainment of gas. A blind path is provided at the end of connecting section 3-2 away from connecting port 35. The length of the blind path is 0.2-1.25 times the diameter of connecting section 3-2. The horizontal angle at the connection point between connecting section 3-2 and gasification furnace 3-1 is 30-70°. The connection angle β between connecting section 3-2 and transport section 3-3 is 20-60°. The gas-solid materials inside the gasifier furnace 3-1 enter the connecting section 3-2 through the connecting port 35. The aforementioned blind channel provides a buffer zone by redirecting the gas-solid materials (including crude syngas PG and its entrained unreacted solid material A) at a large angle within the connecting section 3-2. This also enhances the mixing and uniform distribution between the gas and solid components, preventing unreacted solid material A from segregating and settling at the bottom of the connecting section 3-2, thus avoiding coking. The horizontal angle between the connecting section 3-2 and the gasifier furnace 3-1 and the conveying section 3-3 is designed to enhance gas-solid mixing uniformity while reducing the entrainment of solid particles by the gas.

[0057] The connection between transport section 3-3 and connecting section 3-2 extends along the gas direction. Transport section 3-3 consists of a first vertical section, a frustum section (smaller at the bottom and larger at the top), and a second vertical section from bottom to top. The diameter of the first vertical section is smaller than the diameter of the second vertical section. The first vertical section is connected to connecting section 3-2. The horizontal angle α between the frustum section and the first vertical section is 45°-85°.

[0058] To address the core issue of alkali metal compound vapors volatilized from biomass B easily contaminating the heat exchange tubes / surfaces of the downstream waste heat boiler 6, thus causing unstable operation of the gasifier 3, this application employs a fluidized bed furnace with water-cooled walls in the transport section 3-3. Utilizing the scouring and strong heat exchange capacity of the fluidized bed furnace, the temperature range for alkali metal compound condensation and contamination is placed within the fluidized bed water-cooled wall transport section 3-3, effectively absorbing the sensible heat of gasification while resolving the alkali metal contamination problem. For atmospheric pressure structures, the water-cooled walls serve as both furnace walls and heat-absorbing surfaces; for pressurized structures, the water-cooled walls only function as heat-absorbing surfaces, with a pressure vessel installed outside the water-cooled walls. To reduce wear on the water-cooled walls from gaseous and solid materials (especially solid particles), a 30mm-80mm thick wear-resistant layer is applied to the water-cooled walls. Furthermore, in order to prevent the alkali metal compounds in biomass B from contaminating, sticking, and corroding the heat exchange tubes / heat exchange surfaces inside the downstream waste heat boiler 6, the temperature at the outlet of the transport section 3-3 is controlled below 400℃.

[0059] Furthermore, this application may also install multiple sets of opposing air ducts for secondary air g4 in the frustum section of transport section 3-3, with the specific structure as follows: Figure 4 As shown.

[0060] Figure 4 This is a schematic diagram of the opposing air duct for arranging secondary air in the transport section, as described in this application.

[0061] like Figure 4 As shown, multiple sets of opposing air ducts 36 are installed in the frustum section of transport section 3-3 to allow secondary air g4 to enter. By controlling the air velocity in connecting section 3-2 and transport section 3-3, the solid material can be concentrated in the frustum section of transport section 3-3. The installation of multiple sets of opposing air ducts 36 in the frustum section of transport section 3-3 facilitates the gasification reaction between unreacted solid material A and secondary air g4, improving the carbon conversion rate. There are at least four opposing air ducts 36, each arranged horizontally in opposition. The ejected secondary air g4 carries the falling unreacted solid material A to the center, causing collision and pulverization, which promotes the formation of fine powder and improves the gasification effect in the subsequent return to the reforming reactor 4.

[0062] Continue as Figure 1 As shown, the biomass pyrolysis gasification and energy recycling system of this application further includes: a solid material conveying device 2, which is equipped with a material inlet 21 connected to the discharge port 13 of the pyrolysis furnace 1 and a material outlet 22 connected to the feed port 33 of the gasifier 3. The solid material conveying device 2 of this application is a non-mechanical conveying device capable of stably conveying pyrolysis semi-coke C to the gasifier 3. It can generally employ U-valve, V-valve, L-valve, or a Venturi conveyor. Furthermore, to ensure the smooth return of pyrolysis semi-coke C, the material inlet 21 needs to maintain a riser height of 0.5-3m.

[0063] Continue as Figure 1 As shown, the biomass pyrolysis gasification and energy recycling system of this application further includes: a gas-solid separator 5, suitable for gas-solid separation of the aforementioned gas-solid material (i.e., unreacted solid material A entrained in the crude syngas PG), capturing fly ash A1 in the unreacted solid material A to obtain gaseous material D, which includes crude syngas PG and selectively entrained residue A2. Therefore, the gas-solid separator 5 of this application is provided with a gas-solid inlet 51 connected to the gas-solid outlet 34 of the conveying section 3-3, a solid outlet 52 for discharging fly ash A1, and a gas outlet 53 for discharging crude syngas PG and its selectively entrained residue A2 to form gaseous material D. The gas-solid separator 5 of this application can be a high-efficiency cyclone separator or other high-efficiency gas-solid separator with a separation efficiency ≥99%.

[0064] In some embodiments, the solid outlet 52 of the gas-solid separator 5 is connected to the pyrolysis furnace 1. Through the pre-separation of the pyrolysis furnace 1, the coarse fly ash A1 enters the gasifier 3 through the solid material conveying device 2, while the fine fly ash A1 is carried by the pyrolysis gas PYG into the reforming burner 41 and then into the reforming reactor 4 for gasification reaction.

[0065] In some embodiments, the solid outlet 52 of the gas-solid separator 5 is connected to the gasifier 3 so that fly ash A1 continues to participate in the gasification reaction in the lower middle part of the gasification furnace 3-1 of the gasifier 3, while increasing the amount of cold material and enhancing the cooling of the high-temperature crude syngas and ash residue from the reformer 4 by the gasifier 3.

[0066] Continue as Figure 1 As shown, the biomass pyrolysis gasification and energy recycling system of this application also includes: a waste heat boiler 6 and a dust collector 7.

[0067] Waste heat boiler 6 is suitable for heat exchange between gaseous material D and the heat exchange medium entering the waste heat boiler 6. Therefore, it is equipped with a hot end inlet 61 for gaseous material D to enter and a cold end outlet 62 for the cooled gaseous material D to exit. The waste heat boiler 6 of this application consists of an evaporator and an economizer. The evaporator is a fire-tube structure or a large-pitch in-line tube bundle structure; the economizer is a large-pitch in-line tube bundle structure. The waste heat boiler 6 of this application shares a steam drum with the water-cooled wall in the transport section 3-3, forming the entire waste heat recovery system.

[0068] The dust collector 7 is used to collect the residue A2 entrained in the crude syngas PG in the gaseous material D to obtain pure syngas G. Therefore, it is equipped with a dust collection inlet 71 for the (cooled) gaseous material D to enter, a product gas outlet 72 for the pure syngas G to exit, and an ash discharge outlet 73 for the residue A2 to exit.

[0069] In some embodiments, the waste heat boiler 6 and the dust collector 7 can be flexibly configured according to actual needs. For example, the waste heat boiler 6 and the dust collector 7 can be sequentially installed downstream of the gas-solid separator 5. The waste heat boiler 6 is used to recover the waste heat of the gaseous material D first, and then the dust collector 7 is used to capture the residue A2 entrained in the crude syngas PG. Alternatively, the positions of the dust collector 7 and the waste heat boiler 6 can be interchanged, that is, the dust collector 7 and the waste heat boiler 6 can be sequentially installed downstream of the gas-solid separator 5. The dust collector 7 is used to capture the residue A2 entrained in the crude syngas PG first, and a large amount of alkali metal compounds are adsorbed on the residue A2 and captured by the dust collector 7 together. Then, the waste heat in the crude syngas PG is recovered. The dust collector 7 in this application can be a metal filter dust collector or a bag filter dust collector. When it is a metal filter dust collector, its operating temperature is 300-450℃.

[0070] In some embodiments, the solid phase outlet 52 of the gas-solid separator 5 is connected to the fly ash channel of the reforming burner 41. The fly ash A1 collected by the gas-solid separator 5 can be returned to the reforming reactor 4 through a return device to continue participating in the gasification reaction. Furthermore, the ash discharge port 73 of the dust collector 7 is connected to the fly ash channel of the reforming burner 41. The fly ash A1 collected by the gas-solid separator 5 can also be mixed with the residue A2 collected by the dust collector 7 and used together as gasification feedstock for the reforming reactor 4 for gasification reaction.

[0071] Existing biomass gasification devices that couple pyrolysis furnaces and gasifiers are generally suitable for atmospheric pressure, but suffer from cross-flow or poor material return under pressure. The biomass pyrolysis gasification and energy recycling system of this application, through the aforementioned structural design, can effectively avoid these problems, especially in pressurized applications. For example, related technologies employ biomass gasification devices that couple pyrolysis furnaces and gasifiers using a dual fluidized bed, where the heat of the pyrolysis furnace comes from the circulating material heated by the gasifier. The pyrolysis furnace and gasifier are two fluidized beds located in the circulating fluidized bed loop. Stable operation of the circulating fluidized bed loop requires that the pressure drop provided by the return device and riser be comparable to the pressure drop of the gasifier and cyclone separator. However, under pressure, as the pressure increases, the pressure drop in the gasifier furnace and cyclone separator increases significantly, and the pressure drop provided by the return device and riser is not easily achieved in a dual fluidized bed structure. Therefore, under pressure, cross-flow and poor material return occur. In this application, the pyrolysis furnace 1 and gasification furnace 3 flow unidirectionally along with the material. Under pressurized conditions, the source pressure provided by the pyrolysis furnace 1 can overcome the problems of increased pressure drop in the cyclone separator and increased pressure drop in the conveying section 3-3 caused by pressurization. Therefore, it is more suitable for pressurized operation.

[0072] As a second aspect of this application, a method for biomass pyrolysis gasification and energy recycling is provided, comprising: in the turbulent fluidization section at the bottom of the pyrolysis furnace 1, a portion of the semi-coke reacts with the introduced primary air g1, and the released heat pyrolyzes the biomass B to generate pyrolysis semi-coke C and volatiles, the volatiles being pyrolysis gas PYG entrained with semi-coke; the volatiles enter the expansion section at the top of the pyrolysis furnace 1 and undergo pre-gas-solid separation to obtain pyrolysis gas PYG; the pyrolysis gas PYG, together with the first gasifying agent g3 and the collected unreacted solid material A, enters the reforming reactor 4 through a reforming burner 41 with a multi-channel structure, and according to the structure of the reforming burner 41, the first gasifying agent g3 entering the reforming reactor 4 preferentially reacts with the unreacted solid material. Material A undergoes a gasification reaction to form a mixed gas, which is then cracked and reformed with pyrolysis gas PYG to form crude syngas PG and ash residue. The crude syngas PG and ash residue are propelled into the gasification furnace 3-1 by the gas, where they come into contact with the fluidized solid material. The sensible heat of the crude syngas PG and ash residue is used to heat the gasification reaction of the pyrolysis semi-coke C, producing gas-solid materials and gasified liquid slag, while simultaneously reducing the temperature of the ash residue. The fluidized solid material is formed by the second gasifying agent g2 introduced into the gasification furnace 3-1 and the bed material and pyrolysis semi-coke C fed into the gasification furnace 3-1. The gas-solid material includes crude syngas PG and unreacted solid material A, which includes fly ash A1 and residue A2.

[0073] In this application, the proposed biomass pyrolysis gasification device and energy recycling system decouple the pyrolysis and gasification reactions of biomass B by using pyrolysis furnace 1 and gasification furnace 3. The tar and pyrolysis semi-coke C in the pyrolysis gas PYG are gasified separately. The pyrolysis gas PYG carrying tar completely converts the tar through a reforming reaction. This solves the problem of tar and methane in biomass B gasification from the source, avoiding the excessive oxygen consumption caused by the traditional route of first gasifying biomass B and then gasifying all the crude syngas and its entrained unreacted solid materials through a non-catalytic reforming reaction, which reduces the economic benefits of biomass B gasification to syngas.

[0074] In some embodiments, pyrolysis furnace 1 is the site where biomass B is pyrolyzed to produce pyrolysis gas PYG and pyrolysis semi-coke C. The pyrolysis temperature in pyrolysis furnace 1 is 700-800℃, and the pyrolysis temperature is controlled by controlling the oxygen content in primary air g1. Primary air g1 is introduced from the bottom of the pyrolysis furnace, and its oxygen concentration is 15%-45%. Primary air g1 can be selected from a mixture of oxygen and water vapor or carbon dioxide, or a mixture of water vapor and carbon dioxide. In the turbulent fluidization section at the bottom of pyrolysis furnace 1, the apparent fluidization velocity is 1.5-3.0 m / s, and the apparent fluidization velocity in the upper expansion section is 0.5-1.0 m / s. The amount of volatile matter removed from biomass B in pyrolysis furnace 1 accounts for 65%-90% of the volatile matter in biomass industrial analysis.

[0075] In some embodiments, pyrolytic semi-coke C is fed into the gasification furnace 3-1 via a solid material conveying device 2 as a gasification feedstock for carbon gasification reaction.

[0076] In some embodiments, the reforming reactor 4 uses a reforming burner 41 to perform high-temperature gasification of the pyrolysis gas PYG generated by the pyrolysis furnace 1 and the collected unreacted solid material A (including fly ash A1 and residue A2), thus its operating temperature is 1000-1350℃. The first gasifying agent g3 introduced into the gasifying agent channel is selected from a mixture of oxygen and water vapor or carbon dioxide, or a mixture of water vapor and carbon dioxide. The oxygen concentration in the first gasifying agent g3 is 45%-100%, and the amount of oxygen introduced into the reforming reactor 4 accounts for 40%-70% of the total oxygen in the gasifying agent, wherein the total gasifying agent includes primary air g1, secondary air g4, first gasifying agent g3, and second gasifying agent g2. Furthermore, the high-temperature crude syngas PG and high-temperature ash produced by the gasification reaction in the reforming reactor 4 are connected to the interface at the top of the gasification furnace 3-1 through the bottom nozzle 42. In order to avoid the high-temperature ash from sticking to the top wall of the gasification furnace 3-1 and forming large slag blocks, the average apparent wind speed of the bottom nozzle 42 of the reforming reactor 4 is controlled at 3-15 m / s.

[0077] In some embodiments, the gasifier 3 mainly utilizes the sensible heat of the crude syngas and ash to gasify the pyrolytic semi-coke C fed into the gasifier chamber 3-1, producing gas-solid materials and bottom ash, while simultaneously reducing the temperature of the ash. Therefore, the gasification temperature within the gasifier chamber 3-1 is 800-900℃. The solid slag formed by the cooling of the bottom ash and ash constitutes a mixed slag W, which is discharged through the slag discharge port 32 at the bottom of the gasifier chamber 3-1. The gasifier 3 of this application is a turbulent fluidized bed. To enhance the turbulence and internal circulation of the gasifier chamber 3-1, the apparent fluidization velocity in the bottom dense phase zone is 2.0-4.5 m / s, and the apparent wind velocity in the upper dilute phase zone is 0.8-1.8 m / s.

[0078] In some embodiments, the gaseous and solid materials generated in the gasification furnace 3-1 are sequentially introduced into the connecting section 3-2 and the conveying section 3-3 under gas entrainment. To ensure the conveying and mixing of the gaseous and solid materials in the connecting section 3-2 while avoiding the segregation of solid particles that sink to the bottom and slagging, the apparent fluidization velocity in the connecting section 3-2 is 8-20 m / s. In the conveying section 3-3, in order to fully utilize the scouring effect of the rapidly fluidized gaseous and solid materials and to achieve the gasification reaction of the concentrated solid materials with the secondary air g4, it is necessary to reduce the velocity of the conveying section 3-3. Therefore, the apparent fluidization velocity of the conveying section 3-3 is controlled at 3-10 m / s. Furthermore, secondary air g4 is introduced into the frustum section of the conveying section 3-3 to entrain the falling unreacted solid materials to the center. The solid phase pulverizes the materials, thereby improving the gasification reaction effect of the unreacted solid materials entering the reforming reactor 4. The secondary air g4 of this application enters the transport section 3-3 through the counter-current air duct 36. The wind speed of the secondary air g4 is 60-150m / s and the oxygen concentration is 20-35%, so as to achieve collision pulverization and gasification reaction at the same time.

[0079] In some embodiments, the gaseous and solid materials sequentially enter the gas-solid separator 5 through the connecting section 3-2 and the conveying section 3-3 for gas-solid separation to obtain gaseous material D and fly ash A1. The gaseous material D includes crude syngas PG and its optional entrained residue A2.

[0080] In some embodiments, gaseous material D enters the waste heat boiler 6 for waste heat recovery and then enters the downstream dust collector 7 to capture the residue A2 in the gaseous material D to obtain pure syngas G; or gaseous material D enters the dust collector 7 to capture the residue A2 in the gaseous material D, and the obtained pure syngas G enters the downstream waste heat boiler 6 for waste heat recovery.

[0081] In some embodiments, the fly ash A1 collected by the gas-solid separator 5 can be returned to the lower middle part of the gasification furnace 3-1 via a return device for continued gasification, or it can be returned as gasification feedstock through a pipeline and enter the reforming reactor 4 through the fly ash channel of the reforming burner 41 for gasification reaction; or, the fly ash A1 collected by the gas-solid separator 5 can be mixed with part or all of the residue A2 collected by the dust collector 7 and used as gasification feedstock, entering the reforming reactor 4 through the fly ash channel of the reforming burner 41 for gasification reaction.

[0082] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A system for biomass pyrolysis gasification and energy recycling, characterized in that, include: The pyrolysis furnace (1) is divided into a lower turbulent fluidization section and an upper expansion section. It is provided with a primary air inlet (11) at the bottom of the turbulent fluidization section and a discharge port (13) for pyrolysis semi-coke (C). It is also provided with a feed port (14) for biomass (B) at the bottom of the expansion section and a pyrolysis gas (PYG) exhaust port (15) at the top. The pyrolysis semi-coke (C) and the pyrolysis gas (PYG) are generated by the pyrolysis of biomass (B). The reforming reactor (4) is provided with a reforming burner (41) connected to the exhaust port (15) at its top. The reforming burner (41) is suitable for organizing the first gasifying agent (g3), the captured unreacted solid material (A) and pyrolysis gas (PYG) to enter the reforming reactor (4) for reaction to form crude syngas and ash. The gasifier (3) includes a gasifier chamber (3-1), which is provided with a feed inlet (33) for feeding the pyrolysis semi-coke (C) and a gasifier inlet (31) at the bottom for feeding the second gasifier (g2) so that the second gasifier (g2) fluidizes the solid material fed into the gasifier chamber (3-1). The solid material includes bed material and pyrolysis semi-coke (C) as gasification feedstock. The top of the gasification furnace (3-1) is connected to the nozzle (42) at the bottom of the reforming reactor (4) so ​​that the crude syngas and the ash slag come into contact with the fluidized solid material under the push of the gas, and the sensible heat of the crude syngas and the ash slag is used to heat the gasification reaction of the pyrolysis semi-coke (C) to produce gas-solid materials and bottom slag, while reducing the temperature of the ash slag. The side wall of the gasification furnace (3-1) is also provided with a connection port (35) for the discharge of the gas-solid materials, wherein the gas-solid materials include crude syngas (PG) and unreacted solid material (A), and the unreacted solid material (A) includes fly ash (A1) and residue (A2).

2. The system according to claim 1, characterized in that, The gasifier (3) also includes: The connecting section (3-2) is inclined upward and connected to the connecting port (35) provided in the gasification furnace (3-1); The transport section (3-3) is a fluidized furnace with a water-cooled wall structure. It consists of a first vertical section, a frustum section and a second vertical section from bottom to top. The first vertical section is connected to the connecting section (3-2). The angle α between the frustum section and the horizontal plane of the first vertical section is 45°-85°.

3. The system according to claim 2, characterized in that, The system also includes: The solid material conveying device (2) is provided with a material inlet (21) connected to the discharge port (13) and a material outlet (22) connected to the feed port (33). The gas-solid separator (5) is provided with a gas-solid inlet (51) connected to the gas-solid outlet (34) of the transport section (3-3), a solid phase outlet (52) for discharging the fly ash (A1), and a gas phase outlet (53) for discharging the gas phase material (D) formed by the crude syngas (PG) and its entrained residue (A2).

4. The system according to claim 3, characterized in that, The system also includes: A waste heat boiler (6) and a dust collector (7) are sequentially arranged downstream of the gas-solid separator (5); or A dust collector (7) and a waste heat boiler (6) are arranged sequentially downstream of the gas-solid separator (5).

5. The system according to claim 4, characterized in that, The reforming burner (41) includes a central gasifying agent channel, a fly ash channel surrounding the gasifying agent channel, and a peripheral pyrolysis gas channel. This allows the first gasifying agent (g3) entering the reforming reactor (4) to preferentially react with the collected unreacted solid material (A) in a gasification reaction. The resulting mixed gas then undergoes cracking and reforming reactions with the pyrolysis gas (PYG); and / or The solid phase outlet (52) of the gas-solid separator (5) is connected to the fly ash channel of the reforming burner (41); and / or, the solid phase outlet (52) of the gas-solid separator (5) is connected to the pyrolysis furnace (1); and / or, the solid phase outlet of the gas-solid separator (5) is connected to the gasifier (3). The options also include: The dust collector (7) has an ash discharge port (73) that is connected to the fly ash channel of the reforming burner (41).

6. The system according to any one of claims 2-5, characterized in that, The conical section of the transport section (3-3) is equipped with multiple sets of opposing air ducts for secondary air (g4) to enter, which are configured to collide and pulverize the gas-solid material.

7. A method for biomass pyrolysis gasification and energy recycling, characterized in that, include: In the turbulent fluidization section at the bottom of the pyrolysis furnace (1), part of the semi-coke reacts with the introduced primary air (g1), and the released heat pyrolyzes the biomass (B) to generate pyrolysis semi-coke (C) and volatiles, the volatiles being pyrolysis gas (PYG) entrained with semi-coke. The volatiles enter the expanded section at the top of the pyrolysis furnace (1) and undergo pre-gas-solid separation to obtain pyrolysis gas (PYG). The pyrolysis gas (PYG) reacts with the first gasifying agent (g3) and the captured unreacted solid material (A) in the reforming reactor (4) under the organization of the reforming burner (41) to form crude syngas and ash. The crude syngas and the ash are propelled into the gasification furnace (3-1) by the gas, and come into contact with the fluidized solid material. The sensible heat of the crude syngas and the ash is used to heat the gasification reaction of the pyrolytic semi-coke (C), producing gas-solid material and bottom ash, while reducing the temperature of the ash. The fluidized solid material is formed by the fluidization of the second gasifying agent (g2) introduced into the gasification furnace (3-1) and the bed material and pyrolytic semi-coke (C) fed into the gasification furnace (3-1). The gas-solid material includes crude syngas (PG) and unreacted solid material (A). The unreacted solid material (A) includes fly ash (A1) and residue (A2).

8. The method according to claim 7, characterized in that, The pyrolysis semi-coke (C) is fed into the gasification furnace (3-1) via a solid material conveying device (2); Preferably, the method further includes: The gas-solid materials sequentially enter the gas-solid separator (5) through the connecting section (3-2) and the conveying section (3-3) for gas-solid separation to obtain gas phase material (D) and fly ash (A1). The gas phase material (D) includes crude syngas (PG) and its entrained residue (A2). Preferably, secondary air (g4) is introduced into the frustum section of the transport section (3-3) to carry the unreacted solid material (A) to the center and pulverize the unreacted solid material (A).

9. The method according to claim 8, characterized in that, The method further includes: The gaseous material (D) enters the waste heat boiler (6) for waste heat recovery, and then enters the downstream dust collector (7) to capture the residue (A2) in the gaseous material (D) to obtain pure syngas (G); or The gaseous material (D) enters the dust collector (7) to capture the residue (A2) in the gaseous material (D), and the resulting pure syngas (G) enters the downstream waste heat boiler (6) for waste heat recovery.

10. The method according to claim 9, characterized in that, The collected fly ash (A1), along with optionally some or all of the residue (A2), is used as gasification feedstock and enters the reforming reactor (4) through the fly ash channel of the reforming burner (41) for gasification reaction and / or The collected fly ash (A1) is fed into the pyrolysis furnace (1) as a gasification feedstock. After pre-separation in the pyrolysis furnace (1), the fine fly ash (A1) enters the reforming burner (41) for gasification, while the coarse fly ash (A1) enters the gasifier (3) via the solid material conveying device (2) for gasification. Alternatively, the collected fly ash (A1) can be fed into the gasifier (3) as a gasification feedstock for continued gasification, while also serving as a cold feedstock to cool the crude syngas (PG) and ash residue from the reforming reactor (4).

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