Device for treating pulverized coal pyrolysis flue gas, coke breeze and solid slag through circulating fluidized bed boiler

Abstract

The utility model provides a device for treating pulverized coal pyrolysis flue gas, coke breeze and solid slag by using a circulating fluidized bed boiler, which comprises a pyrolysis reactor, a charcoal burner, a gas-solid separation device, an oil-gas separation device, a filtering device, a drying device and the circulating fluidized bed boiler, an oil-gas outlet of the pyrolysis reactor is sequentially connected with the gas-solid separation device and the oil-gas separation device; a tar outlet of the oil-gas separation device is sequentially connected with the filtering device, the drying device and the circulating fluidized bed boiler; a solid phase outlet of the pyrolysis reactor is connected with the charking device, the gas returns to the pyrolysis reactor through the charking device, and a flue gas outlet of the charking device is connected with the circulating fluidized bed boiler. The circulating fluidized bed boiler is adopted to treat flue gas, solid residues and part of coke breeze generated in the pulverized coal pyrolysis process, the flue gas, the solid residues and part of coke breeze are fluidized and combusted, the heat utilization rate in the device is improved, meanwhile, the solid residues do not need to be additionally treated, the coke breeze in the flue gas is prevented from being separated, and the investment cost of the device and the waste treatment cost are effectively reduced.

Description

Technical Field

[0001] This utility model belongs to the field of coal chemical technology and relates to a device for treating flue gas, coke and solid slag from pulverized coal pyrolysis in a circulating fluidized bed boiler. Background Technology

[0002] Coal pyrolysis-based coal fractionation technology has advantages such as high energy conversion efficiency, low carbon emissions, and low water consumption. It has become the most promising technical route and industrial practice direction for clean and efficient coal conversion and utilization, and is receiving increasing attention.

[0003] Pulverized coal pyrolysis technology relies on high-volatile coal quality to convert raw coal into pyrolysis products such as coal gas, tar, and fine coke through a specific process. It also produces flue gas as a byproduct. After gas-solid separation, the oil and gas products need to be separated using an oil-gas separation tower. However, due to the limited efficiency of gas-solid separation, some fine coke is carried in the oil and gas, remaining in the tar products after oil-gas separation. The resulting solid slag is a hazardous waste product with high treatment costs. Simultaneously, the flue gas from pulverized coal pyrolysis also carries some fine coke. After gas-solid separation, the remaining flue gas is fed into a waste heat boiler for combustion. However, even after gas-solid separation, fine coke remains in the flue gas, leading to severe ash accumulation in the waste heat boiler after a period of operation, affecting heat exchange efficiency and preventing the unit from operating for extended periods.

[0004] CN 110423627A discloses a pyrolysis device and method for carbonaceous materials with a dual-circulation gas-solid heat carrier. The device includes a feeding unit, a vertical tube pyrolysis reactor, a charcoal burner, a gas-solid separation unit, and a gas-liquid separation unit. The feeding unit includes a grinding device and a particle classifier. The lower outlet of the particle classifier is connected to the inlet of the vertical tube pyrolysis reactor. The vertical tube pyrolysis reactor extends upwards into the gas-solid separation unit. The bottom outlet of the gas-solid separation unit is connected to the charcoal burner, and the bottom outlet of the charcoal burner is connected to the vertical tube pyrolysis reactor. The gas-solid separation unit includes a settling tank, and the bottom of the settling tank is sequentially connected to a steam generator and a coke cooler. The gas-liquid separation unit includes an oil washing tower. This device does not further process the tar obtained from gas-liquid separation, i.e., it does not address the treatment of any solid residues that may be present in the tar. Furthermore, the flue gas from the charcoal burner can be connected to a waste heat boiler for heat exchange, but it does not address the impact of coke accumulation in the flue gas on the operation of the waste heat boiler.

[0005] CN 111442261A discloses a combustion system and operating method for an upward-bed coal pyrolysis co-production circulating fluidized bed boiler. The device includes a pulverized coal silo, a silo pump, an upward-bed pyrolysis furnace, a turbulent coalescing device, a high-temperature centrifuge, a cyclone separator, a pyrolysis oil and gas cooling device, a pyrolysis oil and gas purification and separation device, a pyrolysis gas collector, a pyrolysis water collector, a pyrolysis tar collector, and a circulating fluidized bed boiler. The upward-bed pyrolysis furnace is equipped with a pulverized coal inlet, a heat carrier inlet, a guide tube, a guide zone, an annular gap zone, a lifting gas inlet, a wind chamber, an air distribution plate, and a bottom ash outlet. The bottom outlet of the cyclone separator is connected to both the heat carrier inlet and the circulating fluidized bed boiler, and the bottom ash outlet is also connected to the circulating fluidized bed boiler. This patent describes fluidized combustion of the semi-coke and heat carrier in the pulverized coal pyrolysis products, but does not address the treatment of solid residues in the tar products, nor does it specify the treatment of the flue gas generated by pyrolysis.

[0006] In summary, the treatment of pyrolysis products of pulverized coal is mainly carried out using circulating fluidized bed boilers. By separating the various pyrolysis products, pulverized coke, flue gas, and solid slag are co-fluidized and burned with the raw materials to improve the energy utilization efficiency of the pyrolysis products and reduce their treatment costs. Utility Model Content

[0007] To address the problems existing in the prior art, the purpose of this utility model is to provide a device for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag using a circulating fluidized bed boiler. The device separates the pulverized coal pyrolysis products and uses a circulating fluidized bed boiler to fluidize and burn the generated flue gas, solid slag, and part of the pulverized coke, thereby improving the heat utilization rate within the device. At the same time, it eliminates the need for additional treatment of solid residues, avoids the separation of pulverized coke particles in the flue gas, and effectively reduces the investment cost of the device and the waste treatment cost.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] This utility model provides a device for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler. The device includes a pyrolysis reactor, a charcoal burner, a gas-solid separation device, an oil-gas separation device, a filtration device, a drying device, and a circulating fluidized bed boiler. The oil-gas outlet of the pyrolysis reactor is connected to the inlet of the gas-solid separation device, the gas phase outlet of the gas-solid separation device is connected to the inlet of the oil-gas separation device, the tar outlet of the oil-gas separation device is connected to the inlet of the filtration device, and the solid slag outlet of the filtration device is connected to the inlet of the circulating fluidized bed boiler via the drying device.

[0010] The first coke outlet of the pyrolysis reactor is connected to the inlet of the charcoal burner, the solid phase outlet of the charcoal burner is connected to the inlet of the pyrolysis reactor, the flue gas outlet of the charcoal burner is connected to the inlet of the circulating fluidized bed boiler, and the solid phase outlet of the gas-solid separation device is connected to the inlet of the circulating fluidized bed boiler.

[0011] In this invention, the pyrolysis process of pulverized coal yields coke, coal gas, and tar after separation, each with its own applications. Simultaneously, flue gas and solid slag are produced as byproducts. This invention employs a circulating fluidized bed boiler to treat the dust-laden flue gas and solid slag in the tar during the pyrolysis process. The byproduct flue gas can be directly introduced into the fluidized bed boiler for utilization, eliminating the need for additional separation equipment. This reduces equipment investment and ensures that the fine coke does not accumulate ash under the fluidization of the flue gas, achieving the goal of long-term operation of the device. The fine coke remaining in the tar products, after filtration, becomes solid slag, which is a hazardous waste product. After drying, it is directly fed into the circulating fluidized bed boiler for combustion, effectively solving the problem of solid slag disposal. Simultaneously, the combustion heat is used to generate steam, achieving comprehensive utilization of heat within the device. The device has a simple structure, low investment and operating costs, and achieves rapid treatment of solid waste with high economic benefits.

[0012] The following are preferred technical solutions of this utility model, but are not intended to limit the technical solutions provided by this utility model. Through the following technical solutions, the technical objectives and beneficial effects of this utility model can be better achieved and realized.

[0013] As a preferred technical solution of this utility model, the pyrolysis reactor is provided with a pulverized coal inlet, the pulverized coal inlet is connected to a pulverized coal conveying pipeline, and the pulverized coal conveying pipeline is provided with a pneumatic conveying device.

[0014] The solid phase outlet of the charcoal burner is connected to the pulverized coal conveying pipeline of the pyrolysis reactor.

[0015] As a preferred technical solution of this utility model, the pyrolysis reactor is further provided with a second coke powder outlet, which is connected to the inlet of the circulating fluidized bed boiler.

[0016] As a preferred technical solution of this utility model, the flue gas discharged from the charcoal burner carries coke particles with a particle size of less than 50μm, such as 50μm, 45μm, 40μm, 35μm, 30μm, 25μm, 20μm, 18μm, 15μm, 12μm or 10μm, but not limited to the listed values. Other unlisted values ​​within this range are also applicable. The flue gas and coke particles are jointly fed into a circulating fluidized bed boiler as raw material gas or fluidizing gas.

[0017] In this invention, the pulverized coal is transported to the pyrolysis reactor by a pneumatic conveying device. The pulverized coal undergoes a complex chemical reaction in the pyrolysis reactor to generate coke powder and oil gas. The coke powder enters the charcoal burner for partial combustion, heating the coke powder in the charcoal burner. By adjusting the amount of coke powder entering the charcoal burner, a fluidized bed is formed and partial combustion is achieved, releasing a large amount of heat to heat the coke powder in the charcoal burner. Part of the obtained high-temperature coke powder is sent out as a product, and the other part is used as a heat carrier to mix with the raw pulverized coal, providing a heat source for the pyrolysis reaction.

[0018] The flue gas produced by the combustion of pulverized coke in the charcoal burner still carries some fine pulverized coke after separation. It can be directly fed into the circulating fluidized bed boiler as raw material gas or fluidizing gas. At the same time, some pulverized coke can also leave directly from the pyrolysis reactor without passing through the charcoal burner and be used as raw material for the circulating fluidized bed boiler. Through complete combustion in the circulating fluidized bed boiler, the heat generated heats the boiler water to produce steam, realizing the comprehensive utilization of pyrolysis products.

[0019] As a preferred technical solution of this utility model, the gas-solid separation device includes a cyclone separator, and the oil-gas separation device includes an oil-gas separation tower. The upper part of the oil-gas separation tower is provided with a gas outlet, and the lower part is provided with a tar outlet.

[0020] As a preferred technical solution of this utility model, the filtration device includes a screen filter and / or a centrifuge. The particle size of the solid residue obtained after filtration by the filtration device is less than 20μm, such as 20μm, 18μm, 15μm, 12μm, 10μm, 8μm, 5μm, 2μm or 1μm, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0021] In this invention, the solid particles in the tar are small, but the solid particles will agglomerate and grow in the oil, thereby reducing the requirements for the precision of the filter. By first using a filter screen structure and then centrifuging to separate the solid particles in the tar, the solid particles in the tar can be basically intercepted and separated.

[0022] As a preferred technical solution of this utility model, the solid slag obtained by the filtration device enters the drying device through the first feeding device, and the dried solid slag discharged from the drying device enters the circulating fluidized bed boiler through the second feeding device.

[0023] The first feeding device and the second feeding device independently include a screw conveyor or a belt conveyor.

[0024] As a preferred embodiment of this invention, the gas inlet of the drying device is connected to the flue gas outlet of the charcoal burner or the circulating fluidized bed boiler, and the gas outlet of the drying device is connected to the inlet of the circulating fluidized bed boiler.

[0025] As a preferred technical solution of this utility model, the device further includes a fan, and the gas inlet of the drying device is connected to the combustion gas inlet of the circulating fluidized bed boiler via the fan.

[0026] In this invention, the oil and gas products generated by the pyrolysis reactor are separated by gas-solid separation to separate some of the coke powder carried in the oil and gas. Then, the pyrolysis gas and tar are separated by oil-gas separation. The solid residue in the tar is then filtered out. The filtered solid residue is dried by a drying device and then transported to the fluidized bed of the circulating fluidized bed boiler for combustion. The heat source of the drying device comes from the high-temperature flue gas of the charcoal burner or the circulating fluidized bed boiler. The generated dry gas is then sent to the circulating fluidized bed boiler by a blower for fluidized combustion.

[0027] As a preferred technical solution of this utility model, the circulating fluidized bed boiler is provided with a demineralized water inlet and a steam outlet.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] (1) The device described in this utility model uses a circulating fluidized bed boiler to treat the dust-containing flue gas and solid slag generated during the pyrolysis of pulverized coal. The by-product flue gas can be introduced into the fluidized bed boiler for direct use without the need for additional separation equipment. This can reduce equipment investment and ensure that fine coke will not accumulate ash under the fluidization of flue gas, thus achieving the purpose of long-term operation of the device.

[0030] (2) The fine coke residue remaining in the tar product of this utility model becomes solid slag after filtration. It is a hazardous waste product. After drying, it is directly fed into the circulating fluidized bed boiler for combustion, which can effectively solve the problem of where the solid slag goes. At the same time, the heat of combustion is used to generate steam, realizing the comprehensive utilization of heat in the device.

[0031] (3) The device described in this utility model has a simple structure, low investment and operating costs, and achieves rapid treatment of solid waste, resulting in high economic benefits. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the circulating fluidized bed boiler device for treating pulverized coal pyrolysis flue gas, pulverized coke and solid slag provided in Embodiment 1 of this utility model;

[0033] Among them, 1-pyrolysis reactor; 2-charcoal burner; 3-gas-solid separation device; 4-oil-gas separation device; 5-filtration device; 6-drying device; 7-circulating fluidized bed boiler; 8-fan. Detailed Implementation

[0034] To better illustrate this utility model and facilitate understanding of its technical solution, the present utility model is further described in detail below. However, the following embodiments are merely simplified examples of this utility model and do not represent or limit the scope of protection of this utility model. The scope of protection of this utility model is determined by the claims.

[0035] The following are typical but non-limiting embodiments of this utility model:

[0036] Example 1:

[0037] This embodiment provides a device for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler. A schematic diagram of the device is shown below. Figure 1 As shown, the system includes a pyrolysis reactor 1, a charcoal burner 2, a gas-solid separation device 3, an oil-gas separation device 4, a filtration device 5, a drying device 6, and a circulating fluidized bed boiler 7. The oil-gas outlet of the pyrolysis reactor 1 is connected to the inlet of the gas-solid separation device 3, the gas phase outlet of the gas-solid separation device 3 is connected to the inlet of the oil-gas separation device 4, the tar outlet of the oil-gas separation device 4 is connected to the inlet of the filtration device 5, and the solid slag outlet of the filtration device 5 is connected to the inlet of the circulating fluidized bed boiler 7 via the drying device 6.

[0038] The first coke outlet of the pyrolysis reactor 1 is connected to the inlet of the charcoal burner 2, the solid phase outlet of the charcoal burner 2 is connected to the inlet of the pyrolysis reactor 1, the flue gas outlet of the charcoal burner 2 is connected to the inlet of the circulating fluidized bed boiler 7, and the solid phase outlet of the gas-solid separation device 3 is connected to the inlet of the circulating fluidized bed boiler 7.

[0039] The pyrolysis reactor 1 is provided with a pulverized coal inlet, which is connected to a pulverized coal conveying pipeline, and the pulverized coal conveying pipeline is provided with a pneumatic conveying device.

[0040] The solid phase outlet of the charcoal burner 2 is connected to the pulverized coal conveying pipeline of the pyrolysis reactor 1.

[0041] The pyrolysis reactor 1 is also provided with a second coke outlet, which is connected to the inlet of the circulating fluidized bed boiler 7.

[0042] The flue gas discharged from the charcoal burner 2 carries coke particles with a particle size of less than 45 μm. The flue gas and coke particles are fed into the circulating fluidized bed boiler 7 as raw material gas.

[0043] The gas-solid separation device 3 is a cyclone separator, and the oil-gas separation device 4 is an oil-gas separation tower. The upper part of the oil-gas separation tower is provided with a gas outlet, and the lower part is provided with a tar outlet.

[0044] The filtration device 5 is a screen filter, and the particle size of the solid residue obtained after filtration by the filtration device 5 is less than 20 μm.

[0045] The solid residue obtained by the filtration device 5 enters the drying device 6 through the first feeding device, and the dried solid residue discharged from the drying device 6 enters the circulating fluidized bed boiler 7 through the second feeding device.

[0046] Both the first feeding device and the second feeding device are screw conveyors.

[0047] The gas inlet of the drying device 6 is connected to the flue gas outlet of the charcoal burner 2, and the gas outlet of the drying device 6 is connected to the inlet of the circulating fluidized bed boiler 7.

[0048] The device also includes a fan 8, and the gas inlet of the drying device 6 is connected to the combustion gas inlet of the circulating fluidized bed boiler 7 via the fan 8.

[0049] The circulating fluidized bed boiler 7 is equipped with a demineralized water inlet and a steam outlet.

[0050] Example 2:

[0051] This embodiment provides a circulating fluidized bed boiler apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag. The apparatus includes a pyrolysis reactor 1, a charcoal burner 2, a gas-solid separation device 3, an oil-gas separation device 4, a filtration device 5, a drying device 6, and a circulating fluidized bed boiler 7. The oil-gas outlet of the pyrolysis reactor 1 is connected to the inlet of the gas-solid separation device 3, the gas phase outlet of the gas-solid separation device 3 is connected to the inlet of the oil-gas separation device 4, the tar outlet of the oil-gas separation device 4 is connected to the inlet of the filtration device 5, and the solid slag outlet of the filtration device 5 is connected to the inlet of the circulating fluidized bed boiler 7 via the drying device 6.

[0052] The first coke outlet of the pyrolysis reactor 1 is connected to the inlet of the charcoal burner 2, the solid phase outlet of the charcoal burner 2 is connected to the inlet of the pyrolysis reactor 1, the flue gas outlet of the charcoal burner 2 is connected to the inlet of the circulating fluidized bed boiler 7, and the solid phase outlet of the gas-solid separation device 3 is connected to the inlet of the circulating fluidized bed boiler 7.

[0053] The pyrolysis reactor 1 is provided with a pulverized coal inlet, which is connected to a pulverized coal conveying pipeline, and the pulverized coal conveying pipeline is provided with a pneumatic conveying device.

[0054] The solid phase outlet of the charcoal burner 2 is connected to the pulverized coal conveying pipeline of the pyrolysis reactor 1.

[0055] The pyrolysis reactor 1 is also provided with a second coke outlet, which is connected to the inlet of the circulating fluidized bed boiler 7.

[0056] The flue gas discharged from the charcoal burner 2 carries coke particles with a particle size of less than 40 μm. The flue gas and coke particles are fed into the circulating fluidized bed boiler 7 as fluidizing gas.

[0057] The gas-solid separation device 3 is a cyclone separator, and the oil-gas separation device 4 is an oil-gas separation tower. The upper part of the oil-gas separation tower is provided with a gas outlet, and the lower part is provided with a tar outlet.

[0058] The filtration device 5 is a centrifuge, and the particle size of the solid residue obtained after filtration by the filtration device 5 is less than 15 μm.

[0059] The solid residue obtained by the filtration device 5 enters the drying device 6 through the first feeding device, and the dried solid residue discharged from the drying device 6 enters the circulating fluidized bed boiler 7 through the second feeding device.

[0060] Both the first feeding device and the second feeding device are belt conveyors.

[0061] The gas inlet of the drying device 6 is connected to the flue gas outlet of the circulating fluidized bed boiler 7, and the gas outlet of the drying device 6 is connected to the inlet of the circulating fluidized bed boiler 7.

[0062] The device also includes a fan 8, and the gas inlet of the drying device 6 is connected to the combustion gas inlet of the circulating fluidized bed boiler 7 via the fan 8.

[0063] The circulating fluidized bed boiler 7 is equipped with a demineralized water inlet and a steam outlet.

[0064] Example 3:

[0065] This embodiment provides a circulating fluidized bed boiler apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag. The apparatus includes a pyrolysis reactor 1, a charcoal burner 2, a gas-solid separation device 3, an oil-gas separation device 4, a filtration device 5, a drying device 6, and a circulating fluidized bed boiler 7. The oil-gas outlet of the pyrolysis reactor 1 is connected to the inlet of the gas-solid separation device 3, the gas phase outlet of the gas-solid separation device 3 is connected to the inlet of the oil-gas separation device 4, the tar outlet of the oil-gas separation device 4 is connected to the inlet of the filtration device 5, and the solid slag outlet of the filtration device 5 is connected to the inlet of the circulating fluidized bed boiler 7 via the drying device 6.

[0066] The first coke outlet of the pyrolysis reactor 1 is connected to the inlet of the charcoal burner 2, the solid phase outlet of the charcoal burner 2 is connected to the inlet of the pyrolysis reactor 1, the flue gas outlet of the charcoal burner 2 is connected to the inlet of the circulating fluidized bed boiler 7, and the solid phase outlet of the gas-solid separation device 3 is connected to the inlet of the circulating fluidized bed boiler 7.

[0067] The pyrolysis reactor 1 is provided with a pulverized coal inlet, which is connected to a pulverized coal conveying pipeline, and the pulverized coal conveying pipeline is provided with a pneumatic conveying device.

[0068] The solid phase outlet of the charcoal burner 2 is connected to the pulverized coal conveying pipeline of the pyrolysis reactor 1.

[0069] The flue gas discharged from the charcoal burner 2 carries coke particles with a particle size of less than 30 μm. The flue gas and coke particles are fed into the circulating fluidized bed boiler 7 as raw material gas.

[0070] The gas-solid separation device 3 is a cyclone separator, and the oil-gas separation device 4 is an oil-gas separation tower. The upper part of the oil-gas separation tower is provided with a gas outlet, and the lower part is provided with a tar outlet.

[0071] The filtration device 5 consists of a screen filter and a centrifuge. The particle size of the solid residue obtained after filtration by the filtration device 5 is less than 10 μm.

[0072] The solid residue obtained by the filtration device 5 enters the drying device 6 through the first feeding device, and the dried solid residue discharged from the drying device 6 enters the circulating fluidized bed boiler 7 through the second feeding device.

[0073] Both the first feeding device and the second feeding device are screw conveyors.

[0074] The gas inlet of the drying device 6 is connected to the flue gas outlet of the charcoal burner 2, and the gas outlet of the drying device 6 is connected to the inlet of the circulating fluidized bed boiler 7.

[0075] The circulating fluidized bed boiler 7 is equipped with a demineralized water inlet and a steam outlet.

[0076] The apparatus described in the above embodiments is used for the separation and treatment of pulverized coal pyrolysis products, with a circulating fluidized bed boiler as the main equipment, to process pulverized coal pyrolysis flue gas, pulverized coke, and solid slag. Specifically, it includes:

[0077] The pulverized coal undergoes a complex chemical reaction in the pyrolysis reactor to produce coke powder and oil gas. The coke powder enters the charcoal burner for partial combustion, heating the coke powder in the burner. Part of the resulting high-temperature coke powder is sent out as a product, while the other part is used as a heat carrier to mix with the raw pulverized coal, providing a heat source for the pyrolysis reaction. The flue gas generated by the combustion of coke powder in the burner, after separation, still carries some fine coke powder and can be directly fed into the circulating fluidized bed boiler as feed gas or fluidizing gas. At the same time, some coke powder can also leave the pyrolysis reactor directly without passing through the burner and be used as feed gas for the circulating fluidized bed boiler.

[0078] The oil and gas products generated by the pyrolysis reactor are separated by gas-solid separation to remove some of the coke powder carried in the oil and gas. Then, the pyrolysis gas is separated from the tar by oil-gas separation. The solid residue in the tar is then filtered out. The filtered solid residue is dried by a drying device and then transported to the fluidized bed of the circulating fluidized bed boiler for combustion. The heat source for the drying device comes from the high-temperature flue gas from the charcoal burner or the circulating fluidized bed boiler. The generated dry gas is then sent to the circulating fluidized bed boiler by a blower for fluidized combustion. Through the complete combustion of the above products in the circulating fluidized bed boiler, the heat generated heats the boiler water to produce steam, realizing the comprehensive utilization of the pyrolysis products.

[0079] As can be seen from the above embodiments, the device of this utility model utilizes a circulating fluidized bed boiler to treat the dust-laden flue gas and solid slag generated during the pyrolysis of pulverized coal. The by-product flue gas can be directly introduced into the fluidized bed boiler for use, eliminating the need for additional separation equipment. This reduces equipment investment and ensures that the fine coke does not accumulate ash under the fluidization of the flue gas, achieving the goal of long-term operation of the device. The fine coke residue remaining in the tar product of this utility model becomes solid slag after filtration, which is a hazardous waste product. After drying, it is directly fed into the circulating fluidized bed boiler for combustion, effectively solving the problem of solid slag disposal. At the same time, the heat from combustion is used to generate steam, realizing the comprehensive utilization of heat within the device. The device has a simple structure, low investment and operating costs, achieves rapid treatment of solid waste, and has high economic benefits.

[0080] The applicant declares that this utility model is illustrated through the above embodiments, but it is not limited to the above-described detailed device, meaning that this utility model does not necessarily rely on the above-described detailed device to be implemented. Those skilled in the art should understand that any improvements to this utility model, equivalent substitutions for the device, additions of auxiliary devices, and selection of specific methods, etc., all fall within the protection and disclosure scope of this utility model.

Claims

1. A device for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler, characterized in that, The apparatus includes a pyrolysis reactor, a charcoal burner, a gas-solid separation device, an oil-gas separation device, a filtration device, a drying device, and a circulating fluidized bed boiler. The oil-gas outlet of the pyrolysis reactor is connected to the inlet of the gas-solid separation device, the gas phase outlet of the gas-solid separation device is connected to the inlet of the oil-gas separation device, the tar outlet of the oil-gas separation device is connected to the inlet of the filtration device, and the solid slag outlet of the filtration device is connected to the inlet of the circulating fluidized bed boiler via the drying device. The first coke outlet of the pyrolysis reactor is connected to the inlet of the charcoal burner, the solid phase outlet of the charcoal burner is connected to the inlet of the pyrolysis reactor, the flue gas outlet of the charcoal burner is connected to the inlet of the circulating fluidized bed boiler, and the solid phase outlet of the gas-solid separation device is connected to the inlet of the circulating fluidized bed boiler.

2. The apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler according to claim 1, characterized in that, The pyrolysis reactor is provided with a pulverized coal inlet, which is connected to a pulverized coal conveying pipeline, and the pulverized coal conveying pipeline is provided with a pneumatic conveying device. The solid phase outlet of the charcoal burner is connected to the pulverized coal conveying pipeline of the pyrolysis reactor.

3. The apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler according to claim 1, characterized in that, The pyrolysis reactor is also equipped with a second coke outlet, which is connected to the inlet of the circulating fluidized bed boiler.

4. The apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler according to claim 1, characterized in that, The flue gas discharged from the charcoal burner carries coke particles with a particle size of less than 50 μm. The flue gas and coke particles are fed into a circulating fluidized bed boiler as raw material gas or fluidizing gas.

5. The apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler according to claim 1, characterized in that, The gas-solid separation device includes a cyclone separator, and the oil-gas separation device includes an oil-gas separation tower. The upper part of the oil-gas separation tower is provided with a gas outlet, and the lower part is provided with a tar outlet.

6. The apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler according to claim 1, characterized in that, The filtration device includes a screen filter and / or a centrifuge, and the particle size of the solid residue obtained after filtration is less than 20 μm.

7. The apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler according to claim 1, characterized in that, The solid residue obtained by the filtration device enters the drying device through the first feeding device, and the dried solid residue discharged from the drying device enters the circulating fluidized bed boiler through the second feeding device. The first feeding device and the second feeding device independently include a screw conveyor or a belt conveyor.

8. The apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler according to claim 1, characterized in that, The gas inlet of the drying device is connected to the flue gas outlet of the charcoal burner or the circulating fluidized bed boiler, and the gas outlet of the drying device is connected to the inlet of the circulating fluidized bed boiler.

9. The apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler according to claim 8, characterized in that, The device also includes a fan, and the gas outlet of the drying device is connected to the combustion gas inlet of the circulating fluidized bed boiler via the fan.

10. The apparatus for treating pulverized coal pyrolysis flue gas, pulverized coke, and solid slag in a circulating fluidized bed boiler according to claim 1, characterized in that, The circulating fluidized bed boiler is equipped with a demineralized water inlet and a steam outlet.

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