Integrated device of pulverized coal pyrolysis, circulating fluidized bed boiler and gasification furnace

Abstract

The utility model provides a pulverized coal pyrolysis, circulating fluidized bed boiler and gasification furnace integrated device which comprises a pyrolysis unit, a heat carrier heating unit, a powder selecting unit, a circulating fluidized bed boiler unit and a gasification unit, a solid phase outlet of the pyrolysis unit is independently connected with the heat carrier heating unit and the powder selecting unit, and a solid phase outlet of the gasification unit is independently connected with the circulating fluidized bed boiler unit. A smoke outlet pipeline of the heat carrier heating unit is connected with the powder selecting unit and the circulating fluidized bed boiler unit, an upper outlet of the powder selecting unit is connected with the gasification unit, and a lower outlet of the powder selecting unit is connected with the circulating fluidized bed boiler unit. According to the utility model, the particle size of the coke breeze after pulverized coal pyrolysis is graded, the graded coke breeze with smaller particle size is used for gasification, and the coke breeze with larger particle size is used as the fuel of the circulating fluidized bed boiler, so as to meet the requirements of different devices on the particle size of the coke breeze, effectively improve the utilization rate of the coke breeze, maximally utilize sensible heat of the coke breeze and realize efficient recycling of energy; and the treatment cost of downstream coke breeze processing is reduced, and efficient graded and quality-divided utilization of coke breeze is truly realized.

Description

Technical Field

[0001] This utility model belongs to the field of coal chemical technology and relates to an integrated device for pulverized coal pyrolysis, circulating fluidized bed boiler, and gasifier. Background Technology

[0002] Given the significant proportion of coal in my country's energy production and consumption structure, developing comprehensive coal pyrolysis utilization technology is of paramount strategic importance for alleviating my country's energy shortage and improving its energy structure. Coal pyrolysis technology fully utilizes the hydrocarbon organic matter contained in coal to decompose raw coal into primary products such as coal gas, tar, and pulverized semi-coke. It features low energy consumption, low carbon emissions, and low material consumption, making it an important pathway for the clean and efficient utilization of coal. With the increasing mechanization of coal mining, pulverized coal production has been increasing year by year, thus pulverized coal pyrolysis has become a research hotspot in recent years.

[0003] The pyrolysis of pulverized coal generates a large amount of coke powder. Further utilization of this coke powder is a key step in improving product yield and the overall value of pulverized coal. Currently, the utilization of pyrolysis coke powder includes using it as a coke product, as a circulating heat carrier, as a gasification feedstock, or as a feedstock for circulating fluidized bed boilers. Although there are many utilization pathways, the requirements for the coke powder vary. If the raw material particle size, temperature, and other process conditions are unsuitable, it can easily lead to low utilization rates, substandard product quality, or the inability of the equipment to operate stably for extended periods, thus hindering the efficient utilization of pulverized coal through grading and quality differentiation.

[0004] CN 101063039A discloses a graded clean multi-stage utilization technology for pulverized coal with pyrolysis as the first stage. The technology includes a fluidized bed drying pyrolysis unit, a multi-circulation fluidized bed gasification unit, a circulating fluidized bed boiler, and a combined heat and power system. It consists of drying pyrolysis, gasification, and combustion processes. After raw coal processing and screening, pulverized coal enters the fluidized bed drying pyrolysis unit for drying and pyrolysis. The high-carbon semi-coke powder after pyrolysis undergoes a multi-circulation fluidized bed gasification reaction. The generated syngas enters chemical production, and then the ash coke with low solid carbon content is sent to the circulating fluidized bed boiler for complete combustion. The key to this system lies in the pyrolysis and gasification units, especially the pneumatic conveying device, separation settling chamber, and gasification bed structure in the gasification unit, which enables multi-circulation gasification of pulverized coal. However, the particle size of the coke feedstock entering the gasification unit is not controlled, which is detrimental to improving the utilization rate of the coke. The system has a complex structure, high requirements for operating conditions, and high equipment and process costs.

[0005] CN 204151306U discloses a coal pyrolysis gasification combined production system based on a circulating fluidized bed (CFB). This system includes a CFB boiler, a pyrolysis coal hopper, a moving bed pyrolysis reactor, a screener, a semi-coke distributor, a moving bed gasifier, a cyclone separator, and an activated semi-coke screener. The high-temperature circulating ash outlet of the CFB boiler is connected to the moving bed pyrolysis reactor, the pyrolysis gas outlet is connected to the moving bed gasifier, the solid product outlet is connected to the screener, and the oversize outlet is connected to the semi-coke distributor. The semi-coke distributor is connected to both the moving bed gasifier and the cyclone separator. This device also involves the three processes of coal pyrolysis, gasification, and combustion. However, in this system, the powdered semi-coke and circulating ash from the pyrolysis solid products enter the CFB boiler, while the larger-particle-size granular semi-coke enters the gasifier. This does not meet the requirements for gasification feedstock under normal circumstances and is detrimental to improving the utilization rate of powdered coke.

[0006] In summary, for the utilization of coke products after pulverized coal pyrolysis, it is necessary to classify the coke by particle size and then process the coke of different particle sizes appropriately to improve the utilization rate of coke and energy recovery rate, reduce processing costs, and achieve efficient graded and quality-based utilization of coke. Utility Model Content

[0007] To address the problems existing in the prior art, the purpose of this utility model is to provide an integrated device for pulverized coal pyrolysis, circulating fluidized bed boiler, and gasifier. The device classifies the coke particles after pulverized coal pyrolysis by particle size. The smaller coke particles are directly used for gasification, while the larger coke particles are used as fuel for the circulating fluidized bed boiler. This not only effectively utilizes the heat carried by the coke particles but also improves the utilization rate of the coke particles and reduces the processing costs of subsequent coke processing, truly achieving efficient classification and quality-based utilization of coke particles.

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

[0009] This utility model provides an integrated device for pulverized coal pyrolysis, circulating fluidized bed boiler, and gasifier. The integrated device includes a pyrolysis unit, a heat carrier heating unit, a pulverized coal classifier unit, a circulating fluidized bed boiler unit, and a gasification unit. The solid phase outlet of the pyrolysis unit is independently connected to the inlet of the heat carrier heating unit and the inlet of the pulverized coal classifier unit. The flue gas outlet pipeline of the heat carrier heating unit is divided into two branches, which are respectively connected to the inlet of the pulverized coal classifier unit and the inlet of the circulating fluidized bed boiler unit. The upper outlet of the pulverized coal classifier unit is connected to the inlet of the gasification unit, and the lower outlet of the pulverized coal classifier unit is connected to the inlet of the circulating fluidized bed boiler unit.

[0010] In this invention, the coke produced by pulverized coal pyrolysis, after meeting the requirement of its use as a heat carrier to maintain the pyrolysis process, can be further utilized. Given its particle size distribution, using all of it in a single process would not achieve full utilization. Therefore, this invention employs a particle size classification unit to classify the coke, ensuring that the two portions of coke after classification are suitable for their respective applications. Specifically, the smaller coke particles are used in gasification processes to produce syngas, while the larger coke particles can be used as fuel in circulating fluidized bed boilers, utilizing their combustion heat to produce steam for power generation. These two utilization methods can meet the particle size requirements of different devices, thereby effectively improving the utilization rate of coke and maximizing the use of its sensible heat, achieving efficient energy recovery and utilization of the system. Simultaneously, it reduces the pretreatment costs of downstream coke processing, truly realizing efficient graded and differentiated utilization of coke. The device has a reasonable structural design, and its coal utilization is clean and efficient, contributing to the large-scale development of pulverized coal pyrolysis devices and creating conditions for the large-scale development of the downstream industrial chain.

[0011] 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.

[0012] As a preferred technical solution of this utility model, the pyrolysis unit includes a pyrolysis reactor, and a first gas-solid separator is provided in the upper part of the pyrolysis reactor.

[0013] The first gas-solid separator includes at least one cyclone separator, such as a single-stage, two-stage, or three-stage separator.

[0014] In this invention, pulverized coal raw material is mixed with circulating coal gas and heat carrier and then enters a pyrolysis reactor. The particle size of the pulverized coal raw material is less than 1 mm, such as 1 mm, 0.9 mm, 0.8 mm, 0.6 mm, 0.5 mm, 0.3 mm, 0.2 mm or 0.1 mm, etc. The pyrolysis reaction temperature is 500-550℃, such as 500℃, 510℃, 520℃, 530℃, 540℃ or 550℃, etc. The reaction produces coke and pulverized coke, which undergo gas-solid separation in a cyclone separator at the top of the reactor. The resulting oil and gas are sent to a downstream unit for oil and gas separation.

[0015] As a preferred technical solution of this utility model, the heat carrier heating unit includes a heat carrier heater and a flue gas generator. The flue gas generator is provided with a fuel inlet and an air inlet, and the outlet of the flue gas generator is connected to the lower inlet of the heat carrier heater.

[0016] The first coke outlet of the pyrolysis unit is connected to the lower inlet of the heat carrier heater via a heat carrier circulation pipe, and the bottom outlet of the heat carrier heater is connected to the feed pipe of the pyrolysis unit.

[0017] As a preferred technical solution of this utility model, a second gas-solid separator is provided in the upper part of the heat carrier heater. The second gas-solid separator includes at least one stage of cyclone separator, such as one stage, two stages or three stages.

[0018] In this invention, a portion of the pyrolysis-obtained coke powder enters the heat carrier heater through a heat carrier circulation pipe, where it undergoes oxygen-deficient combustion with the flue gas from the flue gas generator, heating the coke powder. The heated coke powder is then mixed with pulverized coal and circulating coal gas under gravity, serving as a heat carrier to supply heat for the pyrolysis reaction.

[0019] As a preferred technical solution of this utility model, the powder classification unit includes a powder classifier, the second coke outlet of the pyrolysis unit is connected to the inlet of the powder classifier, and one of the flue gas outlet pipes of the heat carrier heater is connected to the inlet pipe of the powder classifier, and enters the powder classifier together with the coke.

[0020] As a preferred technical solution of this utility model, the air classifier is equipped with a grading rotor or filter screen to separate coke powder into fine coke powder and coarse coke powder. The particle size of the fine coke powder is below 180-220μm, such as below 220μm, below 210μm, below 200μm, below 190μm, or below 180μm, etc. The particle size of the coarse coke powder is above 180-220μm, such as above 180μm, above 190μm, above 200μm, above 210μm, or above 220μm, etc.; however, it is not limited to the listed values, and other unlisted values ​​within their respective ranges are also applicable.

[0021] In this invention, another portion of the coke produced by pulverized coal pyrolysis enters the classifier of the classifier unit from the bottom of the pyrolysis reactor. After being lifted to the classification zone by the flue gas from the heat carrier heater, it is classified, and the coarse coke and fine coke are used in different processes. When the classifier is equipped with a classification rotor, the structure of the classification rotor is similar to a bladed drum, which is fixed inside the classifier and can be called a classification impeller. By controlling the rotation speed of the classification rotor to 60-110 r / min, such as 60 r / min, 70 r / min, 80 r / min, 90 r / min, 100 r / min or 110 r / min, the coke particles are classified to obtain the aforementioned fine coke and coarse coke.

[0022] As a preferred technical solution of this utility model, the circulating fluidized bed boiler unit includes a coke buffer tank and a circulating fluidized bed boiler. The coarse coke outlet at the bottom of the classifier is connected to the inlet of the coke buffer tank, and the outlet of the coke buffer tank is connected to the inlet of the circulating fluidized bed boiler.

[0023] As a preferred technical solution of this utility model, the circulating fluidized bed boiler is provided with a flue gas inlet, a deoxygenated water inlet, a steam outlet, a combustion flue gas outlet, and an ash outlet. Another flue gas outlet pipeline of the heat carrier heater is connected to the lower flue gas inlet of the circulating fluidized bed boiler.

[0024] In this invention, the classifier is arranged close to the circulating fluidized bed boiler unit, so that the coarse coke after classification by the classifier is discharged to the coke buffer tank by gravity, and then directly transported to the furnace of the circulating fluidized bed boiler. The coke buffer tank is set up to take into account the fluctuation of the pyrolysis unit, so as to achieve continuous and stable feeding of coke to the circulating fluidized bed boiler. A portion of the flue gas generated by the heat carrier heater is also introduced into the circulating fluidized bed boiler to burn together with the coke to generate steam for power generation. The flue gas after combustion is also sent to the dust collector for collection and dust removal.

[0025] As a preferred technical solution of this utility model, the gasification unit includes a third gas-solid separator and a gasifier. The fine coke outlet at the top of the classifier is connected to the inlet of the third gas-solid separator, the solid phase outlet of the third gas-solid separator is connected to the inlet of the gasifier, and the outlet gas phase of the third gas-solid separator is used for waste heat recovery.

[0026] The flue gas outlet of the circulating fluidized bed boiler is connected to the inlet of the third gas-solid separator.

[0027] As a preferred technical solution of this utility model, the third gas-solid separator includes any one of a dust collector with reverse airflow, a multi-cartridge dust collector, or a multi-cartridge dust collector with reverse airflow.

[0028] The gasifier is a dry powder gasifier, which is equipped with a coke inlet, an oxygen-containing gas inlet, a steam inlet, a syngas outlet, and an ash outlet.

[0029] In this invention, the fine coke powder classified by the classifier enters the dust collector together with the airflow for gas-solid separation. The flue gas after dust removal goes to the waste heat recovery unit to recover waste heat. The collected fine coke powder is discharged into the gasifier through the discharge valve and generates syngas through the gasification reaction, effectively utilizing the high-temperature energy in the coke powder and improving the energy utilization rate.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The device described in this utility model classifies the coke after pyrolysis of pulverized coal by particle size. The coke with smaller particle size is directly used for gasification, while the coke with larger particle size is used as fuel for circulating fluidized bed boilers. The above two utilization methods can meet the requirements of different devices for coke particle size, thereby effectively improving the utilization rate of coke and maximizing the utilization of the sensible heat of coke to achieve efficient recovery and utilization of system energy. At the same time, it reduces the pretreatment cost of downstream coke processing and truly realizes efficient graded and graded utilization of coke.

[0032] (2) The device described in this utility model has a reasonable structural design and makes clean and efficient use of coal, which helps to develop large-scale coal pyrolysis devices and creates conditions for the large-scale development of downstream industrial chains. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the integrated device for pulverized coal pyrolysis and circulating fluidized bed boiler and gasifier provided in Embodiment 1 of this utility model;

[0034] Among them, 1-pyrolysis reactor, 11-first gas-solid separator, 2-heat carrier heater, 21-second gas-solid separator, 3-flue gas generator, 4-air classifier, 5-coke buffer tank, 6-circulating fluidized bed boiler, 7-third gas-solid separator, 8-gasifier. Detailed Implementation

[0035] 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.

[0036] The following are typical but non-limiting embodiments of this utility model:

[0037] Example 1:

[0038] This embodiment provides an integrated device for pulverized coal pyrolysis, circulating fluidized bed boiler, and gasifier. A schematic diagram of the integrated device is shown below. Figure 1 As shown, it includes a pyrolysis unit, a heat carrier heating unit, a classifying unit, a circulating fluidized bed boiler unit, and a gasification unit. The solid phase outlet of the pyrolysis unit is independently connected to the inlet of the heat carrier heating unit and the inlet of the classifying unit. The flue gas outlet pipeline of the heat carrier heating unit is divided into two branches, which are respectively connected to the inlet of the classifying unit and the inlet of the circulating fluidized bed boiler unit. The upper outlet of the classifying unit is connected to the inlet of the gasification unit, and the lower outlet of the classifying unit is connected to the inlet of the circulating fluidized bed boiler unit.

[0039] The pyrolysis unit includes a pyrolysis reactor 1, and a first gas-solid separator 11 is provided in the upper part of the pyrolysis reactor 1; the first gas-solid separator 11 includes a first-stage cyclone separator.

[0040] The heat carrier heating unit includes a heat carrier heater 2 and a flue gas generator 3. The flue gas generator 3 is provided with a fuel inlet and an air inlet. The fuel inlet includes a fuel oil inlet and a fuel gas inlet. The outlet of the flue gas generator 3 is connected to the lower inlet of the heat carrier heater 2.

[0041] The first coke outlet of the pyrolysis reactor 1 is connected to the lower inlet of the heat carrier heater 2 via a heat carrier circulation pipe, and the bottom outlet of the heat carrier heater 2 is connected to the feed pipe of the pyrolysis reactor 1.

[0042] The upper part of the heat carrier heater 2 is provided with a second gas-solid separator 21, which includes a first-stage cyclone separator.

[0043] The powder classifier unit includes a powder classifier 4. The second coke outlet of the pyrolysis reactor 1 is connected to the inlet of the powder classifier 4. One of the flue gas outlet pipes of the heat carrier heater 2 is connected to the inlet pipe of the powder classifier 4 and enters the powder classifier 4 together with the coke.

[0044] The classifier 4 is equipped with a grading rotor to separate coke powder into fine coke powder and coarse coke powder. The fine coke powder has a particle size of less than 200μm, and the coarse coke powder has a particle size of more than 200μm.

[0045] The circulating fluidized bed boiler unit includes a coke buffer tank 5 and a circulating fluidized bed boiler 6. The coarse coke outlet at the bottom of the classifier 4 is connected to the inlet of the coke buffer tank 5, and the outlet of the coke buffer tank 5 is connected to the inlet of the circulating fluidized bed boiler 6.

[0046] The circulating fluidized bed boiler 6 is provided with a flue gas inlet, a deoxygenated water inlet, a steam outlet, a combustion flue gas outlet, and an ash outlet. Another flue gas outlet pipeline of the heat carrier heater 2 is connected to the lower flue gas inlet of the circulating fluidized bed boiler 6.

[0047] The gasification unit includes a third gas-solid separator 7 and a gasifier 8. The fine coke outlet at the top of the classifier 4 is connected to the inlet of the third gas-solid separator 7. The solid phase outlet of the third gas-solid separator 7 is connected to the inlet of the gasifier 8. The gas phase outlet of the third gas-solid separator 7 is used for waste heat recovery.

[0048] The flue gas outlet of the circulating fluidized bed boiler 6 is connected to the inlet of the third gas-solid separator 7.

[0049] The third gas-solid separator 7 is a multi-filter cartridge dust collector with backflushing, and its material is high-temperature resistant ceramic.

[0050] The gasifier 8 is a dry powder gasifier, and the gasifier 8 is equipped with a coke inlet, an oxygen inlet, a steam inlet, a syngas outlet, and an ash outlet.

[0051] Example 2:

[0052] This embodiment provides an integrated device for pulverized coal pyrolysis, circulating fluidized bed boiler, and gasifier. The integrated device includes a pyrolysis unit, a heat carrier heating unit, a pulverized coal classifier unit, a circulating fluidized bed boiler unit, and a gasification unit. The solid phase outlet of the pyrolysis unit is independently connected to the inlet of the heat carrier heating unit and the inlet of the pulverized coal classifier unit. The flue gas outlet pipeline of the heat carrier heating unit is divided into two branches, which are respectively connected to the inlet of the pulverized coal classifier unit and the inlet of the circulating fluidized bed boiler unit. The upper outlet of the pulverized coal classifier unit is connected to the inlet of the gasification unit, and the lower outlet of the pulverized coal classifier unit is connected to the inlet of the circulating fluidized bed boiler unit.

[0053] The pyrolysis unit includes a pyrolysis reactor 1, and a first gas-solid separator 11 is provided in the upper part of the pyrolysis reactor 1; the first gas-solid separator 11 includes a two-stage cyclone separator.

[0054] The heat carrier heating unit includes a heat carrier heater 2 and a flue gas generator 3. The flue gas generator 3 is provided with a fuel inlet and an air inlet. The fuel inlet includes a fuel oil inlet. The outlet of the flue gas generator 3 is connected to the lower inlet of the heat carrier heater 2.

[0055] The first coke outlet of the pyrolysis reactor 1 is connected to the lower inlet of the heat carrier heater 2 via a heat carrier circulation pipe, and the bottom outlet of the heat carrier heater 2 is connected to the feed pipe of the pyrolysis reactor 1.

[0056] The upper part of the heat carrier heater 2 is provided with a second gas-solid separator 21, which includes a two-stage cyclone separator.

[0057] The powder classifier unit includes a powder classifier 4. The second coke outlet of the pyrolysis reactor 1 is connected to the inlet of the powder classifier 4. One of the flue gas outlet pipes of the heat carrier heater 2 is connected to the inlet pipe of the powder classifier 4 and enters the powder classifier 4 together with the coke.

[0058] The classifier 4 is equipped with a grading rotor to separate coke powder into fine coke powder and coarse coke powder. The fine coke powder has a particle size of less than 180μm, and the coarse coke powder has a particle size of more than 180μm.

[0059] The circulating fluidized bed boiler unit includes a coke buffer tank 5 and a circulating fluidized bed boiler 6. The coarse coke outlet at the bottom of the classifier 4 is connected to the inlet of the coke buffer tank 5, and the outlet of the coke buffer tank 5 is connected to the inlet of the circulating fluidized bed boiler 6.

[0060] The circulating fluidized bed boiler 6 is provided with a flue gas inlet, a deoxygenated water inlet, a steam outlet, a combustion flue gas outlet, and an ash outlet. Another flue gas outlet pipeline of the heat carrier heater 2 is connected to the lower flue gas inlet of the circulating fluidized bed boiler 6.

[0061] The gasification unit includes a third gas-solid separator 7 and a gasifier 8. The fine coke outlet at the top of the classifier 4 is connected to the inlet of the third gas-solid separator 7. The solid phase outlet of the third gas-solid separator 7 is connected to the inlet of the gasifier 8. The gas phase outlet of the third gas-solid separator 7 is used for waste heat recovery.

[0062] The flue gas outlet of the circulating fluidized bed boiler 6 is connected to the inlet of the third gas-solid separator 7.

[0063] The third gas-solid separator 7 is a multi-filter cartridge dust collector with backflushing, and its material is high-temperature resistant carbonate fiber.

[0064] The gasifier 8 is a dry powder gasifier, and the gasifier 8 is equipped with a coke inlet, an oxygen inlet, a steam inlet, a syngas outlet, and an ash outlet.

[0065] Example 3:

[0066] This embodiment provides an integrated device for pulverized coal pyrolysis, circulating fluidized bed boiler, and gasifier. The integrated device includes a pyrolysis unit, a heat carrier heating unit, a pulverized coal classifier unit, a circulating fluidized bed boiler unit, and a gasification unit. The solid phase outlet of the pyrolysis unit is independently connected to the inlet of the heat carrier heating unit and the inlet of the pulverized coal classifier unit. The flue gas outlet pipeline of the heat carrier heating unit is divided into two branches, which are respectively connected to the inlet of the pulverized coal classifier unit and the inlet of the circulating fluidized bed boiler unit. The upper outlet of the pulverized coal classifier unit is connected to the inlet of the gasification unit, and the lower outlet of the pulverized coal classifier unit is connected to the inlet of the circulating fluidized bed boiler unit.

[0067] The pyrolysis unit includes a pyrolysis reactor 1, and a first gas-solid separator 11 is provided in the upper part of the pyrolysis reactor 1; the first gas-solid separator 11 includes a two-stage cyclone separator.

[0068] The heat carrier heating unit includes a heat carrier heater 2 and a flue gas generator 3. The flue gas generator 3 is provided with a fuel inlet and an air inlet. The fuel inlet includes a fuel gas inlet. The outlet of the flue gas generator 3 is connected to the lower inlet of the heat carrier heater 2.

[0069] The first coke outlet of the pyrolysis reactor 1 is connected to the lower inlet of the heat carrier heater 2 via a heat carrier circulation pipe, and the bottom outlet of the heat carrier heater 2 is connected to the feed pipe of the pyrolysis reactor 1.

[0070] The upper part of the heat carrier heater 2 is provided with a second gas-solid separator 21, which includes a two-stage cyclone separator.

[0071] The powder classifier unit includes a powder classifier 4. The second coke outlet of the pyrolysis reactor 1 is connected to the inlet of the powder classifier 4. One of the flue gas outlet pipes of the heat carrier heater 2 is connected to the inlet pipe of the powder classifier 4 and enters the powder classifier 4 together with the coke.

[0072] The powder classifier 4 is equipped with a filter screen inside to separate coke powder into fine coke powder and coarse coke powder. The fine coke powder has a particle size of less than 220μm, and the coarse coke powder has a particle size of more than 220μm.

[0073] The circulating fluidized bed boiler unit includes a circulating fluidized bed boiler 6, and the coarse coke outlet at the bottom of the classifier 4 is connected to the inlet of the circulating fluidized bed boiler 6.

[0074] The circulating fluidized bed boiler 6 is provided with a flue gas inlet, a deoxygenated water inlet, a steam outlet, a combustion flue gas outlet, and an ash outlet. Another flue gas outlet pipeline of the heat carrier heater 2 is connected to the lower flue gas inlet of the circulating fluidized bed boiler 6.

[0075] The gasification unit includes a third gas-solid separator 7 and a gasifier 8. The fine coke outlet at the top of the classifier 4 is connected to the inlet of the third gas-solid separator 7. The solid phase outlet of the third gas-solid separator 7 is connected to the inlet of the gasifier 8. The gas phase outlet of the third gas-solid separator 7 is used for waste heat recovery.

[0076] The flue gas outlet of the circulating fluidized bed boiler 6 is connected to the inlet of the third gas-solid separator 7.

[0077] The third gas-solid separator 7 is equipped with a reverse-blowing dust collector and is made of high-temperature resistant ceramic material.

[0078] The gasifier 8 is a dry powder gasifier, and the gasifier 8 is provided with a coke inlet, an air inlet, a steam inlet, a syngas outlet, and an ash outlet.

[0079] The integrated treatment method of pulverized coal pyrolysis and circulating fluidized bed boiler and gasifier using the apparatus in Example 1 above includes the following steps:

[0080] Pulverized coal with a particle size of less than 1 mm is rapidly mixed with circulating coal gas and a heat carrier and then fed into a pyrolysis reactor. The reaction temperature is 500-550℃. The reaction produces oil and gas and pulverized coke. The oil and gas are separated into gas and solid by a cyclone separator at the top of the pyrolysis reactor. The oil and gas are sent to a downstream unit for oil and gas separation. Part of the pulverized coke is fed into the heat carrier heater through a heat carrier circulation pipe. It is then burned with the flue gas generated by the flue gas generator in a low-oxygen environment to heat the pulverized coke in the heat carrier heater. The heated pulverized coke is mixed with pulverized coal and circulating coal gas under gravity and serves as the heat source for the pyrolysis reaction. Part of the flue gas from the outlet heated by the heat carrier is used as the lifting flue gas for the air classifier, and the other part is sent to a circulating fluidized bed boiler for combustion and power generation.

[0081] Another portion of the pyrolysis coke enters the classifier of the classifier unit from the bottom of the pyrolysis reactor. The coke is then classified in the classification zone after being lifted by the flue gas from the heat carrier heater. Fine coke particles smaller than 200μm enter the dust collector along with the airflow for dust removal. The flue gas after dust removal goes to the waste heat recovery unit to recover waste heat. The collected fine coke particles are fed into the gasifier to undergo gasification reaction to produce syngas. Coarse coke particles larger than 200μm are discharged to the coke buffer tank by gravity through the classifier and then directly transported to the furnace of the circulating fluidized bed boiler for combustion to produce steam for power generation. The high-temperature flue gas after combustion is sent to the dust collector for dust removal.

[0082] As can be seen from the above embodiments, the device of this utility model classifies the coke after pulverized coal pyrolysis by particle size. The smaller coke particles are directly used for gasification, while the larger coke particles are used as fuel for circulating fluidized bed boilers. These two utilization methods can meet the particle size requirements of different devices, thereby effectively improving the utilization rate of coke and maximizing the use of the sensible heat of coke to achieve efficient energy recovery and utilization of the system. At the same time, it reduces the pretreatment cost of downstream coke processing and truly realizes efficient graded and quality-based utilization of coke. The device has a reasonable structural design, and the coal utilization is clean and efficient, which is conducive to the large-scale development of pulverized coal pyrolysis devices and creates conditions for the large-scale development of downstream industrial chains.

[0083] 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. An integrated device of pulverized coal pyrolysis and circulating fluidized bed boiler, gasifier, characterized in that, The integrated device comprises a pyrolysis unit, a heat carrier heating unit, a powder selection unit, a circulating fluidized bed boiler unit and a gasification unit, a solid phase outlet of the pyrolysis unit is independently connected with an inlet of the heat carrier heating unit and an inlet of the powder selection unit, a flue gas outlet pipeline of the heat carrier heating unit is divided into two branches and is connected with the inlet of the powder selection unit and the inlet of the circulating fluidized bed boiler unit respectively, an upper outlet of the powder selection unit is connected with an inlet of the gasification unit, and a lower outlet of the powder selection unit is connected with an inlet of the circulating fluidized bed boiler unit.

2. The apparatus according to claim 1, wherein the apparatus is characterized by: The pyrolysis unit comprises a pyrolysis reactor, and a first gas-solid separator is arranged at an upper portion in the pyrolysis reactor. The first gas-solid separator comprises at least one cyclone separator.

3. The apparatus according to claim 1, wherein the apparatus is characterized by: The heat carrier heating unit comprises a heat carrier heater and a flue gas generator, a fuel inlet and an air inlet are arranged on the flue gas generator, and an outlet of the flue gas generator is connected with a lower inlet of the heat carrier heater. A first powder coke outlet of the pyrolysis unit is connected with the lower inlet of the heat carrier heater through a heat carrier circulation pipe, and a bottom outlet of the heat carrier heater is connected to a feeding pipeline of the pyrolysis unit.

4. The apparatus according to claim 3, wherein the apparatus is characterized by: A second gas-solid separator is arranged at an upper portion in the heat carrier heater, and the second gas-solid separator comprises at least one cyclone separator.

5. The apparatus according to claim 3, wherein the apparatus is characterized by: The powder selection unit comprises a powder selection machine, a second powder coke outlet of the pyrolysis unit is connected with an inlet of the powder selection machine, and one of flue gas outlet pipelines of the heat carrier heater is connected to an inlet pipeline of the powder selection machine to enter the powder selection machine together with the powder coke.

6. The apparatus according to claim 5, wherein the apparatus is characterized by: An internal portion of the powder selection machine is provided with a grading rotor or a filter screen to divide the powder coke into fine powder coke and coarse powder coke, a particle size of the fine powder coke is below 180-220 μm, and a particle size of the coarse powder coke is above 180-220 μm.

7. The apparatus according to claim 6, wherein the apparatus is characterized by: The circulating fluidized bed boiler unit comprises a powder coke buffer tank and a circulating fluidized bed boiler, a coarse powder coke outlet at a lower portion of the powder selection machine is connected with an inlet of the powder coke buffer tank, and an outlet of the powder coke buffer tank is connected with an inlet of the circulating fluidized bed boiler.

8. The apparatus according to claim 7, wherein the apparatus is characterized by: The circulating fluidized bed boiler is provided with a flue gas inlet, an oxygen-removing water inlet, a steam outlet, a combustion flue gas outlet and an ash outlet, and the other flue gas outlet pipeline of the heat carrier heater is connected with a lower flue gas inlet of the circulating fluidized bed boiler.

9. The apparatus according to claim 8, wherein the apparatus is characterized by: The gasification unit comprises a third gas-solid separator and a gasification furnace, a fine powder coke outlet at an upper portion of the powder selection machine is connected with an inlet of the third gas-solid separator, a solid phase outlet of the third gas-solid separator is connected with an inlet of the gasification furnace, and a gas phase outlet of the third gas-solid separator is provided with a waste heat recovery device. A combustion flue gas outlet of the circulating fluidized bed boiler is connected with an inlet of the third gas-solid separator.

10. The apparatus according to claim 9, wherein the apparatus is characterized by: The third gas-solid separator comprises any one of a back-blowing dust collector, a multi-filter-cylinder dust collector or a multi-filter-cylinder dust collector with back-blowing. The gasification furnace is a dry powder gasification furnace, and the gasification furnace is provided with a powder coke inlet, an oxygen-containing gas inlet, a steam inlet, a synthesis gas outlet and an ash outlet.

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