A synergistic coupling system and process for coal pyrolysis quality separation and multi-generation

Abstract

The present invention belongs to the field of coal chemical industry and discloses a synergistic coupling system and process for coal pyrolysis, quality separation and multi-generation. The coupling system includes a clean coal storage bin, a coal slime storage bin, a pyrolysis and separation system and a coal-fired power generation system. The pyrolysis and separation system includes a pyrolysis device, a semi-coke separation device, and a desorption gas separation device. The coal-fired power generation system includes a boiler, which is respectively connected to the semi-coke separation device, the desorption gas separation device and the coal slime storage bin so that the semi-coke, desorption gas and coal slime can be burned in the boiler to generate electricity. The process includes first washing the raw coal to obtain clean coal and coal slime; then pyrolyzing the clean coal, separating the pyrolysis products to obtain semi-coke and pyrolysis gas, removing hydrogen from the pyrolysis gas to obtain desorption gas; and finally, sending the semi-coke, coal slime and desorption gas into the boiler for combustion to generate electricity. The present invention couples pyrolysis and power generation, which not only improves the combustion efficiency of semi-coke, but also increases the value of resource utilization.

Description

Technical Field

[0001] The present invention relates to the technical field of coal chemical industry, and in particular to a synergistic coupling system and process for coal pyrolysis, quality separation and polygeneration. Background Art

[0002] my country is rich in coal resources, and the rational utilization of these resources is a key link in the coal industry chain. Coal pyrolysis technology is a key approach to the efficient and clean utilization of coal resources. The products produced by pyrolysis, such as semi-coke, coal tar, and desorbed gas, can be used in different fields, achieving the differentiated utilization of coal.

[0003] Currently, there are technologies that can use semi-coke produced by coal pyrolysis for co-firing and power generation, achieving a coupling between the coal pyrolysis and power industries. However, due to the low volatile content of semi-coke and incomplete combustion, there are still problems with insufficient combustion efficiency and power generation efficiency. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a coal pyrolysis quality separation and polygeneration synergistic coupling system and process.

[0005] According to one aspect of the present invention, a coal pyrolysis quality separation and polygeneration synergistic coupling system is provided, comprising:

[0006] Clean coal storage silos, coal slime storage silos, pyrolysis and separation systems, and coal-fired power generation systems;

[0007] The pyrolysis and separation system includes a pyrolysis device for pyrolyzing the clean coal transported from the clean coal storage bin to produce pyrolysis products, a semi-coke separation device for separating semi-coke from the pyrolysis products to obtain semi-coke, a pyrolysis gas separation device for separating pyrolysis gas from the pyrolysis products to obtain pyrolysis gas products, and a desorption gas separation device for separating hydrogen from the pyrolysis gas products to form desorption gas.

[0008] The coal-fired power generation system includes a boiler, which includes a semi-coke inlet for connecting to the semi-coke separation device, a desorption gas inlet for connecting to the desorption gas separation device, and a coal slime inlet for connecting to the coal slime storage bin. The boiler is used to burn the semi-coke, desorption gas and coal slime together to generate electricity.

[0009] According to an exemplary embodiment of the present invention, the boiler comprises a pulverized coal boiler and / or a fluidized bed boiler.

[0010] According to an exemplary embodiment of the present invention, when the boiler includes both a pulverized coal boiler and a fluidized bed boiler, the coupling system further includes a screening device, which is connected between the semi-coke separation device and the boiler and is used to screen the separated semi-coke into different particle sizes, so that semi-coke of a certain particle size enters the pulverized coal boiler and semi-coke of another particle size enters the fluidized bed boiler.

[0011] According to an exemplary embodiment of the present invention, when the boiler only includes the pulverized coal furnace, the clean coal storage bin is connected to a clean coal pulverizing device, which is used to prepare the clean coal into pulverized coal so as to pyrolyze the pulverized coal into pulverized coke; the coal slime storage bin is connected to a coal slime pulverizing device, which is used to prepare the coal slime into coal slime powder.

[0012] According to an exemplary embodiment of the present invention, the semi-coke outlet of the semi-coke separation device is connected to the semi-coke inlet of the boiler via a semi-coke conveying pipe, the desorbed gas outlet of the desorbed gas separation device is connected to the desorbed gas inlet of the boiler via a desorbed gas conveying pipe, and the pulverized coal slime outlet of the pulverized coal slime device is connected to the pulverized coal slime inlet of the boiler via a pulverized coal slime conveying pipe;

[0013] The desorption gas conveying pipeline is connected to the semi-coke conveying pipeline so that the desorption gas blows the separated coke powder into the boiler, and / or the desorption gas conveying pipeline is connected to the coal slime conveying pipeline so that the desorption gas blows the crushed coal slime powder into the boiler.

[0014] According to an exemplary embodiment of the present invention, the coupling system further includes a hot flue gas delivery pipe and a heat exchanger. The hot flue gas delivery pipe is connected to the flue gas outlet of the boiler and is used to deliver the hot flue gas generated by combustion in the boiler to the outside; the hot flue gas delivery pipe and the desorbed gas delivery pipe are both connected to the heat exchanger to transfer the heat of the hot flue gas to the desorbed gas through the heat exchanger.

[0015] According to an exemplary embodiment of the present invention, the coal slime storage bin is connected to a drying device, and the drying device is used to dry the coal slime;

[0016] The coupling system further includes a hot flue gas conveying pipeline, which is connected to the flue gas outlet of the boiler and is used to convey the hot flue gas generated by the combustion of the boiler to the outside; the hot flue gas conveying pipeline is connected to the drying device to use the hot flue gas to dry the coal slime.

[0017] According to another aspect of the present invention, a synergistic coupling process for coal pyrolysis, quality separation and polygeneration is provided, comprising:

[0018] Washing of raw coal produces clean coal and coal slime;

[0019] The clean coal is pyrolyzed, and the pyrolysis products are separated to obtain semi-coke and pyrolysis gas, and hydrogen in the pyrolysis gas is removed to obtain desorbed gas;

[0020] The semi-coke, coal slime and desorbed gas are fed into the boiler for combustion to generate electricity.

[0021] According to an exemplary embodiment of the present invention, the boiler comprises a pulverized coal boiler and / or a fluidized bed boiler; when the boiler comprises a pulverized coal boiler, the process further comprises:

[0022] pulverizing the coal slime to obtain coal slime powder;

[0023] Pulverizing the clean coal and obtaining fine coke after pyrolysis;

[0024] The desorbed gas is used to blow the coal sludge powder and / or fine coke into the boiler for combustion.

[0025] According to an exemplary embodiment of the present invention, the process further comprises:

[0026] collecting hot flue gas generated by boiler combustion, and transferring the heat of the hot flue gas to the desorbed gas using a heat exchanger to preheat the desorbed gas;

[0027] And / or, hot flue gas generated by boiler combustion is collected and used to dry the washed coal slime.

[0028] The present invention efficiently couples the modern coal chemical industry coal fractionation pyrolysis process with traditional coal-fired power generation technology. It uses pyrolysis byproduct semi-coke, desorbed gas after hydrogen extraction from pyrolysis gas without conversion, and solid waste coal slime after raw coal screening as raw materials to replace fuel coal as energy supply raw materials for combustion and power generation. Its beneficial effects are mainly in the following aspects:

[0029] (1) Semi-coke is the main energy source. Its high calorific value, low ash and low sulfur characteristics make it more environmentally friendly and economical when burned in power plant boilers. (2) The methane, carbon monoxide, hydrocarbon gases and other highly active components in the desorbed gas can effectively compensate for the problem of poor combustion performance compared with raw coal, delayed combustion and reduced combustion efficiency caused by the low volatile matter of semi-coke. It can also be used as a conveying gas for semi-coke. (3) Coal slime is a solid waste. It is mixed with semi-coke and used for combustion power generation, realizing the resource utilization of waste.

[0030] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are incorporated into and constitute a part of this specification, illustrate embodiments consistent with the present invention, and together with the description, serve to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and it is clear that those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0032] Figure 1 It is the first coal pyrolysis quality separation and multi-generation synergistic coupling system;

[0033] Figure 2 It is the second type of coal pyrolysis quality separation and multi-generation synergistic coupling system;

[0034] Figure 3 It is the third type of coal pyrolysis quality separation and multi-generation synergistic coupling system.

[0035] In the figure: 1. Clean coal storage silo; 11. Clean coal drying device; 12. Clean coal pulverizing device; 2. Coal slime storage silo; 20. Coal slime conveying pipeline; 21. Coal slime drying device; 22. Coal slime pulverizing device; 23. Coal slime screening device; 3. Pyrolysis device; 41. Semi-coke separation device; 42. Pyrolysis gas separation device; 43. Desorption gas separation device; 44. Semi-coke screening equipment; 410. Semi-coke conveying pipeline; 430. Desorption gas conveying pipeline; 5. Boiler; 50. Hot flue gas conveying pipeline; 51. Fluidized bed boiler; 52. Pulverized coal furnace; 7. Heat exchanger. DETAILED DESCRIPTION

[0036] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. Like reference numerals in the figures represent identical or similar structures, and thus their detailed description will be omitted. Furthermore, the figures are merely schematic illustrations of the present invention and are not necessarily drawn to scale.

[0037] Although relative terms such as "upper" and "lower" are used in this specification to describe the relationship of one illustrated component to another, these terms are used herein for convenience only, such as in accordance with the orientation of the illustrations in the accompanying drawings. It will be understood that if the illustrated device were flipped upside down, the component described as "upper" would become the component "lower." When a structure is referred to as "on" another structure, this may mean that the structure is integrally formed with the other structure, that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure via the other structure.

[0038] The terms "a", "an", "the", "said" and "at least one" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express open-ended inclusion and mean that additional elements / components / etc. may be present in addition to the listed elements / components / etc.; the terms "first", "second" and "third" etc. are used only as labels and are not intended to limit the quantity of their objects.

[0039] The embodiment of the present invention discloses a coal pyrolysis quality separation and multi-generation synergistic coupling system, referring to Figure 1-Figure 3 , comprising a clean coal storage bin 1, a coal slime storage bin 2, a pyrolysis and separation system, and a coal-fired power generation system. Clean coal and coal slime are the two main products obtained after raw coal is washed. The clean coal storage bin 1 is used to store clean coal, and the coal slime storage bin 2 is used to store coal slime. The pyrolysis and separation system comprises a pyrolysis device 3 for pyrolyzing the clean coal transported from the clean coal storage bin 2 to produce pyrolysis products, a semi-coke separation device 41 for separating semi-coke from the pyrolysis products to obtain semi-coke, a pyrolysis gas separation device 42 for separating pyrolysis gas from the pyrolysis products to obtain pyrolysis gas products, and a desorption gas separation device 43 for separating hydrogen from the pyrolysis gas products to form desorption gas. The coal-fired power generation system comprises a boiler 5, which includes a semi-coke inlet for connecting to the semi-coke separation device 41, a desorption gas inlet for connecting to the desorption gas separation device 43, and a coal slime inlet for connecting to the coal slime storage bin 2. The boiler 5 is used to combust the semi-coke, desorption gas, and coal slime together to generate electricity.

[0040] In this implementation, semi-coke serves as the primary energy source. Its high calorific value, low ash content, and low sulfur content improve environmental performance and economic efficiency when used in power plant boilers. The highly reactive components in the desorbed gas, such as methane, carbon monoxide, and hydrocarbons, effectively compensate for the lower combustion performance, delayed combustion, and reduced efficiency associated with semi-coke's low volatile content compared to raw coal. Furthermore, coal slime, a solid waste, is blended with semi-coke and then used for combustion in power generation, achieving waste resource utilization.

[0041] The coal pyrolysis quality separation and polygeneration synergistic coupling system of this embodiment is further described in detail below.

[0042] In the present invention, clean coal refers to the coal that can be used for pyrolysis, gasification, and combustion to generate electricity after the gangue and coal slime are removed after washing. The coal pyrolysis described in the present invention refers to the thermal conversion process in which coal is heated in a non-oxidizing atmosphere in the pyrolysis device 3 to undergo physical and chemical reactions to form solid, gaseous, and liquid products, which is a key step in the thermal conversion of coal. The raw coal for the coal pyrolysis of the present invention is any type of coal that can be pyrolyzed to produce semi-coke, such as lignite, long flame coal, non-sticky coal, weakly sticky coal, etc. Its solid product is semi-coke generated by coal pyrolysis under low temperature conditions (such as 500-900°C), the gaseous product is pyrolysis gas mainly composed of hydrogen, carbon dioxide, methane, carbon monoxide, nitrogen and other gases, and the liquid is coal tar mainly composed of chain hydrocarbons and aromatic hydrocarbons.

[0043] The pyrolysis and separation system includes a pyrolysis unit 3, a semi-coke separation unit 41, a pyrolysis gas separation unit 42, and a desorption gas separation unit 43. The pyrolysis unit 3 provides a site for the coal pyrolysis reaction. The pyrolysis unit 3 can utilize any commonly used pyrolysis technology, such as entrained-flow pyrolysis, fluidized-bed pyrolysis, or fixed-bed pyrolysis. After the pyrolysis reaction is complete, the pyrolysis products, in solid, liquid, and gaseous forms, are discharged from the material outlet and fed into subsequent separation equipment.

[0044] The semi-coke separation device 41 is used to separate the solid semi-coke from the pyrolysis products. Generally speaking, due to the high temperature of coal pyrolysis, the coal tar generated by pyrolysis initially mixes with the pyrolysis gas in a vaporous state. That is, the remaining material after the semi-coke is removed is a gas-liquid mixture. The semi-coke separation device 41 can be any device capable of separating the semi-coke from the pyrolysis products. In some specific embodiments, the semi-coke separation device 41 is a cyclone separator.

[0045] The pyrolysis gas separation device 42 is used to separate coal tar from the gas-liquid mixture to produce pure pyrolysis gas. Pyrolysis gas typically includes various gases such as hydrogen, methane, carbon dioxide, carbon monoxide, and nitrogen. The pyrolysis gas separation device 42 can be any device capable of separating coal tar from the gas phase. In some embodiments, the pyrolysis gas separation device 42 employs a condenser or a filter bed.

[0046] The desorbed gas separation device 43 is used to separate the hydrogen in the pyrolysis gas product to obtain desorbed gas. The hydrogen in the pyrolysis gas can be used as the main component of synthesis gas for the preparation of chemicals, and can also be used to hydrogenate coal tar to produce oil products. Therefore, the hydrogen is separated out separately, and the remaining desorbed gas contains methane, carbon dioxide, carbon monoxide, nitrogen and other gases. These gases can be used as fuel to improve the combustion efficiency of semi-coke and coal slime. The desorbed gas separation device 43 can be any device that can separate hydrogen. In some embodiments, the desorbed gas separation device 43 adopts a pressure swing adsorption device.

[0047] Coal-fired power generation systems typically consist of a combustion system and an electrical system. The combustion system, centered around a boiler, burns coal or coke to generate heat, which is then transferred to water to generate high-temperature, high-pressure steam. The electrical system converts the steam's thermal and mechanical energy into electrical energy.

[0048] In this embodiment of the present invention, the boiler 5 includes a semi-coke inlet, a desorbed gas inlet, and a coal slime inlet. The semi-coke inlet of the boiler is connected to the semi-coke separation device 41. The semi-coke separated by the semi-coke separation device 41 enters the boiler 5 through the semi-coke inlet. The desorbed gas inlet is connected to the desorbed gas separation device 43. The desorbed gas separated by the desorbed gas separation device 43 enters the boiler 5 through the desorbed gas inlet. The coal slime inlet is connected to the coal slime storage silo 2. The coal slime inlet enters the boiler 5 through the coal slime inlet.

[0049] It should be noted that the semi-coke inlet, the desorption gas inlet and the coal slime inlet can be different inlets or the same inlet, and the present invention does not specifically limit this.

[0050] The boiler 5 of the present invention may include a pulverized coal boiler 52 and / or a fluidized bed boiler 51 , that is, it may include a pulverized coal boiler 52 , may include a fluidized bed boiler 51 , or may include both boilers.

[0051] refer to Figure 1 In a specific example, the boiler 5 is a pulverized coal furnace. Since the pulverized coal furnace 52 requires the particle size of the fuel to be in the micron level, the semi-coke and coal slime entering the boiler should be in the micron level. Therefore, in this embodiment, the clean coal storage bin 1 is connected to a clean coal pulverizing device 12, which is used to prepare the clean coal into micron-level pulverized coal, and the pulverized coal is pyrolyzed into pulverized coke to meet the requirements of the pulverized coal furnace. In this embodiment, the coal slime storage bin 2 is connected to a coal slime pulverizing device 22, which is used to prepare the coal slime into coal slime powder to meet the requirements of the pulverized coal furnace. The co-firing of powdered semi-coke and coal slime has a large contact area with the air, more complete combustion, and reduces solid waste such as ash and residual carbon. As Figure 1 As shown, in this embodiment, the fine coke and the fine coal slime can be blown into the boiler 5 from the same inlet by the conveying gas, that is, the semi-coke inlet and the coal slime inlet are the same inlet.

[0052] In this embodiment, desorption gas is used to blow the fine coke and coal slime into the boiler 5. Figure 1As shown, the semi-coke outlet of the semi-coke separation device 41 is connected to the semi-coke inlet of the boiler 5 via a semi-coke conveying pipe 410. The desorbed gas outlet of the desorbed gas separation device 43 is connected to the desorbed gas inlet of the boiler 5 via a desorbed gas conveying pipe 430. The pulverized coal slime outlet of the coal slime pulverizing device 22 is connected to the coal slime inlet of the boiler 5 via a coal slime conveying pipe 20. The desorbed gas conveying pipe 430 is connected to the semi-coke conveying pipe 410, and further connected to the coal slime conveying pipe 20, so that the desorbed gas can blow fine coke and fine coal slime into the boiler 5. Using the desorbed gas as the conveying gas for fine coke and fine coal slime can save conveying gas and fully utilize the desorbed gas.

[0053] Furthermore, the fine coke and coal slime powder can be fully mixed in a mixer before being blown into the boiler 5, and then enter the boiler 5, thereby allowing the fine coke, coal slime powder and desorbed gas to be fully mixed in advance, making the combustion more complete.

[0054] Continue to refer Figure 1 In this embodiment, the coupled system further includes a hot flue gas delivery pipe 50 and a heat exchanger 7. The hot flue gas delivery pipe 50 is connected to the flue gas outlet of the boiler 5 and is used to transport the hot flue gas generated by combustion in the boiler 5 to the outside. The hot flue gas delivery pipe 50 and the desorbed gas delivery pipe 430 are both connected to the heat exchanger 7. The heat exchanger 7 transfers heat from the hot flue gas to the desorbed gas, preheating the desorbed gas in advance. The desorbed gas can also be used to preheat fine coke and coal slime, thereby reducing boiler energy consumption. At the same time, the waste heat of the hot flue gas is fully utilized, reducing heat waste.

[0055] In addition, hot flue gas preheating can be used to dry the coal slime and clean coal. As shown in the figure, a coal slime drying device 21 is provided between the coal slime storage bin 2 and the pulverizing device for drying the coal slime. Specifically, a hot flue gas conveying conduit 50 is connected to the coal slime drying device 21 to utilize hot flue gas to dry the coal slime. A clean coal drying device 11 is also provided between the clean coal storage bin 1 and the clean coal pulverizing device 12 for drying the clean coal. Specifically, a hot flue gas conveying conduit 50 is connected to the clean coal drying device 11 to utilize hot flue gas to dry the clean coal.

[0056] refer to Figure 2 In another specific embodiment, boiler 5 is a fluidized bed boiler. The particle size of the fuel entering a fluidized bed boiler can be millimeter-sized, so the coal slime can be fed directly into the furnace without pulverizing. Pyrolysis utilizes granular coal with millimeter-sized particle sizes, producing millimeter-sized semi-coke, which can also be fed directly into the furnace. In this embodiment, the semi-coke and coal slime can be fed into the boiler via a screw feeder. Similar to the previous embodiment, the hot flue gas conveying conduit 50 can also be connected to the clean coal drying device 11 and the coal slime drying device 21, respectively, to dry the clean coal and coal slime using the hot flue gas.

[0057] refer to Figure 3In another specific embodiment, the boiler 5 includes a pulverized coal furnace 52 and a fluidized bed boiler 51. A slurry screening device 44 is further provided between the slurry separation device 41 and the boiler. This slurry screening device 44 is used to screen the slurry according to particle size, and then deliver slurry of different particle sizes to different boilers via different slurry delivery pipes 410. For example, micron-sized slurry is delivered to the pulverized coal furnace 52, and millimeter-sized slurry is delivered to the fluidized bed boiler 51, thereby achieving full combustion and utilization of slurry of different particle sizes. Similarly, a slurry screening device is further provided between the coal slurry storage bin 2 and the boiler. This slurry screening device is used to screen the slurry according to particle size, and then deliver slurry of different particle sizes to different boilers via different slurry delivery pipes 20. For example, micron-sized slurry is delivered to the pulverized coal furnace 52, and millimeter-sized slurry is delivered to the fluidized bed boiler 51, thereby achieving full combustion and utilization of slurry of different particle sizes. Through this hierarchical system, the coupling of two combustion power generation systems is achieved.

[0058] Continue to refer Figure 3 Similar to the previous embodiment, in this hierarchical coupling system, micron-sized semi-coke and coal slime can also be blown into the furnace for combustion via desorbed gas. Furthermore, heat from the hot flue gas can be transferred to the desorbed gas via heat exchanger 7, preheating the desorbed gas, semi-coke, and coal slime. Furthermore, the hot flue gas delivery pipeline 50 can also be connected to the clean coal drying device 11 and the coal slime drying device 21, respectively, to dry the clean coal and coal slime using the hot flue gas.

[0059] The embodiment of the present invention further discloses a synergistic coupling process for coal pyrolysis, quality separation and polygeneration, including:

[0060] Step S100, washing the raw coal to obtain clean coal and coal slime;

[0061] Step S200, pyrolyzing the clean coal, separating the pyrolysis products to obtain semi-coke and pyrolysis gas, and removing hydrogen from the pyrolysis gas to obtain desorbed gas;

[0062] In step S300, the semi-coke, coal slime and desorbed gas are fed into a boiler for combustion to generate electricity.

[0063] The coal pyrolysis quality separation and polygeneration synergistic coupling process of this embodiment is further described in detail below.

[0064] Washing in step S100 is the process of removing gangue and other impurities from coal. This process typically utilizes the differences in physical properties between coal, gangue, and coal slime, separating them in media of varying densities or properties. The clean coal and coal slime obtained from washing are typically dried in a drying device before further use.

[0065] In the above step S200, the clean coal is first fed into the pyrolysis device 3 for coal pyrolysis. After the pyrolysis reaction is completed, the pyrolysis products in the form of solid, liquid and gas enter the subsequent separation device. First, the solid phase semi-coke is separated from the pyrolysis products by the semi-coke separation device 41. Secondly, the coal tar is separated from the gas-liquid mixture by the pyrolysis gas separation device 42 to obtain pure pyrolysis gas. Finally, the hydrogen in the pyrolysis gas product is separated by the desorption gas separation device 43 to obtain desorption gas. The desorption gas contains methane, carbon dioxide, carbon monoxide, nitrogen and other gases. These gases can be used as fuel to improve the combustion efficiency of semi-coke and coal slime.

[0066] In step S300, the combustion of semi-coke, coal slime, and desorbed gas into the boiler to generate electricity is based on the principle that the fuel burns in the boiler, heating water to form steam. The steam pressure drives the turbine, which in turn drives the generator, converting mechanical energy into electrical energy. A combustion power generation system typically consists of a combustion system and an electrical system. The combustion system, with the boiler at its core, transfers the heat generated by coal or semi-coke combustion to water, generating high-temperature, high-pressure steam. The electrical system converts the thermal and mechanical energy of the steam into electrical energy.

[0067] When the combustion system uses different types of boilers, they correspond to different processes.

[0068] In one specific embodiment, boiler 5 utilizes a pulverized coal furnace. Because pulverized coal furnaces require a micron-sized fuel particle size, the clean coal must first be pulverized to the micron level to produce micron-sized fine coke after pyrolysis. Similarly, the coal sludge must also be pulverized to the micron level before being fed into the boiler via a conveying gas. Furthermore, desorbed gas can be used instead of conveying gas, directly blowing the coal sludge and fine coke into the boiler using the desorbed gas.

[0069] In another specific embodiment, the boiler 5 is a fluidized bed boiler. Since the fluidized bed boiler requires the fuel particle size to be in the millimeter level, there is no need to pulverize the coal slurry. In this embodiment, the semi-coke and coal slurry can be fed into the boiler via a screw feeder.

[0070] In another specific embodiment, the processes of the two aforementioned embodiments are coupled, namely, both a pulverized coal furnace 52 and a fluidized bed boiler 51 are included. Specifically, the semi-coke after pyrolysis is screened, and semi-coke with larger particle sizes (e.g., millimeter-level) is fed into the fluidized bed boiler 51 via a screw feeder, while coke fines with smaller particle sizes (e.g., micron-level) are blown into the pulverized coal furnace 52 via desorption gas. Similarly, the dried coal slime is screened, and coal slime with larger particle sizes (e.g., millimeter-level) is fed into the fluidized bed boiler 51 via a screw feeder, while coal slime with smaller particle sizes (e.g., micron-level) is blown into the pulverized coal furnace 52 via desorption gas.

[0071] In the above step S300, a large amount of high-temperature flue gas is generated during the combustion process of the boiler 5. This embodiment makes full use of the heat of the high-temperature flue gas.

[0072] In one specific embodiment, hot flue gas generated by boiler combustion is collected and heat is transferred from the hot flue gas to the desorbed gas via heat exchanger 7 to preheat the desorbed gas. When the desorbed gas is also used to blow fine coke and coal slime into the boiler, it can also preheat the fine coke and coal slime to increase the fuel entry temperature. In another specific embodiment, hot flue gas generated by boiler combustion is collected and used to dry the washed coal slime. Of course, the hot flue gas can be divided into two paths: one for preheating the desorbed gas and the other for drying the coal slime.

[0073] The specific process of the above process can be referred to the description of the coupling system above, which will not be repeated here. It should be noted that the step numbers of the present invention are used only for convenience of description and do not limit the order of the steps.

[0074] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the invention being indicated by the appended claims.

Claims

1. A coal pyrolysis quality separation and multi-generation synergistic coupling system, characterized in that: include: Clean coal storage silos, coal slime storage silos, pyrolysis and separation systems, and coal-fired power generation systems; The pyrolysis and separation system includes a pyrolysis device for pyrolyzing the clean coal transported from the clean coal storage bin to produce pyrolysis products, a semi-coke separation device for separating semi-coke from the pyrolysis products to obtain semi-coke, a pyrolysis gas separation device for separating pyrolysis gas from the pyrolysis products to obtain pyrolysis gas products, and a desorption gas separation device for separating hydrogen from the pyrolysis gas products to form desorption gas. The coal-fired power generation system includes a boiler, the boiler including a semi-coke inlet for connecting to the semi-coke separation device, a desorbed gas inlet for connecting to the desorbed gas separation device, and a coal slime inlet for connecting to the coal slime storage bin, and the boiler is used to combust the semi-coke, desorbed gas, and coal slime to generate electricity; The boiler comprises a pulverized coal boiler and / or a fluidized bed boiler; When the boiler comprises both a pulverized coal boiler and a fluidized bed boiler, the coupling system further comprises a screening device, the screening device being connected between the semi-coke separation device and the boiler and being used to screen the separated semi-coke into different particle sizes, so that semi-coke of a certain particle size enters the pulverized coal boiler and semi-coke of another particle size enters the fluidized bed boiler; When the boiler only includes the pulverized coal furnace, the clean coal storage bin is connected to a clean coal pulverizing device, which is used to prepare the clean coal into pulverized coal so as to pyrolyze the pulverized coal into pulverized coke; the coal slime storage bin is connected to a coal slime pulverizing device, which is used to prepare the coal slime into coal slime powder.

2. The coal pyrolysis quality separation and polygeneration synergistic coupling system according to claim 1 is characterized in that: The semi-coke outlet of the semi-coke separation device is connected to the semi-coke inlet of the boiler via a semi-coke conveying pipeline, the desorbed gas outlet of the desorbed gas separation device is connected to the desorbed gas inlet of the boiler via a desorbed gas conveying pipeline, and the coal slime outlet of the coal slime pulverizing device is connected to the coal slime inlet of the boiler via a coal slime conveying pipeline; The desorption gas conveying pipeline is connected to the semi-coke conveying pipeline so that the desorption gas blows the separated coke powder into the boiler, and / or the desorption gas conveying pipeline is connected to the coal slime conveying pipeline so that the desorption gas blows the crushed coal slime powder into the boiler.

3. The coal pyrolysis quality separation and polygeneration synergistic coupling system according to claim 2 is characterized in that: The coupling system further includes a hot flue gas delivery pipe and a heat exchanger. The hot flue gas delivery pipe is connected to the flue gas outlet of the boiler and is used to deliver the hot flue gas generated by combustion in the boiler to the outside. The hot flue gas delivery pipe and the desorbed gas delivery pipe are both connected to the heat exchanger to transfer the heat of the hot flue gas to the desorbed gas through the heat exchanger.

4. The coal pyrolysis quality separation and polygeneration synergistic coupling system according to claim 1 is characterized in that: The coal slime storage bin is connected to a drying device, and the drying device is used to dry the coal slime; The coupling system further includes a hot flue gas conveying pipeline, which is connected to the flue gas outlet of the boiler and is used to convey the hot flue gas generated by the combustion of the boiler to the outside; the hot flue gas conveying pipeline is connected to the drying device to use the hot flue gas to dry the coal slime.

5. A synergistic coupling process for coal pyrolysis, quality separation and multi-generation, characterized in that: include: Washing of raw coal produces clean coal and coal slime; The clean coal is pyrolyzed, and the pyrolysis products are separated to obtain semi-coke and pyrolysis gas, and hydrogen in the pyrolysis gas is removed to obtain desorbed gas; The semi-coke, coal slime and desorbed gas are fed into the boiler for combustion to generate electricity; The boiler includes a pulverized coal boiler and / or a fluidized bed boiler; When the boiler comprises a pulverized coal furnace, the process further comprises: pulverizing the coal slime to obtain coal slime powder; Pulverizing the clean coal and obtaining fine coke after pyrolysis; Using the desorbed gas, the coal slurry powder and / or fine coke is blown into the boiler for combustion; The process further comprises: collecting hot flue gas generated by boiler combustion, and transferring the heat of the hot flue gas to the desorbed gas using a heat exchanger to preheat the desorbed gas; And / or, hot flue gas generated by boiler combustion is collected and used to dry the washed coal slime.

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