Efficient treatment and resource utilization system of coal gasification slag

Abstract

The present application relates to waste resource utilization technical field, specifically to a kind of coal gasification slag efficient treatment and resource utilization system.The system includes: gasification slag hydrothermal treatment system, including multiple reaction devices, the first inlet of each reaction device is connected gasification slag feeding pipe, the second inlet of each reaction device is connected steam pipe;Cooling circulation system, including water storage tank and heat exchanger;The first outlet of water storage tank is connected with multiple water supply pipes, each water supply pipe is connected with the third inlet of its corresponding reaction device;The second outlet of water storage tank is connected with multiple cooling water pipes, each cooling water pipe is sequentially passed through with its corresponding reaction device and heat exchanger, and is connected with the first inlet of water storage tank.The system of the present application solves the problem of resource waste caused by the unreasonable treatment of gasification slag at present and the safe operation of boiler under variable load operating condition and the efficient utilization of remaining load.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waste resource utilization, in particular to a coal gasification slag efficient treatment and resource utilization system. BACKGROUND

[0002] Clean and efficient utilization of coal is an important way to promote energy green and low-carbon transformation. Coal gasification technology, as one of the most promising coal chemical technologies, is a key technology to achieve clean and efficient utilization of coal. Because coal contains a certain amount of inorganic minerals, and in the gasification process, organic matter in coal cannot be completely converted, coal gasification technology will also produce a large amount of gasification slag while preparing synthesis gas. Gasification slag is composed of inorganic minerals and residual carbon, and can be divided into coarse slag and fine slag according to the slag discharge position. According to statistics, the annual emission of gasification slag is about 330 million tons, with huge output; and the formation of gasification slag is closely related to raw coal and gasification process conditions, and the structure is complex and variable. Therefore, the utilization of gasification slag is one of the current problems of coal gasification technology.

[0003] In addition, the current disposal methods of stacking and landfill not only pollute the ecological environment, but also waste resources. Therefore, how to resource utilization of gasification slag, that is, effectively utilizing the residual carbon and silicon-aluminum elements and other components of gasification slag is a problem that needs to be solved at present. Preparing high-value functional composite materials and applying them to CO2 capture and wastewater treatment in the coal chemical process can achieve the purpose of waste control.

[0004] At present, when the coal-fired boiler generates electricity and provides heat, the load of the coal-fired boiler may change frequently due to user demand. Under the variable load operation condition, the coal-fired boiler is prone to accidents such as furnace flameout and corrosion failure of key components, which not only affects the safe operation of the coal-fired boiler, but also reduces the operation efficiency of the boiler and increases the operation cost of the coal-fired boiler. SUMMARY

[0005] In order to solve the problem of resource waste caused by unreasonable treatment of gasification slag and the problem of safe operation of the boiler under variable load operation condition, the purpose of the present application is to maintain the safe load of the boiler, efficiently utilize the remaining load on the basis of meeting the required power generation load, and provide a coal gasification slag efficient treatment and resource utilization system.

[0006] The system of the present application maintains the safe and economic load operation of the coal-fired boiler, a part of the load meets the heating and power generation demand, and the remaining load is used for resource recovery of gasification slag to generate certain economic income, which not only increases the safety of the boiler operation, but also improves the economy of the coal-fired boiler.

[0007] To achieve the above purpose, the technical scheme of the present application is as follows.

[0008] The first aspect of the present application provides a coal gasification slag efficient treatment and resource utilization system, comprising: a gasification slag hydrothermal treatment system, comprising a plurality of reaction devices, the first inlet of each reaction device is connected to a gasification slag supply pipeline, and the second inlet of each reaction device is connected to a steam pipeline; a cooling circulation system comprising a water storage tank and a heat exchanger; a plurality of water supply pipelines are connected to the first outlet of the water storage tank, and each water supply pipeline is connected to the third inlet of the corresponding reaction device; a plurality of cooling water pipelines are connected to the second outlet of the water storage tank; each cooling water pipeline sequentially passes through the corresponding reaction device and the heat exchanger, and is connected to the first inlet of the water storage tank.

[0009] The present application uses the gasification slag hydrothermal treatment system to hydrothermally treat the gasification slag, so as to realize the treatment of the gasification slag waste, so that the treated gasification slag has a certain economic value. At the same time, the water required for the reaction in the gasification slag hydrothermal treatment system comes from the residual load steam corresponding to the residual load of the boiler and the boiler feed water, so that the boiler can be operated under safe load, and the residual load of the boiler can be efficiently utilized to treat the gasification slag waste, so as to realize the recycling and reuse of the treated gasification slag, and achieve certain economic benefits. The heat generated during the hydrothermal treatment of the gasification slag can be provided to the heat exchanger through the cooling water pipeline, and the waste heat of the reaction device can be reused through the heat exchanger, thereby improving the energy utilization efficiency and the safety of the system operation, and solving the problems of resource waste caused by the unreasonable treatment of the gasification slag and the safe operation of the boiler under variable load conditions.

[0010] Preferably, the inlet end of each gasification slag supply pipeline is connected to the gasification slag outlet of the gasification furnace; and the inlet end of each steam pipeline is connected to the steam outlet of the boiler.

[0011] The present application uses part of the steam in the boiler to continuously treat the gasification slag waste generated in the gasification furnace, can efficiently and low-carbon treat the gasification slag waste, prepare high-value functional composite materials, and realize the recycling and utilization of the gasification slag waste.

[0012] Preferably, the steam outlet of the boiler is connected to the steam inlet of the gasification furnace through a steam pipeline to provide steam. The system of the present application can realize the high-value utilization of the gasification slag generated by the gasification furnace, and fully utilize the residual load of the boiler to improve the economy of the coal-fired boiler.

[0013] Preferably, the water inlet of the heat exchanger is connected to the boiler feed water system, and the water outlet of the heat exchanger is connected to the water inlet of the boiler.

[0014] Preferably, the cooling circulation system comprises a water deep treatment device, a water inlet of the water deep treatment device is connected with the third outlet of the water storage tank, and a water outlet of the water deep treatment device is connected with a boiler desalted water mother pipe.

[0015] Preferably, a gasification slag outlet of the gasification furnace is connected with an inlet of a gasification slag bin, and an outlet of the gasification slag bin is connected with a plurality of gasification slag feeding pipes respectively.

[0016] Preferably, a part of each of the cooling water pipes is coiled on an outer wall of the corresponding reaction device, and another part of each of the cooling water pipes is coiled in the heat exchanger.

[0017] Preferably, each of the reaction devices is provided with a temperature sensor and a pressure sensor, a reaction temperature in each of the reaction devices is 200-300 DEG C, and a reaction pressure in each of the reaction devices is 1.80-8.90 MPa.

[0018] In the present application, the reaction pressure in each of the reaction devices is 1.80-8.90 MPa, so as to effectively maintain the reaction medium in a subcritical state.

[0019] Preferably, the coal gasification slag efficient treatment and resource utilization system comprises a product collection system, the product collection system comprises a vacuum conveying belt and a product collection device, a discharge outlet of each of the reaction devices is connected with the vacuum conveying belt, a liquid outlet of the vacuum conveying belt is connected with a second inlet of the water storage tank, a solid outlet of the vacuum conveying belt is arranged at a feeding end of the product conveying device and is configured to provide the separated solid product to the vacuum conveying belt, and a discharge end of the vacuum conveying belt is arranged at a feeding inlet of the product collection device and is configured to convey the solid product on the vacuum conveying belt into the product collection device.

[0020] Preferably, each of the gasification slag feeding pipes, the steam pipes, the water feeding pipes and the cooling water pipes is provided with a control valve.

[0021] The present application has the following beneficial effects:

[0022] 1、The present application realizes the treatment of gasification slag waste by hydrothermal treatment of gasification slag through a gasification slag hydrothermal treatment system, so that the treated gasification slag has certain economic value. At the same time, the water required for the reaction in the gasification slag hydrothermal treatment system comes from the residual load steam corresponding to the residual load of the boiler and the boiler feed water, so that the boiler can be operated under safe load, and the residual load of the boiler can be efficiently utilized to treat the gasification slag waste, so as to realize the recycling and reuse of the treated gasification slag, and achieve certain economic benefits. The heat generated in the hydrothermal treatment process of the gasification slag can be provided to the heat exchanger through the cooling water pipeline, and the waste heat of the reaction device is recycled through the heat exchanger, so as to improve the energy utilization efficiency and the safety of the system operation, and solve the problems of resource waste caused by unreasonable treatment of gasification slag and safe operation of the boiler under variable load conditions.

[0023] 2、The present application realizes the continuous treatment of gasification slag by setting multiple reactors, so as to realize the continuous treatment of gasification slag, ensure the efficient output of gasification slag, and realize the treatment and resource utilization of gasification slag waste.

[0024] 3、The present application realizes the recycling of the water generated after treating the gasification slag, and the water after reaction can be used to cool the reaction device, realize the safe discharge of the reaction device, and indirectly heat the boiler feed water by using the waste heat of the reaction device, so as to improve the thermal efficiency of the boiler. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The system arrangement drawing of the coal gasification slag efficient treatment and resource utilization system provided by an embodiment of the present application.

[0026] BRIEF DESCRIPTION OF DRAWINGS

[0027] 1、gasification furnace;2、gasification slag bin;3、first reaction device;4、second reaction device;5、third reaction device;6、heat exchanger;7、water deep treatment device;8、water storage tank;9、vacuum conveyor belt;10、product collection device;11、boiler;V1、first steam on-off valve;V2、second steam on-off valve;V3、third steam on-off valve;V4、first material slag stop valve;V5、second material slag stop valve;V6、third material slag stop valve;V7、second cooling water on-off valve;V8、cooling water on-off valve D;V9、cooling water on-off valve F;V10、first cooling water on-off valve;V11、third cooling water on-off valve;V12、cooling water on-off valve E;V13、first discharge stop valve;V14、second discharge stop valve;V15、third discharge stop valve. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application.

[0029] All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative labor fall within the scope of protection of the present application.

[0030] At present, the coal-fired boiler may change its load frequently due to user demand when generating electricity and providing heat. Under the variable load operation condition, the coal-fired boiler is prone to accidents such as furnace flameout and corrosion failure of key components, which not only affects the safe operation of the coal-fired boiler, but also reduces the operation efficiency of the boiler and increases the operation cost of the coal-fired boiler. Therefore, when the power generation load needs to be changed, the boiler load can be first operated at a safe load, and on the basis of meeting the required power generation load, the remaining load is efficiently utilized to generate certain economic benefits, which is an important method to solve the safe operation of the boiler when the load needs to be changed.

[0031] The technical solutions of the present application will be further described below through specific embodiments. In each of the following embodiments, the method is a conventional method unless otherwise specified; and the reagents and materials can be purchased on the market unless otherwise specified.

[0032] As Figure 1 A coal gasification slag efficient treatment and resource utilization system, comprising: a gasification slag hydrothermal treatment system and a cooling circulation system. The gasification slag hydrothermal treatment system comprises a plurality of reaction devices, and the first inlet of each reaction device is connected with a gasification slag feeding pipeline, and the second inlet of each reaction device is connected with a steam pipeline; the cooling circulation system comprises a water storage tank 8 and a heat exchanger 6; the first outlet of the water storage tank 8 is connected with a plurality of water supply pipelines, each water supply pipeline is connected with the third inlet of the corresponding reaction device; the second outlet of the water storage tank 8 is connected with a plurality of cooling water pipelines, each cooling water pipeline passes through the corresponding reaction device and the heat exchanger 6 in sequence, and is connected with the first inlet of the water storage tank 8.

[0033] Specifically, the gasification slag hydrothermal treatment system is to hydrothermally treat the gasification slag to realize the treatment of the gasification slag waste, so that the treated gasification slag has certain economic value. The water required for the reaction in the gasification slag hydrothermal treatment system comes from the steam provided by the steam pipeline and the water provided by the water supply pipeline. This treatment method can effectively utilize part of the heat supply load of the boiler 11 to treat the gasification slag waste, so as to realize the recycling and reuse of the treated gasification slag. The preheating generated in the gasification slag hydrothermal treatment process can be provided to the heat exchanger 6 through the cooling water pipeline, and the waste heat of the reaction device is reused through the heat exchanger 6, thereby improving the energy utilization efficiency and the safety of system operation.

[0034] On the basis of the above-mentioned embodiments, as a more preferred embodiment, the reaction device comprises a first reaction device 3, a second reaction device 4 and a third reaction device 5; the gasification slag supply pipeline comprises a first gasification slag supply pipeline, a second gasification slag supply pipeline and a third gasification slag supply pipeline; the outlet of the first gasification slag supply pipeline is connected to the first inlet of the first reaction device 3, the outlet of the second gasification slag supply pipeline is connected to the first inlet of the second reaction device 4, and the outlet of the third gasification slag supply pipeline is connected to the first inlet of the third reaction device 5. The steam pipeline comprises a first steam pipeline, a second steam pipeline and a third steam pipeline; the outlet of the first steam pipeline is connected to the second inlet of the first reaction device 3, the outlet of the second steam pipeline is connected to the second inlet of the second reaction device 4, and the outlet of the third steam pipeline is connected to the second inlet of the third reaction device 5. The water supply pipeline comprises a first water supply pipeline, a second water supply pipeline and a third water supply pipeline; the outlet of the first water supply pipeline is connected to the third inlet of the first reaction device 3, the outlet of the second water supply pipeline is connected to the third inlet of the second reaction device 4, and the outlet of the third water supply pipeline is connected to the third inlet of the third reaction device 5. The cooling water pipeline comprises a first cooling water pipeline, a second cooling water pipeline and a third cooling water pipeline; the outlet of the first cooling water pipeline passes through the first reaction device 3 and the heat exchanger 6 in sequence and is connected to the first inlet of the water storage tank 8, the outlet of the second cooling water pipeline passes through the second reaction device 4 and the heat exchanger 6 in sequence and is connected to the first inlet of the water storage tank 8, and the outlet of the third cooling water pipeline passes through the third reaction device 5 and the heat exchanger 6 in sequence and is connected to the first inlet of the water storage tank 8.

[0035] Specifically, the present application realizes the continuous treatment and resource utilization of the gasification slag waste through three reaction devices. This is mainly because the treatment of the gasification slag waste requires a certain time for reaction, therefore, by arranging multiple reaction devices, the continuous treatment of the gasification slag can be realized to ensure the efficient output of the gasification slag waste and improve the treatment efficiency. Specifically, the reaction device is a reactor that can be directly purchased in the market. The water required for the reaction in the first reaction device 3, the second reaction device 4 and the third reaction device 5 comes from the steam provided by the steam pipeline and the water provided by the water supply pipeline.

[0036] On the basis of the above-mentioned embodiment, as a more preferred embodiment, a part of each cooling water pipe is coiled on the outer wall of the corresponding reaction device; another part of each cooling water pipe is coiled in the heat exchanger 6. Each cooling water pipe comprises a cooling coil and a heat exchange coil, the cooling coil is fixed in the corresponding reactor, and the heat exchange coil is fixed in the heat exchanger 6. Specifically, the cooling coil comprises a first cooling coil, a second cooling coil and a third cooling coil, and is arranged in the corresponding reactor, respectively.

[0037] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the gasification slag supply pipe, the steam pipe, the water supply pipe and the cooling water pipe are provided with control valves.

[0038] Specifically, the first steam pipe is provided with a first steam on-off valve V1, the second steam pipe is provided with a second steam on-off valve V2, and the third steam pipe is provided with a third steam on-off valve V3. The first gasification slag supply pipe is provided with a first slag on-off valve V4, the second gasification slag supply pipe is provided with a second slag on-off valve V5, and the third gasification slag supply pipe is provided with a third slag on-off valve V6. The discharge port of the first reaction device 3 is provided with a first discharge on-off valve V13, the discharge port of the second reaction device 4 is provided with a second discharge on-off valve V14, and the discharge port of the third reaction device 5 is provided with a third discharge on-off valve V15. Specifically, the first slag on-off valve V4 is interlocked with the first steam on-off valve V1, the second slag on-off valve V5 is interlocked with the second steam on-off valve V2, and the third slag on-off valve V6 is interlocked with the third steam on-off valve V3. The first discharge on-off valve V13 is interlocked with the discharge temperature of the first reaction device 3, the second discharge on-off valve V14 is interlocked with the discharge temperature of the second reaction device 4, and the third discharge on-off valve V15 is interlocked with the discharge temperature of the third reaction device 5.

[0039] Specifically, the first reactor has a first cooling coil, the second reactor has a second cooling coil, and the third reactor has a third cooling coil; the inlet end of the first cooling coil has a first cooling water on-off valve V10, and the outlet end of the first cooling coil has a second cooling water on-off valve V7; the inlet end of the second cooling coil has a third cooling water on-off valve V11, and the outlet end of the second cooling coil has a fourth cooling water on-off valve V8; the inlet end of the third cooling coil has a fifth cooling water on-off valve V12, and the outlet end of the third cooling coil has a sixth cooling water on-off valve V9. Specifically, the water storage tank 8 is connected to three cooling water pipelines; the first cooling water pipeline passes through the first cooling water on-off valve V10 and the first cooling coil of the first reaction device 3, and then enters the heat exchanger 6 through the second cooling water on-off valve V7. The second cooling water pipeline passes through the third cooling water on-off valve V11 and the second cooling coil of the second reaction device 4, and then enters the heat exchanger 6 through the fourth cooling water on-off valve V8. The third cooling water pipeline passes through the fifth cooling water on-off valve V12 and the third cooling coil of the third reaction device 5, and then enters the heat exchanger 6 through the sixth cooling water on-off valve V9. The cooling water of the heat exchanger 6 comes from the boiler 11 water supply system. The first cooling water on-off valve V10 and the second cooling water on-off valve V7 are interlocked with the first steam on-off valve 1; the third cooling water on-off valve V11 and the fourth cooling water on-off valve V8 are interlocked with the second steam on-off valve V2; and the fifth cooling water on-off valve V12 and the sixth cooling water on-off valve V9 are interlocked with the third steam on-off valve V3.

[0040] The embodiment of the present application realizes safe operation of the coal gasification slag efficient treatment and resource utilization system through corresponding control valves and interlocking of the corresponding control valves, and improves the safety and efficiency of system operation.

[0041] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the inlet end of each gasification slag supply pipeline is connected to the gasification slag outlet of the gasification furnace 1; and the inlet end of each steam pipeline is connected to the steam outlet of the boiler 11.

[0042] Specifically, the embodiment of the present application connects the gasification furnace 1 and the corresponding reaction device through the gasification slag supply pipeline to provide gasification slag to the corresponding reaction device; and connects the boiler 11 and the reaction device through the steam pipeline to provide high-temperature steam to the corresponding reaction device. This treatment method can effectively utilize part of the heat supply load of the boiler 11 to treat gasification slag waste, so as to realize resource recycling of the treated gasification slag. The embodiment of the present application generates certain economic income by treating gasification slag while generating electricity through the coal-fired boiler 11, thereby improving the safety of the coal-fired boiler 11 operation.

[0043] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the steam outlet of the boiler 11 is connected with the steam inlet of the gasifier 1 through a steam pipeline for providing steam. The pulverized coal supply pipeline is connected with the feed inlet of the gasifier 1, and the gas outlet of the gasifier 1 is connected with the gas pipeline. The embodiment of the present application provides the steam of the boiler 11 to the gasifier 1 through the steam pipeline, uses part of the heat supply load of the boiler 11 to heat treat the pulverized coal to form the gas, and discharges the residual gasification slag from the gasifier 1 and provides the residual gasification slag to the corresponding reaction device through the corresponding gasification slag supply pipeline.

[0044] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the water inlet of the heat exchanger 6 is connected with the feed water system of the boiler 11, and the water outlet of the heat exchanger 6 is connected with the water inlet of the boiler 11.

[0045] Specifically, the feed water system of the boiler 11 is mainly used to provide water to the heat exchanger 6, and the water is heated by the heat exchanger 6 and then provided to the boiler 11. The embodiment of the present application recycles the water generated after the treatment of the gasification slag, uses the reacted water to cool the reactor, realizes the safe discharge of the reactor, indirectly heats the feed water of the boiler 11 by the waste heat of the reactor, and improves the thermal efficiency of the boiler 11.

[0046] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the cooling circulation system comprises a water deep treatment device 7, the water inlet of the water deep treatment device 7 is connected with the third outlet of the water storage tank 8, and the water outlet of the water deep treatment device 7 is connected with the desalted water main pipe of the boiler 11.

[0047] Specifically, the water deep treatment device 7 is mainly used to deeply purify the water in the water storage tank 8, and the deeply purified water is provided to the desalted water main pipe of the boiler 11 and then enters the boiler 11 after being heated by the heat exchanger 6, so as to improve the thermal efficiency of the boiler 11 and realize the recycling of the water. The specific function of the water deep treatment device 7 is to remove the excessive salt in the water, so as to deeply purify the water in the water storage tank 8. The water deep treatment device 7 is an existing desalting device, such as an ion exchange method desalting device, a reverse osmosis method desalting device and the like.

[0048] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the gasification slag outlet of the gasifier 1 is connected with the inlet of the gasification slag bin 2, and the outlet of the gasification slag bin 2 is connected with a plurality of gasification slag supply pipelines.

[0049] Specifically, the gasification slag bin 2 is mainly used to store the gasification slag waste discharged from the gasifier 1, and provides the gasification slag waste to the corresponding gasification slag supply pipeline through the gasification slag bin 2, so as to control the amount of the gasification slag waste entering the corresponding reaction device.

[0050] On the basis of the above-mentioned embodiment, as a more preferred embodiment, each reaction device has a temperature sensor and a pressure sensor; the reaction temperature in each reactor is 200-300 DEG C, and the reaction pressure in each reactor is adjusted to 1.8-8.9 MPa, so that the reaction medium can be effectively maintained in a subcritical state.

[0051] Specifically, the temperature sensor includes a first temperature sensor, a second temperature sensor and a third temperature sensor; the first temperature sensor is arranged in the first reaction device 3 and used for detecting the temperature in the first reaction device 3; the second temperature sensor is arranged in the second reaction device 4 and used for detecting the temperature in the second reaction device 4; and the third temperature sensor is arranged in the third reaction device 5 and used for detecting the temperature in the third reaction device 5. The pressure sensor includes a first pressure sensor, a second pressure sensor and a third pressure sensor; the first pressure sensor is arranged in the first reaction device 3 and used for detecting the pressure in the first reaction device 3; the second pressure sensor is arranged in the second reaction device 4 and used for detecting the pressure in the second reaction device 4; and the third pressure sensor is arranged in the third reaction device 5 and used for detecting the pressure in the third reaction device 5. The embodiment of the application adjusts the temperature and pressure in the corresponding reactor by using the corresponding temperature sensor in combination with the pressure sensor, so as to ensure the normal progress of the reaction.

[0052] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the coal gasification slag efficient treatment and resource utilization system includes a product collection system, the product collection system includes a vacuum conveying belt 9 and a product collection device 10; the discharge port of each reaction device is connected with the vacuum conveying belt 9; the liquid outlet of the vacuum conveying belt 9 is connected with the second inlet of the water storage tank 8; and the solid outlet of the vacuum conveying belt 9 is arranged at the feeding port of the product collection device 10 and configured to convey the solid product on the vacuum conveying belt 9 into the product collection device 10.

[0053] Specifically, the product collection system is mainly used for collecting and treating the solid product after the reaction in the reaction device. The vacuum conveying belt 9 can effectively separate the solid-liquid mixture discharged from the reaction device, and the separated solid product is conveyed into the product collection device 10; and the separated water enters the water storage tank 8.

[0054] The specific implementation operation of the coal gasification slag efficient treatment and resource utilization system is as follows:

[0055] The resource utilization of the gasification slag is realized by extracting part of the steam in the boiler 11 into the gasification furnace 11 for water heat treatment of the gasification slag; and the continuous treatment and recovery of the gasification slag are realized by arranging multiple reactors to ensure the continuous water heat reaction of the gasification slag.

[0056] When the system is started, the first steam switch valve V1 is opened, the first residue cut-off valve V4 interlocked with the first steam switch valve V1 is opened, and the mixture is fed into the first reaction device 3. When the first reaction device 3 is completed, the first steam switch valve V1 and the first residue cut-off valve V4 are closed, at the same time, the second steam switch valve V2 and the second residue cut-off valve V5 interlocked with the second steam switch valve V2 are opened, and the second reaction device 4 is fed. When the second reaction device 4 is completed, the second steam switch valve V2 and the second residue cut-off valve V5 interlocked with the second steam switch valve V2 are closed, at the same time, the third steam switch valve V3 and the third residue cut-off valve V6 interlocked with the third steam switch valve V3 are opened, and the third reaction device 5 is fed. When the third reaction device 5 is completed, the third steam switch valve V3 and the third residue cut-off valve V6 interlocked with the third steam switch valve V3 are closed. The water required by the reaction device is the steam produced by the boiler 11 and the water stored in the water storage tank 8, and the mixture is mixed to make the reaction temperature about 200-300°C, and the reaction pressure is 1.80-8.90 MPa.

[0057] For the first reaction device 3, the following steps are performed:

[0058] After the reaction in the first reaction device 3 is completed, the first cooling water switch valve V10 and the second cooling water switch valve V7 interlocked with the first steam switch valve V1 are opened, that is, the first cooling water switch valve V10 and the second cooling water switch valve V7 are opened at a certain time after the first steam switch valve V1 is closed. Then the water in the water storage tank 8 is used to cool the first reaction device 3, and the cooling water enters the heat exchanger 6 to heat the boiler 11 waste water and finally enters the water storage tank 8.

[0059] After the first reaction device 3 is cooled, the first discharge cut-off valve V13 interlocked with the discharge temperature of the first reaction device 3 is opened, the product is separated by the vacuum conveying belt 9, the solid product is collected in the solid product collecting device 10, and the reaction water enters the water storage tank 8. After the discharge is completed, the first discharge cut-off valve V13 is closed, and at this time the third reaction device 5 is completed.

[0060] Therefore, when the first reaction device 3 is completed, the third reaction device 5 is completed, and the first reaction device 3 can be fed; when the first reaction device 3 is completed, the second reaction device 4 is completed after the similar operation steps as the first reaction device 3, and the second reaction device 4 can be fed; when the second reaction device 4 is completed, the third reaction device 5 is completed after the similar operation steps as the first reaction device 3, and the third reaction device 5 can be fed, and then the cycle is repeated.

[0061] Through the above steps, continuous feeding and treatment of the gasification slag can be realized, efficient treatment and resource utilization of the gasification slag are ensured, and in addition, the excess water of the water storage tank 8 enters the desalted water pipeline of the boiler 11 through the water depth treatment device 7.

[0062] The above only is the preferred embodiment of the present application, and does not limit the present application, any modification, equivalent replacement and improvement within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A coal gasification slag efficient treatment and resource utilization system, characterized in that, The system comprises: a gasification slag hydrothermal treatment system, which comprises a plurality of reaction devices, a first inlet of each of the reaction devices is connected to a gasification slag supply pipeline, and a second inlet of each of the reaction devices is connected to a steam pipeline; an inlet end of each of the steam pipelines is connected to a steam outlet of a boiler (11); each of the reaction devices is provided with a temperature sensor and a pressure sensor; a reaction temperature in each of the reaction devices is 200-300 DEG C, a reaction pressure in each of the reaction devices is 1.80-8.90 MPa, and a reaction medium is maintained in a subcritical state; a cooling circulation system, which comprises a water storage tank (8) and a heat exchanger (6); a first outlet of the water storage tank (8) is connected to a plurality of water supply pipelines, each of the water supply pipelines is connected to a third inlet of a corresponding reaction device; a second outlet of the water storage tank (8) is connected to a plurality of cooling water pipelines; each of the cooling water pipelines sequentially passes through a corresponding reaction device and the heat exchanger (6) and is connected to a first inlet of the water storage tank (8); the cooling circulation system comprises a water deep treatment device (7), a water inlet of the water deep treatment device (7) is connected to a third outlet of the water storage tank (8), and a water outlet of the water deep treatment device (7) is connected to a desalted water main pipeline of the boiler (11); an inlet end of each of the gasification slag supply pipelines is connected to a gasification slag outlet of a gasification furnace (1); the steam outlet of the boiler (11) is connected to the steam inlet of the gasification furnace (1) through a steam pipeline, for providing steam; a water inlet of the heat exchanger (6) is connected to a feedwater system of the boiler (11), and a water outlet of the heat exchanger (6) is connected to a water inlet of the boiler (11); a part of each of the cooling water pipelines is coiled on an outer wall of a corresponding reaction device, and another part of each of the cooling water pipelines is coiled in the heat exchanger (6); the coal gasification slag efficient treatment and resource utilization system comprises a product collection system, the product collection system comprises a vacuum conveying belt (9) and a product collection device (10); a discharge outlet of each of the reaction devices is connected to the vacuum conveying belt (9), and a liquid outlet of the vacuum conveying belt (9) is connected to a second inlet of the water storage tank (8); a discharge end of the vacuum conveying belt (9) is arranged at a feeding inlet of the product collection device (10) and is configured to convey solid products on the vacuum conveying belt (9) into the product collection device (10); the gasification slag is subjected to hydrothermal treatment by the gasification slag hydrothermal treatment system, so that the gasification slag waste is treated; meanwhile, the water required for the reaction in the gasification slag hydrothermal treatment system is obtained from residual load steam corresponding to a residual load of the boiler and boiler feedwater, so that the residual load of the boiler can be efficiently utilized while the boiler is operated under a safe load, the gasification slag waste is treated, and the gasification slag after treatment is recycled and reused; heat generated in the gasification slag hydrothermal treatment process can be provided to the heat exchanger through the cooling water pipelines, the waste heat of the reaction devices is reused through the heat exchanger, and the energy utilization efficiency and the safety of system operation are improved.

2. The coal gasification slag efficient treatment and resource utilization system according to claim 1, characterized in that, The gasification slag outlet of the gasification furnace (1) is connected with the inlet of a gasification slag bin (2), and the outlet of the gasification slag bin (2) is connected with a plurality of gasification slag feeding pipes.

3. The coal gasification slag efficient treatment and resource utilization system according to claim 1, characterized in that, The gasification slag feeding pipe, the steam pipe, the water feeding pipe and the cooling water pipe are all provided with control valves.

Images