Supercritical thermal power generating unit cooperative power generation and hydrogen production system

Abstract

The invention relates to the technical field of coal-fired thermal power generation and supercritical water gasification hydrogen production, in particular to a supercritical thermal power generating unit cooperative power generation and hydrogen production system. The system comprises a steam conveying system, a reaction device, a material conveying system, a product waste heat utilization system and a product separation system, the steam conveying system is connected with a steam inlet of the reaction device; the product waste heat utilization system comprises a material preheating device, a first heat exchange unit and a second heat exchange unit; the material preheating device is connected with the material conveying system and the first heat exchange unit; the first heat exchange unit is connected with the reaction device; a discharge hole of the reaction device is respectively connected with the material preheating device and the first heat exchange unit; the first heat exchange unit is connected with the second heat exchange unit, and the second heat exchange unit is connected with the product separation system. According to the invention, the residual steam is used for efficiently producing hydrogen from the coal slime wastewater while the safe load operation of the boiler is ensured, so that the hydrogen production efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of coal-fired thermal power generation and supercritical water gasification hydrogen production, and in particular to a supercritical thermal power unit coordinated power generation and hydrogen production system. Background Art

[0002] In order to ensure the transformation of energy to clean and green, coal-fired power generation units will transform to basic security and system regulation power sources in the future, give full play to the flexible operation capacity of thermal power units, and deep peak regulation will be the normal operation of coal-fired units. In the form of deep peak regulation, power plant boilers will inevitably operate alternately at full load and low loads that are greatly different from the design load, and sometimes even operate for a long time at a lower load of 25% to 15%. In this variable load and lower load operation, it is particularly easy to cause unstable combustion operation in the boiler furnace, causing the boiler heating surface to serve in an environment with frequent temperature changes, increasing the risk of high-temperature heating surface tube bursts and creep fracture failure accidents on the boiler's high-temperature heating surface.

[0003] The coal in the power plant contains a large amount of coal slime wastewater. Therefore, in order to reduce the operating risk of the boiler under variable load and low load, the power plant can maintain the boiler operating under a relatively safe and economical load. While ensuring the power supply load, the remaining load can be used to produce hydrogen from the coal slime wastewater using supercritical water. This can achieve the utilization of the remaining load while ensuring the power supply load, obtain a certain amount of economic income, and improve the economy of the power plant.

[0004] Supercritical water gasification is called supercritical water gasification, or SCWG for short. SCWG can convert organic matter, such as coal, into a hydrogen-rich mixed gas containing hydrogen, carbon dioxide, methane, carbon monoxide and other gases, and has received extensive attention in green and efficient H2 production applications. However, the equipment manufacturing and operating costs of the supercritical water gasification hydrogen production process are relatively high, making the construction of a separate supercritical water gasification hydrogen production device less economical.

[0005] In addition, the existing coal-fired power unit coupled supercritical water hydrogen production system fails to efficiently utilize the reaction waste heat, has high energy consumption, and the produced hydrogen is often impure, which reduces the hydrogen production efficiency. Therefore, the development of an efficient and energy-saving supercritical hydrogen production system has become an important technical direction. Summary of the invention

[0006] In order to solve the problems of safe operation of boiler with variable load and low efficiency and high operation cost of coupled hydrogen production of coal-fired power units, the object of the present invention is to provide a system for coordinated power generation and hydrogen production of supercritical thermal power units.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows.

[0008] The first aspect of the present invention provides a supercritical thermal power unit coordinated power generation and hydrogen production system, comprising a steam transport system, a reaction device, a material transport system, a product waste heat utilization system and a product separation system; the steam transport system is connected to the steam inlet of the reaction device; the product waste heat utilization system comprises a material preheating device, a first heat exchange unit and a second heat exchange unit; the first inlet of the material preheating device is connected to the material transport system, and the first outlet of the material preheating device is connected to the first inlet of the first heat exchange unit to heat the material and increase the temperature; the first outlet of the first heat exchange unit is connected to the feed inlet of the reaction device to perform a supercritical water gasification hydrogen production reaction in the reaction device to produce a solid phase product and a gas-liquid Two-phase product; the first discharge port of the reaction device is connected to the second inlet of the material preheating device; the second discharge port of the reaction device is connected to the second inlet of the first heat exchange unit; the second outlet of the first heat exchange unit is connected to the product inlet of the second heat exchange unit, and the product outlet of the second heat exchange unit is connected to the product separation system to separate and store hydrogen; the product separation system includes a hydrogen separation unit, a CO2 separation unit and a solution storage unit; the product outlet of the second heat exchange unit is connected to the hydrogen separation unit, the CO2 separation unit and the solution storage unit in sequence; the outlet of the solution storage unit is connected to the inlet of the salt treatment device, and the outlet of the salt treatment device is connected to the inlet of the material preparation device.

[0009] The present invention utilizes a steam transport system to provide surplus steam generated by surplus load to a reaction device, and carries out supercritical water hydrogen production reaction of coal slime wastewater with materials provided by a material transport system. While ensuring that the boiler operates at a safe load, the surplus steam is used to efficiently produce hydrogen from the coal slime wastewater, thereby improving the hydrogen production efficiency. The problems of safe operation of boilers with variable loads and low efficiency and high operating cost of coupled hydrogen production of coal-fired power units are solved.

[0010] Preferably, the steam transport system comprises a boiler, a first steam output end of the boiler is connected to a steam turbine, and the steam turbine is connected to a generator; and a second steam output end of the boiler is connected to a steam inlet of the reaction device.

[0011] Preferably, the material conveying system includes a material mixing device, a low-pressure delivery pump, a material buffer device, an air compressor and a high-pressure delivery pump, the outlet of the material mixing device is connected to the inlet of the low-pressure delivery pump, the outlet of the low-pressure delivery pump is connected to the first inlet of the material buffer device, the second inlet of the material buffer device is connected to the air compressor to provide air; the first outlet of the material buffer device is connected to the inlet of the high-pressure delivery pump, and the outlet of the high-pressure delivery pump is connected to the first inlet of the material preheating device. The present invention increases the oxygen content of the material and improves the efficiency of supercritical water gasification hydrogen production by adding an air compressor above the material buffer device.

[0012] Preferably, the second outlet of the first heat exchange unit is connected to a salt storage device, and is configured to store the solid phase product in the salt storage device after heat exchange and cooling.

[0013] Preferably, the heat exchange tube inlet of the second heat exchange unit is connected to the condenser rear pipe of the boiler to provide condensed water to the second heat exchange unit; the heat exchange tube outlet of the second heat exchange unit is connected to the purification unit of the power station system. Specifically, the purification unit of the power station system includes a low-pressure heater, a deaerator and a high-pressure heater, which are all equipment in the power station system. The heat exchange tube outlet of the second heat exchange unit is sequentially connected to the low-pressure heater, deaerator and high-pressure heater in the power station system, so that the water after heat exchange is purified by the low-pressure heater, deaerator and high-pressure heater and then re-enters the boiler body.

[0014] Preferably, the product separation system includes a hydrogen separation unit, a CO2 separation unit and a solution storage unit; the product outlet of the second heat exchange unit is connected to the hydrogen separation unit, the CO2 separation unit and the solution storage unit in sequence; the outlet of the solution storage unit is connected to the inlet of the salt treatment device, and the outlet of the salt treatment device is connected to the inlet of the material preparation device. The product separation system of the present invention can obtain relatively pure hydrogen by adding alkali, and relatively pure CO2 by adding acid, and the salt-containing water produced re-enters the material preparation device for material preparation.

[0015] Preferably, the hydrogen separation unit includes a first buffer unit, an alkali solution supply unit and a hydrogen storage unit, the product inlet of the first buffer unit is connected to the product outlet of the second heat exchange unit, the top spray head in the first buffer unit is connected to the alkali solution supply unit through a pipeline, and the hydrogen outlet of the first buffer unit is connected to the hydrogen storage unit.

[0016] Preferably, the CO2 separation unit includes a second buffer unit, an acid liquid supply unit and a CO2 storage unit; the liquid outlet of the first buffer unit is connected to the second buffer unit, the top spray head in the second buffer unit is connected to the acid liquid supply unit, and the CO2 outlet of the second buffer unit is connected to the CO2 storage unit.

[0017] Preferably, a CO2 detection unit is arranged on the pipeline between the first buffer unit and the hydrogen storage unit, a first switch valve is arranged on the pipeline between the first buffer unit and the alkali solution supply unit, and the CO2 detection unit is interlocked with the first switch valve; a second switch valve is arranged on the pipeline between the second buffer unit and the acid solution supply unit, a carbonate ion detection device is provided at the inlet of the solution storage unit, and the carbonate ion detection device is interlocked with the second switch valve.

[0018] Beneficial effects of the present invention:

[0019] 1. The present invention utilizes the steam transport system to provide the reaction device with the surplus steam generated by the surplus load, and carries out the supercritical water hydrogen production reaction of the coal slime wastewater with the material provided by the material transport system. While ensuring the boiler to operate at a safe load, the surplus steam is used to efficiently produce hydrogen from the coal slime wastewater, thereby improving the hydrogen production efficiency; and solving the problems of safe operation of boiler variable load and low efficiency and high operating cost of hydrogen production coupled with coal-fired power units.

[0020] 2. The present invention utilizes the waste heat of the reaction products of supercritical water gasification to produce hydrogen. A part of the waste heat of the products is used to heat the materials, thereby reducing the heat absorption of the materials in the reaction device. The remaining part of the waste heat of the products is used to heat the boiler feed water and enters the low-pressure heater, deaerator and high-pressure heater of the power station system, thereby increasing the temperature of the low-pressure heater and the high-pressure heater, reducing the steam extraction of the steam turbine, and improving the power generation efficiency of the unit.

[0021] 3. The product separation system described in the present invention can separate hydrogen from the product and produce high-purity hydrogen. At the same time, it can capture CO2 in the product and reduce the carbon emissions of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A system schematic diagram of a supercritical thermal power unit coordinated power generation and hydrogen production system provided in an embodiment of the present invention.

[0023] Description of reference numerals:

[0024] 1. Reaction device; 2. Material mixing device; 3. Low-pressure delivery pump; 4. Material buffer device; 5. Air compressor; 6. High-pressure delivery pump; 7. Material preheating device; 8. Salt storage device; 9. Second heat exchange unit; 10. First buffer unit; 11. Alkaline solution supply unit; 12. CO2 detection unit; 13. First heat exchange unit; 14. Hydrogen storage unit; 15. Acid solution supply unit; 16. Second buffer unit; 17. Carbonate ion detection device; 18. CO2 storage unit; 19. Solution storage unit; 20. Deoxygenation and high-pressure heater; 21. Low-pressure heater; 22. Salt treatment device; 23. Boiler; 24. Steam turbine; 25. Generator; V1. Steam switch valve; V2. Exhaust valve; V3. Check valve; V4. First material switch valve; V5. Second material switch valve; V6. Back pressure valve; V7. First pressure reducing valve; V8. First switch valve; V9. Second pressure reducing valve; V10. Second switch valve. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0026] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0027] Supercritical water gasification is called supercritical water gasification, or SCWG for short. SCWG can convert organic matter, such as coal, into a hydrogen-rich mixed gas containing hydrogen, carbon dioxide, methane, carbon monoxide and other gases, and has received extensive attention in green and efficient H2 production applications. However, the equipment manufacturing and operating costs of the supercritical water gasification hydrogen production process are relatively high, making the construction of a separate supercritical water gasification hydrogen production device less economical.

[0028] Therefore, by maintaining the boiler at a relatively safe and economical load, while ensuring the power supply load, the boiler's remaining load can be efficiently utilized for supercritical gasification hydrogen production, which can not only ensure the safe operation of the boiler when the load changes, but also enable the power plant to obtain a certain economic income and improve the economy of the power plant. In addition, the existing coal-fired power unit coupled supercritical water hydrogen production system fails to efficiently utilize the reaction waste heat, has high energy consumption, and the produced hydrogen is often impure, which reduces the efficiency of hydrogen production. Therefore, the development of an efficient and energy-saving supercritical hydrogen production system has become an important technical direction.

[0029] The technical solution of the present invention is further described below by means of specific examples. In the following examples, the methods described are conventional methods unless otherwise specified; the reagents and materials described are commercially available unless otherwise specified.

[0030] like Figure 1A supercritical thermal power unit coordinated power generation and hydrogen production system, comprising a steam transport system, a reaction device 1, a material transport system, a product waste heat utilization system and a product separation system; the steam transport system is connected to the steam inlet of the reaction device 1; the product waste heat utilization system comprises a material preheating device 7, a first heat exchange unit 13 and a second heat exchange unit 9; the first inlet of the material preheating device 7 is connected to the material transport system, and the first outlet of the material preheating device 7 is connected to the first inlet of the first heat exchange unit 13 to heat the material and increase the temperature; the first outlet of the first heat exchange unit 13 is connected to the feed port of the reaction device 1 to perform a supercritical water gasification hydrogen production reaction in the reaction device 1 to produce a solid phase product and a gas-liquid two-phase product; the first discharge port of the reaction device 1 is connected to the second inlet of the material preheating device 7; the second discharge port of the reaction device 1 is connected to the second inlet of the first heat exchange unit 13; the second outlet of the first heat exchange unit 13 is connected to the product inlet of the second heat exchange unit 9, and the product outlet of the second heat exchange unit 9 is connected to the product separation system to separate and store hydrogen.

[0031] Based on the above embodiment, as a more preferred embodiment, the steam transport system includes a boiler 23, the first steam output end of the boiler 23 is connected to the steam turbine 24 to convert thermal energy into mechanical energy, and the rotor of the steam turbine 24 is connected to the rotor of the generator 25 to convert mechanical energy into electrical energy; the second steam output end of the boiler 23 is connected to the steam inlet of the reaction device 1. The second steam output end of the boiler 23 has a steam switch valve V1 to adjust the steam flow entering the reaction device 1.

[0032] Specifically, the boiler 23 is a power station boiler 23. Part of the steam from the boiler 23 is supplied to the steam turbine 24 for generating electricity, and the remaining steam flows through the steam switch valve V1 and enters the reaction device 1. The steam switch valve V1 is interlocked with the operating load of the boiler 23.

[0033] Specifically, the specific process of steam supplying the steam turbine 24 to work and generate electricity is as follows: the first steam output end of the boiler 23 is connected to the steam turbine 24; the high-temperature and high-pressure steam generated by the combustion of fuel in the boiler 23 is the main carrier of thermal energy; the steam drives the blades to rotate in the steam turbine 24 to convert thermal energy into mechanical energy; the rotor of the steam turbine 24 is connected to the generator 25, and the rotational kinetic energy of the rotor of the steam turbine 24 is used to drive the generator 25 to generate electricity, thereby converting mechanical energy into electrical energy. It should be noted that the water in the boiler 23 is heated to boiling and vaporized to form high-temperature and high-pressure steam, which enters the steam turbine 24 through a pipeline; inside the steam turbine 24, the high-temperature and high-pressure steam is sprayed between the blades of the steam turbine 24, and the steam works on the blades, driving the blades to rotate, thereby converting the thermal energy of the steam into mechanical energy. The steam turbine 24 is composed of a rotor and a stator, wherein the rotor of the steam turbine 24 is connected to the rotor of the generator 25. The rotational kinetic energy of the rotor of the steam turbine 24 is transmitted to the rotor of the generator 25 through the shaft. The rotor of the generator 25 is equipped with a wire winding. When the rotor of the generator 25 rotates in the magnetic field, the wire winding cuts the magnetic lines of force to generate an induced electromotive force, thereby generating current. The current generated by the generator 25 is output through the wire and connected to the power grid for people to use.

[0034] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the material conveying system includes a material preparation device 2, a low-pressure delivery pump 3, a material buffer device 4, an air compressor 5 and a high-pressure delivery pump 6. The outlet of the material preparation device 2 is connected to the inlet of the low-pressure delivery pump 3, the outlet of the low-pressure delivery pump 3 is connected to the first inlet of the material buffer device 4, and the second inlet of the material buffer device 4 is connected to the air compressor 5; the first outlet of the material buffer device 4 is connected to the inlet of the high-pressure delivery pump 6, the second outlet of the material buffer device 4 has an exhaust valve V2, and the outlet of the high-pressure delivery pump 6 is connected to the first inlet of the material preheating device 7. The first outlet of the material preheating device 7 is connected to the first inlet of the first heat exchange unit 13, and the first outlet of the first heat exchange unit 13 is connected to the reaction device 1.

[0035] Specifically, the material preparation device 2 is used to prepare the ratio of coal slime and wastewater as materials for supercritical water hydrogen production. Among them, the wastewater is specifically coal slime wastewater generated by the power plant. After the prepared material enters the material preparation device 2, it is transported to the material buffer device 4 by the low-pressure delivery pump 3. An air compressor 5 is arranged above the material buffer device 4. The air compressor 5 is used to provide air to the material buffer device 4 to increase the oxygen content of the material. In order to improve safety, an exhaust valve V2 is arranged above the material buffer device 4 to adjust the pressure in the material buffer device 4. The material in the material buffer device 4 is transported by the high-pressure delivery pump 6, and after passing through the check valve V3 and the first material switch valve V4, it is transported to the material preheating device 7. The material preheating device 7 can preheat the material and transport the preheated material to the first heat exchange unit 13. The first heat exchange unit 13 can further heat exchange and heat up the material so that the material enters the reaction device 1 through the material switch valve V5 after reaching a certain temperature. Among them, the medium-pressure delivery pump 3 and the high-pressure delivery pump 6 are interlocked with the steam switching valve V1.

[0036] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the product waste heat utilization system includes a material preheating device 7 and a first heat exchange unit 13. The first inlet of the material preheating device 7 is connected to the high-pressure delivery pump 6 of the material delivery system, and the first outlet of the material preheating device 7 is connected to the first inlet of the first heat exchange unit 13 to heat the material and raise its temperature; the first outlet of the first heat exchange unit 13 is connected to the feed port of the reaction device 1 to further heat the material and then feed it into the reaction device 1. The second inlet of the material preheating device 7 is connected to the first discharge port of the reaction device 1, and the second outlet of the material preheating device 7 is connected to the salt storage device 8 to store the solid phase product obtained by the reaction of the reaction device 1 after heat exchange and cooling. The second discharge port of the reaction device 1 is connected to the second inlet of the first heat exchange unit 13.

[0037] Specifically, the product waste heat utilization system includes a first heat exchange unit 13 and a material preheating device 7 below the reaction device 1. The material preheating device 7 is used to preheat the material, and then the material is sent to the reaction device 1 after heat exchange and temperature increase again in the first heat exchange unit 13, thereby improving the reaction efficiency and energy utilization. The material in the reaction device 1 undergoes a supercritical water gasification reaction with supercritical steam to produce a solid-phase product and a gas-liquid two-phase product. The solid-phase product obtained by the reaction of the reaction device 1 is heat exchanged and cooled by the material preheating device 7, and then enters the salt storage device 8 provided below the material preheating device 7 for storage. The gas-liquid two-phase product obtained by the reaction of the reaction device 1 is heat exchanged and cooled by the first heat exchange unit 13 and then sent to the second heat exchange unit 9.

[0038] On the basis of the above-mentioned embodiment, as a more preferred embodiment, the product waste heat utilization system further includes a second heat exchange unit 9, the second inlet of the first heat exchange unit 13 is connected to the second discharge port of the reaction device 1, the second outlet of the first heat exchange unit 13 is connected to the product inlet of the second heat exchange unit 9, and the product outlet of the second heat exchange unit 9 is connected to the product separation system. The heat exchange tube inlet of the second heat exchange unit 9 is connected to the condenser rear pipeline of the boiler, the heat exchange tube outlet of the second heat exchange unit 9 is connected to the inlet of the purification unit of the power station system, and the outlet of the purification unit is connected to the water inlet of the boiler. Specifically, the purification unit of the power station system includes a low-pressure heater, a deaerator and a high-pressure heater, which are all equipment in the power station system, and the heat exchange tube outlet of the second heat exchange unit is sequentially connected to the low-pressure heater, the deaerator and the high-pressure heater in the power station system, so that the water after heat exchange is purified by the low-pressure heater, the deaerator and the high-pressure heater and then re-enters the boiler body.

[0039] Specifically, the product outlet of the first heat exchange unit 13 is connected to the product inlet of the second heat exchange unit 9, and then the product outlet of the second heat exchange unit 9 is connected to the product separation system. Among them, the heat exchange medium of the second heat exchange unit 9 is the condensate of the boiler 23, which is provided by the boiler feed water system. The gas-liquid two-phase product in the reaction device 1 is sent to the second heat exchange unit 9 after heat exchange and cooling in the first heat exchange unit 13, and heat exchange is carried out with the condensate provided by the pipeline after the condenser of the boiler. The condensate after heat exchange enters the low-pressure heater 21, deaerator and high-pressure heater 20 of the power station system in turn, and finally enters the boiler 23.

[0040] On the basis of the above embodiment, as a more preferred embodiment, the product separation system includes a hydrogen separation unit, a CO2 separation unit and a solution storage unit 19; the product outlet of the second heat exchange unit 9 is sequentially connected to the hydrogen separation unit, the CO2 separation unit and the solution storage unit 19. The outlet of the solution storage unit 19 is connected to the inlet of the salt treatment device 22, and the outlet of the salt treatment device 22 is connected to the inlet of the material preparation device 2.

[0041] Specifically, the hydrogen separation unit is used to separate and store hydrogen; the CO2 separation unit is used to separate and store CO2; and the solution storage unit 19 is used to store the remaining salt solution after separation. The salt solution stored in the solution storage unit 19 is then treated by the salt treatment device 22 and re-enters the material preparation device 2. Among them, the salt treatment device 22 is used to remove excess salt in the water. The salt treatment device 22 is an existing desalination device, such as an ion exchange desalination device, a reverse osmosis desalination device, etc. on the market.

[0042] On the basis of the above embodiment, as a more preferred embodiment, the hydrogen separation unit includes a first buffer unit 10, an alkali solution supply unit 11 and a hydrogen storage unit 14, the product inlet of the first buffer unit 10 is connected to the product outlet of the second heat exchange unit 9, the top spray head in the first buffer unit 10 is connected to the alkali solution supply unit 11 through a pipeline, and the hydrogen outlet of the first buffer unit 10 is connected to the hydrogen storage unit 14.

[0043] Specifically, a back pressure valve V6 and a first pressure reducing valve V7 are arranged on the pipeline between the second heat exchange unit 9 and the first buffer unit 10, and the gas-liquid two-phase product passes through the back pressure valve V6 and the first pressure reducing valve V7 in sequence and then enters the first buffer unit 10. An alkali liquid supply unit 11 is arranged above the first buffer unit 10, and the alkali liquid sprays the hydrogen in the first buffer unit 10, and the generated high-purity hydrogen enters the hydrogen storage unit 14.

[0044] On the basis of the above embodiment, as a more preferred embodiment, a CO2 detection unit 12 is arranged on the pipeline between the first buffer unit 10 and the hydrogen storage unit 14, and a first switch valve V8 is arranged on the pipeline between the first buffer unit 10 and the alkali solution supply unit 11. The CO2 detection unit 12 is connected to the first switch valve V8 through a wire to control the opening and closing of the first switch valve V8.

[0045] Specifically, the CO2 detection unit 12 is used to detect the gas entering the hydrogen storage unit 14, so that hydrogen that meets the purity requirements enters the hydrogen storage unit 14 through the pipeline. When the CO2 detection unit 12 detects that the hydrogen purity is lower than the set requirement, the CO2 detection unit 12 controls the first switch valve V8 to open to remove CO2 in the gas and further improve the purity of the hydrogen.

[0046] On the basis of the above embodiment, as a more preferred embodiment, the CO2 separation unit includes a second buffer unit 16, an acid liquid supply unit 15 and a CO2 storage unit 18; the liquid outlet of the first buffer unit 10 is connected to the second buffer unit 16, the top spray head in the second buffer unit 16 is connected to the acid liquid supply unit 15, and the CO2 outlet of the second buffer unit 16 is connected to the CO2 storage unit 18.

[0047] Specifically, a second pressure reducing valve V9 is disposed on the pipeline between the first buffer unit 10 and the second buffer unit 16. The liquid product from the first buffer unit 10 is CO2 and salt solution after passing through the second pressure reducing valve V9, and enters the second buffer unit 16, and all CO2 in the product is precipitated through the acid supply unit 15 and stored in the CO2 storage unit 18.

[0048] On the basis of the above embodiment, as a more preferred embodiment, a second switch valve V10 is arranged on the pipeline between the second buffer unit 16 and the acid supply unit 15, and a carbonate ion detection device 17 is provided at the inlet of the solution storage unit 19. The carbonate ion detection device 17 is connected to the second switch valve V10 through a wire to control the opening and closing of the second switch valve V10.

[0049] Specifically, the carbonate ion detection device 17 is used to detect the liquid entering the solution storage unit 19. The carbonate ion detection device 17 arranged in front of the solution storage unit 19 is interlocked with the second switch valve V10. When a higher concentration of carbonate ions is detected, the second switch valve V10 is opened to allow all CO2 dissolved in the water to precipitate.

[0050] In the embodiment of the present invention, the gas-liquid two-phase product passes through the back pressure valve V6 and the first pressure reducing valve V7 in sequence and then enters the first buffer unit 10. An alkali solution supply unit 11 is arranged above the first buffer unit 10. The alkali solution sprays the hydrogen in the first buffer unit 10, and the generated high-purity hydrogen enters the hydrogen storage unit 14. A CO2 detection unit 12 is arranged in front of the hydrogen storage unit 14. The remaining liquid phase product passes through the second pressure reducing valve V9 and enters the second buffer unit 16. The second buffer unit 16 is provided with an acid supply unit 15. The CO2 generated in the second buffer unit 16 enters the CO2 storage unit 18; the remaining salt solution enters the solution storage unit 19, and then passes through the salt treatment device 22 and re-enters the material preparation device 2; wherein, a CO2 detection unit 12 is arranged at the inlet of the hydrogen storage unit 14, and the CO2 detection unit 12 is interlocked with the first switch valve V8. A carbonate ion detection device 17 is arranged at the inlet of the solution storage unit 19, and the carbonate ion detection device 17 is interlocked with the second switch valve V10.

[0051] The specific implementation of the supercritical thermal power unit coordinated power generation and hydrogen production system is as follows:

[0052] When the boiler 23 needs to reduce the power generation load while operating under the safe load, the boiler 23 can be maintained under the safe load, a part of the steam is used to supply the steam turbine 24 with power generation, and the remaining steam passes through the steam switch valve V1 interlocked with the power generation load of the boiler 23 and enters the reaction device 1 for supercritical water gasification hydrogen production reaction.

[0053] At the same time, the low-pressure delivery pump 3 and the high-pressure delivery pump 6 interlocked with the steam switch valve V1 are opened at a certain flow rate, and the low-pressure delivery pump 3 delivers wastewater and coal slime to the material buffer device 4. An air compressor 5 is arranged above the material buffer device 4 to increase the oxygen content in the material and improve the efficiency of hydrogen production by supercritical water gasification, and an exhaust valve V2 is arranged on the top of the buffer tank 4. The material coming out of the material buffer device 4 is pressurized to the reaction pressure by the high-pressure delivery pump 6, and then passes through the check valve V3 and the material switch valve V4 in sequence to enter the material preheating device 7, and after coming out of the material preheating device 7, enters the first heat exchange unit 13 for heat exchange, passes through the second material switch valve V5, and finally enters the reaction device 1 to undergo supercritical water gasification reaction with supercritical steam.

[0054] The solid phase product in the reaction product passes through the material preheating device 7 and then enters the salt storage device 8. The gas-liquid two-phase product passes through the first heat exchange unit 13 to exchange heat with the material, and then enters the second heat exchange unit 9 to exchange heat with the boiler feed water. The heated feed water enters the low-pressure heater 21, the deaerator and the high-pressure heater 20 in turn, and then enters the boiler 23, thereby increasing the steam temperature of the low-pressure heater 21, reducing the steam extraction of the turbine 24, and improving the power generation efficiency of the unit.

[0055] The gas-liquid two-phase products after cooling are separated. The gas-liquid two-phase products at the outlet of the second heat exchange unit 9 pass through the back pressure valve V6 and the first pressure reducing valve V7 and enter the first buffer unit 10. The gas product hydrogen from the first buffer unit 10 enters the hydrogen storage unit 14. An alkali solution supply unit is arranged above the first buffer unit 10, which is interlocked with the CO2 detection unit 12 at the inlet of the hydrogen storage unit 14. When CO2 is detected, the first switch valve V8 is opened, and the alkali solution is sprayed above the first buffer unit 10 to absorb the CO2 in the gas product. The liquid product from the first buffer unit 10 passes through the second pressure reducing valve V9 and becomes CO2 and salt solution, which enters the second buffer unit 16. All CO2 in the product is precipitated through the acid supply unit 15, and the salt solution is stored in the solution storage unit 19. Finally, the salt solution of the solution storage unit 19 passes through the salt treatment device 22 and enters the material preparation device 2. The carbonate ion detection device 17 disposed in front of the solution storage unit 19 is interlocked with the second switch valve V10. When a certain concentration of carbonate ions is detected, the second switch valve V10 is opened to allow all CO2 dissolved in water to precipitate out.

[0056] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A supercritical thermal power unit coordinated power generation and hydrogen production system, characterized in that: It comprises a steam transport system, a reaction device (1), a material transport system, a product waste heat utilization system and a product separation system; the steam transport system is connected to the steam inlet of the reaction device (1); The product waste heat utilization system comprises a material preheating device (7), a first heat exchange unit (13) and a second heat exchange unit (9); the first inlet of the material preheating device (7) is connected to the material conveying system, and the first outlet of the material preheating device (7) is connected to the first inlet of the first heat exchange unit (13) to heat the material and raise its temperature; the first outlet of the first heat exchange unit (13) is connected to the feed inlet of the reaction device (1) to perform a supercritical water gasification hydrogen production reaction in the reaction device (1) to produce a solid phase product and a gas-liquid two-phase product; The first discharge port of the reaction device (1) is connected to the second inlet of the material preheating device (7); the second discharge port of the reaction device (1) is connected to the second inlet of the first heat exchange unit (13); The second outlet of the first heat exchange unit (13) is connected to the product inlet of the second heat exchange unit (9), and the product outlet of the second heat exchange unit (9) is connected to the product separation system to separate and store hydrogen; The product separation system comprises a hydrogen separation unit, a CO2 separation unit and a solution storage unit (19); the product outlet of the second heat exchange unit (9) is connected to the hydrogen separation unit, the CO2 separation unit and the solution storage unit (19) in sequence; the outlet of the solution storage unit (19) is connected to the inlet of the salt treatment device (22), and the outlet of the salt treatment device (22) is connected to the inlet of the material preparation device (2).

2. The supercritical thermal power unit coordinated power generation and hydrogen production system according to claim 1 is characterized in that: The steam transport system comprises a boiler (23), a first steam output end of the boiler (23) is connected to a steam turbine (24), and the steam turbine (24) is connected to a generator (25); a second steam output end of the boiler (23) is connected to a steam inlet of the reaction device (1).

3. The supercritical thermal power unit coordinated power generation and hydrogen production system according to claim 1, characterized in that: The material conveying system comprises a material mixing device (2), a low-pressure conveying pump (3), a material buffer device (4), an air compressor (5) and a high-pressure conveying pump (6), wherein the outlet of the material mixing device (2) is connected to the inlet of the low-pressure conveying pump (3), the outlet of the low-pressure conveying pump (3) is connected to the first inlet of the material buffer device (4), and the second inlet of the material buffer device (4) is connected to the air compressor (5) to provide air; The first outlet of the material buffer device (4) is connected to the inlet of the high-pressure delivery pump (6), and the outlet of the high-pressure delivery pump (6) is connected to the first inlet of the material preheating device (7).

4. The supercritical thermal power unit coordinated power generation and hydrogen production system according to claim 1, characterized in that: The second outlet of the first heat exchange unit (13) is connected to a salt storage device (8) and is configured to store the solid phase product in the salt storage device (8) after heat exchange and temperature reduction.

5. The supercritical thermal power unit coordinated power generation and hydrogen production system according to claim 2, characterized in that: The heat exchange tube inlet of the second heat exchange unit (9) is connected to the condenser rear pipe of the boiler (23) to provide condensed water to the second heat exchange unit (9); the heat exchange tube outlet of the second heat exchange unit (9) is connected to the purification unit of the power station system.

6. The supercritical thermal power unit coordinated power generation and hydrogen production system according to claim 1, characterized in that: The hydrogen separation unit comprises a first buffer unit (10), an alkali solution supply unit (11) and a hydrogen storage unit (14); the product inlet of the first buffer unit (10) is connected to the product outlet of the second heat exchange unit (9); the top spray head in the first buffer unit (10) is connected to the alkali solution supply unit (11) through a pipeline; and the hydrogen outlet of the first buffer unit (10) is connected to the hydrogen storage unit (14).

7. The supercritical thermal power unit coordinated power generation and hydrogen production system according to claim 6, characterized in that: The CO2 separation unit comprises a second buffer unit (16), an acid liquid supply unit (15) and a CO2 storage unit (18); the liquid outlet of the first buffer unit (10) is connected to the second buffer unit (16), the top spray head in the second buffer unit (16) is connected to the acid liquid supply unit (15), and the CO2 outlet of the second buffer unit (16) is connected to the CO2 storage unit (18).

8. The supercritical thermal power unit coordinated power generation and hydrogen production system according to claim 7, characterized in that: A CO2 detection unit (12) is arranged on the pipeline between the first buffer unit (10) and the hydrogen storage unit (14), a first switch valve is arranged on the pipeline between the first buffer unit (10) and the alkali solution supply unit (11), and the CO2 detection unit (12) is interlocked with the first switch valve; A second switch valve is arranged on the pipeline between the second buffer unit (16) and the acid solution supply unit (15), and a carbonate ion detection device (17) is provided at the inlet of the solution storage unit (19), and the carbonate ion detection device (17) is interlocked with the second switch valve.

Images