Heat pump electricity storage system and method for coupling flue gas waste heat utilization and solid hydrogen ammonia production

Abstract

The invention discloses a heat pump electricity storage system and method for coupling flue gas waste heat utilization and hydrogen fixation ammonia production, and the system comprises a solar heating device, a water electrolysis hydrogen production device, an ammonia synthesis device, a heat pump circulation device, a heat storage circulation device, and an organic Rankine cycle and carbon capture circulation device. The solar heating device, the water electrolysis hydrogen production device, the ammonia synthesis device, the heat pump circulating device, the heat storage circulating device and the organic Rankine cycle and carbon capture circulating device are connected in sequence; heat energy in flue gas waste heat is transferred into a working medium through electric driving, then the heat energy is stored in a high-grade heat energy form, when electric energy needs to be used, the stored heat energy is converted back to the electric energy, energy conversion and storage are achieved, the energy utilization efficiency is improved, utilization of renewable energy sources is supported, the load of a power grid is balanced, and the service life of the power grid is prolonged. The flue gas waste heat of the thermal power plant is recycled, the power generation efficiency of the power plant is improved, and coal consumption is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat pump power storage and waste heat utilization, and specifically relates to a heat pump power storage system and method that couples flue gas waste heat utilization with solid hydrogen production of ammonia. Background Art

[0002] Under the "dual carbon" goal, renewable energy generation technologies including solar and wind power are constantly developing. In this case, emerging energy storage technologies are needed to ensure the stable operation of the power grid. The heat pump power storage system is an energy storage system that stores electrical energy in the form of high-quality thermal energy and releases electricity through a power cycle. Professor Robert called this technology a key technology for storing large amounts of energy in a carbon-neutral energy system.

[0003] This system is driven by electricity, transferring the heat energy from the low-temperature heat source to the working fluid, which is then stored in the form of high-grade heat energy. When electricity is needed, the stored heat energy is converted back into electricity. This process involves energy conversion and storage, aiming to improve energy efficiency, support the use of renewable energy, and balance the load on the power grid.

[0004] Thermal power generation is one of the most common ways of generating electricity in the world. Although it plays an important role in meeting the growing energy needs of mankind, this way of generating electricity also has serious problems of low energy efficiency and environmental pollution. In particular, the problem of waste heat resources generated in the thermal power generation process has attracted widespread attention. In the thermal power generation process, the high-temperature flue gas generated by fuel combustion contains a large amount of heat energy, and the heat energy of these flue gases is often not fully recovered and utilized before being discharged into the atmosphere.

[0005] Traditional waste heat utilization technologies, such as waste heat boilers and heat exchangers, are not very efficient under these low temperature conditions, limiting the scope and efficiency of waste heat recovery. The application of these technologies often requires high initial investment and operation and maintenance costs. For many power generation companies, these costs may exceed the financial budget, resulting in these effective waste heat utilization technologies not being widely used.

[0006] Physical energy storage is currently the most suitable large-scale electricity storage method for peak-shaving, frequency regulation, valley filling and emergency backup of renewable energy power grids; pumped storage and compressed air energy storage are typical large-scale energy storage technologies based on electrical energy → mechanical energy → electrical energy, with high round-trip efficiency and maturity, but their flexible application is limited by geographical factors; and the heat pump energy storage system based on heat pump and organic Rankine cycle is an energy storage technology based on electrical energy → thermal energy → electrical energy, with the advantages of not being restricted by geographical conditions, large storage capacity, high efficiency and long energy storage cycle.

[0007] According to existing standards, hydrogen is positioned as a hazardous chemical and can only be produced in chemical parks, which increases transportation costs. Hydrogen is very active and has extremely poor stability. It is prone to combustion and explosion after leakage. Under high temperature and high pressure, hydrogen can even pass through very thick steel plates. Therefore, hydrogen storage and hydrogen energy transportation are major problems today. Summary of the invention

[0008] The purpose of the present invention is to provide a heat pump power storage system and method that couples flue gas waste heat utilization and solid hydrogen production to ammonia, so as to solve the technical defects in the prior art such as waste of waste heat energy, geographical restrictions on energy storage, low energy utilization efficiency, difficulty in hydrogen storage, grid peak and frequency regulation, and difficulty in carbon capture.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions: In a first aspect, a heat pump power storage system coupling flue gas waste heat utilization and solid hydrogen production of ammonia is provided, comprising: a solar heating device, a water electrolysis hydrogen production device, an ammonia synthesis device, a heat pump circulation device, a heat storage circulation device, an organic Rankine cycle and a carbon capture circulation device, wherein the solar heating device, the water electrolysis hydrogen production device, the ammonia synthesis device, the heat pump circulation device, the heat storage circulation device, the organic Rankine cycle and the carbon capture circulation device are connected in sequence; The solar heating device is used to heat the flue gas, the water electrolysis hydrogen production device is used to use the surplus electricity of the power plant to produce hydrogen and oxygen, and the heat pump circulation device is used to recover the flue gas heat and the heat released during the reaction of the synthetic ammonia device, and to improve the quality of the low-level heat source through electric drive to output high-temperature heat; The heat storage cycle is used to store the high-temperature heat and supply the high-temperature heat to the organic Rankine cycle and the carbon capture cycle device.

[0010] Furthermore, the water electrolysis hydrogen production device is used to receive surplus electricity from the power grid, and electrolyze water using the surplus electricity from the power grid to obtain hydrogen and oxygen, and the oxygen is output as a by-product.

[0011] Furthermore, the ammonia synthesis device includes an ammonia synthesis reactor, a first compressor and a first expander. The first inlet at the bottom of the ammonia synthesis reactor is connected to the first compressor, and the first outlet of the ammonia synthesis reactor is connected to the first expander.

[0012] Further, the heat pump circulation device comprises a second compressor, a first heat exchanger, a second expander, a throttle valve and a second heat exchanger, wherein the second compressor is connected to a third outlet of the second heat exchanger, and the second compressor is also connected to a first inlet of the first heat exchanger; The first outlet of the first heat exchanger is connected to the second expander, and the second expander is connected to the third inlet of the second heat exchanger through the throttle valve.

[0013] Furthermore, the heat storage cycle device includes a first tank body, a third heat exchanger and a second tank body, the first outlet of the first tank body is connected to the first inlet of the third heat exchanger, and the first outlet of the third heat exchanger is connected to the second tank body.

[0014] Further, the organic Rankine cycle includes a third heat exchanger, a third expander, a fourth heat exchanger, a fourth expander, a first condenser and a water pump; The third outlet of the third heat exchanger is connected to the third expander, the third expander is connected to the first inlet of the fourth heat exchanger, and the first outlet of the fourth heat exchanger is connected to the fourth expander; The fourth expander is connected to the first condenser, and the first condenser is connected to the water pump.

[0015] Furthermore, the water pump is connected to the third inlet of the third heat exchanger, and the second outlet of the fourth heat exchanger is connected to the second condenser.

[0016] Furthermore, the carbon capture cycle device includes a CO2 absorption tower, an absorbent regeneration tower, a third compressor and a fifth expander, the second outlet of the CO2 absorption tower is connected to the first inlet of the absorbent regeneration tower, and the second inlet of the CO2 absorption tower is connected to the first outlet of the absorbent regeneration tower.

[0017] Furthermore, the third outlet of the absorbent regeneration tower is connected to the third compressor, and the fifth expander is also connected to the third compressor.

[0018] In the second aspect, a heat pump power storage method for coupling flue gas waste heat utilization carbon capture and solid hydrogen production of ammonia is provided, comprising: The medium-temperature flue gas is heated to a medium-high temperature state, and water is electrolyzed by a water electrolysis hydrogen production device to obtain hydrogen and oxygen; The heated flue gas in a medium-high temperature state is transported to a synthetic ammonia device, so that the medium-high temperature flue gas preheats nitrogen, hydrogen and a mixed gas of nitrogen and hydrogen to obtain a low-temperature and low-pressure mixed gas; The low-temperature and low-pressure mixed gas is subjected to a catalytic reaction and converted into a low-temperature and low-pressure working fluid after heat exchange using a heat pump circulation device; By means of an organic Rankine cycle, the low-temperature and low-pressure working fluid is converted into a low-temperature and medium-pressure organic Rankine cycle working fluid; The low-temperature flue gas is converted into low-temperature and low-pressure carbon dioxide through a carbon capture circulation device and discharged as a product.

[0019] Compared with the prior art, the present invention has the following beneficial effects: 1. Through electric drive, the heat energy in the flue gas waste heat is transferred to the working fluid, and then stored in the form of high-grade heat energy. When electric energy is needed, the stored heat energy is converted back to electric energy, realizing energy conversion and storage, improving energy utilization efficiency, supporting the use of renewable energy, balancing the grid load, and achieving the technical effect of grid peak regulation. Secondly, by recycling the waste heat of flue gas in thermal power plants, the power generation efficiency of power plants is increased by 0.1% to 0.5%, and the standard coal consumption for power generation is reduced by 0.3% to 0.6%. Compared with traditional flue gas recovery devices, the waste heat power generation can be increased by 5% to 20%. In addition, compared with traditional systems, the cost of this system is relatively lower than 5% to 12%, and the energy utilization efficiency is higher. The heat pump power storage system based on heat pump and organic Rankine cycle is a power storage technology based on electric energy → thermal energy → electric energy, which has the advantages of not being restricted by geographical conditions, large storage capacity, high efficiency and long energy storage cycle.

[0020] 2. The water electrolysis hydrogen production device can receive and utilize the surplus electricity in the power grid. This surplus electricity is usually generated when the electricity demand is low. If it is not utilized, it may cause energy waste. By electrolyzing water to produce hydrogen, this surplus electricity is converted into hydrogen energy, realizing energy storage and reuse, and improving the overall energy utilization efficiency of the power grid.

[0021] 3. The first compressor is responsible for compressing the raw gas to a pressure range suitable for ammonia synthesis. The compressed gas has a higher energy density, which is conducive to full reaction in the ammonia synthesis reactor, thereby improving the efficiency of synthetic ammonia. The first expander is used to recover the high-pressure energy in the outlet gas of the ammonia synthesis reactor and convert it into mechanical energy or electrical energy, which can be used to drive other equipment or supply the power grid to achieve efficient use of energy.

[0022] 4. The second compressor compresses the low-temperature and low-pressure heat source gas into high-temperature and high-pressure gas, which improves the quality of the heat source. The high-temperature and high-pressure gas releases heat in the first heat exchanger and is used to heat the working medium to achieve thermal energy conversion.

[0023] 5. The first tank body, as a thermal energy storage unit, can store thermal energy from an external heat source or a heat pump system. Through the first outlet, the thermal energy can be transported to the third heat exchanger for further processing. Secondly, the heat storage process can be carried out during off-peak hours or low-cost hours, thereby optimizing energy utilization and cost-effectiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic diagram of a heat pump power storage system for coupling flue gas waste heat utilization and solid hydrogen production of ammonia provided by the present invention; Figure 2 A schematic diagram of a synthetic ammonia device in a heat pump power storage system coupled with flue gas waste heat utilization and solid hydrogen production of ammonia provided by the present invention; Figure 3 A flow chart of a heat pump power storage method for coupling flue gas waste heat utilization, carbon capture and solid hydrogen production to produce ammonia provided by the present invention; Among them: 1. Solar heater; 2. Ammonia synthesis reactor; 3. First compressor; 4. Water electrolysis hydrogen production device; 5. First expander; 6. First valve; 7. Second compressor; 8. First heat exchanger; 9. Second expander; 10. Throttle valve; 11. Second heat exchanger; 12. First tank; 13. Third heat exchanger; 14. Second tank; 15. Second valve; 16. Third valve; 17. Third expander; 18. Fourth heat exchanger; 19. Fourth expander; 20. First condenser; 21. Water pump; 22. Second condenser; 23. Gas separator; 24. CO2 absorption tower; 25. Absorbent regeneration tower; 26. Third compressor; 27. Fifth expander; 28. Ammonia synthesis reaction 1. the second inlet valve of the ammonia synthesis reactor; 29. ​​the first inlet valve of the ammonia synthesis reactor; 30. the first blower; 31. the first valve of the ammonia synthesis reactor; 32. the first spiral heat exchanger; 33. the second valve of the ammonia synthesis reactor; 34. the third valve of the ammonia synthesis reactor; 35. the second blower; 36. the fourth valve of the ammonia synthesis reactor; 37. the second spiral heat exchanger; 38. the fifth valve of the ammonia synthesis reactor; 39. the sixth valve of the ammonia synthesis reactor; 40. the seventh valve of the ammonia synthesis reactor; 41. the first mesh heat exchanger; 42. the third spiral heat exchanger; 43. the first outlet valve of the ammonia synthesis reactor; 44. the second mesh heat exchanger; 45. the third mesh heat exchanger; 46. the fourth mesh heat exchanger; 47. the fifth mesh heat exchanger. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0029] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0030] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] Traditional waste heat utilization technologies, such as waste heat boilers and heat exchangers, are not very efficient under these low temperature conditions, limiting the scope and efficiency of waste heat recovery. The application of these technologies often requires high initial investment and operation and maintenance costs. For many power generation companies, these costs may exceed the financial budget, resulting in these effective waste heat utilization technologies not being widely used.

[0032] Physical energy storage is currently the most suitable large-scale electricity storage method for peak-shaving, frequency regulation, valley filling and emergency backup of renewable energy power grids; pumped storage and compressed air energy storage are typical large-scale energy storage technologies based on electrical energy → mechanical energy → electrical energy, with high round-trip efficiency and maturity, but their flexible application is limited by geographical factors; and the heat pump energy storage system based on heat pump and organic Rankine cycle is an energy storage technology based on electrical energy → thermal energy → electrical energy, with the advantages of not being restricted by geographical conditions, large storage capacity, high efficiency and long energy storage cycle.

[0033] According to existing standards, hydrogen is positioned as a hazardous chemical and can only be produced in chemical parks, which increases transportation costs. Hydrogen is very active and has extremely poor stability. It is prone to combustion and explosion after leakage. Under high temperature and high pressure, hydrogen can even pass through very thick steel plates. Therefore, hydrogen storage and hydrogen energy transportation are major problems today.

[0034] In order to solve the above technical defects, the inventor provides a heat pump power storage system and method that couples flue gas waste heat utilization with solid hydrogen production of ammonia.

[0035] The present invention is further described in detail below in conjunction with the accompanying drawings: like Figure 1-Figure 2As shown, in a first aspect of an embodiment of the present invention, a heat pump power storage system coupling flue gas waste heat utilization and solid hydrogen production of ammonia is provided, comprising a solar heating device, a water electrolysis hydrogen production device 4, an ammonia synthesis device, a heat pump circulation device, a heat storage circulation device, an organic Rankine cycle and a carbon capture circulation device, wherein the solar heating device, the water electrolysis hydrogen production device 4, the ammonia synthesis device, the heat pump circulation device, the heat storage circulation device, the organic Rankine cycle and the carbon capture circulation device are sequentially connected; wherein the solar heating device is preferably a solar heater 1, which is used to heat the flue gas, the water electrolysis hydrogen production device 4 is used to prepare hydrogen and oxygen using the waste electricity of the power plant, and the heat pump circulation device is used to recover the heat of the flue gas. The heat released during the reaction with the synthetic ammonia unit is used to improve the quality of the low-level heat source through the electric-driven heat pump circulation device, and output high-temperature heat; the heat storage cycle is used to store the high-temperature heat output by the heat pump circulation device, and supply the high-temperature heat to the organic Rankine cycle and carbon capture cycle device when needed. The organic Rankine cycle converts the heat energy stored in the heat storage cycle device into electricity; the carbon capture cycle includes an adsorption process and a desorption process. The adsorption process is used to capture carbon dioxide in the low-temperature flue gas, and the desorption process is used to heat and regenerate the saturated adsorption material with the high-temperature heat obtained in the heat storage cycle, so as to achieve the regeneration of the adsorption material and produce high-purity carbon dioxide, which can be used as a raw material for production. In addition, the released carbon dioxide has a high heat content and can be compressed and then used as a turbine to generate electricity. During the application process, the system uses medium-temperature flue gas as a carbon source and heat source, and the surplus electricity of the power plant as a power source. The surplus electricity of the power plant is used to drive the compressor and prepare hydrogen. The medium-temperature flue gas is further heated as a heat source for the synthetic ammonia reaction, so that hydrogen and nitrogen are converted into ammonia, which solves the problem of difficult hydrogen storage. During the charging process, the waste heat of flue gas and the heat released by chemical reactions are recovered as low-level heat sources of the heat pump cycle. The heat pump cycle driven by the surplus electricity is upgraded and stored in a high-temperature storage tank. During the discharge process, the organic Rankine cycle is used to convert the stored heat energy into electricity, and the heat of the mixed gas generated by the synthetic ammonia reaction is further recovered through the regenerator. The desorption process of the carbon capture cycle is driven by the heat stored in the high-temperature storage tank. The whole process uses heat storage as an intermediate process, realizing low-cost, high-density and long-term storage of electric energy, effectively solving the problems encountered in energy transformation and the peak-shaving needs of the power grid; and the coupled carbon capture system uses the heat in the high-level storage tank to solve the problem of high carbon dioxide content in the exhaust flue gas. The round-trip efficiency of "electricity-heat-electricity" in this system is high, realizing the comprehensive utilization of electricity and heat, and the comprehensive energy utilization efficiency is high. Hydrogen is produced by electrolyzing water with surplus electricity from thermal power plants, and then hydrogen and cheap nitrogen are prepared into ammonia through the synthetic ammonia reaction. Hydrogen is stored and transported in the form of ammonia, solving the problem of difficult hydrogen storage. The cascade utilizes the heat of chemical reaction, which increases the temperature of the heat source by 17% to 33%. At the same time, the high-temperature and high-pressure ammonia generated by the reaction is used for turbine power generation, making full use of thermal energy.Finally, the high content of carbon dioxide in the flue gas of the thermal power plant is captured, and the heat in the high-temperature hot tank is used to regenerate the capture material, thereby achieving the separation of carbon dioxide and obtaining high-purity carbon dioxide.

[0036] like Figure 1 As shown, the water electrolysis hydrogen production device 4 is used to receive surplus power from the power grid, and electrolyze water to obtain hydrogen and oxygen through the surplus power from the power grid, wherein hydrogen participates in subsequent reactions, and oxygen is output as a by-product. The synthetic ammonia device includes an ammonia synthesis reactor 2, a first compressor 3 and a first expander 5. After hydrogen is mixed with nitrogen at a ratio slightly less than 1:3 through a pipeline, it enters the first compressor 3 from the inlet, and the outlet of the first compressor 3 is connected to the first inlet at the bottom of the ammonia synthesis reactor 2, and the first outlet of the ammonia synthesis reactor 2 is connected to the first expander 5. The outlet of the solar heater 1 is connected to the second inlet at the bottom of the ammonia synthesis reactor 2, and the second outlet of the ammonia synthesis reactor 2 is connected to the second heat exchanger 11; the first inlet of the ammonia synthesis reactor 2 is connected to the first outlet of the ammonia synthesis reactor 2 through the first spiral heat exchanger 32, the second spiral heat exchanger 37 and the third spiral heat exchanger 42; the second inlet of the ammonia synthesis reactor 2 passes through the preheating chamber, and the reaction chamber is connected to its second outlet. There is a third outlet and a third inlet inside the reaction chamber of the ammonia synthesis reactor 2; the third outlet of the ammonia synthesis reactor 2 is connected to the third inlet through the second heat exchanger 11.

[0037] The heat pump circulation device includes a second compressor 7, a first heat exchanger 8, a second expander 9, a throttle valve 10 and a second heat exchanger 11. The first and second inlets of the second heat exchanger 11 are respectively connected to the second outlet and the third outlet of the ammonia synthesis reactor 2, the first outlet of the second heat exchanger 11 is connected to the first inlet of the CO2 absorption tower 24, the second compressor 7 is connected to the third outlet of the second heat exchanger 11, and the second compressor 7 is also connected to the first inlet of the first heat exchanger 8; the first outlet of the first heat exchanger 8 is connected to the second expander 9, the second expander 9 is connected to the third inlet of the second heat exchanger 11 through the throttle valve 10, the first inlet of the second heat exchanger 11 is connected to the first outlet; the second inlet of the second heat exchanger 11 is connected to the second outlet. The heat storage cycle device includes a first heat exchanger 8, a first tank body 12, a third heat exchanger 13 and a second tank body 14. The second inlet of the first heat exchanger 8 is connected to the first expander 5 through the first valve 6, and the third outlet of the first heat exchanger 8 is connected to the first inlet of the first tank body 12; the first outlet of the first tank body 12 is connected to the first inlet of the third heat exchanger 13; the first outlet of the third heat exchanger 13 is connected to the second tank body 14; the second tank body 14 is connected to the third inlet of the first heat exchanger 8; the second outlet of the first heat exchanger 8 is connected to the second condenser 22; the first inlet of the first heat exchanger 8 is connected to the first outlet; the second outlet of the first heat exchanger 8 is connected to the second inlet; the third outlet of the first heat exchanger 8 is connected to the third inlet. The first inlet of the third heat exchanger 13 is connected to the first outlet.

[0038] The organic Rankine cycle includes a third heat exchanger 13, a third expander 17, a fourth heat exchanger 18, a fourth expander 19, a first condenser 20 and a water pump 21; the second inlet of the third heat exchanger 13 is connected to the first expander 5 through the second valve 15, the second outlet of the third heat exchanger 13 is connected to the second condenser 22, and the third outlet of the third heat exchanger 13 is connected to the third expander 17; the third expander 17 is connected to the first inlet of the fourth heat exchanger 18; the first outlet of the fourth heat exchanger 18 is connected to the fourth expander 19, and the fourth expander 19 is connected to the first condenser 2 0; the first condenser 20 is connected to the water pump 21; the water pump 21 is connected to the third inlet of the third heat exchanger 13; the second inlet of the fourth heat exchanger 18 is connected to the first expansion machine 5 through the third valve 16; the second outlet of the fourth heat exchanger 18 is connected to the second condenser 22, and the second condenser 22 is connected to the gas separator 23; the second inlet of the third heat exchanger 13 is connected to the second outlet; the third inlet of the third heat exchanger 13 is connected to the third outlet; the first inlet of the fourth heat exchanger 18 is connected to the first outlet; the second inlet of the fourth heat exchanger 18 is connected to the second outlet.

[0039] The carbon capture cycle device includes a CO2 absorption tower 24, an absorbent regeneration tower 25, a third compressor 26 and a fifth expander 27. The first outlet of the CO2 absorption tower 24 is connected to the first inlet; the second outlet of the CO2 absorption tower 24 is connected to the second inlet. The second outlet of the CO2 absorption tower 24 is connected to the first inlet of the absorbent regeneration tower 25; the second inlet of the CO2 absorption tower 24 is connected to the first outlet of the absorbent regeneration tower 25; the second inlet of the absorbent regeneration tower 25 is connected to the second outlet of the first tank body 12; the second outlet of the absorbent regeneration tower 25 is connected to the second inlet of the first tank body 12; the third compressor 26 is connected to the third outlet of the absorbent regeneration tower 25; and the fifth expander 27 is connected to the third compressor 26.

[0040] The second inlet of the ammonia synthesis reactor 2 is connected to the outlet of the solar heater 1 through the second inlet valve 28 of the ammonia synthesis reactor; the first inlet of the ammonia synthesis reactor 2 is connected to the outlet of the first compressor 3 through the first inlet valve 29 of the ammonia synthesis reactor; the first outlet of the ammonia synthesis reactor 2 is connected to the inlet of the first expander 5 through the first outlet valve 43 of the ammonia synthesis reactor; the second inlet valve 28 of the ammonia synthesis reactor is connected to the first spiral heat exchanger 32; the first spiral heat exchanger 32 is connected to the second spiral heat exchanger 37 through the third valve 34 of the ammonia synthesis reactor; the second spiral heat exchanger 37 is connected to the third spiral heat exchanger 42 through the sixth valve 39 of the ammonia synthesis reactor; the second spiral heat exchanger 37 is also ... The seventh valve 40 of the ammonia synthesis reactor is connected to the second outlet; the second inlet valve 28 of the ammonia synthesis reactor is connected to the first reaction chamber; the first reaction chamber is connected to the second reaction chamber through the second valve 33 of the ammonia synthesis reactor; the second reaction chamber is connected to the third reaction chamber through the fifth valve 38 of the ammonia synthesis reactor; the third reaction chamber is connected to the first outlet valve 43 of the ammonia synthesis reactor through the first outlet valve 43 of the ammonia synthesis reactor; the first reaction chamber is provided with a first blower 30, a first valve 31 of the ammonia synthesis reactor, a fourth mesh heat exchanger 46 and a fifth mesh heat exchanger 47; the inlet of the first blower 30 is connected to the first valve 31 of the ammonia synthesis reactor, located at the upper part of the first reaction chamber, and the outlet is located at the bottom of the first reaction chamber. The second reaction chamber is provided with a third mesh heat exchanger 45 and a first mesh heat exchanger 41; the outlet of the second blower 35 is located at the bottom of the second reaction chamber. The third reaction chamber is provided with a second mesh heat exchanger 44; the inlet of the second blower 35 is connected to the upper part of the third reaction chamber through the fourth valve 36 of the ammonia synthesis reactor; the third mesh heat exchanger 45 is connected to the fourth mesh heat exchanger 46; the second mesh heat exchanger 44 is connected to the fifth mesh heat exchanger 47; the bottom of the second reaction chamber is connected to the top of the third reaction chamber through the second blower 35 and the fourth valve 36 of the ammonia synthesis reactor. The absorption medium of the CO2 absorption tower 24 absorbs carbon dioxide at 100 to 200 degrees and releases carbon dioxide at 400 to 500 degrees. The material can be selected from MgO / POL-PPH3 adsorbent or CdO-MgO adsorbent.

[0041] The inlet flue gas of the ammonia synthesis reactor 2 preheats the mixed gas in the chamber through a spiral pipe. There is a gas circulation device in the preheating chamber. At least two reaction chambers are set. All reaction chambers before the last reaction chamber must be equipped with a heat transfer device. This scheme takes two reaction chambers as an example. The heat transfer device corresponds to the third outlet and the third inlet of the ammonia synthesis reactor 2; when the previous reaction chamber reaches the reaction limit of the current temperature, the valve between the reaction chambers is opened to allow the mixed gas to enter the next reaction chamber; the catalyst in the reaction chamber is attached to the flue gas pipeline using a mesh structure; the catalyst can be selected from an iron catalyst medium, requiring 100-300bar, or a sodium alloy, which can react under normal pressure. The heat transfer device is a mesh structure, containing a heat-absorbing medium, located in the reaction chamber. When the reaction temperature is measured to be above 400 degrees, the valve is opened to allow the coolant to flow and absorb heat to maintain a certain temperature.

[0042] In the second aspect, this embodiment provides a heat pump power storage method that couples flue gas waste heat utilization carbon capture and solid hydrogen production of ammonia, such as Figure 3 As shown, including: S101, heating the medium-temperature flue gas to a medium-high temperature state, using a water electrolysis hydrogen production device to electrolyze water to obtain hydrogen and oxygen; illustratively, the medium-temperature flue gas is heated to a medium-high temperature state by a solar heater 1, and in the water electrolysis hydrogen production device 4, the water electrolysis hydrogen production device 4 electrolyzes water to obtain hydrogen and oxygen, wherein oxygen is output as a by-product, and hydrogen and exogenous nitrogen are compressed to a high-pressure state by a first compressor 3 and enter the ammonia synthesis reactor 2.

[0043] S102, transport the heated flue gas in the medium-high temperature state to the synthetic ammonia device, so that the medium-high temperature flue gas preheats nitrogen, hydrogen and the mixed gas of nitrogen and hydrogen to obtain a low-temperature and low-pressure mixed gas; illustratively, the medium-high temperature flue gas preheats the nitrogen and hydrogen mixed gas, and all three are in the medium-high temperature state, and then enters the ammonia synthesis reactor 2. Due to the exothermic reaction, the product ammonia and the original medium-high temperature flue gas are both in the high temperature state. Because the reaction is reversible, the product ammonia contains nitrogen and hydrogen. In order to make the ammonia output high enough, the method of two reactions is adopted, and the heat recovery pipe is used in the middle to exchange heat and cool down with the second heat exchanger 11. The high-temperature and high-pressure product mixed gas enters the first expander 5, and after power generation, it becomes a high-temperature and low-pressure product mixed gas. The product mixed gas first enters the fourth heat exchanger 18 through the third valve 16 for heat exchange with the organic Rankine cycle working fluid, and then can be selectively passed into or successively enters the first heat exchanger 8 through the first valve 6 for heat exchange with the heat storage cycle working fluid according to the temperature, or enters the third heat exchanger 13 through the second valve 15 for heat exchange with the organic Rankine cycle working fluid, and finally obtains a low-temperature and low-pressure product mixed gas. This product mixed gas passes through the second condenser 22 and the gas separator 23 to obtain product ammonia and raw nitrogen and hydrogen, of which nitrogen and hydrogen are returned to the first compressor 3 for reuse.

[0044] S103, subjecting the low-temperature and low-pressure mixed gas to a catalytic reaction, and using a heat pump circulation device to exchange heat, and then converting it into a low-temperature and low-pressure working fluid; illustratively, the high-pressure hydrogen-nitrogen mixed gas enters the first reaction chamber through the first inlet valve 29 of the ammonia synthesis reactor. The medium-high temperature flue gas enters the first spiral heat exchanger 32 through the second inlet valve 28 of the ammonia synthesis reactor. Here, the high-pressure hydrogen-nitrogen mixed gas exchanges heat with the medium-high temperature flue gas to become a medium-high temperature and high-pressure hydrogen-nitrogen mixed gas. Open the first blower 30 and the first valve 31 of the ammonia synthesis reactor to circulate the upper high-temperature gas and the lower low-temperature gas to fully heat. After heating to a certain degree, open the second valve 33 of the ammonia synthesis reactor and the third valve 34 of the ammonia synthesis reactor, the medium-high temperature flue gas enters the second spiral heat exchanger 37, and the medium-high temperature and high-pressure hydrogen-nitrogen mixed gas enters the second reaction chamber. At this time, the first catalytic reaction is carried out, and the heat released is absorbed by the first mesh heat exchanger 41 to keep the reaction temperature stable. The surplus heat is absorbed by the third mesh heat exchanger 45 and enters the first reaction chamber for heat exchange. During this process, the medium and high temperature flue gas absorbs heat and becomes high temperature flue gas, and some hydrogen and nitrogen are not fully reacted. The gas in the reaction chamber is a mixed gas of nitrogen, hydrogen and ammonia. During the reaction process, the seventh valve 40 of the ammonia synthesis reactor can be opened according to the temperature of the flue gas to discharge the high temperature flue gas, or the sixth valve 39 of the ammonia synthesis reactor can be opened to allow the high temperature flue gas to enter the third spiral heat exchanger 42. After a period of reaction, the fifth valve 38 of the ammonia synthesis reactor is opened, and the mixed gas in the second reaction chamber enters the third reaction chamber. The heat of the mixed gas is further absorbed by the second mesh heat exchanger 44 here, and the reaction is more fully reacted. The temperature is maintained by the high temperature flue gas in the third spiral heat exchanger 42. In order to make the reaction more complete, the second blower 35 and the fourth valve 36 of the ammonia synthesis reactor are opened so that the mixed gas can circulate between the second reaction chamber and the third reaction chamber; after the reaction is complete, the first outlet valve 43 of the ammonia synthesis reactor is opened to obtain a product mixed gas.

[0045] The high-temperature flue gas enters the second heat exchanger 11 and exchanges heat with the working fluid in the heat pump cycle to become medium-low temperature flue gas. This flue gas enters the CO2 absorption tower 24, and the circulating working fluid becomes medium-high temperature. The circulating working fluid is compressed to a high-temperature and high-pressure state by the second compressor 7, and then exchanges heat with the working fluid in the heat storage cycle in the first heat exchanger 8. The heat pump circulating working fluid becomes low-temperature and high-pressure, and then enters the second expander 9 to generate electricity, and becomes a low-temperature and low-pressure working fluid after passing through the throttle valve 10.

[0046] S104, through the organic Rankine cycle, the low-temperature and low-pressure working fluid is converted into a low-temperature and medium-pressure organic Rankine cycle working fluid; illustratively, the high-temperature heat storage working fluid that has exchanged heat in the first heat exchanger 8 enters the first tank 12, and when necessary, exchanges heat with the organic Rankine cycle working fluid in the third heat exchanger 13, and the heat storage working fluid changes to low temperature and enters the second tank 14. In the organic Rankine cycle, the high-temperature and high-pressure organic Rankine cycle working fluid after heat exchange passes through the third expander 17 to become a medium-temperature and low-pressure organic Rankine cycle working fluid, and then exchanges heat with the high-temperature product mixed gas in the fourth heat exchanger 18 to become a high-temperature and high-pressure organic Rankine cycle working fluid, and the product mixed gas changes to medium and low temperature. The organic Rankine cycle working fluid passes through the fourth expander 19 to become a medium-temperature and low-pressure organic Rankine cycle working fluid, and passes through the first condenser 20 and the water pump 21 to become a low-temperature and medium-pressure organic Rankine cycle working fluid.

[0047] S105, converting the low-temperature flue gas into low-temperature and low-pressure carbon dioxide through the carbon capture circulation device, and discharging it as a product. For example, in the carbon capture subsystem, the low-temperature flue gas is discharged at the bottom of the CO2 absorption tower 24, and after adsorption, it is converted into flue gas without carbon dioxide and discharged. The absorption medium enriched with carbon dioxide exchanges heat with the high-temperature heat storage medium in the first tank 12 in the absorbent regeneration tower 25. After releasing carbon dioxide, the absorption medium returns to the CO2 absorption tower 24. The medium-temperature carbon dioxide is compressed by the third compressor 26 to become medium-temperature and high-pressure carbon dioxide, and enters the fifth expander 27 to become low-temperature and low-pressure carbon dioxide, and is discharged as a product.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit its protection scope. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that after reading the present invention, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the protection scope of the pending claims of the invention.

Claims

1. A heat pump power storage system that couples flue gas waste heat utilization with solid hydrogen production of ammonia, characterized in that: include: A solar heating device, a water electrolysis hydrogen production device (4), an ammonia synthesis device, a heat pump circulation device, a heat storage circulation device, an organic Rankine cycle and a carbon capture circulation device, wherein the solar heating device, the water electrolysis hydrogen production device (4), the ammonia synthesis device, the heat pump circulation device, the heat storage circulation device, the organic Rankine cycle and the carbon capture circulation device are connected in sequence; The solar heating device is used to heat the flue gas, the water electrolysis hydrogen production device (4) is used to use the surplus electricity of the power plant to produce hydrogen and oxygen, and the heat pump circulation device is used to recover the heat of the flue gas and the heat released during the reaction of the ammonia synthesis device, and to improve the quality of the low-level heat source through electric drive to output high-temperature heat; The heat storage cycle is used to store the high-temperature heat and supply the high-temperature heat to the organic Rankine cycle and the carbon capture cycle device.

2. The system according to claim 1, characterized in that The water electrolysis hydrogen production device (4) is used to receive surplus electricity from a power grid, and to electrolyze water using the surplus electricity from the power grid to obtain hydrogen and oxygen, with the oxygen being output as a by-product.

3. The system according to claim 1, characterized in that The ammonia synthesis device comprises an ammonia synthesis reactor (2), a first compressor (3) and a first expander (5), wherein a first inlet at the bottom of the ammonia synthesis reactor (2) is connected to the first compressor (3), and a first outlet of the ammonia synthesis reactor (2) is connected to the first expander (5).

4. The system according to claim 1, characterized in that The heat pump circulation device comprises a second compressor (7), a first heat exchanger (8), a second expander (9), a throttle valve (10) and a second heat exchanger (11), wherein the second compressor (7) is connected to a third outlet of the second heat exchanger (11), and the second compressor (7) is also connected to a first inlet of the first heat exchanger (8); The first outlet of the first heat exchanger (8) is connected to the second expander (9), and the second expander (9) is connected to the third inlet of the second heat exchanger (11) via the throttle valve (10).

5. The system according to claim 1, characterized in that The heat storage cycle device comprises a first tank body (12), a third heat exchanger (13) and a second tank body (14); a first outlet of the first tank body (12) is connected to a first inlet of the third heat exchanger (13), and a first outlet of the third heat exchanger (13) is connected to the second tank body (14).

6. The system according to claim 1, characterized in that The organic Rankine cycle comprises a third heat exchanger (13), a third expander (17), a fourth heat exchanger (18), a fourth expander (19), a first condenser (20) and a water pump (21); The third outlet of the third heat exchanger (13) is connected to the third expander (17), the third expander (17) is connected to the first inlet of the fourth heat exchanger (18), and the first outlet of the fourth heat exchanger (18) is connected to the fourth expander (19); The fourth expander (19) is connected to the first condenser (20), and the first condenser (20) is connected to the water pump (21).

7. The system according to claim 6, characterized in that The water pump (21) is connected to the third inlet of the third heat exchanger (13), and the second outlet of the fourth heat exchanger (18) is connected to the second condenser (22).

8. The system according to claim 1, characterized in that The carbon capture cycle device comprises a CO2 absorption tower (24), an absorbent regeneration tower (25), a third compressor (26) and a fifth expander (27), wherein the second outlet of the CO2 absorption tower (24) is connected to the first inlet of the absorbent regeneration tower (25), and the second inlet of the CO2 absorption tower (24) is connected to the first outlet of the absorbent regeneration tower (25).

9. The system according to claim 8, characterized in that The third outlet of the absorbent regeneration tower (25) is connected to the third compressor (26), and the fifth expander (27) is also connected to the third compressor (26).

10. A heat pump power storage method that couples flue gas waste heat utilization, carbon capture and solid hydrogen production to ammonia, characterized in that: include: The medium-temperature flue gas is heated to a medium-high temperature state, and water is electrolyzed by a water electrolysis hydrogen production device to obtain hydrogen and oxygen; The heated flue gas in a medium-high temperature state is transported to a synthetic ammonia device, so that the medium-high temperature flue gas preheats nitrogen, hydrogen and a mixed gas of nitrogen and hydrogen to obtain a low-temperature and low-pressure mixed gas; The low-temperature and low-pressure mixed gas is subjected to a catalytic reaction and converted into a low-temperature and low-pressure working fluid after heat exchange using a heat pump circulation device; By means of an organic Rankine cycle, the low-temperature and low-pressure working fluid is converted into a low-temperature and medium-pressure organic Rankine cycle working fluid; The low-temperature flue gas is converted into low-temperature and low-pressure carbon dioxide through a carbon capture circulation device and discharged as a product.

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