A polytropic co-production carbon dioxide power cycle system and method thereof

Abstract

The present application belongs to the technical field of comprehensive energy utilization, and relates to a multi-energy co-production carbon dioxide power cycle system and method thereof, comprising a gas storage bin, a first compressor, a first cooler, a liquid storage tank, a first turbine and a post-preheater, a hot water supply unit, a waste heat recovery unit and a cold energy recovery unit. The present application supplies hot water through the hot water supply unit to absorb the heat generated by multi-stage compression of carbon dioxide to obtain steam to supply steam to users, and absorbs and stores waste heat of the system through cooperation of the waste heat recovery unit and the hot water supply unit to heat carbon dioxide after expansion and work, and recovers cold energy in the carbon dioxide after expansion and work through the cold energy recovery unit to supply cold water or make ice to users, so that waste heat and cold energy of the power cycle process can be recovered, and steam and cold energy including electric energy are output, which not only reduces system energy consumption, but also improves energy utilization efficiency of the system.

Description

Technical Field

[0001] This invention belongs to the field of integrated energy utilization technology, and relates to a carbon dioxide power cycle system and method for multi-energy cogeneration. Background Technology

[0002] A carbon dioxide power cycle is a power system that uses carbon dioxide as the working fluid and converts thermal energy into mechanical or electrical energy through a thermodynamic cycle process of absorbing heat, expanding to do work, releasing waste heat, and compressing and regenerating. Its core feature is the utilization of the physical properties of carbon dioxide at specific temperatures and pressures, especially its excellent heat transfer and flow properties in the supercritical state, to achieve efficient energy conversion. It is one of the important alternatives and upgrade technologies for traditional steam power cycles.

[0003] Currently, a traditional carbon dioxide power cycle consists of a gas storage chamber, multiple compressors, multiple coolers, a high-pressure tank, multiple turbines, multiple heaters, and a motor connected in sequence. During the power cycle, the carbon dioxide in the gas storage chamber enters multiple compressors in sequence, consuming electrical energy to drive multiple compressors to perform multi-stage compression. After each compression, the carbon dioxide enters the cooler for cooling, and finally, the room-temperature, high-pressure carbon dioxide enters the high-pressure tank for storage. The carbon dioxide in the high-pressure tank enters multiple turbines in sequence to expand and do work, and the kinetic energy generated drives the generator to generate electricity. After each expansion and work, the carbon dioxide enters the heater for heating, and finally, the carbon dioxide returns to its initial state before entering the gas storage chamber for storage.

[0004] However, the traditional carbon dioxide power cycle has a relatively simple production form, usually relying mainly on electricity output, which leads to a lot of energy being wasted during the power cycle process. This not only increases the system's energy consumption but also reduces the system's energy utilization efficiency. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-energy cogeneration carbon dioxide power cycle system and method, which can recover and utilize the waste heat inside the system during the power cycle process, and can output multiple energy sources including electrical energy, thereby not only reducing system energy consumption, but also improving the system's energy utilization efficiency.

[0006] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0007] A multi-energy cogeneration carbon dioxide power cycle system includes, in sequence, a gas storage chamber, a first compressor, a first cooler, a liquid storage tank, a first turbine and a post-preheater, and further includes:

[0008] The hot water supply unit is connected to the first cooler and the post-preheater respectively. It is used to send hot water into the first cooler to absorb heat and obtain steam for supply to users, and to send hot water into the post-preheater to provide heat for the expanded carbon dioxide.

[0009] The waste heat recovery unit includes an aftercooler and a hot water tank. The first inlet of the aftercooler is connected to the first cooler, the first outlet of the aftercooler is connected to the liquid storage tank, the second inlet of the aftercooler is connected to the hot water supply unit, and the second outlet of the aftercooler is connected to the inlet of the hot water tank. It is used to absorb the waste heat of compressed carbon dioxide with hot water and store it in the hot water tank, and use the stored hot water to raise the carbon dioxide temperature at the first turbine inlet.

[0010] The cold energy recovery unit includes a first refrigerator, which is located between the first turbine and the post-preheater. The first refrigerator is used to introduce cooling water to absorb the cold energy in the carbon dioxide after expansion and work, so as to supply cold water or make ice to users.

[0011] The invention is further characterized by:

[0012] The hot water supply unit includes a fourth compressor, a first condenser, a fourth turbine, and a first evaporator connected in sequence. The fourth compressor is used to compress carbon dioxide. The first inlet of the first condenser is used to introduce cooling water to absorb the heat in the compressed carbon dioxide. The first outlet of the first condenser is connected to the first cooler. The fourth turbine is used to expand the compressed carbon dioxide to generate mechanical energy to drive the fourth compressor. The first inlet of the first evaporator is used to introduce cooling water to absorb the coldness of the expanded carbon dioxide to supply cold water or make ice to users.

[0013] The first outlet of the first condenser is equipped with a booster pump. The inlet of the booster pump is connected to the first outlet of the first condenser, and the outlet of the booster pump is connected to the first cooler.

[0014] A first preheater is installed between the gas storage chamber and the first compressor. The first preheater is used to preheat carbon dioxide using hot water provided by the first condenser.

[0015] The first cooler is connected to the liquid storage tank in sequence by a second compressor, a second cooler, a third compressor, and a third cooler. The first refrigerator is connected to the preheater in sequence by a second preheater, a first heater, a second turbine, a second refrigerator, a third preheater, a second heater, a third turbine, and a third refrigerator. The first inlets of the second cooler and the third cooler are respectively connected to the outlet of the booster pump. The first inlets of the second preheater and the third preheater are respectively connected to the first outlet of the first condenser. The first inlets of the first heater and the second heater are respectively connected to the outlet of the hot water tank.

[0016] The liquid storage tank is equipped with a second evaporator at its outlet. The first inlet of the second evaporator is connected to the outlet of the liquid storage tank. The first outlet of the second evaporator is equipped with a third heater. The second inlet of the second evaporator is connected to the first outlet of the first condenser. The first inlet of the third heater is connected to the first outlet of the second evaporator. The first outlet of the third heater is connected to the inlet of the first turbine. The second inlet of the third heater is connected to the outlet of the hot water tank.

[0017] A second condenser is installed between the aftercooler and the liquid storage tank. The first inlet of the second condenser is connected to the first outlet of the aftercooler, and the first outlet of the second condenser is connected to the inlet of the liquid storage tank. The second inlet of the second condenser is used to introduce cooling water.

[0018] A multi-energy cogeneration carbon dioxide power cycle method includes the following steps:

[0019] The hot water supply unit generates hot water, which is then transported to the outlet of the gas storage tank to preheat ambient temperature and atmospheric pressure carbon dioxide to obtain medium temperature and ambient pressure carbon dioxide. The medium temperature and ambient pressure carbon dioxide sequentially enters the first compressor and the first cooler for compression and cooling to obtain sub-high temperature and high pressure carbon dioxide. The sub-high temperature and high pressure carbon dioxide is then cooled by heat exchange with the hot water from the hot water supply unit to obtain medium temperature and high pressure carbon dioxide. The heated hot water enters the hot water tank for storage. After cooling, the medium temperature and high pressure carbon dioxide becomes liquid low temperature and high pressure carbon dioxide and enters the liquid storage tank for storage. At the same time, the hot water generated by the hot water supply unit enters the booster pump for pressurization and then enters the first cooler for heat exchange and heating to obtain steam.

[0020] Low-temperature, high-pressure carbon dioxide in the storage tank sequentially enters the second evaporator, the third heater, and the first turbine for two heating cycles. After expansion, it drives the generator to generate electricity. The low-temperature, high-pressure carbon dioxide is transformed into ultra-low-temperature, normal-pressure carbon dioxide. The ultra-low-temperature, normal-pressure carbon dioxide then enters the third refrigeration unit and the post-preheater for cooling and heating, transforming it into normal-temperature, normal-pressure carbon dioxide before being stored in the gas storage chamber. Simultaneously, cooling water enters the first refrigeration unit to absorb cold energy, supplying cold water to users or making ice. Hot water from the hot water supply unit enters the second evaporator and the post-preheater for heat exchange and cooling before being discharged. Hot water from the hot water tank enters the third heater for heat exchange and cooling before being discharged.

[0021] The specific steps involved in generating hot water using the hot water supply unit are as follows:

[0022] Gaseous, low-temperature, medium-pressure carbon dioxide enters the fourth compressor and is compressed to obtain medium-temperature, high-pressure carbon dioxide. The medium-temperature, high-pressure carbon dioxide enters the first condenser and exchanges heat with cooling water, turning the cooling water into hot water for supply. The medium-temperature, high-pressure carbon dioxide then becomes liquid, at room temperature, high-pressure carbon dioxide. The liquid, at room temperature, high-pressure carbon dioxide enters the fourth turbine, expands, and generates mechanical energy to drive the fourth compressor. The room-temperature, high-pressure carbon dioxide then becomes liquid, low-temperature, medium-pressure carbon dioxide. The liquid, low-temperature, medium-pressure carbon dioxide enters the first evaporator and exchanges heat with cooling water. The cooling water absorbs the cooling energy and supplies chilled water or ice to users. The liquid, low-temperature, medium-pressure carbon dioxide then becomes gaseous, low-temperature, medium-pressure carbon dioxide and enters the fourth compressor for circulation.

[0023] The temperatures of the medium-temperature, atmospheric-pressure carbon dioxide are 35℃~45℃ and the pressure is 0.101MPa; the temperatures of the sub-high-temperature, high-pressure carbon dioxide are 80℃~145℃ and the pressure is 6.9MPa~7.0MPa; the temperatures of the medium-temperature, high-pressure carbon dioxide are 45℃~55℃ and the pressure is 6MPa~7MPa; the temperatures of the liquid low-temperature, high-pressure carbon dioxide are -5℃~5℃ and the pressure is 3MPa~4MPa; the temperatures of the ultra-low-temperature, atmospheric-pressure carbon dioxide are -10℃~0℃ and the pressure is 0.101MPa; the temperatures of the gaseous low-temperature, medium-pressure carbon dioxide are -5℃~5℃ and the pressure is 3MPa~4MPa; the temperatures of the medium-temperature, high-pressure carbon dioxide are 45℃~55℃ and the pressure is 6MPa~7MPa; the temperatures of the liquid ambient-temperature, high-pressure carbon dioxide are 15℃~25℃ and the pressure is 6MPa~7MPa; and the temperatures of the liquid low-temperature, medium-pressure carbon dioxide are -5℃~5℃ and the pressure is 3MPa~4MPa.

[0024] The carbon dioxide power cycle system and method for multi-energy co-production of the present invention have the following advantages:

[0025] This invention utilizes a hot water supply unit to absorb heat from carbon dioxide through multi-stage compression to generate steam, which is then supplied to users. A waste heat recovery unit, in conjunction with the hot water supply unit, absorbs and stores system waste heat to heat the expanded carbon dioxide. A cold energy recovery unit then recovers the cold energy from the expanded carbon dioxide to supply users with chilled water or make ice. This process recovers waste heat and cold energy from the power cycle and outputs steam and cold energy, including electrical energy, thus reducing system energy consumption and improving system energy efficiency. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the first-stage compression structure of the present invention.

[0027] Figure 2 This is a schematic diagram of the hot water supply unit structure of the present invention.

[0028] Figure 3 This is a schematic diagram of the process of the present invention.

[0029] Figure 4 This is a schematic diagram of the three-stage compression structure of the present invention.

[0030] Figure label:

[0031] 1. First compressor; 2. First cooler; 3. Second compressor; 4. Second cooler; 5. Third compressor; 6. Third cooler; 7. Gas storage tank; 8. Liquid storage tank; 9. First turbine; 10. First heater; 11. Second turbine; 12. Second heater; 13. Third turbine; 14. Fourth compressor; 15. First condenser; 16. Fourth turbine; 17. First evaporator; 18. Aftercooler; 19. Hot water tank; 20. First refrigerator; 21. Second refrigerator; 22. Third refrigerator; 23. Booster pump; 24. First preheater; 25. Second evaporator; 26. Third heater; 27. Second preheater; 28. Third preheater; 29. ​​Afterheater; 30. Second condenser; 31. First control valve; 32. Second control valve; 33. Third control valve; 34. Fourth control valve. Detailed Implementation

[0032] The technical solutions of the present invention will now be described clearly and in detail with reference to the accompanying drawings. In the description of the embodiments of the present invention, unless otherwise stated, " / " indicates "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Furthermore, in the description of the embodiments of the present invention, "multiple" refers to two or more. The terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0033] Example 1

[0034] like Figure 1As shown, the present invention provides a multi-energy cogeneration carbon dioxide power cycle system, comprising a gas storage tank 7, a first compressor 1, a first cooler 2, a liquid storage tank 8, a first turbine 9, and a post-preheater 29 connected in sequence. It also includes a hot water supply unit, a waste heat recovery unit, and a cooling energy recovery unit. The hot water supply unit is connected to the first cooler 2 and the post-preheater 29, respectively, for supplying hot water to the first cooler 2 to absorb heat and obtain steam for supply to users, and for supplying hot water to the post-preheater 29 to provide heat for the expanded carbon dioxide. The waste heat recovery unit includes a post-cooler 18 and a hot water tank 19. The first inlet of the post-cooler 18 is connected to the first... A cooler 2 is connected, the first outlet of the aftercooler 18 is connected to the liquid storage tank 8, the second inlet of the aftercooler 18 is connected to the hot water supply unit, and the second outlet of the aftercooler 18 is connected to the inlet of the hot water tank 19. It is used to absorb the waste heat of compressed carbon dioxide with hot water and store it in the hot water tank 19, and use the stored hot water to raise the temperature of carbon dioxide at the inlet of the first turbine 9. The cold energy recovery unit includes a first cooler 20, which is located between the first turbine 9 and the afterheater 29. The first cooler 20 is used to introduce cooling water to absorb the cold energy in the carbon dioxide after expansion and work, so as to supply cold water or make ice to users.

[0035] like Figure 2 As shown, the hot water supply unit includes a fourth compressor 14, a first condenser 15, a fourth turbine 16, and a first evaporator 17 connected in sequence. The fourth compressor 14 is used to compress carbon dioxide. The first inlet of the first condenser 15 is used to introduce cooling water to absorb the heat in the compressed carbon dioxide. The first outlet of the first condenser 15 is connected to the first cooler 2. The fourth turbine 16 is used to expand the compressed carbon dioxide to generate mechanical energy to drive the fourth compressor 14. The first inlet of the first evaporator 17 is used to introduce cooling water to absorb the coldness of the expanded carbon dioxide to supply cold water or make ice to the user.

[0036] like Figure 1 As shown, a booster pump 23 is provided at the first outlet of the first condenser 15. The inlet of the booster pump 23 is connected to the first outlet of the first condenser 15, and the outlet of the booster pump 23 is connected to the first cooler 2, the second cooler 4, and the third cooler 6, respectively.

[0037] like Figure 1 As shown, a first preheater 24 is provided between the gas storage chamber 7 and the first compressor 1. The first inlet of the first preheater 24 is connected to the outlet of the gas storage chamber 7, the first outlet of the first preheater 24 is connected to the inlet of the first compressor 1, the second inlet of the first preheater 24 is connected to the first outlet of the first condenser 15, and the second outlet of the first preheater 24 is connected to a water storage tank. The first preheater 24 is used to preheat carbon dioxide using the hot water provided by the first condenser 15.

[0038] like Figure 1 As shown, a second condenser 30 is provided between the aftercooler 18 and the liquid storage tank 8. The first inlet of the second condenser 30 is connected to the first outlet of the aftercooler 18, the first outlet of the second condenser 30 is connected to the inlet of the liquid storage tank 8, the second inlet of the second condenser 30 is used to introduce cooling water, and the second outlet of the second condenser 30 is connected to the water storage tank.

[0039] like Figure 3 As shown, the present invention uses the above-described system for first-stage compression and first-stage turbine operation, as detailed below:

[0040] A multi-energy cogeneration carbon dioxide power cycle method includes the following steps:

[0041] The hot water supply unit generates hot water, which is then transported to the outlet of the gas storage chamber 7 to preheat ambient temperature and atmospheric pressure carbon dioxide to obtain medium temperature and ambient pressure carbon dioxide. The medium temperature and ambient pressure carbon dioxide sequentially enters the first compressor 1 and the first cooler 2 for compression and cooling to obtain sub-high temperature and high pressure carbon dioxide. The sub-high temperature and high pressure carbon dioxide is then cooled by heat exchange with the hot water from the hot water supply unit in the aftercooler 18 to obtain medium temperature and high pressure carbon dioxide. The heated hot water enters the hot water tank 19 for storage. After cooling, the medium temperature and high pressure carbon dioxide becomes liquid low temperature and high pressure carbon dioxide and enters the liquid storage tank 8 for storage. At the same time, the hot water generated by the hot water supply unit enters the booster pump 23 for pressurization and then enters the first cooler 2 for heat exchange and heating to obtain steam.

[0042] Low-temperature, high-pressure carbon dioxide in storage tank 8 sequentially enters the second evaporator 25, the third heater 26, and the first turbine 9 for two heating cycles. After expansion, it drives the generator to generate electricity. The low-temperature, high-pressure carbon dioxide becomes ultra-low-temperature, normal-pressure carbon dioxide. The ultra-low-temperature, normal-pressure carbon dioxide enters the third refrigerator 22 and the post-preheater 29 for cooling and heating, and then becomes normal-temperature, normal-pressure carbon dioxide, which is stored in the gas storage chamber 7. At the same time, cooling water enters the first refrigerator 20 to absorb cold energy and supply cold water or ice to users. Hot water from the hot water supply unit enters the second evaporator 25 and the post-preheater 29 for heat exchange and cooling before being discharged. Hot water from the hot water tank 19 enters the third heater 26 for heat exchange and cooling before being discharged.

[0043] In summary, this invention uses a hot water supply unit to absorb heat from carbon dioxide through multi-stage compression to generate steam, which is then supplied to users. Furthermore, a waste heat recovery unit, in conjunction with the hot water supply unit, absorbs and stores system waste heat to heat the carbon dioxide after it expands and performs work. Finally, a cold energy recovery unit recovers the cold energy from the expanded carbon dioxide to supply users with chilled water or make ice. This allows for the recovery of waste heat and cold energy from the power cycle process, and the output of steam and cold energy, including electrical energy. This not only reduces system energy consumption but also improves the system's energy efficiency.

[0044] Example 2

[0045] To optimize energy utilization efficiency, this invention also provides a three-stage compression and a three-stage turbine, as detailed below:

[0046] like Figure 4 As shown, a second compressor 3, a second cooler 4, a third compressor 5, and a third cooler 6 are sequentially connected between the first cooler 2 and the liquid storage tank 8. A second preheater 27, a first heater 10, a second turbine 11, a second cooler 21, a third preheater 28, a second heater 12, a third turbine 13, and a third cooler 22 are sequentially connected between the first refrigerator 20 and the post-preheater 29. The first inlets of the second cooler 4 and the third cooler 6 are respectively connected to the outlet of the booster pump 23. The first inlets of the second preheater 27 and the third preheater 28 are respectively connected to the first outlet of the first condenser 15. The first inlets of the first heater 10 and the second heater 12 are respectively connected to the outlet of the hot water tank 19.

[0047] like Figure 4 As shown, a second evaporator 25 is provided at the outlet of the liquid storage tank 8. The first inlet of the second evaporator 25 is connected to the outlet of the liquid storage tank 8. A third heater 26 is provided at the first outlet of the second evaporator 25. The second inlet of the second evaporator 25 is connected to the first outlet of the first condenser 15. The second outlet of the second evaporator 25 is connected to the water storage tank. The first inlet of the third heater 26 is connected to the first outlet of the second evaporator 25. The first outlet of the third heater 26 is connected to the inlet of the first turbine 9. The second inlet of the third heater 26 is connected to the outlet of the hot water tank 19. The outlet of the third heater 26 is connected to the water storage tank.

[0048] like Figure 1 , Figure 2 , Figure 4As shown, for ease of understanding, the first outlet of the first condenser 15 is labeled B, and the inlet of the booster pump 23, the second inlet of the first preheater 24, the second inlet of the aftercooler 18, the second inlet of the second evaporator 25, the second inlet of the second preheater 27, the second inlet of the third preheater 28, and the second inlet of the afterheater 29 are labeled A respectively. This allows the first outlet B of the first condenser 15 to be connected to the inlet A of the booster pump 23, the second inlet A of the first preheater 24, the second inlet A of the aftercooler 18, the second inlet A of the second evaporator 25, the second inlet A of the second preheater 27, the second inlet A of the third preheater 28, and the second inlet A of the afterheater 29, respectively. This facilitates the introduction of hot water from the first condenser 15 through the first outlet B into the inlet A of the booster pump 23, the second inlet A of the first preheater 24, the second inlet A of the aftercooler 18, the second inlet A of the second evaporator 25, the second inlet A of the second preheater 27, the second inlet A of the third preheater 28, and the second inlet A of the afterheater 29.

[0049] like Figure 1 , Figure 2 , Figure 4 As shown, the inlet of the fourth compressor 14 is equipped with a first control valve 31, the outlet of the gas storage chamber 7 is equipped with a second control valve 32, the outlet of the liquid storage tank 8 is equipped with a third control valve 33, and the outlet of the hot water tank 19 is equipped with a fourth control valve 34.

[0050] This invention employs the above-described system for first-stage compression and first-stage turbine operation, as detailed below:

[0051] A multi-energy cogeneration carbon dioxide power cycle method includes the following steps:

[0052] The hot water supply unit generates hot water, which is then transported to the outlet of the gas storage chamber 7 to preheat ambient temperature and atmospheric pressure carbon dioxide to obtain medium temperature and ambient pressure carbon dioxide. The medium temperature and ambient pressure carbon dioxide sequentially enters the first compressor 1, the first cooler 2, the second compressor 3, the second cooler 4, the third compressor 5, and the third cooler 6 for three-stage compression and three-stage cooling to obtain sub-high temperature and high pressure carbon dioxide. The sub-high temperature and high pressure carbon dioxide is then cooled by heat exchange with the hot water from the hot water supply unit in the aftercooler 18 to obtain medium temperature and high pressure carbon dioxide. The heated hot water enters the hot water tank 19 for storage. The medium temperature and high pressure carbon dioxide enters the second condenser 30 for cooling to obtain liquid low temperature and high pressure carbon dioxide, which is then stored in the liquid storage tank 8. At the same time, the hot water generated by the hot water supply unit enters the booster pump 23 for pressurization and then enters the first cooler 2, the second cooler 4, and the third cooler 6 for heat exchange and heating to obtain steam with a certain pressure.

[0053] The low-temperature, high-pressure carbon dioxide in storage tank 8 sequentially enters the second evaporator 25, the third heater 26, and the first turbine 9 for two heating cycles. After expansion, it drives a generator to produce electricity. The low-temperature, high-pressure carbon dioxide becomes ultra-low-temperature, sub-high-pressure carbon dioxide, which then sequentially enters the first refrigerator 20, the second preheater 27, the first heater 10, and the second turbine 11 for cooling. After two heating cycles, it expands and drives a generator to produce electricity. The ultra-low-temperature, sub-high-pressure carbon dioxide becomes ultra-low-temperature, medium-pressure carbon dioxide, which then sequentially enters the second refrigerator 21, the third preheater 28, the second heater 12, and the third turbine 13 for cooling. After two heating cycles, it expands and drives a generator to produce electricity. The generator produces ultra-low temperature medium-pressure carbon dioxide, which is then converted into ultra-low temperature normal-pressure carbon dioxide. This ultra-low temperature normal-pressure carbon dioxide sequentially enters the third refrigerator 22 and the post-preheater 29 for cooling and heating, and then becomes normal temperature normal-pressure carbon dioxide, which is stored in the gas storage chamber 7. At the same time, cooling water enters the first refrigerator 20, the second refrigerator 21 and the third refrigerator 22 to absorb cold energy and supply cold water or make ice to users. Hot water from the hot water supply unit enters the second evaporator 25, the second preheater 27, the third preheater 28 and the post-preheater 29 for heat exchange and cooling before being discharged. Hot water from the hot water tank 19 enters the third heater 26, the first heater 10 and the second heater 12 for heat exchange and cooling before being discharged.

[0054] The specific steps for the hot water supply unit to generate hot water are as follows:

[0055] Gaseous, low-temperature, medium-pressure carbon dioxide enters the fourth compressor 14 and is compressed to obtain medium-temperature, high-pressure carbon dioxide. The medium-temperature, high-pressure carbon dioxide enters the first condenser 15 and exchanges heat with cooling water, turning the cooling water into hot water for supply. The medium-temperature, high-pressure carbon dioxide then becomes liquid, room-temperature, high-pressure carbon dioxide. The liquid, room-temperature, high-pressure carbon dioxide enters the fourth turbine 16, expands, and generates mechanical energy to drive the fourth compressor 14. The room-temperature, high-pressure carbon dioxide then becomes liquid, low-temperature, medium-pressure carbon dioxide. The liquid, low-temperature, medium-pressure carbon dioxide enters the first evaporator 17 and exchanges heat with cooling water. The cooling water absorbs the cooling energy and supplies cold water to users or makes ice. The liquid, low-temperature, medium-pressure carbon dioxide then becomes gaseous, low-temperature, medium-pressure carbon dioxide and enters the fourth compressor 14 for circulation. The temperature remains constant before and after the change, and the cooling energy generated by the latent heat of vaporization provides cooling energy for the cooling water.

[0056] Specifically, the intermediate-temperature, atmospheric-pressure carbon dioxide sequentially enters the first compressor 1, the first cooler 2, the second compressor 3, the second cooler 4, the third compressor 5, and the third cooler 6 for three-stage compression and three-stage cooling to obtain sub-high-temperature, high-pressure carbon dioxide.

[0057] Medium-temperature, atmospheric-pressure carbon dioxide enters the first compressor 1 for compression to obtain high-temperature, medium-pressure carbon dioxide. The high-temperature, medium-pressure carbon dioxide enters the first cooler 2 for cooling to obtain sub-high-temperature, medium-pressure carbon dioxide. The sub-high-temperature, medium-pressure carbon dioxide enters the second compressor 3 for compression to obtain high-temperature, sub-high-pressure carbon dioxide. The high-temperature, sub-high-pressure carbon dioxide enters the second cooler 4 for cooling to obtain sub-high-temperature, sub-high-pressure carbon dioxide. The sub-high-temperature, sub-high-pressure carbon dioxide enters the third compressor 5 for compression to obtain high-temperature, high-pressure carbon dioxide. The high-temperature, high-pressure carbon dioxide enters the third cooler 6 for cooling to obtain sub-high-temperature, high-pressure carbon dioxide.

[0058] Specifically, the low-temperature, high-pressure carbon dioxide in the storage tank 8 sequentially enters the second evaporator 25 and the third heater 26, and undergoes two heating processes with the first turbine 9 before expanding and generating electricity by driving the generator.

[0059] Low-temperature, high-pressure carbon dioxide enters the second evaporator 25 for evaporation to obtain gaseous medium-temperature, high-pressure carbon dioxide. The medium-temperature, high-pressure carbon dioxide enters the third heater 26 for heating to obtain sub-high-temperature, high-pressure carbon dioxide. The sub-high-temperature, high-pressure carbon dioxide enters the first turbine 9 for expansion and work to obtain ultra-low-temperature, sub-high-pressure carbon dioxide.

[0060] Specifically, ultra-low temperature, sub-high pressure carbon dioxide sequentially enters the first refrigerator 20, the second preheater 27, the first heater 10, and the second turbine 11 for cooling. After two heating cycles, it expands and performs work to drive the generator to generate electricity.

[0061] The ultra-low temperature and sub-high pressure carbon dioxide sequentially enters the first refrigerator 20 for heat exchange and temperature rise to obtain low temperature and sub-high pressure carbon dioxide. The low temperature and sub-high pressure carbon dioxide enters the second preheater 27 for heat exchange and temperature rise to obtain medium temperature and sub-high pressure carbon dioxide. The medium temperature and sub-high pressure carbon dioxide enters the first heater 10 for heat exchange and temperature rise to obtain sub-high temperature and sub-high pressure carbon dioxide. The sub-high temperature and sub-high pressure carbon dioxide enters the second turbine 11 for expansion and work to obtain ultra-low temperature and medium pressure carbon dioxide.

[0062] Specifically, the ultra-low temperature medium-pressure carbon dioxide sequentially enters the second refrigerator 21, the third preheater 28, the second heater 12, and the third turbine 13 for cooling. After being heated twice, it expands and does work to drive the generator to generate electricity.

[0063] The ultra-low temperature medium pressure carbon dioxide enters the second refrigerator 21 for heat exchange and temperature rise to obtain low temperature medium pressure carbon dioxide. The low temperature medium pressure carbon dioxide enters the third preheater 28 for heat exchange and temperature rise to obtain medium temperature medium pressure carbon dioxide. The medium temperature medium pressure carbon dioxide enters the second heater 12 for heat exchange and temperature rise to obtain sub-high temperature medium pressure carbon dioxide. The sub-high temperature medium pressure carbon dioxide enters the third turbine 13 for expansion and work to obtain ultra-low temperature atmospheric pressure carbon dioxide.

[0064] Specifically, the ultra-low temperature and atmospheric pressure carbon dioxide sequentially enters the third refrigerator 22 and the post-preheater 29 for cooling and heating, and then becomes ambient temperature and atmospheric pressure carbon dioxide before entering the gas storage chamber 7 for storage.

[0065] Ultra-low temperature atmospheric pressure carbon dioxide enters the third refrigerator 22 for heat exchange and temperature rise to obtain low temperature atmospheric pressure carbon dioxide. The low temperature atmospheric pressure carbon dioxide enters the preheater 29 for heat exchange and temperature rise to obtain normal temperature atmospheric pressure carbon dioxide.

[0066] Among them, gaseous low-temperature medium-pressure carbon dioxide has a temperature of -5℃ to 5℃ and a pressure of 3MPa to 4MPa; medium-temperature high-pressure carbon dioxide has a temperature of 45℃ to 55℃ and a pressure of 6MPa to 7MPa; liquid room-temperature high-pressure carbon dioxide has a temperature of 15℃ to 25℃ and a pressure of 6MPa to 7MPa; liquid low-temperature medium-pressure carbon dioxide has a temperature of -5℃ to 5℃ and a pressure of 3MPa to 4MPa; medium-temperature normal-pressure carbon dioxide has a temperature of 35℃ to 45℃ and a pressure of 0.101MPa; high-temperature medium-pressure carbon dioxide has a temperature of 250℃ to 260℃ and a pressure of 0.8MPa to 0.9MPa; and sub-high-temperature medium-pressure carbon dioxide has a temperature of 1... The carbon dioxide produced in the high-temperature, low-pressure stage has a temperature of 250℃~260℃ and a pressure of 2.4MPa~2.5MPa, while the temperature of the high-temperature, low-pressure stage is 35℃~145℃ and the pressure is 0.8MPa~0.9MPa. The carbon dioxide entering the third compressor has a temperature of 135℃~145℃ and a pressure of 2.4MPa~2.5MPa, while the high-temperature, high-pressure stage has a temperature of 250℃~260℃ and a pressure of 6.9MPa~7.0MPa. The low-temperature, high-pressure stage has a temperature of 80℃~145℃ and a pressure of 6.9MPa~7.0MPa. The liquid low-temperature, high-pressure stage has a temperature of 20℃~25℃ and a pressure of 6.9MPa~7.0MPa. The temperature of ultra-low temperature sub-high pressure carbon dioxide is -10℃ to 0℃ and the pressure is 1.7MPa to 1.8MPa; the temperature of low temperature sub-high pressure carbon dioxide is 4℃ to 12℃ and the pressure is 1.7MPa to 1.8MPa; the temperature of medium temperature sub-high pressure carbon dioxide is 35℃ to 45℃ and the pressure is 1.7MPa to 1.8MPa; the temperature of sub-high temperature sub-high pressure carbon dioxide entering the second turbine 11 is 70℃ to 80℃ and the pressure is 0.4MPa to 0.5MPa; the temperature of ultra-low temperature medium pressure carbon dioxide is -10℃ to 0℃ and the pressure is 0.4MPa to 0.5MPa; the temperature of low temperature medium pressure carbon dioxide is 4℃ to 12℃ and the pressure is 0.0MPa. The pressure is 0.4MPa~0.5MPa. The temperature of medium-temperature and medium-pressure carbon dioxide is 35℃~45℃ and the pressure is 0.4MPa~0.5MPa. The temperature of sub-high temperature and medium-pressure carbon dioxide is 65℃~75℃ and the pressure is 0.4MPa~0.5MPa. The temperature of ultra-low temperature and normal pressure carbon dioxide is -10℃~0℃ and the pressure is 0.101MPa. The temperature of low temperature and normal pressure carbon dioxide is 4~12℃ and the pressure is 0.101MPa. The hot water produced by the first condenser 15 has a temperature of 40℃~45℃. The hot water in the hot water tank 19 has a temperature of 90℃~95℃. The steam with a certain pressure has a temperature greater than 200℃ and a pressure greater than 0.6MPa.

[0067] Working principle:

[0068] In the initial state, the first control valve 31, the second control valve 32, the third control valve 33, and the fourth control valve 34 are closed, and the device is in a stopped state. When the user needs to start the system, the first control valve 31, the second control valve 32, the third control valve 33, and the fourth control valve 34 are opened.

[0069] Gaseous, low-temperature, medium-pressure carbon dioxide enters the fourth compressor 14 and is compressed to obtain medium-temperature, high-pressure carbon dioxide. The medium-temperature, high-pressure carbon dioxide enters the first condenser 15 and exchanges heat with cooling water, turning the cooling water into hot water for supply. The medium-temperature, high-pressure carbon dioxide becomes liquid, room-temperature, high-pressure carbon dioxide. The liquid, room-temperature, high-pressure carbon dioxide enters the fourth turbine 16, expands, and generates mechanical energy to drive the fourth compressor 14. The room-temperature, high-pressure carbon dioxide becomes liquid, low-temperature, medium-pressure carbon dioxide. The liquid, low-temperature, medium-pressure carbon dioxide enters the first evaporator 17 and exchanges heat with cooling water. The cooling water absorbs cold energy and supplies cold water to users or makes ice. The liquid, low-temperature, medium-pressure carbon dioxide becomes gaseous, low-temperature, medium-pressure carbon dioxide and enters the fourth compressor 14 for circulation.

[0070] The hot water generated in the first condenser 15 is sent to the first preheater 24 to preheat the ambient temperature and atmospheric pressure carbon dioxide to obtain medium temperature and ambient pressure carbon dioxide. The medium temperature and ambient pressure carbon dioxide enters the first compressor 1 for compression to obtain high temperature and medium pressure carbon dioxide. The high temperature and medium pressure carbon dioxide enters the first cooler 2 for cooling to obtain sub-high temperature and medium pressure carbon dioxide. The sub-high temperature and medium pressure carbon dioxide enters the second compressor 3 for compression to obtain high temperature and sub-high pressure carbon dioxide. The high temperature and sub-high pressure carbon dioxide enters the second cooler 4 for cooling to obtain sub-high temperature and sub-high pressure carbon dioxide. The sub-high temperature and sub-high pressure carbon dioxide enters the third compressor 5 for compression to obtain high temperature and high pressure carbon dioxide. The high temperature and high pressure carbon dioxide enters the third cooler 6. Cooling produces sub-high temperature, high pressure carbon dioxide. The sub-high temperature, high pressure carbon dioxide aftercooler 18 exchanges heat with hot water from the first condenser 15 to obtain medium temperature, high pressure carbon dioxide. The heated hot water enters the hot water tank 19 for storage. The medium temperature, high pressure carbon dioxide enters the second condenser 30 to exchange heat with cooling water, and the medium temperature, high pressure carbon dioxide becomes liquid low temperature, high pressure carbon dioxide, which enters the storage tank 8 for storage. The heated cooling water enters the water storage tank. At the same time, the hot water from the first condenser 15 enters the booster pump 23 for pressurization and then enters the first cooler 2, the second cooler 4, and the third cooler 6 respectively for heat exchange and heating to obtain steam with a certain pressure, which is then supplied to the user with steam with a certain pressure.

[0071] Low-temperature, high-pressure carbon dioxide in storage tank 8 enters the second evaporator 25 for evaporation to obtain gaseous medium-temperature, high-pressure carbon dioxide. This medium-temperature, high-pressure carbon dioxide then enters the third heater 26 for heating to obtain sub-high-temperature, high-pressure carbon dioxide. This sub-high-temperature, high-pressure carbon dioxide then enters the first turbine 9, where it expands and drives a generator to produce electricity. The sub-high-temperature, high-pressure carbon dioxide then becomes ultra-low-temperature, sub-high-pressure carbon dioxide. This ultra-low-temperature, sub-high-pressure carbon dioxide then enters the first refrigerator 20 for heat exchange and temperature increase to obtain low-temperature, sub-high-pressure carbon dioxide. This low-temperature, sub-high-pressure carbon dioxide then enters the second preheater 27 for heat exchange and temperature increase to obtain medium-temperature, sub-high-pressure carbon dioxide. This medium-temperature, sub-high-pressure carbon dioxide then enters the first heater 10 for heat exchange and temperature increase to obtain sub-high-temperature, sub-high-pressure carbon dioxide. This sub-high-temperature, sub-high-pressure carbon dioxide then enters the second turbine 11 for expansion and work, driving a generator to produce electricity. This sub-high-temperature, sub-high-pressure carbon dioxide then becomes ultra-low-temperature, sub-pressure carbon dioxide. This ultra-low-temperature, sub-pressure carbon dioxide then enters the second refrigerator 21 for heat exchange and temperature increase to obtain low-temperature, sub-pressure carbon dioxide. This low-temperature, sub-pressure carbon dioxide then enters... The third preheater 28 heats up to obtain medium-temperature, medium-pressure carbon dioxide. The medium-temperature, medium-pressure carbon dioxide enters the second heater 12 for heat exchange and heat up to obtain sub-high-temperature, medium-pressure carbon dioxide. The sub-high-temperature, medium-pressure carbon dioxide enters the third turbine 13 for expansion and work, driving the generator to generate electricity. The sub-high-temperature, medium-pressure carbon dioxide becomes ultra-low-temperature, normal-pressure carbon dioxide. The ultra-low-temperature, normal-pressure carbon dioxide enters the third refrigerator 22 for heat exchange and heat up to obtain low-temperature, normal-pressure carbon dioxide. The low-temperature, normal-pressure carbon dioxide enters the post-preheater 29 for heat exchange and heat up to obtain normal-temperature, normal-pressure carbon dioxide, which is then stored in the gas storage chamber 7. At the same time, cooling water enters the first refrigerator 20, the second refrigerator 21, and the third refrigerator 22 to absorb cold energy and supply cold water or make ice to users. The hot water from the hot water supply unit enters the second evaporator 25, the second preheater 27, the third preheater 28, and the post-preheater 29 for heat exchange and cooling before being discharged. The hot water from the hot water tank 19 enters the third heater 26, the first heater 10, and the second heater 12 for heat exchange and cooling before being discharged.

[0072] It is understood that this invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this invention. Furthermore, under the teachings of this invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this invention. Therefore, this invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this invention are within the protection scope of this invention.

Claims

1. A multi-energy production carbon dioxide power cycle system, comprising a gas storage bin (7), a first compressor (1), a first cooler (2), a liquid storage tank (8), a first turbine (9) and a post-preheater (29) connected in sequence, characterized in that, Also comprising: a hot water supply unit connected with the first cooler (2) and the post-preheater (29) respectively, for sending hot water into the first cooler (2) to absorb heat to obtain steam to supply to users, and sending hot water into the post-preheater (29) to provide heat for the expanded carbon dioxide; a waste heat recovery unit comprising a post-cooler (18) and a hot water tank (19), the first inlet of the post-cooler (18) being connected with the first cooler (2), the first outlet of the post-cooler (18) being connected with the liquid storage tank (8), the second inlet of the post-cooler (18) being connected with the hot water supply unit, the second outlet of the post-cooler (18) being connected with the inlet of the hot water tank (19), for storing the hot water into the hot water tank (19) after absorbing the waste heat of the compressed carbon dioxide, and using the stored hot water to increase the temperature of the carbon dioxide at the inlet of the first turbine (9); a cold energy recovery unit comprising a first refrigeration unit (20), the first refrigeration unit (20) being arranged between the first turbine (9) and the post-preheater (29), the first refrigeration unit (20) being used to introduce cooling water to absorb the cold energy in the expanded carbon dioxide after work, to supply cold water or ice to users; the hot water supply unit comprises a fourth compressor (14), a first condenser (15), a fourth turbine (16) and a first evaporator (17) connected in sequence, the fourth compressor (14) is used to compress carbon dioxide, the first inlet of the first condenser (15) is used to introduce cooling water to absorb the heat in the compressed carbon dioxide, the first outlet of the first condenser (15) is connected with the first cooler (2), the fourth turbine (16) is used to make the compressed carbon dioxide expand to work to generate mechanical energy to drive the fourth compressor (14), and the first inlet of the first evaporator (17) is used to introduce cooling water to absorb the cold energy of the expanded carbon dioxide, to supply cold water or ice to users.

2. A multi-capable co-produced carbon dioxide power cycle system according to claim 1, wherein, The first outlet of the first condenser (15) is provided with a booster pump (23), the inlet of the booster pump (23) is connected with the first outlet of the first condenser (15), and the outlet of the booster pump (23) is connected with the first cooler (2).

3. A multi-capable co-produced carbon dioxide power cycle system according to claim 2, wherein, A first preheater (24) is arranged between the gas storage bin (7) and the first compressor (1), and the first preheater (24) is used to preheat the carbon dioxide with the hot water provided by the first condenser (15).

4. A multi-capable co-produced carbon dioxide power cycle system according to claim 2, wherein, The first cooler (2) and the liquid storage tank (8) are sequentially connected with the second compressor (3), the second cooler (4), the third compressor (5) and the third cooler (6), the first refrigeration device (20) and the post-preheater (29) are sequentially connected with the second preheater (27), the first heater (10), the second turbine (11), the second refrigeration device (21), the third preheater (28), the second heater (12), the third turbine (13) and the third refrigeration device (22), the first inlets of the second cooler (4) and the third cooler (6) are connected with the outlet of the booster pump (23) respectively, the first inlets of the second preheater (27) and the third preheater (28) are connected with the first outlet of the first condenser (15) respectively, the first inlets of the first heater (10) and the second heater (12) are connected with the outlet of the hot water tank (19) respectively.

5. A poly-generation carbon dioxide power cycle system according to claim 4, wherein, The outlet of the liquid storage tank (8) is provided with the second evaporator (25), the first inlet of the second evaporator (25) is connected with the outlet of the liquid storage tank (8), the first outlet of the second evaporator (25) is provided with the third heater (26), the second inlet of the second evaporator (25) is connected with the first outlet of the first condenser (15), the first inlet of the third heater (26) is connected with the first outlet of the second evaporator (25), the first outlet of the third heater (26) is connected with the inlet of the first turbine (9), the second inlet of the third heater (26) is connected with the outlet of the hot water tank (19).

6. A poly-generation carbon dioxide power cycle system according to claim 5, wherein, The post-cooler (18) and the liquid storage tank (8) are provided with the second condenser (30), the first inlet of the second condenser (30) is connected with the first outlet of the post-cooler (18), the first outlet of the second condenser (30) is connected with the inlet of the liquid storage tank (8), and the second inlet of the second condenser (30) is used for introducing cooling water.

7. A polytropic co-production of carbon dioxide power cycle method characterized by, The system of claim 6 comprises the following steps: The hot water supply unit generates hot water, the hot water is transported to the outlet of the gas storage bin (7) to preheat the normal-temperature and normal-pressure carbon dioxide to obtain medium-temperature and normal-pressure carbon dioxide, the medium-temperature and normal-pressure carbon dioxide enters the first compressor (1) and the first cooler (2) in sequence to be compressed and cooled to obtain high-temperature and high-pressure carbon dioxide, the high-temperature and high-pressure carbon dioxide is cooled by the post-cooler (18) and the hot water from the hot water supply unit to obtain high-temperature and high-pressure carbon dioxide, the heated hot water enters the hot water tank (19) for storage, the hot water supply unit generates hot water which is pressurized by the booster pump (23) and then enters the first cooler (2) to be heated to obtain steam; The low-temperature high-pressure carbon dioxide in the liquid storage tank (8) enters the second evaporator (25), the third heater (26) and the first turbine (9) in sequence to expand and do work after being heated twice, to drive the generator to generate electricity, and the low-temperature high-pressure carbon dioxide becomes ultra-low-temperature normal-pressure carbon dioxide, which enters the third refrigerating device (22) and the post-preheater (29) to be cooled and heated, and then becomes normal-temperature normal-pressure carbon dioxide and is stored in the gas storage bin (7), at the same time, the cooling water enters the first refrigerating device (20) to absorb cold energy, to supply cold water or make ice to the user, and the hot water of the hot water supply unit enters the second evaporator (25) and the post-preheater (29) to be heat-exchanged and cooled, and then is discharged, and the hot water from the hot water tank (19) enters the third heater (26) to be heat-exchanged and cooled, and then is discharged.

8. A polytropic carbon dioxide power cycle method according to claim 7, wherein, The specific steps of the operation of the hot water supply unit to generate hot water are as follows: The gaseous low-temperature medium-pressure carbon dioxide enters the fourth compressor (14) to be compressed to obtain medium-temperature high-pressure carbon dioxide, the medium-temperature high-pressure carbon dioxide enters the first condenser (15) to be heat-exchanged with the cooling water, the cooling water becomes hot water to be supplied, the medium-temperature high-pressure carbon dioxide becomes liquid normal-temperature high-pressure carbon dioxide, the liquid normal-temperature high-pressure carbon dioxide enters the fourth turbine (16) to expand and do work to generate mechanical energy to drive the fourth compressor (14), the normal-temperature high-pressure carbon dioxide becomes liquid low-temperature medium-pressure carbon dioxide, the liquid low-temperature medium-pressure carbon dioxide enters the first evaporator (17) to be heat-exchanged with the cooling water, the cooling water absorbs cold energy to supply cold water or make ice to the user, and the liquid low-temperature medium-pressure carbon dioxide becomes gaseous low-temperature medium-pressure carbon dioxide to enter the fourth compressor (14) to circulate.

9. A polytropic carbon dioxide power cycle method according to claim 8, wherein, The temperature of the medium-temperature normal-pressure carbon dioxide is 35-45℃, the pressure is 0.101MPa, the temperature of the sub-high-temperature high-pressure carbon dioxide is 80-145℃, the pressure is 6.9-7.0MPa, the temperature of the medium-temperature high-pressure carbon dioxide is 45-55℃, the pressure is 6-7MPa, the temperature of the liquid low-temperature high-pressure carbon dioxide is -5-5℃, the pressure is 3-4MPa, the temperature of the ultra-low-temperature normal-pressure carbon dioxide is -10-0℃, the pressure is 0.101MPa, the temperature of the gaseous low-temperature medium-pressure carbon dioxide is -5-5℃, the pressure is 3-4MPa, the temperature of the medium-temperature high-pressure carbon dioxide is 45-55℃, the pressure is 6-7MPa, the temperature of the liquid normal-temperature high-pressure carbon dioxide is 15-25℃, the pressure is 6-7MPa, and the temperature of the liquid low-temperature medium-pressure carbon dioxide is -5-5℃, the pressure is 3-4MPa.

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