A power generation system combining a nuclear power unit and an absorption heat pump and a working method thereof

Abstract

The present invention discloses a power generation system combining a nuclear power unit with an absorption heat pump and a working method thereof, comprising a nuclear reactor, a steam generator, an absorption heat pump unit and a power generation unit; the gas outlet of the nuclear reactor is connected to the hot end inlet of the steam generator, and the hot end outlet of the steam generator is connected to the gas inlet of the nuclear reactor; the cold end of the steam generator is connected to the input heat source end of the absorption heat pump unit; the power generation unit comprises a steam turbine and a generator connected in sequence, and the output heat source end outlet of the absorption heat pump unit is connected to the turbine inlet. The nuclear power unit is combined with the absorption heat pump to realize the transmission of heat energy from low temperature to high temperature, and the temperature of the medium-temperature steam heat energy generated by the nuclear reactor is increased. Compared with the traditional pressurized water reactor nuclear power plant, a higher power cycle efficiency can be obtained, and high-quality conversion of nuclear energy can be achieved. The problem of low power cycle efficiency caused by low steam parameters in the nuclear power system is solved, and efficient utilization of nuclear energy is achieved.

Description

Technical Field

[0001] The invention belongs to the field of nuclear power generation, and relates to a power generation system combining a nuclear power unit with an absorption heat pump and a working method thereof. Background Art

[0002] Pressurized water reactors are the main type of reactor used in operating nuclear power plants in the world, and their total installed capacity accounts for more than (60)% of the total of all types of reactors in all nuclear power plants. Among various types of power reactors, pressurized water reactors have been widely used due to their compact structure, small size, high power density, high average burnup, low escape of radioactive fission products, good power self-stabilization and self-regulation characteristics, and relatively safe and reliable. The conventional island of a pressurized water reactor nuclear power plant generates steam of more than (300) degrees through a nuclear reactor and generates electricity through a thermal cycle. Since the main steam parameters of a pressurized water reactor nuclear power plant are relatively low and the steam temperature is not high, the improvement of the power generation efficiency of the nuclear power plant is seriously restricted. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a power generation system combining a nuclear power unit and an absorption heat pump and a working method thereof, so as to increase the steam temperature, obtain a higher power cycle efficiency, and realize high-quality conversion of nuclear energy.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A power generation system combining a nuclear power unit and an absorption heat pump, comprising a nuclear reactor, a steam generator, an absorption heat pump unit and a power generation unit;

[0006] The gas outlet of the nuclear reactor is connected to the hot end inlet of the steam generator, and the hot end outlet of the steam generator is connected to the gas inlet of the nuclear reactor; the cold end of the steam generator is connected to the input heat source end of the absorption heat pump unit;

[0007] The power generation unit comprises a steam turbine and a generator connected in sequence, and the output heat source end outlet of the absorption heat pump unit is connected to the steam turbine inlet.

[0008] Preferably, the absorption heat pump includes a generator, a condenser, an evaporator and an absorber; the hot end of the generator serves as the input heat source end of the absorption heat pump unit, the cold end outlet of the steam generator is connected to the hot end inlet of the generator, the hot end outlet of the generator is connected to the cold end inlet of the steam generator, and the refrigerant outlet of the generator is connected to the hot end of the condenser, the cold end of the evaporator and the solution inlet of the absorber in sequence; the cold end of the condenser serves as the output heat source end of the absorption heat pump unit, and the cold end outlet of the condenser is connected to the turbine inlet; the solution outlet of the generator is connected to the solution inlet of the absorber, and the solution outlet of the absorber is connected to the solution inlet of the generator.

[0009] Furthermore, a throttle valve is provided between the hot end of the condenser and the cold end of the evaporator.

[0010] Furthermore, a circulation pump is provided between the solution outlet of the absorber and the solution inlet of the generator.

[0011] Furthermore, the exhaust outlet of the steam turbine is connected to the hot end inlet of the evaporator, the hot end outlet of the evaporator is connected to the cold end inlet of the absorber, and the cold end outlet of the absorber is connected to the cold end inlet of the condenser.

[0012] Furthermore, the steam extraction outlet of the steam turbine is connected to the hot end inlet of the feedwater heater, the hot end outlet of the feedwater heater is connected to the hot end inlet of the evaporator, the hot end outlet of the evaporator is connected to the cold end inlet of the feedwater heater, and the cold end outlet of the feedwater heater is connected to the cold end inlet of the absorber.

[0013] Furthermore, the steam turbine is provided with three-stage steam extraction outlets, each of which is connected to a feedwater heater, and the cold ends and hot ends of the three feedwater heaters are connected in series in sequence.

[0014] Furthermore, a condensate pump is provided between the hot end outlet of the evaporator and the cold end inlet of the feedwater heater.

[0015] A method for operating a power generation system based on any one of the above-mentioned nuclear power units combined with an absorption heat pump, comprising the following process:

[0016] The energy generated by the nuclear reactor is transferred to the cold end of the steam generator, which generates medium-temperature water vapor. The medium-temperature water vapor is used to drive the absorption heat pump unit. The absorption heat pump unit outputs high-temperature and high-pressure steam into the steam turbine to perform work, driving the generator to output electrical energy.

[0017] Preferably, the high-temperature and high-pressure steam generated by the condenser in the absorption heat pump unit enters the steam turbine to perform work, driving the generator to output electrical energy; after power generation, the water vapor is transported to the evaporator through the exhaust outlet for condensation, pressurized by the condensate pump, and preheated by the feed water heater before entering the absorber and the cold end of the condenser in turn, generating high-temperature and high-pressure steam, completing the circulation process of the power generation unit.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention combines a nuclear power unit with an absorption heat pump to achieve heat transfer from low temperature to high temperature, and to increase the temperature of the medium-temperature steam heat energy generated by the nuclear reactor. Compared with traditional pressurized water reactor nuclear power plants, it can achieve higher power cycle efficiency and achieve high-quality conversion of nuclear energy. It solves the problem of low power cycle efficiency caused by low steam parameters in nuclear power systems and achieves efficient utilization of nuclear energy.

[0020] Furthermore, since the evaporator of the absorption heat pump is used to condense the exhaust steam of the steam turbine, a cooling tower and cooling water are not required, thereby achieving a water-saving effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the system structure of the present invention.

[0022] Among them: 1-nuclear reactor; 2-steam generator; 3-generator; 4-condenser; 5-evaporator; 6-absorber; 7-throttle valve; 8-circulating pump; 9-steam turbine; 10-generator; 11-condensate pump; 12-feedwater heater. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0024] like Figure 1 As shown, the power generation system of the nuclear power unit combined with the absorption heat pump according to the present invention includes a nuclear reactor unit, an absorption heat pump unit, and a power generation unit.

[0025] The nuclear reactor unit releases heat through the nuclear reactor to generate medium-temperature water vapor of more than 300°C, which is used to drive the generator of the absorption heat pump unit.

[0026] The absorption heat pump unit uses the medium-temperature water vapor provided by the nuclear reactor unit as the driving heat source, and utilizes the absorbent to release and absorb heat during the absorption and desorption process of the refrigerant, thereby transferring heat energy from low temperature to high temperature, converting the medium-temperature heat energy into high-temperature heat energy above 500°C, and transferring it to the power generation unit.

[0027] The power generation unit is used to absorb the heat energy above 500°C of the absorption heat pump unit, heat the working medium water, and convert it into high-temperature and high-pressure steam. The received heat energy is converted into electrical energy and output through the steam turbine and generator set.

[0028] The nuclear reactor unit comprises a nuclear reactor 1 and a steam generator 2 , wherein the gas outlet of the nuclear reactor 1 is connected to the hot end inlet of the steam generator 2 , and the hot end outlet of the steam generator 2 is connected to the gas inlet of the nuclear reactor 1 .

[0029] The absorption heat pump includes a generator 3, a condenser 4, an evaporator 5 and an absorber 6; the refrigerant outlet of the generator 3 is connected to the refrigerant inlet of the condenser 4, the refrigerant outlet of the condenser 4 is connected to the refrigerant inlet of the evaporator 5 through a throttle valve 7, the refrigerant outlet of the evaporator 5 is connected to the refrigerant inlet of the absorber 6, the dilute solution outlet of the absorber 6 is connected to the dilute solution inlet of the generator 3 through a circulating pump 8, and the concentrated solution outlet of the generator 3 is connected to the concentrated solution inlet of the absorber 6.

[0030] Specifically: the hot end of the generator 3 serves as the input heat source end of the absorption heat pump unit, the cold end outlet of the steam generator 2 is connected to the hot end inlet of the generator 3, the hot end outlet of the generator 3 is connected to the cold end inlet of the steam generator 2, and the refrigerant outlet of the generator 3 is connected to the hot end of the condenser 4, the cold end of the evaporator 5 and the solution inlet of the absorber 6 in sequence; the cold end of the condenser 4 serves as the output heat source end of the absorption heat pump unit, and the cold end outlet of the condenser 4 is connected to the inlet of the turbine 9; the solution outlet of the generator 3 is connected to the solution inlet of the absorber 6, and the solution outlet of the absorber 6 is connected to the solution inlet of the generator 3.

[0031] The power generation unit includes a steam turbine 9, a generator 10 and a condensate pump 11. The exhaust outlet of the steam turbine 9 is connected to the hot end inlet of the evaporator 5, the hot end outlet of the evaporator 5 is connected to the cold end inlet of the absorber 6, and the cold end outlet of the absorber 6 is connected to the cold end inlet of the condenser 4.

[0032] The steam extraction outlet of the steam turbine 9 is connected to the hot end inlet of the feed water heater 12, the hot end outlet of the feed water heater 12 is connected to the hot end inlet of the evaporator 5, the hot end outlet of the evaporator 5 is connected to the cold end inlet of the feed water heater 12 through the condensate pump 11, and the cold end outlet of the feed water heater 12 is connected to the cold end inlet of the absorber 6.

[0033] The steam turbine 9 is provided with three-stage steam extraction outlets, each of which is connected to a feedwater heater 12, and the cold ends and hot ends of the three feedwater heaters 12 are respectively connected in series.

[0034] The energy generated by the nuclear reactor 1 is transferred to the steam generator 2 to generate medium-temperature water vapor, which is used to drive the generator 3 of the absorption heat pump unit.

[0035] The working medium in the absorption heat pump unit includes a refrigerant and an absorbent solution that absorbs and desorbs the refrigerant, and the two constitute a working medium pair; the heat transfer working medium is used to heat a solution with a certain concentration delivered from the absorber 6 by the circulating pump 8 in the generator 3, and most of the low-boiling point refrigerant in the solution evaporates; the refrigerant vapor enters the condenser 4, and heats the working medium water of the power generation unit into high-temperature and high-pressure steam. At the same time, the refrigerant is condensed into a refrigerant liquid by the cooling medium, and then the pressure is reduced to the evaporation pressure through the throttle valve 7; the refrigerant enters the evaporator 5 through the throttling In the generator 3, the concentrated solution remaining after the generation process is reduced to the evaporation pressure through the throttle valve 8 and enters the absorber 6, where it is mixed with the low-pressure refrigerant vapor coming out of the evaporator 5, absorbs the low-pressure refrigerant vapor and restores to the original concentration; the absorption process is an exothermic process, which heats the feed water from the feed water heater; the solution whose concentration has been restored in the absorber 6 is then pressurized by the circulating pump 8 and sent to the generator 3 for continued circulation.

[0036] The power generation unit includes a steam turbine 9, a generator 10, and a condensate pump 11, wherein the high-temperature and high-pressure steam generated by the condenser 4 in the absorption heat pump unit enters the steam turbine 9 to perform work, driving the generator 10 to output electrical energy. After power generation, the water vapor is condensed in the evaporator 5 in the absorption heat pump unit, pressurized by the condensate pump 11, and preheated by the feedwater heater 12 before entering the absorber 6 and the condenser 4 in turn, generating high-temperature and high-pressure steam, completing the cycle process of the power generation unit.

[0037] 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 it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A power generation system combining a nuclear power unit and an absorption heat pump, characterized in that: It comprises a nuclear reactor (1), a steam generator (2), an absorption heat pump unit and a power generation unit; The gas outlet of the nuclear reactor (1) is connected to the hot end inlet of the steam generator (2), and the hot end outlet of the steam generator (2) is connected to the gas inlet of the nuclear reactor (1); the cold end of the steam generator (2) is connected to the input heat source end of the absorption heat pump unit; The power generation unit comprises a steam turbine (9) and a generator (10) connected in sequence, and the output heat source outlet of the absorption heat pump unit is connected to the inlet of the steam turbine (9); The absorption heat pump comprises a generator (3), a condenser (4), an evaporator (5) and an absorber (6); the hot end of the generator (3) serves as an input heat source end of the absorption heat pump unit, the cold end outlet of the steam generator (2) is connected to the hot end inlet of the generator (3), the hot end outlet of the generator (3) is connected to the cold end inlet of the steam generator (2), and the refrigerant outlet of the generator (3) is connected to the hot end of the condenser (4), the cold end of the evaporator (5) and the solution inlet of the absorber (6) in sequence; the cold end of the condenser (4) serves as an output heat source end of the absorption heat pump unit, and the cold end outlet of the condenser (4) is connected to the inlet of the turbine (9); the solution outlet of the generator (3) is connected to the solution inlet of the absorber (6), and the solution outlet of the absorber (6) is connected to the solution inlet of the generator (3); A throttle valve (7) is provided between the hot end of the condenser (4) and the cold end of the evaporator (5); A circulation pump (8) is provided between the solution outlet of the absorber (6) and the solution inlet of the generator (3); The exhaust steam outlet of the steam turbine (9) is connected to the hot end inlet of the evaporator (5), the hot end outlet of the evaporator (5) is connected to the cold end inlet of the absorber (6), and the cold end outlet of the absorber (6) is connected to the cold end inlet of the condenser (4); The steam extraction outlet of the steam turbine (9) is connected to the hot end inlet of the feed water heater (12), the hot end outlet of the feed water heater (12) is connected to the hot end inlet of the evaporator (5), the hot end outlet of the evaporator (5) is connected to the cold end inlet of the feed water heater (12), and the cold end outlet of the feed water heater (12) is connected to the cold end inlet of the absorber (6); The steam turbine (9) is provided with three stages of steam extraction outlets, each stage of the steam extraction outlet is connected to a feed water heater (12), and the cold ends and hot ends of the three feed water heaters (12) are respectively connected in series.

2. The power generation system combining a nuclear power unit and an absorption heat pump according to claim 1, characterized in that: A condensate pump (11) is provided between the hot end outlet of the evaporator (5) and the cold end inlet of the feed water heater (12).

3. A method for operating a power generation system based on a nuclear power unit combined with an absorption heat pump according to any one of claims 1 to 2, characterized in that: The process includes: The energy generated by the nuclear reactor (1) is transmitted to the cold end of the steam generator (2), and the cold end of the steam generator (2) generates medium-temperature water vapor. The medium-temperature water vapor is used to drive the absorption heat pump unit. The absorption heat pump unit outputs high-temperature and high-pressure steam to enter the steam turbine (9) to perform work, thereby driving the generator (10) to output electrical energy.

4. The working method of the power generation system combining a nuclear power unit and an absorption heat pump according to claim 3, characterized in that: The high-temperature and high-pressure steam generated by the condenser (4) in the absorption heat pump unit enters the steam turbine (9) to perform work, driving the generator (10) to output electrical energy; after power generation, the water vapor is transported to the evaporator (5) through the exhaust outlet for condensation, and is pressurized by the condensate pump (11). After being preheated by the feed water heater (12), it enters the absorber (6) and the cold end of the condenser (4) in turn to generate high-temperature and high-pressure steam, completing the cycle process of the power generation unit.

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