Thermal management method based on nuclear power plant equipment and nuclear power plant heat source management system

Abstract

The invention provides a thermal management method based on nuclear power plant equipment and a nuclear power plant heat source management system.The thermal management method comprises the steps that a cascade waste heat utilization system is controlled to be switched to a heat supply running state, and the temperature of auxiliary equipment is absorbed through a low-temperature waste heat management system so that low-temperature heat sources can be provided for a double-effect absorption heat pump system and a single-effect absorption heat pump system; the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger are used for absorbing auxiliary waste heat in a stepped mode to provide heat for hot water supply, and heat supply circulation is completed. And the cascade waste heat utilization system is controlled to be switched to a cooling operation state, the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger are used for absorbing auxiliary waste heat in a stepped mode, circulating heat dissipation is conducted through the low-temperature waste heat management system, and cooling circulation is completed. Through the mode of combining the double-effect absorption system, the single-effect absorption system and heat exchange, the steam internal energy of the nuclear power plant is utilized in a gradient mode, the energy utilization efficiency is improved, and resource waste is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of waste heat energy treatment in nuclear power plants, and in particular to a thermal management method based on nuclear power plant equipment and a heat source management system for a nuclear power plant. Background Art

[0002] Nuclear power is a zero-CO2 emission power generation method. In a nuclear reactor, the energy generated by nuclear fission is converted into internal energy and absorbed by cooling water. The cooling water that has absorbed a large amount of energy is converted into high-temperature and high-pressure steam through a steam generator and passed into a steam turbine generator. In the steam turbine, the steam drives the turbine blades to generate electricity, converting internal energy into electrical energy. The steam flowing out after power generation generally has a high temperature of more than 150°C, which still has a high utilization value. The current way to utilize high-temperature steam is generally to exchange heat with a hot water production and distribution system to provide heating for reactor buildings, fuel plants, etc. under cold climate conditions. In hot climate conditions, the hot water production and distribution system needs to provide chilled water at about 7°C to relay rooms, DC distribution rooms, etc., to promptly remove the heat generated by the operation of key equipment and ensure the safe and normal operation of the nuclear power plant circuit.

[0003] The existing thermal management system of nuclear power plant equipment has the problems of complex structure and low energy utilization rate. Specifically, in the heating process, auxiliary steam exceeding 150℃ is directly heat exchanged to produce hot water at 60-70℃. Due to the large temperature difference of heat exchange, a large amount of Loss, and using steam through traditional direct heat exchange, due to the small temperature reduction of steam, the heat of the steam after heat exchange cannot be used, further causing energy waste. Summary of the invention

[0004] In view of this, the purpose of this application is to provide at least a thermal management method based on nuclear power plant equipment and a nuclear power plant heat source management system, which can gradiently utilize the internal energy of nuclear power plant steam through a double-effect absorption system, a single-effect absorption system and a heat exchange combination, thereby improving energy utilization efficiency and avoiding waste of resources.

[0005] This application mainly includes the following aspects:

[0006] In the first aspect, an embodiment of the present application provides a thermal management method based on nuclear power plant equipment, and the method is applied to a nuclear power plant heat source management system, wherein the nuclear power plant heat source management system includes a combined heat and cold supply system and a low-temperature waste heat management system, wherein the combined heat and cold supply system includes a double-effect absorption heat pump system, a single-effect absorption heat pump system, a first heat exchanger and a cascade waste heat utilization system, and auxiliary steam is connected to a steam output end through a steam pipeline via the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger, wherein the method includes: determining that the current ambient temperature is less than a first temperature threshold, then executing a heating cycle: controlling the cascade waste heat utilization system to switch to a heating operation state, so that the hot water input from the heating return water end is divided into three paths and flows into the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger respectively; utilizing the auxiliary steam to release heat in a stepwise manner through the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger, and The three hot water supply routes are summarized and output to the heat-using end; the waste heat generated by the production auxiliary equipment in the nuclear power plant is absorbed by the low-temperature waste heat management system, and a low-temperature heat source is provided for the double-effect absorption heat pump system and the single-effect absorption heat pump system respectively; when it is determined that the current ambient temperature is greater than or equal to the first temperature threshold, a cooling cycle is executed: the cascade waste heat utilization system is controlled to switch to the cooling operation state, so that the cooling water input from the cooling return water end flows into the double-effect absorption heat pump system and the single-effect absorption heat pump system in two routes respectively; the auxiliary steam is gradiently utilized to provide a high-temperature heat source for the double-effect absorption heat pump system and the single-effect absorption heat pump system, so that the double-effect absorption heat pump system and the single-effect absorption heat pump system absorb heat from the cooling water; the two cooling water outputs of the double-effect absorption heat pump system and the single-effect absorption heat pump system are summarized and output to the cold end; the low-temperature waste heat management system is used to dissipate the waste heat generated by the auxiliary equipment, the double-effect absorption heat pump system and the single-effect absorption heat pump system.

[0007] In a possible implementation manner, the combined cooling and heating system further includes a first circulation pump, and the cascade waste heat utilization system includes a first stop valve, a second stop valve, a third stop valve, a fourth stop valve and a first three-way valve, one end of the first stop valve is connected to a heat supply return water end, and the other end of the first stop valve is respectively connected to a first end of the first three-way valve through a circulating water pipeline via a double-effect absorption heat pump system, and is connected to a first end of the first three-way valve through a circulating water pipeline via a single-effect absorption heat pump system, and is connected to a first end of the first three-way valve through a circulating water pipeline via a second stop valve and a first heat exchanger, the second end of the first three-way valve is connected to a heat use end, one end of the third stop valve is connected to a cold supply return water, the other end of the third stop valve is connected to one end of the fourth stop valve through a circulating water pipeline via a single-effect absorption heat pump system, and the other end of the fourth stop valve is connected to a cold use end, wherein, during the heat supply cycle, the method further includes: respectively controlling the first stop valve and the second stop valve to open and the third stop valve and the fourth stop valve to close; controlling the first end of the first three-way valve and the second end of the first three-way valve; controlling the hot water supply to be input into the first circulation pump through the first stop valve, so that under the action of the first circulation pump, the hot water supply is divided into three paths and respectively input into the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger; performing the first-stage heat absorption treatment on the auxiliary steam flowing in from the steam input end through the hot water supply flowing into the double-effect absorption heat pump system, and the auxiliary steam after the first-stage heat absorption treatment is input into the single-effect absorption heat pump system; performing the second-stage heat absorption treatment on the auxiliary steam flowing in from the steam input end through the hot water supply flowing into the single-effect absorption heat pump system, and inputting the auxiliary steam after the second-stage heat absorption treatment into the first heat exchanger; performing the third-stage heat absorption treatment on the auxiliary steam input from the single-effect absorption heat pump system by using the first heat exchanger, and outputting the auxiliary steam after the second-stage heat absorption treatment to the steam output end; summarizing the heat-absorbed hot water outputted from the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger and connecting to the hot end through the first end of the first three-way valve and the second end of the first three-way valve.

[0008] In a possible embodiment, the cascade waste heat utilization system also includes a second three-way valve, a third three-way valve, a fourth three-way valve and a fifth three-way valve, wherein the other end of the third stop valve is connected to the third end of the second three-way valve through a circulating water pipeline via a single-effect absorption heat pump system, the first end of the second three-way valve is connected to the first end of the third three-way valve, and the second end of the second three-way valve is connected to the third end of the fourth three-way valve through a circulating water pipeline via a double-effect absorption heat pump system; the other end of the third stop valve is also connected to the first end of the fourth three-way valve, and the second end of the fourth three-way valve is also connected to the third end of the fifth three-way valve; the other end of the first stop valve is also connected to the first end of the fifth three-way valve, the second end of the fifth three-way valve is connected to the second end of the third three-way valve through a circulating water pipeline via a low-temperature waste heat management system, and the third end of the third three-way valve is connected to the third end of the first three-way valve, wherein, during the heating cycle, the method also includes : respectively control the second end of the second three-way valve to be connected with the first end of the second three-way valve, the first end of the third three-way valve to be connected with the second end of the third three-way valve, the second end of the fifth three-way valve to be connected with the third end of the fifth three-way valve, the first end of the fourth three-way valve to be connected with the second end of the fourth three-way valve, the first end of the fourth three-way valve to be connected with the third end of the fourth three-way valve, and the third end of the second three-way valve to be connected with the first end of the second three-way valve; a first waste heat utilization loop is formed between the double-effect absorption heat pump system, the fourth three-way valve, the fifth three-way valve, the low-temperature waste heat management system, the third three-way valve and the second three-way valve; a second waste heat utilization loop is formed between the single-effect absorption heat pump system, the fourth three-way valve, the fifth three-way valve, the low-temperature waste heat management system, the third three-way valve and the second three-way valve; a low-temperature heat source is provided to the double-effect absorption heat pump system and the single-effect absorption heat pump system through the first waste heat utilization loop and the second waste heat utilization loop.

[0009] In a possible embodiment, the waste heat management system includes an auxiliary equipment heat exchanger, a cold source heat exchanger and a second circulation pump, wherein, during the heat supply cycle, the method further includes: absorbing heat from the nuclear power production auxiliary equipment through the auxiliary heat exchanger to transfer the production waste heat corresponding to the nuclear power production auxiliary equipment to the circulating water in the waste heat management system; the circulating water output by the auxiliary heat exchanger flows into the fourth three-way valve via the fifth three-way valve, and is divided into two paths of circulating water through the fourth three-way valve, one of which releases heat through the evaporator in the double-effect absorption heat pump system to provide a low-temperature heat source for the double-effect absorption heat pump system, and the other releases heat through the circulation The circulating water releases heat through the evaporator of the single-effect absorption heat pump system, providing a low-temperature heat source for the single-effect absorption heat pump system; the two circulating water outputs from the evaporator in the double-effect absorption heat pump system and the evaporator in the single-effect absorption heat pump system are received and merged through the second three-way valve, and input into the cold source heat exchanger through the third three-way valve for heat release, so as to discharge the unused excess heat in the circulating water through the cold source heat exchanger; the circulating water output from the cold source heat exchanger is connected to the auxiliary equipment heat exchanger again in the form of circulating return water through the second circulating pump, so as to complete the energy supply process of the low-temperature waste heat management system to the double-effect absorption heat pump system and the single-effect absorption heat pump system.

[0010] In a possible embodiment, the cascade waste heat utilization system also includes a third circulation pump, wherein executing the cooling cycle also includes: respectively controlling the third stop valve and the fourth stop valve to open and the first stop valve to close; respectively connecting the second end of the second three-way valve and the third end of the second three-way valve and connecting the first end of the fourth three-way valve and the third end of the fourth three-way valve; controlling the cooling water input from the cooling return water end to be input into the third stop valve through the third circulation pump; dividing the cooling water into two paths, and respectively delivering one of the cooling water paths to the evaporator in the double-effect absorption heat pump system through the fourth three-way valve for heat release, and directly delivering the other cooling water path to the evaporator in the single-effect absorption heat pump system for heat release; outputting the cooling water output from the evaporator in the double-effect absorption heat pump system to the cold end through the second three-way valve through the fourth throttle valve; outputting the cooling water output from the evaporator in the single-effect absorption heat pump system to the cold end through the fourth throttle valve.

[0011] In a possible embodiment, executing the cooling cycle also includes: respectively connecting the first end of the fifth three-way valve and the second end of the fifth three-way valve, connecting the second end of the fifth three-way valve and the third end of the fifth three-way valve, connecting the first end and the third end of the first three-way valve, connecting the third end of the third three-way valve and the second end of the third three-way valve; forming a first heat release loop between the low-temperature waste heat management system, the fifth three-way valve, the double-effect absorption heat pump system, the first three-way valve and the third three-way valve; forming a second heat release loop between the low-temperature waste heat management system, the fifth three-way valve, the single-effect absorption heat pump system, the first three-way valve and the third three-way valve; and utilizing the first heat release loop and the second heat release loop to dissipate the waste heat generated by the auxiliary equipment, the double-effect absorption heat pump system and the single-effect absorption heat pump system.

[0012] In a possible implementation, the waste heat management system includes an auxiliary equipment heat exchanger, a cold source heat exchanger and a third circulation pump, wherein, in the cooling cycle, the first heat release loop and the second heat release loop are used to dissipate the waste heat generated by the auxiliary equipment, the double-effect absorption heat pump system and the single-effect absorption heat pump system, including: absorbing heat from the nuclear power production auxiliary equipment through the auxiliary equipment heat exchanger to transfer the production waste heat corresponding to the nuclear power production auxiliary equipment to the circulating water in the waste heat management system; inputting the circulating water output by the auxiliary equipment heat exchanger into the fifth three-way valve; and inputting the circulating water into the fifth three-way valve via the fifth three-way valve. The circulating water of the three-way valve is divided into two paths, one of which absorbs heat through the absorber and condenser in the double-effect absorption heat pump system in turn, and the other circulating water absorbs heat through the absorber and condenser in the single-effect absorption heat pump system; the two circulating waters output by the double-effect absorption heat pump system and the single-effect absorption heat pump system are received and merged through the first three-way valve, and input into the cold source heat exchanger through the first three-way valve and the third three-way valve for heat release, so as to discharge the heat carried in the circulating water through the cold source heat exchanger; the circulating water output by the cold source heat exchanger is connected to the auxiliary equipment heat exchanger again in the form of circulating return water through the second circulating pump.

[0013] In a possible implementation, the double-effect absorption heat pump system includes a first high-pressure generator, a first solution heat exchanger, a first absorber, a low-pressure generator, a first condenser, a first evaporator, a first throttle valve, a second throttle valve, a third throttle valve, a fourth throttle valve, a first solution pump, and a second solution pump. The first high-pressure generator is connected to the auxiliary steam provided by the nuclear power plant equipment through a steam pipeline. The first high-pressure generator is connected to the first absorber through a solution pipeline in sequence through the first solution pump, the first solution heat exchanger, and the second solution pump. The first high-pressure generator also passes through the solution pipeline in sequence through the first throttle valve, the first solution heat exchanger, and the second throttle valve. The first absorber is connected, the first high-pressure generator, the low-pressure generator, the third throttle valve and the first condenser are connected in sequence through a solution pipeline, the low-pressure generator is connected to the solution pipeline between the first solution heat exchanger and the first solution pump, the low-pressure generator is also connected to the solution pipeline between the first throttle valve and the first solution heat exchanger, the first condenser is connected to the first evaporator through the solution pipeline via the fourth throttle valve, and the first evaporator and the first absorber are connected through a steam pipeline, wherein the double-effect absorption heat pump system absorbs auxiliary steam heat in the following manner: using the refrigerant solution in the first high-pressure generator to absorb the auxiliary steam heat Generate high-pressure refrigerator steam and concentrated refrigerant solution, and respectively transport the high-pressure refrigerator steam to the low-pressure generator and the auxiliary steam after heat release to the single-effect absorption heat pump system; the high-pressure refrigerator steam releases heat to the circulating water flowing into the double-effect absorption heat pump system through the low-pressure generator, the third throttle valve, the first condenser, and the fourth throttle valve in sequence, to obtain liquid refrigerant and input it into the first evaporator; utilize the low-temperature heat source provided by the low-temperature waste heat management system and the first evaporator to absorb heat and evaporate the liquid refrigerant to generate gaseous refrigerant that flows into the first absorber; absorb the gaseous refrigerant through the absorbent in the first absorber to obtain a dilute refrigerant solution The heat generated in the absorption process is released to the circulating water flowing into the double-effect absorption heat pump system; the dilute refrigerant solution is pressurized by the second solution pump and then input into the first solution heat exchanger. After the dilute refrigerant solution is initially absorbed by the first solution heat exchanger, a part of the dilute refrigerant solution is input into the low-pressure generator, and the other part of the dilute refrigerant solution is pressurized by the first solution pump and then transported to the first high-pressure generator; the concentrated refrigerant solution obtained after the first high-pressure generator is generated is reduced in pressure by the first throttle valve and mixed with the concentrated refrigerant solution flowing out of the low-pressure generator, releases heat through the first solution heat exchanger, and is reduced in pressure again by the second throttle valve and then input into the first absorber.

[0014] In a possible implementation, the single-effect absorption heat pump system includes a second high-pressure generator, a second solution heat exchanger, a second absorber, a second condenser, a second evaporator, a fifth throttle valve, a sixth throttle valve and a third solution pump. The second high-pressure generator is connected to the auxiliary steam after heat release by the double-effect absorption heat pump system through a steam pipeline. The second high-pressure generator is connected to the second absorber through a solution pipeline in sequence through the second solution heat exchanger and the third solution pump. The second high-pressure generator is also connected to the second absorber through a solution pipeline in sequence through the second solution heat exchanger and the fifth throttle valve. The second high-pressure generator is connected to the second condenser through a solution pipeline. The second condenser is connected to the second evaporator through a solution pipeline through the sixth throttle valve. The second evaporator and the second absorber are connected through a steam pipeline. The hot water supply is connected to the circulating water pipeline of the second absorber through the first stop valve and the first circulating pump. The solution pipeline in the second absorber is also connected to the first end of the first three-way valve through the second condenser. The heat of auxiliary steam is absorbed in the following manner: the refrigerant solution in the second high-pressure generator absorbs the heat of auxiliary steam transferred by the double-effect absorption heat pump system to generate high-pressure refrigerator steam and concentrated refrigerant solution; the high-pressure refrigerator steam is transported to the second condenser; after the high-pressure refrigerator steam is released heat by the second condenser, liquid refrigerant is obtained and input into the second evaporator; the liquid refrigerant is evaporated by absorbing heat by the low-temperature heat source provided by the low-temperature waste heat management system and the second evaporator to generate gaseous refrigerant flowing into the second absorber; the gaseous refrigerant is absorbed by the absorbent in the second absorber to obtain a dilute refrigerant solution, and the heat generated in the absorption process is released to the circulating water flowing into the single-effect absorption heat pump system; the dilute refrigerant solution is pressurized by the third solution pump and input into the second solution heat exchanger; the dilute refrigerant solution is absorbed heat by the second solution heat exchanger and then transported to the second high-pressure generator; the concentrated refrigerant solution obtained after the second high-pressure generator is generated is successively released heat through the second solution heat exchanger and reduced pressure by the fifth throttle valve and then input into the second absorber.

[0015] On the second aspect, an embodiment of the present application also provides a nuclear power plant heat source management system, which includes a combined heat and cooling system and a low-temperature waste heat management system. The combined heat and cooling system includes a double-effect absorption heat pump system, a single-effect absorption heat pump system, a first heat exchanger and a cascade waste heat utilization system. Auxiliary steam is connected to the steam output end via a steam pipeline via the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger. The nuclear power plant heat source management system also includes a processor, which is applied to the thermal management method based on nuclear power plant equipment provided in any of the above embodiments.

[0016] The embodiment of the present application provides a thermal management method based on nuclear power plant equipment and a nuclear power plant heat source management system, including: controlling the cascade waste heat utilization system to switch to a heating operation state, absorbing the temperature of auxiliary equipment through a low-temperature waste heat management system to provide a low-temperature heat source for a double-effect absorption heat pump system and a single-effect absorption heat pump system respectively, using the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger to step-by-step absorb auxiliary waste heat to provide heat for hot water supply, and completing a heating cycle; controlling the cascade waste heat utilization system to switch to a cooling operation state, using the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger to step-by-step absorb auxiliary waste heat and circulate heat through the low-temperature waste heat management system to complete a cooling cycle. The present application uses a double-effect absorption system, a single-effect absorption system and a heat exchange combination to gradiently utilize the internal energy of nuclear power plant steam, improve energy utilization efficiency, and avoid resource waste.

[0017] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application 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 paying creative work.

[0019] Figure 1 A flow chart of a thermal management method based on nuclear power plant equipment provided by an embodiment of the present application is shown;

[0020] Figure 2 A schematic structural diagram of a nuclear power plant heat source management system provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0021] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0022] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0023] Nuclear power is a zero-CO2 emission power generation method. In a nuclear reactor, the energy generated by nuclear fission is converted into internal energy and absorbed by cooling water. The cooling water that has absorbed a large amount of energy is converted into high-temperature and high-pressure steam through a steam generator and passed into a steam turbine generator. In the steam turbine, the steam drives the turbine blades to generate electricity, converting internal energy into electrical energy. The steam flowing out after power generation is generally at a temperature of more than 150°C, and still has a high utilization value.

[0024] The existing utilization method is generally to provide 60℃-70℃ hot water for heating to reactor buildings, fuel buildings, etc. through heat exchange with the hot water production and distribution system (SES), so as to ensure the internal temperature of the building under cold climate conditions and improve the working comfort of maintenance personnel. In hot climate conditions, the SES system needs to provide chilled water of about 7℃ to the relay room, DC distribution room, etc., so as to promptly remove the heat generated by the operation of key equipment and ensure the safe and normal operation of the nuclear power plant circuit. The refrigeration process of the existing technology needs to be completed by another additional compression refrigeration unit, that is, the existing technology needs to rely on two independent cooling systems and heating systems to achieve cooling and heating under cold and hot climate conditions respectively, so as to meet the different temperature requirements in the nuclear power plant area.

[0025] And the equipment used to build a nuclear power plant is mainly divided into three categories, namely nuclear island equipment, conventional island equipment and auxiliary equipment. The heat generated by the operation of the auxiliary equipment is taken out of the conventional island closed cooling water system through a plate heat exchanger and discharged into the seawater of the open circulating cooling water system. In the cold season, the equipment used to build a nuclear power plant is mainly divided into three categories, namely nuclear island equipment, conventional island equipment and auxiliary equipment. The heat generated by the operation of the auxiliary equipment is taken out of the conventional island closed cooling water system (SRI) through a plate heat exchanger and discharged into the seawater of the open circulating cooling water system. In the cold season, the waste heat temperature of the SRI system fluctuates between 25℃-35℃, which is a low-temperature waste heat that is directly discharged into the environment. The waste heat temperature fluctuates between 25℃-35℃, which is a low-temperature waste heat that is directly discharged into the environment.

[0026] The existing thermal management system of nuclear power plant equipment has the problems of complex structure and low energy utilization, which are specifically reflected in:

[0027] (1) During the heating process, auxiliary steam exceeding 150°C is used to produce hot water at 60-70°C by direct heat exchange. Due to the temperature difference in heat exchange, the auxiliary steam generates a large amount of loss;

[0028] (2) Using steam through traditional direct heat exchange, due to the small temperature drop of steam, the heat of the steam after heat exchange cannot be used, further resulting in energy waste;

[0029] (3) The low-temperature waste heat generated by the auxiliary equipment is directly discharged into the environment through the conventional island closed cooling water system, which not only affects the marine environment but also generates energy waste.

[0030] Based on this, the embodiment of the present application provides a thermal management method based on nuclear power plant equipment and a nuclear power plant heat source management system, which uses a double-effect absorption system, a single-effect absorption system and a heat exchange combination to gradiently utilize the steam internal energy of the nuclear power plant, improve energy utilization efficiency, and avoid resource waste, as follows:

[0031] See also Figure 1 , Figure 1 A flow chart of a thermal management method based on nuclear power plant equipment provided by an embodiment of the present application is shown. Figure 1 As shown, the method provided in the embodiment of the present application is applied to the heat source management system of a nuclear power plant.

[0032] Preferably, the heat source management system of the nuclear power plant includes a combined heat and cooling system and a low-temperature waste heat management system, the combined heat and cooling system includes a double-effect absorption heat pump system, a single-effect absorption heat pump system, a first heat exchanger and a cascade waste heat utilization system, and the auxiliary steam is connected to the steam output end through a steam pipeline via the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger.

[0033] The heating return water end uses a circulating water pipeline to connect to the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger respectively through the cascade waste heat utilization system. The double-effect absorption heat pump system and the single-effect absorption heat pump system use circulating water pipelines to connect to the heat-using end respectively through the cascade waste heat utilization system.

[0034] The cooling return water end uses a circulating water pipeline through a cascade waste heat utilization system to connect to a double-effect absorption heat pump system and a single-effect absorption heat pump system respectively. The double-effect absorption heat pump system and the single-effect absorption heat pump system use a circulating water pipeline through a cascade waste heat utilization system to connect to the cold end respectively.

[0035] The low-temperature waste heat management system is connected to the cascade waste heat utilization system to access the double-effect absorption heat pump system and the single-effect absorption heat pump system through the cascade waste heat utilization system.

[0036] like Figure 1 As shown, the method includes:

[0037] S100, determining that the current ambient temperature is less than a first temperature threshold, then controlling the cascade waste heat utilization system to switch to a heating operation state, so that the hot water input from the heating return water end is divided into three paths and flows into the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger respectively.

[0038] S200, utilizing auxiliary steam to release heat from hot water in a stepwise manner through a double-effect absorption heat pump system, a single-effect absorption heat pump system and a first heat exchanger, and summing up the three hot water supplies and outputting them to a heat-using end.

[0039] S300, absorbs the waste heat generated by the production auxiliary equipment in the nuclear power plant through the low-temperature waste heat management system, and provides low-temperature heat source for the double-effect absorption heat pump system and the single-effect absorption heat pump system respectively, completing the heating cycle.

[0040] S400, if it is determined that the current ambient temperature is greater than or equal to the first temperature threshold, the cascade waste heat utilization system is controlled to switch to a cooling operation state, so that the cooling water input from the cooling return water end flows into the double-effect absorption heat pump system and the single-effect absorption heat pump system in two ways.

[0041] S500, gradiently utilizing auxiliary steam to provide a high-temperature heat source for the double-effect absorption heat pump system and the single-effect absorption heat pump system, so that the double-effect absorption heat pump system and the single-effect absorption heat pump system absorb heat from the cooling water.

[0042] S600, the two routes of cold water output after heat release from the double-effect absorption heat pump system and the single-effect absorption heat pump system are combined and output to a cold end.

[0043] S700, using the low-temperature waste heat management system to dissipate the waste heat generated by auxiliary equipment, the double-effect absorption heat pump system and the single-effect absorption heat pump system to complete the cooling cycle.

[0044] In steps S100 to S600 provided in the present application, the current ambient temperature or required temperature in the target nuclear power plant building is first detected. The target nuclear power plant building is a nuclear power plant building that needs to be cooled or heated. Then, based on the current ambient temperature or required temperature, it is determined to execute the cooling cycle or heating cycle process. Specifically, the cascade waste heat utilization system can realize the switching of the nuclear power plant heat source management system in the cooling cycle or the heating cycle. On the one hand, in the heating process, the nuclear power plant heat source management system provided by the present application uses the auxiliary steam as a double-effect absorption heat pump, a single-effect absorption heat pump and a high-temperature heat source for the heat exchange process in turn, so as to gradiently utilize the auxiliary steam waste heat generated by the nuclear power plant through the double-effect absorption heat pump, the single-effect absorption heat pump and the first heat exchanger, and respectively recover the sensible heat of the steam condensation heat, the high-temperature condensed water and the medium-temperature condensed water, thereby improving the utilization efficiency of the high-temperature heat source provided by the auxiliary steam and reducing loss.

[0045] In addition, during the refrigeration process, the nuclear power plant heat source management system provided by the present application gradiently utilizes the condensation heat and sensible heat of auxiliary steam as the high-temperature heat source for the double-effect absorption refrigeration cycle and the single-effect absorption refrigeration cycle, so that the double-effect absorption heat pump system and the single-effect absorption heat pump system absorb heat from the cooling water under the drive of the high-temperature heat source, thereby cooling the cooling water and reducing power consumption. In addition, the low-temperature waste heat management system not only dissipates the corresponding waste heat for the auxiliary equipment, but also dissipates the heat for the internal circulation of the double-effect absorption heat pump system and the single-effect absorption heat pump system.

[0046] See also Figure 2 , Figure 2 The schematic diagram of the structure of a nuclear power plant heat source management system provided by the embodiment of the present application is shown. Figure 2 As shown, the combined cooling and heating system further includes a first circulation pump R1.

[0047] The cascade waste heat utilization system includes a first stop valve V1, a second stop valve V2, a third stop valve V3, a fourth stop valve V4 and a first three-way valve Q1, a second three-way valve Q2, a third three-way valve Q3, a fourth three-way valve Q4 and a fifth three-way valve Q5, and a third circulation pump R3.

[0048] The waste heat management system includes an auxiliary equipment heat exchanger 13, a cold source heat exchanger 14 and a second circulation pump R2.

[0049] The double-effect absorption heat pump system includes a first high-pressure generator 1, a first solution heat exchanger 2, a first absorber 3, a low-pressure generator 4, a first condenser 5, a first evaporator 6, a first throttle valve S1, a second throttle valve S2, a third throttle valve S3, a fourth throttle valve S4, a first solution pump P1 and a second solution pump P2.

[0050] The single-effect absorption heat pump system includes a second high-pressure generator 7, a second solution heat exchanger 8, a second absorber 9, a second condenser 10, a second evaporator 11, a fifth throttle valve S5, a sixth throttle valve S6 and a third solution pump P3.

[0051] One end of the first stop valve V1 is connected to the heating return water end C, and the other end of the first stop valve V1 is connected to the first end m of the first three-way valve Q1 through a circulating water pipeline via the first absorber 3 and the first condenser 5 in the double-effect absorption heat pump system.

[0052] The other end of the first stop valve V1 is also connected to the first end m of the first three-way valve Q1 through a circulating water pipeline via a second absorber 9 and a second condenser 10 in the single-effect absorption heat pump system.

[0053] The other end of the first stop valve V1 is also connected to the first end m of the first three-way valve Q1 through a circulating water pipeline via the second stop valve V2 and the first heat exchanger 12 .

[0054] The second end o of the first three-way valve Q1 is connected to the hot end D, one end of the third stop valve V3 is connected to the cold return water through the third circulating pump, the other end of the third stop valve V3 is connected to one end of the fourth stop valve V4 through the circulating water pipeline via the second evaporator in the single-effect absorption heat pump system, and the other end of the fourth stop valve V4 is connected to the cold end F.

[0055] In the present application, the auxiliary steam generated after nuclear power generation is input through the high-temperature heat source input terminal A, and then flows into the steam recovery terminal B through the steam pipeline in sequence through the first high-pressure generator 1, the second high-pressure generator 7 and the first heat exchanger 12.

[0056] The nuclear power plant heat source management system of the present application includes the following methods in the process of executing the heating cycle:

[0057] The first stop valve V1 and the second stop valve V2 are controlled to be opened, the third stop valve V3 and the fourth stop valve V4 are controlled to be closed, the first end m of the first three-way valve Q1 and the second end o of the first three-way valve Q1 are controlled to be connected, and the hot water connected by the heating return water end C is controlled to be input into the first circulation pump R1 through the first stop valve V1, so that under the action of the first circulation pump R1, the hot water is divided into three routes (including the first route of hot water supply, the second route of hot water supply and the third route of hot water supply) and respectively input into the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger 12.

[0058] Specifically, the auxiliary steam input from the high-temperature heat source input terminal A first enters the first high-pressure generator in the double-effect absorption heat pump system, so as to undergo the first-stage heat absorption treatment through the first high-pressure generator, so as to provide a high-temperature heat source for the heating cycle of the double-effect absorption heat pump system. The first hot water output from the first circulation pump R1 absorbs heat through the first absorber 3 and the first condenser 5, and then is input to the first end m of the first three-way valve.

[0059] The auxiliary steam output by the first high-pressure generator 7 is input to the second high-pressure generator 7 in the single-effect absorption heat pump system, so as to be subjected to a second-stage heat absorption treatment by the second high-pressure generator 7, so as to provide a high-temperature heat source for the heating cycle of the single-effect absorption heat pump system. The second hot water output by the first circulation pump R1 absorbs heat through the second absorber 9 and the second condenser 10, and is then input to the first end m of the first three-way valve Q1.

[0060] The auxiliary steam output by the second high-pressure generator 7 is input into the first heat exchanger 12. The third hot water output by the first circulating pump R1 is input into the first heat exchanger 12 via the second stop valve V2, and then directly exchanges heat with the auxiliary steam input into the first heat exchanger 12 to complete the third-stage heat absorption treatment of the auxiliary steam. The auxiliary steam after the third-stage heat absorption treatment is input into the steam recovery end B through the steam pipeline, and the hot water output by the first heat exchanger is input into the first end m of the first three-way valve Q1 through the circulating water pipeline.

[0061] The first condenser 5, the second condenser 10 and the three-way hot water after heat absorption are integrated and connected to the hot end D through the first end m of the first three-way valve Q1 and the second end n of the first three-way valve Q1.

[0062] In a preferred embodiment, if Figure 2 As shown, the other end of the third stop valve V3 is connected to the third end e of the second three-way valve Q2 through the circulating water pipeline via the second evaporator 11 in the single-effect absorption heat pump system, the first end f of the second three-way valve Q2 is connected to the first end g of the third three-way valve Q3, and the second end d of the second three-way valve Q2 is connected to the third end c of the fourth three-way valve Q4 through the circulating water pipeline via the first evaporator 6 in the double-effect absorption heat pump system.

[0063] The other end of the third stop valve V3 is also connected to the first end a of the fourth three-way valve Q4 , and the second end b of the fourth three-way valve Q4 is also connected to the third end k of the fifth three-way valve Q5 .

[0064] The other end of the first stop valve V1 is also connected to the first end l of the fifth three-way valve Q5, the second end j of the fifth three-way valve Q5 is connected to the second end i of the third three-way valve Q3 through the circulating water pipeline via the auxiliary equipment heat exchanger 13, the second circulating pump R2 and the cold source heat exchanger 14 in the low-temperature waste heat management system, and the third end h of the third three-way valve Q3 is connected to the third end n of the first three-way valve Q1.

[0065] In a preferred embodiment, the nuclear power plant heat source management system of the present application further includes the following methods during the execution of the heating cycle:

[0066] The second end d of the second three-way valve Q2 and the first end f of the second three-way valve Q2, the first end g of the third three-way valve Q3 and the second end i of the third three-way valve Q3, the second end j of the fifth three-way valve Q5 and the third end k of the fifth three-way valve Q5, the first end a of the fourth three-way valve Q4 and the second end b of the fourth three-way valve Q4, the first end a of the fourth three-way valve Q4 and the third end c of the fourth three-way valve Q4, the third end e of the second three-way valve Q2 and the first end f of the second three-way valve Q2 are connected.

[0067] A first waste heat utilization loop is formed between the first evaporator 6, the fourth three-way valve Q4, the fifth three-way valve Q5, the auxiliary equipment heat exchanger 13, the second circulation pump R2, the cold source heat exchanger 14, the third three-way valve Q3 and the second three-way valve Q2.

[0068] A second waste heat utilization loop is formed between the second evaporator 11, the fourth three-way valve, the fifth three-way valve, the auxiliary equipment heat exchanger 13, the second circulation pump R2, the cold source heat exchanger 14, the third three-way valve Q3 and the second three-way valve Q2.

[0069] A low-temperature heat source is provided to the double-effect absorption heat pump system and the single-effect absorption heat pump system through the first waste heat utilization loop and the second waste heat utilization loop.

[0070] In a specific embodiment, the step of providing a low-temperature heat source to a double-effect absorption heat pump system and a single-effect absorption heat pump system through a first waste heat utilization loop and a second waste heat utilization loop includes:

[0071] Driven by the second circulating pump P2, the circulating water in the low-temperature waste heat management system absorbs heat from the nuclear power production auxiliary equipment through the auxiliary heat exchanger 13. The circulating water that absorbs the waste heat of the auxiliary equipment flows into the second end b of the fourth three-way valve Q4 via the second end j and the third end k of the fifth three-way valve Q5.

[0072] The fourth three-way valve Q4 divides the circulating water into two paths, one of which is output through the third end c of the fourth three-way valve Q4 to the first evaporator 6 in the double-effect absorption heat pump system to release heat, providing a low-temperature heat source for the double-effect absorption heat pump system, and the other is output through the first end a of the fourth three-way valve Q4 to the second evaporator 11 in the single-effect absorption heat pump system to release heat, providing a low-temperature heat source for the single-effect absorption heat pump system.

[0073] One of the circulating water paths is input to the second end d of the second three-way valve Q3 after releasing heat through the first evaporator 6, and the other circulating water path is input to the second end d of the second three-way valve Q3 after releasing heat through the second evaporator 11. The two circulating water paths are merged at the second end d of the second three-way valve Q2, and are input to the cold source heat exchanger 14 through the first end f of the second three-way valve Q2, the first end g of the third three-way valve Q3 and the second end i of the third three-way valve to release heat, so as to discharge the unused excess heat in the circulating water through the cold source heat exchanger 14, and the circulating water after heat exchange treatment by the cold source heat exchanger 14 is connected to the auxiliary equipment heat exchanger 13 again in the form of circulating return water through the second circulating pump R2, so as to complete the energy supply process of the low-temperature waste heat management system to the double-effect absorption heat pump system and the single-effect absorption heat pump system.

[0074] It can be seen that the thermal management method provided by the present application, during the heating cycle, on the one hand, uses the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger to stepwise utilize the latent heat and sensible heat of the auxiliary steam to release heat to the generator in the double-effect absorption heat pump system and the single-effect absorption heat pump system, thereby driving the heat pump system to operate, thereby achieving the purpose of reducing heat loss and expanding heat, and the gradient utilization method reduces the return water temperature of the auxiliary steam, reducing the high-temperature heat exchange process. loss.

[0075] On the other hand, through the low-temperature thermal management system, part of the low-temperature waste heat generated by the auxiliary equipment can be absorbed by the combined heat and cold supply system, which can reduce the amount of heat discharged by the auxiliary equipment to the cold source heat exchanger, avoid waste of resources and damage to the environment.

[0076] The nuclear power plant heat source management system of the present application includes the following methods in the process of executing the cooling cycle:

[0077] The third stop valve V3 and the fourth stop valve V4 are controlled to open and the first stop valve V1 is closed, respectively connecting the second end d of the second three-way valve Q2 and the third end e of the second three-way valve Q2, and connecting the first end a of the fourth three-way valve Q4 and the third end c of the fourth three-way valve Q4.

[0078] The cooling water input from the cooling return water end E is controlled to be input into the third stop valve V3 under the action of the third circulation pump, and the cooling water output from the third stop valve V3 is divided into two paths, one of which is transported to the first evaporator 6 through the first end a of the fourth three-way valve Q4 and the third end c of the fourth three-way valve for heat release, and the other is directly transported to the second evaporator 11 for heat release.

[0079] The cold water output after absorbing heat in the first evaporator 6 is received through the second end d of the second three-way valve Q2, and then output to one end of the fourth throttle valve V4 through the third end e of the second three-way valve Q2, and is mixed with the cold water output from the second evaporator 11 and then transported to the cold end through the fourth throttle valve V4.

[0080] In a specific embodiment, the cooling cycle further comprises:

[0081] The first end l of the fifth three-way valve Q5 and the second end j of the fifth three-way valve Q5, the second end j of the fifth three-way valve Q5 and the third end k of the fifth three-way valve Q5, the first end m and the third end n of the first three-way valve Q1, the third end h of the third three-way valve Q3 and the second end i of the third three-way valve Q3 are connected respectively.

[0082] A first heat release loop is formed between the auxiliary equipment heat exchanger 13, the fifth three-way valve Q5, the first absorber 3 in the double-effect absorption heat pump system, the first condenser 5, the first three-way valve Q1, the third three-way valve Q2 and the cold source heat exchanger 14.

[0083] A second heat release loop is formed between the auxiliary equipment heat exchanger 13, the fifth three-way valve Q5, the second absorber 9 in the single-effect absorption heat pump system, the second condenser 10, the first three-way valve Q1, the third three-way valve Q2 and the cold source heat exchanger 14.

[0084] The first heat release loop and the second heat release loop are used to dissipate waste heat generated by auxiliary equipment, a double-effect absorption heat pump system and a single-effect absorption heat pump system.

[0085] In a specific embodiment, the first heat release loop and the second heat release loop are used to dissipate waste heat generated by auxiliary equipment, a double-effect absorption heat pump system, and a single-effect absorption heat pump system, including:

[0086] The auxiliary equipment heat exchanger 13 absorbs heat from the nuclear power production auxiliary equipment to transfer the production waste heat corresponding to the nuclear power production auxiliary equipment to the circulating water in the waste heat management system, and the circulating water output by the auxiliary equipment heat exchanger 13 is input to the second end j of the fifth three-way valve Q5. The circulating water input to the fifth three-way valve Q5 is divided into two paths through the fifth three-way valve Q5, one of which is sequentially absorbed by the first end i of the fifth three-way valve Q5, the first absorber 3 and the first condenser 5, and the other is sequentially absorbed by the first end i of the fifth three-way valve Q5, the single-effect absorption heat pump system, and the second end i of the single-effect absorption heat pump system. The second absorber 9 and the second condenser 10 absorb heat, receive and merge the two circulating water output by the first condenser 5 and the second condenser 10 through the first end m of the first three-way valve Q1, and sequentially input the two circulating waters into the cold source heat exchanger 14 through the third end n of the first three-way valve, the third end h of the third three-way valve Q3, and the second end i of the third three-way valve Q3 to release heat, so as to discharge the heat carried in the circulating water through the cold source heat exchanger 14, and the circulating water output after the cold source heat exchanger 14 releases heat is again connected to the auxiliary equipment heat exchanger 13 in the form of circulating return water through the second circulating pump R2.

[0087] Specifically, the thermal management method provided in the present application reduces the refrigeration energy consumption through the double-effect absorption heat pump system and the single-effect absorption heat pump system during the cooling cycle, and the auxiliary steam releases heat to the generator inside the single-effect and double-effect absorption heat pump systems to drive the single-effect and double-effect absorption heat pump systems to operate. The cooling return water is divided into two paths, which release heat and cool down the first evaporator 6 and the second evaporator 11 respectively for the refrigeration cycle. In addition, the waste heat generated by the absorber and condenser inside the double-effect absorption heat pump system and the single-effect absorption heat pump system can be discharged to the cold source through the low-temperature thermal management system, thereby realizing effective heat dissipation of the double-effect absorption heat pump system and the single-effect absorption heat pump system.

[0088] In a preferred embodiment, for a double-effect absorption heat pump system, the first high-pressure generator 1 is connected to the auxiliary steam provided by the nuclear power plant equipment through a steam pipeline, and the first high-pressure generator 1 is connected to the first absorber 3 through a solution pipeline in sequence through the first solution pump P1, the first solution heat exchanger 2 and the second solution pump P2. The first high-pressure generator 1 is also connected to the first absorber 3 through a solution pipeline in sequence through the first throttle valve S1, the first solution heat exchanger 2 and the second throttle valve S2. The first high-pressure generator 1, the low-pressure generator 4, the third throttle valve S3 and the first condenser 5 are connected in sequence through a solution pipeline, the low-pressure generator 4 is connected to the solution pipeline between the first solution heat exchanger 2 and the first solution pump P1, and the low-pressure generator 4 is also connected to the solution pipeline between the first throttle valve S1 and the first solution heat exchanger 2. The first condenser 5 is connected to the first evaporator 6 through the solution pipeline through the fourth throttle valve S4, and the first evaporator 6 and the first absorber 3 are connected through a steam pipeline.

[0089] In a specific embodiment, the double-effect absorption heat pump system absorbs auxiliary steam heat in the following manner:

[0090] The refrigerant solution in the first high-pressure generator 1 absorbs the heat of the auxiliary steam to generate high-pressure refrigerator steam and concentrated refrigerant solution, and the high-pressure refrigerator steam is transported to the low-pressure generator 4 and the auxiliary steam after heat release is transported to the second high-pressure generator 7 in the single-effect absorption heat pump system.

[0091] The high-pressure refrigerator steam flows into the low-pressure generator 4, the third throttle valve S3, and the first condenser 5 in sequence to release heat to the circulating water flowing into the double-effect absorption heat pump system. The liquid refrigerant obtained after the heat release treatment in the first condenser 5 is input into the first evaporator 6 through the fourth throttle valve S4. In the first evaporator 6, the liquid refrigerant is absorbed and evaporated by the low-temperature heat source provided by the low-temperature waste heat management system to generate a gaseous refrigerant that flows into the first absorber 3.

[0092] The absorbent in the first absorber 3 absorbs the gaseous refrigerant to obtain a dilute refrigerant solution, and the heat generated in the absorption process is released to the circulating water flowing into the double-effect absorption heat pump system. The dilute refrigerant solution is pressurized by the second solution pump P2 and then input into the first solution heat exchanger 2. After the first solution heat exchanger 2 preliminarily absorbs heat from the dilute refrigerant solution, a part of the dilute refrigerant solution is input into the low-pressure generator 4, and the other part of the dilute refrigerant solution is pressurized by the first solution pump P1 and then transported to the first high-pressure generator 1.

[0093] The concentrated refrigerant solution obtained after the first high-pressure generator 1 is reduced in pressure by the first throttle valve S1 and mixed with the concentrated refrigerant solution flowing out of the low-pressure generator 4, releases heat through the first solution heat exchanger 2, and is reduced in pressure again by the second throttle valve S2 and then input into the first absorber 3.

[0094] In another preferred embodiment, the single-effect absorption heat pump system includes a second high-pressure generator 7, a second solution heat exchanger 8, a second absorber 9, a second condenser 10, a second evaporator 11, a fifth throttle valve S5, a sixth throttle valve S6 and a third solution pump P3.

[0095] The second high-pressure generator 7 is connected to the auxiliary steam after heat release by the first high-pressure generator 1 through a steam pipeline. The second high-pressure generator 7 is connected to the second absorber 9 through a solution pipeline in sequence through the second solution heat exchanger 8 and the third solution pump P3. The second high-pressure generator 7 is also connected to the second absorber 9 through a solution pipeline in sequence through the second solution heat exchanger 8 and the fifth throttle valve V5. The second high-pressure generator 7 is connected to the second condenser 10 through a solution pipeline. The second condenser 10 is connected to the second evaporator 11 through a solution pipeline through the sixth throttle valve V6. The second evaporator 11 is connected to the second absorber 9 through a steam pipeline. The hot water supply is connected to the circulating water pipeline of the second absorber 9 through the first stop valve V1 and the first circulating pump R1. The solution pipeline in the second absorber 9 is also connected to the first end m of the first three-way valve Q1 through the second condenser 10.

[0096] In a specific embodiment, the single-effect absorption heat pump system absorbs auxiliary steam heat in the following manner:

[0097] The refrigerant solution in the second high-pressure generator 7 absorbs the auxiliary steam heat transferred from the first evaporator 6 to generate high-pressure refrigerator steam and concentrated refrigerant solution. The high-pressure refrigerator steam is transported to the second condenser 10. After the high-pressure refrigerator steam releases heat through the second condenser 10, liquid refrigerant is obtained and input into the second evaporator 11.

[0098] The low-temperature heat source provided by the low-temperature waste heat management system and the second evaporator 11 absorb heat from the liquid refrigerant and evaporate it to generate a gaseous refrigerant that flows into the second absorber 9. The absorbent in the second absorber 9 absorbs the gaseous refrigerant to obtain a dilute refrigerant solution. The heat generated in the absorption process is released to the circulating water flowing into the single-effect absorption heat pump system. The dilute refrigerant solution is pressurized by the third solution pump P3 and input into the second solution heat exchanger 8. The second solution heat exchanger 8 absorbs heat from the dilute refrigerant solution and then transports it to the second high-pressure generator 7. The concentrated refrigerant solution obtained after the second high-pressure generator 7 releases heat through the second solution heat exchanger 8 and is reduced in pressure by the fifth throttle valve V5 before being input into the second absorber 9.

[0099] In a preferred embodiment, the present application can replace and optimize the absorbent and refrigerant in a double-effect absorption heat pump system and a single-effect absorption heat pump system according to actual needs.

[0100] Preferably, the circulating working fluid in the cooling cycle for delivering cold to the cold end and the heating cycle for delivering heat to the hot end is usually water, which can be replaced by other working fluids according to actual operation needs.

[0101] Among them, when the current ambient temperature is lower than the freezing risk threshold, the circulating working fluid flowing in the low-temperature waste heat management system is replaced with antifreeze.

[0102] In a preferred embodiment, the nuclear power plant heat source management system provided in the present application also includes a processor, which executes the thermal management method provided in any of the above embodiments. Specifically, the processor can be connected to the cascade waste heat utilization system to control the switching of the states of each stop valve, three-way valve, solution pump, circulation pump and throttle valve in the cascade waste heat utilization system, thereby realizing the switching of the operating mode of the nuclear power plant heat source management system.

[0103] In another preferred embodiment, the internal operating pressure and operating temperature of the combined heat and cold supply system can be regulated by setting the solution concentration of the refrigerant pair of the double-effect absorption heat pump system and the single-effect absorption heat pump system, the circulation ratio and the mass flow distribution of the high and low pressure generators in the double-effect absorption heat pump system, that is, the optimal solution concentration, circulation ratio and flow distribution are obtained according to the required temperature, equipment operating pressure range and efficiency optimization calculation.

[0104] In a possible implementation, the cooling capacity and heating capacity of the system can be further designed by adjusting the solution volume, circulation rate and heat transfer rate of the heat exchanger in the double-effect absorption heat pump system and the single-effect absorption heat pump system.

[0105] Furthermore, in the combined cooling and heating system, the auxiliary steam undergoes an exothermic process in which it is cooled and condensed into high-temperature liquid water and then cooled again. The first high-pressure generator in the double-effect absorption heat pump system utilizes the heat released by the cooling and condensation process of the auxiliary steam. The second high-pressure generator and the first heat exchanger in the single-effect absorption heat pump system utilize the heat released by the first high-pressure generator in cooling the liquid water output after processing the auxiliary steam. The condensation temperature is controlled by adjusting the pressure of the auxiliary steam, thereby regulating the heat supply of the three driving heat sources.

[0106] In a preferred embodiment, the cooling cycle includes two cooling water branches from the cooling water return end E to the cooling end F, and the heating cycle includes three hot water branches from the heating water return end C to the hot end D. The present application can obtain different output powers of the cooling cycle by adjusting the flow distribution of each cooling water branch in the cooling water cycle, and obtain different output powers of the heating cycle by adjusting the flow distribution of each hot water supply branch in the hot water cycle.

[0107] Furthermore, in the combined cooling and heating system provided in the present application, the auxiliary steam heat supply is matched with the cooling cycle output power and the heating cycle output power respectively.

[0108] Specifically, during the heat cycle, the auxiliary steam heat distribution matches the heating output power of the three circuits of the double-effect energy absorption system, the single-effect energy absorption system and the first heat exchanger, and the return water temperature of the auxiliary steam circuit matches the heating cut-off temperature of the first heat exchanger.

[0109] During the cold cycle, the auxiliary steam heat distribution matches the cooling output power of the two circuits of the double-effect energy absorption system and the single-effect energy absorption system.

[0110] In a preferred embodiment, the combined cooling and heating system provided by the present application is matched with a low-temperature waste heat management system.

[0111] Specifically, during the heating process, the heat absorption efficiency and heat absorption temperature of the evaporator of the single-effect absorption heat pump system and the double-effect absorption heat pump system match the heating efficiency and heating temperature of the low-temperature waste heat management system.

[0112] During the cooling process, the total heat production of the auxiliary equipment heat exchanger, the absorber and the condenser in the single-effect absorption heat pump system and the double-effect absorption heat pump system matches the heat release of the cold source heat exchanger.

[0113] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. In the several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0114] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0115] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0116] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0117] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A thermal management method based on nuclear power plant equipment, characterized in that: The method is applied to a heat source management system of a nuclear power plant, wherein the heat source management system of the nuclear power plant includes a combined cooling and heating system and a low-temperature waste heat management system, wherein the combined cooling and heating system includes a double-effect absorption heat pump system, a single-effect absorption heat pump system, a first heat exchanger and a cascade waste heat utilization system, and the auxiliary steam is connected to the steam output end through a steam pipeline via the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger. Among them, the methods include: If it is determined that the current ambient temperature is less than the first temperature threshold, the cascade waste heat utilization system is controlled to switch to a heating operation state, so that the hot water input from the heating return water end is divided into three paths and flows into the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger respectively; The auxiliary steam is used to release the hot water in a step-by-step manner through the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger, and the three hot water supplies are output to the heat-using end in a combined manner; The waste heat generated by the production auxiliary equipment in the nuclear power plant is absorbed by the low-temperature waste heat management system, and low-temperature heat sources are provided for the double-effect absorption heat pump system and the single-effect absorption heat pump system respectively, completing the heating cycle; Determining that the current ambient temperature is greater than or equal to the first temperature threshold, controlling the cascade waste heat utilization system to switch to a cooling operation state, so that the cooling water input from the cooling return water end flows into the double-effect absorption heat pump system and the single-effect absorption heat pump system in two ways respectively; Gradiently utilizing auxiliary steam to provide a high-temperature heat source for the double-effect absorption heat pump system and the single-effect absorption heat pump system, so that the double-effect absorption heat pump system and the single-effect absorption heat pump system absorb heat from the cooling water; The cold end is used to aggregate the two cold water supply outputs of the double-effect absorption heat pump system and the single-effect absorption heat pump system; The low-temperature waste heat management system is used to dissipate the waste heat generated by auxiliary equipment, the double-effect absorption heat pump system and the single-effect absorption heat pump system to complete the cooling cycle.

2. The method according to claim 1, characterized in that The combined cooling and heating system further comprises a first circulation pump, and the cascade waste heat utilization system comprises a first stop valve, a second stop valve, a third stop valve, a fourth stop valve and a first three-way valve. One end of the first stop valve is connected to the heating return water end, and the other end of the first stop valve is connected to the first end of the first three-way valve through the circulating water pipeline via the double-effect absorption heat pump system, and is connected to the first end of the first three-way valve through the circulating water pipeline via the single-effect absorption heat pump system, and is connected to the first end of the first three-way valve through the circulating water pipeline via the second stop valve and the first heat exchanger. The second end of the first three-way valve is connected to the hot end, one end of the third stop valve is connected to the cold return water, and the other end of the third stop valve is connected to one end of the fourth stop valve through the circulating water pipeline via the single-effect absorption heat pump system, and the other end of the fourth stop valve is connected to the cold end. Wherein, during the heating cycle, the method further comprises: Respectively control the first stop valve and the second stop valve to open and the third stop valve and the fourth stop valve to close; Controlling the first end of the first three-way valve to be connected with the second end of the first three-way valve; Controlling hot water to be input into the first circulation pump through the first stop valve, so that under the action of the first circulation pump, the hot water is divided into three paths and respectively input into the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger; The auxiliary steam flowing in from the steam input end is subjected to a first-stage heat absorption treatment by hot water flowing into the double-effect absorption heat pump system, and the auxiliary steam after the first-stage heat absorption treatment is input into the single-effect absorption heat pump system; The auxiliary steam flowing in from the steam input end is subjected to a second-stage heat absorption treatment by hot water flowing into the single-effect absorption heat pump system, and the auxiliary steam after the second-stage heat absorption treatment is input into the first heat exchanger; The auxiliary steam input from the single-effect absorption heat pump system is subjected to a third-stage heat absorption treatment by using the first heat exchanger, and the auxiliary steam after the second-stage heat absorption treatment is output to the steam output end; The heated water outputted by the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger after absorbing heat is collected and connected to the hot end through the first end of the first three-way valve and the second end of the first three-way valve.

3. The method according to claim 2, characterized in that The cascade waste heat utilization system further includes a second three-way valve, a third three-way valve, a fourth three-way valve and a fifth three-way valve. The other end of the third stop valve is connected to the third end of the second three-way valve through a circulating water pipeline via a single-effect absorption heat pump system, the first end of the second three-way valve is connected to the first end of the third three-way valve, and the second end of the second three-way valve is connected to the third end of the fourth three-way valve through a circulating water pipeline via a double-effect absorption heat pump system; The other end of the third stop valve is also connected to the first end of the fourth three-way valve, and the second end of the fourth three-way valve is also connected to the third end of the fifth three-way valve; The other end of the first stop valve is also connected to the first end of the fifth three-way valve, the second end of the fifth three-way valve is connected to the second end of the third three-way valve through the circulating water pipeline and the low-temperature waste heat management system, and the third end of the third three-way valve is connected to the third end of the first three-way valve. Wherein, during the heating cycle, the method further comprises: Respectively control the second end of the second three-way valve to be connected with the first end of the second three-way valve, the first end of the third three-way valve to be connected with the second end of the third three-way valve, the second end of the fifth three-way valve to be connected with the third end of the fifth three-way valve, the first end of the fourth three-way valve to be connected with the second end of the fourth three-way valve, the first end of the fourth three-way valve to be connected with the third end of the fourth three-way valve, and the third end of the second three-way valve to be connected with the first end of the second three-way valve; A first waste heat utilization loop is formed between the double-effect absorption heat pump system, the fourth three-way valve, the fifth three-way valve, the low-temperature waste heat management system, the third three-way valve and the second three-way valve; A second waste heat utilization loop is provided between the single-effect absorption heat pump system, the fourth three-way valve, the fifth three-way valve, the low-temperature waste heat management system, the third three-way valve and the second three-way valve; A low-temperature heat source is provided to the double-effect absorption heat pump system and the single-effect absorption heat pump system through the first waste heat utilization loop and the second waste heat utilization loop.

4. The method according to claim 3, characterized in that: The waste heat management system includes an auxiliary equipment heat exchanger, a cold source heat exchanger and a second circulation pump. Wherein, during the heating cycle, the method further comprises: absorbing heat from the nuclear power production auxiliary equipment through the auxiliary heat exchanger to transfer the production waste heat corresponding to the nuclear power production auxiliary equipment to the circulating water in the waste heat management system; The circulating water outputted from the auxiliary heat exchanger flows into the fourth three-way valve through the fifth three-way valve respectively, and is divided into two paths of circulating water through the fourth three-way valve, wherein one path of circulating water releases heat through the evaporator in the double-effect absorption heat pump system to provide a low-temperature heat source for the double-effect absorption heat pump system, and the other path of circulating water releases heat through the evaporator of the single-effect absorption heat pump system to provide a low-temperature heat source for the single-effect absorption heat pump system; The two circulating water outputted by the evaporator in the double-effect absorption heat pump system and the evaporator in the single-effect absorption heat pump system are received and merged through the second three-way valve, and input into the cold source heat exchanger for heat release through the third three-way valve, so as to discharge the unused excess heat in the circulating water through the cold source heat exchanger; The circulating water output from the cold source heat exchanger is connected to the auxiliary equipment heat exchanger again in the form of circulating return water through the second circulating pump to complete the energy supply process of the low-temperature waste heat management system to the double-effect absorption heat pump system and the single-effect absorption heat pump system.

5. The method according to claim 3, characterized in that: The cascade waste heat utilization system also includes a third circulation pump, The execution of the cooling cycle also includes: Respectively control the third stop valve and the fourth stop valve to open, and the first stop valve to close; Respectively connecting the second end of the second three-way valve and the third end of the second three-way valve and connecting the first end of the fourth three-way valve and the third end of the fourth three-way valve; Controlling the cooling water input from the cooling water return end to be input into the third stop valve via the third circulation pump; Divide the cooling water supply into two routes, and respectively deliver one route of cooling water to the evaporator in the double-effect absorption heat pump system through the fourth three-way valve for heat release, and deliver the other route of cooling water directly to the evaporator in the single-effect absorption heat pump system for heat release; The cooling water outputted from the evaporator in the double-effect absorption heat pump system is outputted to the cold end through the fourth throttle valve via the second three-way valve; The cooling water outputted from the evaporator in the single-effect absorption heat pump system is outputted to the cold end through the fourth throttle valve.

6. The method according to claim 3, characterized in that Executing a cooling cycle also includes: Respectively connect the first end of the fifth three-way valve and the second end of the fifth three-way valve, connect the second end of the fifth three-way valve and the third end of the fifth three-way valve, connect the first end and the third end of the first three-way valve, connect the third end of the third three-way valve and the second end of the third three-way valve; A first heat release loop is formed between the low-temperature waste heat management system, the fifth three-way valve, the double-effect absorption heat pump system, the first three-way valve and the third three-way valve; A second heat release loop is formed between the low-temperature waste heat management system, the fifth three-way valve, the single-effect absorption heat pump system, the first three-way valve and the third three-way valve; The first heat release loop and the second heat release loop are used to dissipate waste heat generated by auxiliary equipment, a double-effect absorption heat pump system and a single-effect absorption heat pump system.

7. The method according to claim 6, characterized in that The waste heat management system includes an auxiliary equipment heat exchanger, a cold source heat exchanger and a third circulation pump. Wherein, in the cooling cycle, the first heat release loop and the second heat release loop are used to dissipate waste heat generated by auxiliary equipment, double-effect absorption heat pump system and single-effect absorption heat pump system, including: absorbing heat from the nuclear power production auxiliary equipment through the auxiliary equipment heat exchanger to transfer the production waste heat corresponding to the nuclear power production auxiliary equipment to the circulating water in the waste heat management system; Inputting the circulating water outputted from the auxiliary equipment heat exchanger into a fifth three-way valve; The circulating water input into the fifth three-way valve is divided into two paths through the fifth three-way valve, one of which absorbs heat through the absorber and condenser in the double-effect absorption heat pump system in turn, and the other circulating water absorbs heat through the absorber and condenser in the single-effect absorption heat pump system; The two-way circulating water outputted by the double-effect absorption heat pump system and the single-effect absorption heat pump system are received and merged through the first three-way valve, and input into the cold source heat exchanger for heat release through the first three-way valve and the third three-way valve, so as to discharge the heat carried in the circulating water through the cold source heat exchanger; The circulating water output from the cold source heat exchanger is connected to the auxiliary equipment heat exchanger again in the form of circulating return water through the second circulating pump.

8. The method according to claim 3, characterized in that The double-effect absorption heat pump system comprises a first high-pressure generator, a first solution heat exchanger, a first absorber, a low-pressure generator, a first condenser, a first evaporator, a first throttle valve, a second throttle valve, a third throttle valve, a fourth throttle valve, a first solution pump and a second solution pump. The first high-pressure generator is connected to the auxiliary steam provided by the nuclear power plant equipment through a steam pipeline. The first high-pressure generator is connected to the first absorber through a solution pipeline in sequence through a first solution pump, a first solution heat exchanger and a second solution pump. The first high-pressure generator is also connected to the first absorber through a solution pipeline in sequence through a first throttle valve, a first solution heat exchanger and a second throttle valve. The first high-pressure generator, the low-pressure generator, the third throttle valve and the first condenser are connected in sequence through a solution pipeline. The low-pressure generator is connected to the solution pipeline between the first solution heat exchanger and the first solution pump. The low-pressure generator is also connected to the solution pipeline between the first throttle valve and the first solution heat exchanger. The first condenser is connected to the first evaporator through a solution pipeline through a fourth throttle valve. The first evaporator and the first absorber are connected through a steam pipeline. Among them, the double-effect absorption heat pump system absorbs auxiliary steam heat in the following ways: Using the refrigerant solution in the first high-pressure generator to absorb the heat of the auxiliary steam to generate high-pressure refrigerator steam and concentrated refrigerant solution, respectively transporting the high-pressure refrigerator steam to the low-pressure generator and transporting the auxiliary steam after heat release to the single-effect absorption heat pump system; The high-pressure refrigerator steam is sequentially passed through the low-pressure generator, the third throttle valve, the first condenser, and the fourth throttle valve to release heat to the circulating water flowing into the double-effect absorption heat pump system, thereby obtaining liquid refrigerant and inputting it into the first evaporator; The liquid refrigerant is evaporated by absorbing heat using the low-temperature heat source provided by the low-temperature waste heat management system and the first evaporator, generating a gaseous refrigerant that flows into the first absorber; The absorbent in the first absorber absorbs the gaseous refrigerant to obtain a dilute refrigerant solution, and the heat generated in the absorption process is released to the circulating water flowing into the double-effect absorption heat pump system; The dilute refrigerant solution is pressurized by the second solution pump and then fed into the first solution heat exchanger. After the dilute refrigerant solution is initially heat-absorbed by the first solution heat exchanger, a portion of the dilute refrigerant solution is fed into the low-pressure generator, and the other portion of the dilute refrigerant solution is pressurized by the first solution pump and then fed into the first high-pressure generator. The concentrated refrigerant solution obtained after the first high-pressure generator is reduced in pressure by the first throttle valve and mixed with the concentrated refrigerant solution flowing out of the low-pressure generator, releases heat through the first solution heat exchanger, and is reduced in pressure again by the second throttle valve and then input into the first absorber.

9. The method according to claim 3, characterized in that: The single-effect absorption heat pump system comprises a second high-pressure generator, a second solution heat exchanger, a second absorber, a second condenser, a second evaporator, a fifth throttle valve, a sixth throttle valve and a third solution pump. The second high-pressure generator is connected to the auxiliary steam after heat release by the double-effect absorption heat pump system through a steam pipeline. The second high-pressure generator is connected to the second absorber through a solution pipeline in sequence through a second solution heat exchanger and a third solution pump. The second high-pressure generator is also connected to the second absorber through a solution pipeline in sequence through a second solution heat exchanger and a fifth throttle valve. The second high-pressure generator is connected to the second condenser through a solution pipeline. The second condenser is connected to the second evaporator through a solution pipeline through a sixth throttle valve. The second evaporator is connected to the second absorber through a steam pipeline. The hot water supply is connected to the circulating water pipeline of the second absorber through a first stop valve and a first circulating pump. The solution pipeline in the second absorber is also connected to the first end of the first three-way valve through the second condenser. Among them, the single-effect absorption heat pump system absorbs auxiliary steam heat in the following ways: utilizing the refrigerant solution in the second high-pressure generator to absorb the auxiliary steam heat transferred by the double-effect absorption heat pump system to generate high-pressure refrigerator steam and concentrated refrigerant solution; conveying high pressure refrigerator vapor to a second condenser; After the high-pressure refrigerator steam releases heat through the second condenser, liquid refrigerant is obtained and input into the second evaporator; The liquid refrigerant is evaporated by absorbing heat using the low-temperature heat source provided by the low-temperature waste heat management system and the second evaporator, generating a gaseous refrigerant that flows into the second absorber; The absorbent in the second absorber absorbs the gaseous refrigerant to obtain a dilute refrigerant solution, and the heat generated in the absorption process is released to the circulating water flowing into the single-effect absorption heat pump system; The dilute refrigerant solution is pressurized and input into the second solution heat exchanger by a third solution pump; The dilute refrigerant solution is transported to the second high-pressure generator after absorbing heat from the dilute refrigerant solution by the second solution heat exchanger; The concentrated refrigerant solution obtained after the second high-pressure generator is successively fed into the second absorber after releasing heat through the second solution heat exchanger and reducing pressure through the fifth throttle valve.

10. A nuclear power plant heat source management system, characterized in that: The nuclear power plant heat source management system includes a combined cooling and heating system and a low-temperature waste heat management system. The combined cooling and heating system includes a double-effect absorption heat pump system, a single-effect absorption heat pump system, a first heat exchanger and a cascade waste heat utilization system. The auxiliary steam is connected to the steam output end through a steam pipeline via the double-effect absorption heat pump system, the single-effect absorption heat pump system and the first heat exchanger. The nuclear power plant heat source management system also includes a processor, and the processor is applied to the thermal management method based on nuclear power plant equipment as described in any one of claims 1 to 9 above.

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