Molten salt steam extraction and energy storage thermodynamic system integrated with steam ejector

Abstract

The utility model provides a fused salt steam extraction and energy storage thermodynamic system integrated with a steam ejector, which relates to the technical field of thermal power generation and is characterized in that a first part of steam and a second part of steam are generated by a boiler of a thermal power generation system, and the thermal power generation system is connected with a fused salt energy storage system; and the hot water circulating system is used for converting the first part of steam into heat energy for storage, and then the hot water circulating system is connected with the thermal power generation system and the molten salt energy storage system to conduct water supply heat exchange between the second part of steam and the molten salt energy storage system. By the aid of the speed-increasing steam ejector, the steam extraction capacity of the fused salt energy storage system to the thermal power generation system is further improved while the feed water temperature is increased, the decoupling capacity of the boiler is improved, the lowest power generation output of the straight condensing unit is reduced on the basis that the lowest stable combustion load of the boiler is not reduced, and the efficiency of the unit is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of thermal power generation, in particular to a thermal system of molten salt steam extraction energy storage with an integrated steam ejector. Background Art

[0002] Thermal power generation refers to a method of generating electricity by converting the heat energy generated by the combustion of combustible materials into electricity through a power generation device. To ensure the stable power transmission capacity of new energy bases, it is required to reduce the minimum power output of thermal power generation units. Using conventional flexibility modification methods, it is difficult to further reduce the minimum power output of pure condensing units. Extraction steam storage technology extracts the main steam at the turbine inlet for heat and energy storage, which can reduce the amount of main steam entering the turbine for power generation, thereby achieving "partial decoupling of the turbine and boiler" for a certain period of time. Without reducing the minimum stable combustion load of the boiler, the minimum power output of the pure condensing unit can theoretically be significantly reduced.

[0003] The boiler feedwater of a conventional coal-fired power unit is heated through a superheater and reheater to form main steam, which then drives the turbine to generate electricity. The exhaust steam is cooled in a condenser to form water, which then continues to circulate in the thermal system of the molten salt steam extraction energy storage system in the integrated steam ejector of the thermal power plant. Low-temperature heaters are also installed in the energy storage units to drive their generation.

[0004] However, the existing technology has poor steam extraction capacity for thermal power units and cannot meet the peak regulation requirements of thermal power units. Utility Model Content

[0005] The utility model provides a molten salt steam extraction energy storage thermal system with an integrated steam ejector, which is used to solve the problem that the energy storage unit has poor steam extraction capacity for the thermal power unit and cannot meet the peak regulation requirement of the thermal power unit.

[0006] In a first aspect, an embodiment of the present invention provides a molten salt steam extraction energy storage thermal system with an integrated steam ejector, comprising:

[0007] A thermal power generation system includes a boiler for generating main steam, wherein the main steam includes a first portion of steam and a second portion of steam;

[0008] a molten salt energy storage system, connected to the thermal power generation system, for converting the first portion of steam into thermal energy for storage;

[0009] The hot water circulation system is connected to the thermal power generation system and the molten salt energy storage system respectively, and is used for exchanging heat between the second part of steam and the feed water of the molten salt energy storage system.

[0010] In one possible embodiment, the hot water circulation system includes a steam ejector and a hot water system;

[0011] The steam ejector is connected to the thermal power generation system and the hot water system respectively, and is used to eject the second part of the steam to obtain hot water, and then flow the hot water into the hot water system;

[0012] The hot water system is also connected to the molten salt energy storage system for heat exchange with the feed water of the molten salt energy storage system.

[0013] In a possible implementation, the hot water circulation system further includes a temperature and pressure reducing device;

[0014] The temperature and pressure reducing device is connected to the steam ejector and the hot water system respectively, and is used to reduce the temperature and / or pressure of the hot water flowing from the steam ejector to the hot water system.

[0015] In a possible implementation, the hot water circulation system further includes a temperature and pressure detection module;

[0016] The temperature and pressure detection modules are connected to the temperature and pressure reducing device and the hot water system respectively, and are used to detect the temperature and / or pressure of the hot water flowing out of the temperature and pressure reducing device.

[0017] In a possible embodiment, the thermal power generation system further includes a first generator set, and the main steam further includes a third portion of steam;

[0018] The first generator set is connected to the boiler and is used for converting the third portion of steam into electrical energy.

[0019] In a possible implementation, the thermal power generation system further includes a first condensing unit and a feed water pump;

[0020] The boiler, the first generator set, the first condensing unit and the feedwater pump are connected in sequence;

[0021] The first condensing unit is used to cool the exhaust steam flowing out of the first generator unit to obtain circulating water;

[0022] Feedwater pumps are used to deliver circulating water to the boiler.

[0023] In a possible implementation, the first generator set includes a first steam turbine and a first generator.

[0024] In one possible embodiment, the molten salt energy storage system includes a molten salt heat exchange module, a molten salt power generation module and a molten salt energy storage module;

[0025] The molten salt heat exchange module is connected to the molten salt energy storage module, and the molten salt energy storage module is connected to the molten salt power generation module;

[0026] The molten salt heat exchange module and the molten salt energy storage module are used to convert the first part of steam into thermal energy for storage;

[0027] The molten salt power generation module is used to convert stored thermal energy into electrical energy.

[0028] In one possible embodiment, the molten salt heat exchange module includes a molten salt heat exchanger, and the molten salt energy storage module includes a molten salt cold tank and a molten salt hot tank;

[0029] The first end of the molten salt heat exchanger is connected to the thermal power generation system, the second end of the molten salt heat exchanger is connected to the molten salt hot tank, and the third end of the molten salt heat exchanger is connected to the molten salt cold tank.

[0030] In one possible embodiment, the molten salt power generation module includes a first steam generator, a second steam generator, and a second generator set;

[0031] The first steam generator is connected to the molten salt hot tank, the second steam generator and the second generator set respectively;

[0032] The second steam generator is also connected to the molten salt cooling tank.

[0033] The first and second steam are generated by the thermal power generation system's boiler. The thermal power generation system is then connected to a molten salt energy storage system to convert the first steam into thermal energy for storage. The hot water circulation system is then connected to both the thermal power generation system and the molten salt energy storage system, respectively, to exchange heat between the second steam and the molten salt energy storage system's feedwater. The hot water circulation system, through steam ejectors, not only raises the feedwater temperature but also further improves the molten salt energy storage system's steam extraction capacity for the thermal power generation system, thereby enhancing boiler-turbine decoupling capabilities. By integrating steam ejectors, molten salt heat storage, and a thermal system into a low-load, high-efficiency configuration, the problem of a significant drop in feedwater temperature under low loads is addressed. This reduces the minimum power generation output of the condensing unit without reducing the boiler's minimum stable combustion load, thereby improving unit efficiency.

[0034] The structure of the present invention and its other purposes and beneficial effects will be more clearly understood through the description of the preferred embodiments in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0036] Figure 1 A schematic diagram of the structure of a thermal system for molten salt steam extraction energy storage with an integrated steam ejector provided in an embodiment of the present invention;

[0037] Figure 2 A schematic structural diagram of a thermal power generation system provided by an embodiment of the present utility model;

[0038] Figure 3 A schematic structural diagram of a molten salt energy storage system provided in an embodiment of the present utility model;

[0039] Figure 4 This is a structural schematic diagram of a hot water circulation system provided in an embodiment of the present utility model.

[0040] Description of reference numerals:

[0041] 10-thermal power generation system; 11-boiler; 12-first generator set; 13-first condensing unit; 14-feedwater pump;

[0042] 121-first steam turbine; 122-first generator;

[0043] 131-first condenser; 132-first condensing tower;

[0044] 20-molten salt energy storage system; 21-molten salt heat exchange module; 22-molten salt power generation module; 23-molten salt energy storage module;

[0045] 211-molten salt heat exchanger; 212-molten salt electric heater; 213-cold salt pump;

[0046] 221-first steam generator; 222-second steam generator; 223-second generator set;

[0047] 231-molten salt cold tank; 232-molten salt hot tank;

[0048] 30-hot water circulation system; 31-steam ejector; 32-hot water system; 33-temperature and pressure reducing device; 34-temperature and pressure detection module; 35-feed water pump of the second generator set; 36-high-temperature heater; 37-condensing turbine of the second generator set; 38-condensing tower of the second generator set; 39-shaft seal heater. DETAILED DESCRIPTION

[0049] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0050] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0051] In the description of the present invention, it should be understood that the terms "including" and "having" and any variations thereof used herein are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0052] Unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integration; they can refer to direct connections or indirect connections through an intermediary; they can refer to internal connections between two components or interactions between two components. Those skilled in the art will understand the specific meanings of these terms in this utility model based on the specific circumstances. Furthermore, the terms "first," "second," etc., etc., are used for descriptive purposes only and should not be construed to indicate or imply relative importance or implicitly specify the quantity of the technical features indicated.

[0053] In the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0054] Thermal power generation utilizes the heat generated by the combustion of combustibles and converts it into electricity through a generator. To ensure stable power transmission from new energy bases, the minimum output of thermal power units must be reduced.

[0055] During the operation of coal-fired power units, the boiler output and turbine output (including heat supply) generally maintain a real-time balance. Therefore, due to the limitation of the boiler's minimum stable combustion load, it is difficult to further reduce the minimum power generation output of pure condensing units by adopting conventional flexibility transformation methods.

[0056] At the same time, the boiler heating feed water of traditional coal-fired power units is heated into main steam through the superheater and reheater, which drives the steam turbine to generate electricity. The exhausted steam flowing out is cooled into water through the condenser and continues to participate in the circulation of the thermal power system. A low-temperature heater is also configured for the energy storage unit to drive the energy storage unit to generate electricity. The overall consumption is difficult to reduce.

[0057] To address the above-mentioned issues, the inventors discovered that extraction steam storage technology, which extracts main steam from the turbine inlet for thermal storage and energy storage, can reduce the amount of main steam entering the turbine for power generation, thereby achieving "partial decoupling of the turbine and boiler" for a certain period of time. This can theoretically significantly reduce the minimum power generation output of a pure condensing unit without reducing the boiler's minimum stable combustion load. Furthermore, the low-temperature heater traditionally used in small turbines is eliminated and replaced by a hot water system. The ejected hot water enters the hot water system, where it mixes with the hot water flowing out of the molten salt heat exchanger. The mixed hot water from the hot water system then enters the molten salt heat exchange system for heat exchange and work. Extraction steam storage utilizes steam from the turbine inlet for energy storage, reducing the amount of steam used for power generation, thereby achieving "partial decoupling of the turbine and boiler" for a certain period of time. This further reduces the minimum power generation output of a pure condensing unit without reducing the boiler's minimum stable combustion load. Based on this, the present invention proposes a molten salt extraction steam storage thermal system with an integrated steam ejector to reduce the minimum power generation output of a pure condensing unit without reducing the boiler's minimum stable combustion load.

[0058] The following specific embodiments describe in detail the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0059] Figure 1 The schematic diagram of the structure of the thermal system of molten salt steam extraction energy storage with integrated steam ejector provided by the embodiment of the present invention is as follows: Figure 1 As shown, the thermal system of molten salt steam extraction energy storage with integrated steam ejector provided in the embodiment of the present invention includes: a thermal power generation system 10, a molten salt energy storage system 20 and a hot water circulation system 30.

[0060] The thermal power generation system 10 includes a boiler 11 for generating main steam, and the main steam includes a first portion of steam and a second portion of steam.

[0061] Specifically, the first portion of steam and the second portion of steam account for 20% to 30% of the main steam.

[0062] The molten salt energy storage system 20 is connected to the thermal power generation system 10 and is used to convert the first part of steam into thermal energy for storage.

[0063] Specifically, the boiler 11 is heated, and the feed water is heated through the superheater and the reheater to generate main steam. The main steam is high-temperature steam. The first steam enters the molten salt energy storage system 20 and is converted into thermal energy for storage.

[0064] The hot water circulation system 30 is connected to the thermal power generation system 10 and the molten salt energy storage system 20 respectively, and is used to exchange heat between the second part of steam and the feed water of the molten salt energy storage system 20 .

[0065] In an embodiment of the present invention, a first portion of steam and a second portion of steam are generated by the boiler of a thermal power generation system, and the thermal power generation system is connected to a molten salt energy storage system to convert the first portion of steam into thermal energy for storage. The hot water circulation system is then connected to the thermal power generation system and the molten salt energy storage system respectively to perform heat exchange between the second portion of steam and the feed water of the molten salt energy storage system. The hot water circulation system uses a steam ejector to increase the feed water temperature while further improving the steam extraction capacity of the molten salt energy storage system for the thermal power generation system, thereby improving the decoupling capacity of the machine and boiler. By establishing a low-load and high-efficiency configuration integrating a steam ejector, molten salt heat storage and a thermal system, the problem of a significant drop in feed water temperature under low load is solved. This achieves the goal of reducing the minimum power generation output of the pure condensing unit without reducing the minimum stable combustion load of the boiler, thereby improving the unit efficiency.

[0066] The present invention also provides a preferred embodiment. Figure 2 The structural diagram of the thermal power generation system provided by the embodiment of the utility model is as follows: Figure 3 As shown, the thermal power generation system 10 provided in the embodiment of the present invention further includes: a first generator set 12 , a first condensing unit 13 and a feed water pump 14 .

[0067] Among them, the main steam also includes a third part of steam.

[0068] Specifically, the third part steam accounts for 80% to 70% of the main steam.

[0069] The first generator set 12 includes a first steam turbine 121 and a first generator 122 .

[0070] The first generator set 12 is connected to the boiler 11 and is used to convert the third portion of steam into electrical energy.

[0071] Specifically, the third part of the steam flows to the first generator set 12, and the steam drives the first generator 122 to generate electricity, thereby converting the third part of the steam into electrical energy to ensure that the first steam turbine 121 achieves 15-20% load power generation.

[0072] The boiler 11, the first generator set 12, the first condensing unit 13 and the feed water pump 14 are connected in sequence.

[0073] The first condensing unit 13 is used to cool the exhaust steam from the first generator set 12 to produce circulating water. The feed water pump 14 is used to deliver the circulating water to the boiler 11.

[0074] More specifically, after the third portion of steam starts the first steam turbine 121 , exhaust steam will flow out. The exhaust steam is cooled into water by the first condensing unit 13 and then sent to the boiler 11 through the feed water pump 14 .

[0075] It should be noted that the first condensing unit 13 includes a first condenser 131 and a first condensing tower 132 .

[0076] In the embodiment of the present invention, the unused steam is re-cooled and condensed by the first condensing unit 13 and the feed water pump 14 and sent back to the boiler 11, thereby realizing water circulation and saving costs.

[0077] The present invention also provides a preferred embodiment, which provides an operation process of a thermal power generation system 10 of a thermal system with molten salt steam extraction energy storage and an integrated steam ejector provided in an embodiment of the present invention.

[0078] like Figure 2 As shown, the steam generated by heating in the boiler 11, the third part of the steam passes through the first steam turbine 121 and the first generator 122, a part of the steam drives the first generator 122 to generate electricity, converting the third part of the steam into electrical energy, and the electrical energy drives the first steam turbine 121 to start operation; the other part of the steam flows out of the first steam turbine 121, passes through the first condenser 131 and the first condensing tower 132, and is condensed into liquid water. The water flows along the pipeline into the water pump 14, and the water pump 14 sends the water back to the boiler 11.

[0079] In the embodiment of the present invention, the unused steam is re-cooled and condensed by the first condensing unit 13 and the feed water pump 14 and sent back to the boiler 11, thereby realizing water circulation and saving costs.

[0080] The present invention also provides a preferred embodiment. Figure 4 The schematic diagram of the structure of the molten salt energy storage system provided by the embodiment of the present invention is as follows: Figure 4 As shown, the molten salt energy storage system 20 provided in the embodiment of the present invention includes: a molten salt heat exchange module 21, a molten salt power generation module 22 and a molten salt energy storage module 23.

[0081] The molten salt heat exchange module 21 is connected to the molten salt energy storage module 23 , and the molten salt energy storage module 23 is connected to the molten salt power generation module 22 .

[0082] Specifically, the molten salt heat exchange module 21 includes a molten salt heat exchanger 211 , and the molten salt energy storage module 23 includes a molten salt cold tank 231 and a molten salt hot tank 232 .

[0083] More specifically, a first end of the molten salt heat exchanger 211 is connected to the thermal power generation system 10 , a second end of the molten salt heat exchanger 21 is connected to the molten salt hot tank 232 , and a third end of the molten salt heat exchanger 21 is connected to the molten salt cold tank 231 .

[0084] The molten salt heat exchange module 21 and the molten salt energy storage module 23 are used to convert the first portion of steam into thermal energy for storage.

[0085] Specifically, the first portion of steam exchanges heat with the molten salt in the molten salt heat exchanger 211 and flows out of the molten salt into the molten salt hot tank 232 .

[0086] It should be noted that the molten salt heat exchange module 21 further includes a molten salt electric heater 212 .

[0087] Specifically, molten salt electric heater 212 is connected in series to the port pipe at the second end of molten salt heat exchanger 211. When molten salt energy storage system 20 starts circulating, it heats the molten salt from a cold state to a hot, flowing state. If the heat exchange capacity of molten salt electric heater 212 is insufficient, abandoned electricity from new energy sources can be used to heat the molten salt, ensuring the normal operation of the molten salt energy storage system.

[0088] The molten salt power generation module 22 includes a first steam generator 221 , a second steam generator 222 and a second generator set 223 .

[0089] Specifically, the first steam generator 221 is connected to the molten salt hot tank 232 , the second steam generator 222 and the second generator set 223 , respectively. The second steam generator 222 is also connected to the molten salt cold tank 231 .

[0090] The molten salt power generation module 22 is used to convert the stored thermal energy into electrical energy.

[0091] Specifically, the molten salt flows into the first steam generator 221 and the second steam generator 222 to be heated to remove the brine, and the generated steam drives the second generator set 223 to generate electricity, thereby generating electrical energy; the generated molten salt flows into the molten salt cold tank 231.

[0092] More specifically, the first steam generator 221 and the second steam generator 222 are used to remove brine from the molten salt. The second steam generator 222 is connected to the second generator set feed water pump, and the second generator set feed water pump pumps the brine away.

[0093] It should be noted that the molten salt heat exchange module 21 further includes a cold salt pump 213 .

[0094] After the molten salt flows into the molten salt cold tank 231 and is cooled, the low-temperature molten salt in the molten salt cold tank 231 is extracted by the cold salt pump 213 and sent back to the molten salt heat exchanger 211 through a pipeline for heating.

[0095] In the embodiment of the present invention, the molten salt heat exchange module 21, the molten salt power generation module 22, and the molten salt energy storage module 23 realize heat exchange between steam and molten salt, converting heat energy into electrical energy to generate electricity for the second generator set 223. At the same time, the molten salt is sent to the molten salt heat exchanger 211 through the cold salt pump 213 for circulation and heating, realizing energy conversion and storage, and saving costs.

[0096] The present invention also provides a preferred embodiment, which provides an operation process of the molten salt energy storage system 20 of the thermal system of the molten salt steam extraction energy storage with an integrated steam ejector provided in the embodiment of the present invention.

[0097] like Figure 3 As shown, the first part of the steam generated by heating by the boiler 11 enters the molten salt heat exchanger 211 for heat exchange and flows out of the molten salt. The molten salt passes through the molten salt hot tank 232 and enters the first steam generator 221 and the second steam generator 222 for heating to remove the brine. The generated steam drives the second generator set 223 to convert the steam into electrical energy; the remaining molten salt enters the molten salt cold tank 231 for low-temperature cooling, and the cold salt pump 213 extracts the low-temperature molten salt and sends it into the molten salt heat exchanger 211.

[0098] In the embodiment of the present invention, the molten salt heat exchange module 21, the molten salt power generation module 22, and the molten salt energy storage module 23 realize heat exchange between steam and molten salt, converting heat energy into electrical energy to generate electricity for the second generator set 223. At the same time, the molten salt is sent to the molten salt heat exchanger 211 through the cold salt pump 213 for circulation and heating, realizing energy conversion and storage, and saving costs.

[0099] The present invention also provides a preferred embodiment. Figure 4 A schematic diagram of the structure of the hot water circulation system provided by the embodiment of the present utility model is shown as follows: Figure 4 As shown, the hot water circulation system 30 provided in the embodiment of the present invention includes: a steam ejector 31, a hot water system 32, a temperature and pressure reducer 33, a temperature and pressure detection module 34, a second generator set feed water pump 35, a high-temperature heater 36, a second generator set condenser 37, a second generator set condensing tower 38 and a shaft seal heater 39.

[0100] The steam ejector 31 is connected to the thermal power generation system 10 and the hot water system 32 respectively, and is used to eject the second part of the steam to obtain hot water, and then flow the hot water into the hot water system 32 .

[0101] Specifically, the steam ejector 31 utilizes the second portion of steam to eject and condense to obtain hot water, and the hot water flows into the hot water system 32 .

[0102] Optionally, the steam ejector 31 can be supplied by the boiler 11, further enhancing the ability of the second molten salt generator set to increase steam utilization in the thermal power generation system 10. Furthermore, the steam ejector 31 consumes no electricity during normal operation, reducing the amount of desalinated water required to replenish the condenser, thereby achieving cost savings.

[0103] The hot water system 32 is also connected to the molten salt energy storage system 20 for heat exchange with the feed water of the molten salt energy storage system 20 .

[0104] Specifically, the water source of the hot water system 32 includes steam cooling water from the molten salt energy storage system 20 and feed water from the steam ejector 31 .

[0105] More specifically, the two water sources have different temperatures and pressures, so a temperature and pressure reducer 33 is provided in the pipeline, and a temperature and pressure detection module 34 is provided at the outlet.

[0106] The temperature and pressure reducing device 33 is connected to the steam ejector 31 and the hot water system 32 respectively, and is used to reduce the temperature and / or pressure of the hot water flowing from the steam ejector 31 to the hot water system 32.

[0107] Specifically, the temperature-reducing and pressure-reducing device 33 is connected to the steam ejector 31, and is used to process the hot water obtained when the second part of the steam enters the steam ejector 31; the temperature-reducing and pressure-reducing device 33 is connected to the hot water system 32, and is used to process the exhaust steam condensate converted from the steam after the first part of the steam enters the molten salt electric heater 212 for heat exchange.

[0108] The temperature and pressure detection module 34 is connected to the temperature and pressure reducing device 33 and the hot water system 32 respectively, and is used to detect the temperature and / or pressure of the hot water flowing out of the temperature and pressure reducing device 33 .

[0109] It should be noted that the water source of the hot water system 32 also includes the brine pumped from the molten salt energy storage system 20 by the second generator set water pump 35 .

[0110] Specifically, one end of the second generator set feedwater pump 35 is connected to the second steam generator 222 , and the other end is connected to the high-temperature heater 36 .

[0111] More specifically, the second generator set feedwater pump 35 extracts brine from the second steam generator 222 , passes the brine into the high-temperature heater 36 for heating, and then sends it into the hot water system 32 .

[0112] It should also be noted that the water source of the hot water system 32 also includes hot water obtained by condensing and heating the remaining steam from the second generator set 223 .

[0113] Specifically, the remaining steam from the second generator set 223 enters the second generator set condenser 37 into the second generator set condensation tower 38 to generate condensed water, which enters the shaft seal heater 39 to be heated to obtain hot water, and then is sent to the hot water system 32.

[0114] In addition, the hot water system 32 may use a high-temperature pressure tank as a water storage container and wrap it with insulation material to maintain stable parameters in the container.

[0115] In the embodiment of the present utility model, the low-temperature heater is eliminated on the basis of the traditional thermal system, and this part of the function is replaced by the hot water system 32, and the main steam is ejected by the steam ejector 31, thereby realizing direct heat exchange between steam and the feed water of the second generator set, improving the integration of the thermal system of the second generator set, solving the problem of a significant drop in feed water temperature under low load, and forming an energy efficiency improvement technology under large-scale peak regulation of the unit.

[0116] The present invention also provides a preferred embodiment, which provides an operation process of the hot water circulation system 30 of the thermal system of the molten salt steam extraction energy storage with an integrated steam ejector provided in the embodiment of the present invention.

[0117] like Figure 3 As shown, the second part of the steam generated by heating in the boiler 11 enters the steam ejector 31 for ejection and condensation, and the outflowing hot water passes through the temperature and pressure reducing device 33 and enters the hot water system 32.

[0118] Optionally, the first part of the steam generated by heating in the boiler 11 enters the molten salt heat exchanger 211 for heat exchange, and the remaining part of the steam enters the pipeline for cooling, and the generated condensed water enters the hot water system 32 through the temperature and pressure reducer 33.

[0119] Optionally, brine is pumped out of the second steam generator 222 by the second generator set feed water pump 35 , heated by the high-temperature heater 36 , and the generated hot water enters the hot water system 32 .

[0120] More optionally, the remaining steam from the second generator set 223 is condensed through the second generator set condenser 37 and the second generator set condensation tower 38, the generated condensed water is heated by the shaft seal heater 39, and the generated hot water enters the hot water system 32 through the steam ejector 31 and the temperature and pressure reducer 33.

[0121] Furthermore, the hot water system 32 heats the incoming water, and the generated hot water is discharged after being tested by the temperature and pressure detection module 34 .

[0122] In this embodiment, the low-temperature heater is eliminated from the traditional thermal system and replaced by a hot water system 32. A steam ejector 31 is used to inject main steam. A temperature and pressure detection module 34 monitors the outlet water temperature and pressure of the hot water system 32. The high-temperature and high-pressure hot water is then cooled and decompressed by a desuperheater 33, ensuring that the hot water entering the hot water system meets water supply requirements. This improves the feedwater temperature while also enhancing the integration of the second generator set 223, reducing thermal power output and improving turbine-boiler decoupling capabilities.

[0123] The serial numbers of the embodiments of this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. The above are only preferred embodiments of this application and do not limit the scope of the patent of this application. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the scope of patent protection of this application.

[0124] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A molten salt steam extraction energy storage thermal system with integrated steam ejector, characterized in that: include: A thermal power generation system includes a boiler for generating main steam, wherein the main steam includes a first portion of steam and a second portion of steam; a molten salt energy storage system, connected to the thermal power generation system, for converting the first portion of steam into thermal energy for storage; A hot water circulation system is connected to the thermal power generation system and the molten salt energy storage system respectively, and is used for exchanging heat between the second portion of steam and the feed water of the molten salt energy storage system.

2. The molten salt steam extraction energy storage thermal system with integrated steam ejector according to claim 1 is characterized in that: The hot water circulation system includes a steam ejector and a hot water system; The steam ejector is connected to the thermal power generation system and the hot water system respectively, and is used to eject the second portion of steam to obtain hot water, and then flow the hot water into the hot water system; The hot water system is also connected to the molten salt energy storage system for heat exchange with the feed water of the molten salt energy storage system.

3. The molten salt steam extraction energy storage thermal system with integrated steam ejector according to claim 2 is characterized in that: The hot water circulation system further includes a temperature and pressure reducing device; The temperature and pressure reducing device is connected to the steam ejector and the hot water system respectively, and is used to reduce the temperature and / or pressure of the hot water flowing from the steam ejector into the hot water system.

4. The molten salt steam extraction energy storage thermal system with integrated steam ejector according to claim 3 is characterized in that: The hot water circulation system also includes a temperature and pressure detection module; The temperature and pressure detection modules are connected to the temperature and pressure reducing device and the hot water system respectively, and are used to detect the temperature and / or pressure of the hot water flowing out of the temperature and pressure reducing device.

5. The molten salt steam extraction energy storage thermal system with integrated steam ejector according to any one of claims 1 to 4, characterized in that: The thermal power generation system further includes a first generator set, and the main steam further includes a third portion of steam; The first generator set is connected to the boiler and is used to convert the third portion of steam into electrical energy.

6. The molten salt steam extraction energy storage thermal system with integrated steam ejector according to claim 5 is characterized in that: The thermal power generation system further includes a first condensing unit and a feed water pump; The boiler, the first generator set, the first condensing unit and the feedwater pump are connected in sequence; The first condensing unit is used to cool the exhaust steam flowing out of the first generator unit to obtain circulating water; The feed water pump is used to deliver the circulating water to the boiler.

7. The molten salt steam extraction energy storage thermal system with integrated steam ejector according to claim 6 is characterized in that: The first generator set includes a first steam turbine and a first generator.

8. The molten salt steam extraction energy storage thermal system with integrated steam ejector according to any one of claims 1 to 4, characterized in that: The molten salt energy storage system includes a molten salt heat exchange module, a molten salt power generation module and a molten salt energy storage module; The molten salt heat exchange module is connected to the molten salt energy storage module, and the molten salt energy storage module is connected to the molten salt power generation module; The molten salt heat exchange module and the molten salt energy storage module are used to convert the first portion of steam into thermal energy for storage; The molten salt power generation module is used to convert the stored thermal energy into electrical energy.

9. The molten salt steam extraction energy storage thermal system with integrated steam ejector according to claim 8, characterized in that: The molten salt heat exchange module includes a molten salt heat exchanger, and the molten salt energy storage module includes a molten salt cold tank and a molten salt hot tank; The first end of the molten salt heat exchanger is connected to the thermal power generation system, the second end of the molten salt heat exchanger is connected to the molten salt hot tank, and the third end of the molten salt heat exchanger is connected to the molten salt cold tank.

10. The molten salt steam extraction energy storage thermal system with integrated steam ejector according to claim 9, characterized in that: The molten salt power generation module includes a first steam generator, a second steam generator and a second generator set; The first steam generator is connected to the molten salt hot tank, the second steam generator and the second generator set respectively; The second steam generator is also connected to the molten salt cold tank.

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