A pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system

Abstract

The invention discloses a pressurized water reactor nuclear power unit combined with a high-temperature molten salt energy storage and graded steam supply system, belonging to the technical field of nuclear power energy storage. The pressurized water reactor nuclear power unit combined with a high-temperature molten salt energy storage and graded steam supply system, when the nuclear power unit is in base load operation, all the main steam enters the main steam turbine generator set, and when the nuclear power unit is in peak load operation and load reduction operation, a part of the steam is supplied to low-temperature steam users, and the excess electricity is supplied to an electric heater from a plant transformer in the form of plant electricity, which is used to increase the molten salt temperature. When the user-side requires high steam parameters, the high-temperature molten salt heats the saturated steam of the pressurized water reactor nuclear power unit to the temperature level required by the user through heat exchangers of different temperature levels, and the nuclear power unit can adapt to the peak load demand of the power grid. During the peak load period, the utilization rate of nuclear fuel is improved through the molten salt energy storage method, and steam of different qualities can be provided to downstream users.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear power energy storage, and in particular to a pressurized water reactor nuclear power unit combined with a high-temperature molten salt energy storage graded steam supply system. Background Art

[0002] Most nuclear power plants currently adopt the base load mode and rarely participate in the rapid peak load regulation process of the power grid. With the transformation and upgrading of the national energy policy, the task demand of nuclear power plants to participate in peak load regulation has become increasingly important. The nuclear fuel in the core of a nuclear power plant is designed to meet the base load operation for one refueling cycle. When the nuclear fuel reaches the burnup depth, the core will be refueled. The refueling cycle is fixed. If the nuclear power plant participates in peak load regulation, the nuclear fuel will be replaced if the nuclear fuel does not reach the designed burnup during the refueling cycle. This is a waste of energy for the nuclear power plant, which reduces the economic efficiency and increases the difficulty of spent fuel reprocessing. With the increase in the demand for comprehensive utilization of nuclear energy, the demand for nuclear power plants to supply steam and heat for other users has further increased. Industrial steam supply usually requires steam with different levels of parameters above 400 degrees Celsius, but the steam supply parameters of pressurized water reactor nuclear power plants are relatively low, which limits the advantages of pressurized water reactor nuclear power plants in the comprehensive utilization of nuclear energy. Summary of the invention

[0003] In view of the problem that the above-mentioned existing technologies limit the advantages of pressurized water reactor nuclear power plants in the comprehensive utilization of nuclear energy, the present invention is proposed.

[0004] Therefore, the technical problem to be solved by the present invention is to limit the advantages of pressurized water reactor nuclear power plants in the comprehensive utilization of nuclear energy.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a pressurized water reactor nuclear power unit combined with a high-temperature molten salt energy storage staged steam supply system, comprising:

[0006] A steam generator, wherein the steam generator is provided with a main steam pipeline;

[0007] An electric heater, wherein the electric heater is arranged at one end of the steam generator, and a high-temperature molten salt storage tank is arranged at the other end of the electric heater;

[0008] A generator is arranged at one end of a main steam pipeline, and a main transformer is arranged at one end of the generator.

[0009] As a further solution of the present invention: the main steam pipeline is provided with a main steam regulating valve group, a bypass valve group and a steam supply valve group in parallel.

[0010] As a further solution of the present invention: a condenser is arranged at one end of the main steam regulating valve group, and a steam turbine group is arranged on the condenser.

[0011] As a further solution of the present invention: the steam turbine unit and the bypass valve unit are interconnected, and the steam turbine unit is connected to the main steam pipeline.

[0012] As a further solution of the present invention: a main transformer and a plant transformer are connected in parallel to the generator, and one end of the main transformer is connected in series to a power grid.

[0013] As a further solution of the present invention: an electric heater is provided at one end of the plant transformer, and a high-temperature molten salt storage tank and a low-temperature molten salt pump are connected in parallel to the electric heater.

[0014] As a further solution of the present invention: a high-temperature molten salt pump is provided at one end of the high-temperature molten salt storage tank, and a secondary heater is provided at one end of the high-temperature molten salt pump.

[0015] As a further solution of the present invention: a primary heater is arranged at one end of the secondary heater, and a low-temperature molten salt storage tank is arranged on the primary heater.

[0016] As a further solution of the present invention: the low-temperature molten salt storage tank is arranged at one end of the low-temperature molten salt pump.

[0017] As a further solution of the present invention: one end of the primary heater is provided with a high-temperature steam end, a medium-temperature steam end and a low-temperature steam end.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: the pressurized water reactor nuclear power unit is combined with a high-temperature molten salt energy storage and graded steam supply system. When the nuclear power unit is operating at base load, all the main steam enters the main steam turbine generator set. When the nuclear power unit is operating at peak load, part of the steam is supplied to low-temperature steam users, and the excess electricity is supplied to the electric heater from the plant transformer in the form of plant electricity to increase the molten salt temperature. When the user-side steam parameter demand is high, the high-temperature molten salt heats the saturated steam of the pressurized water reactor nuclear power unit to the temperature level required by the user through heat exchangers of different temperature levels. The nuclear power unit can adapt to the peak load demand of the power grid. During the peak load period, the utilization rate of nuclear fuel is improved through molten salt energy storage, and steam of different qualities can be provided to downstream users. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0020] Figure 1 A schematic diagram of the overall structure of a pressurized water reactor nuclear power unit combined with a high-temperature molten salt energy storage and graded steam supply system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0022] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0023] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0024] Furthermore, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or selective embodiment that is mutually exclusive with other embodiments.

[0025] Example 1

[0026] like Figure 1 As shown, the present invention provides a technical solution: a pressurized water reactor nuclear power unit combined with a high-temperature molten salt energy storage staged steam supply system, comprising:

[0027] A steam generator 100, wherein the steam generator 100 is provided with a main steam pipeline 101, an electric heater 200, wherein the electric heater 200 is provided at one end of the steam generator 100, and a high-temperature molten salt storage tank 201 is provided at the other end of the electric heater 200, and a generator 300, wherein the generator 300 is provided at one end of the main steam pipeline 101, and a main transformer 301 is provided at one end of the generator 300;

[0028] Preferably, the main steam pipe 101 is provided with a main steam regulating valve group 102, a bypass valve group 103 and a steam supply valve group 104 in parallel, a condenser 105 is provided at one end of the main steam regulating valve group 102, a steam turbine unit 106 is provided on the condenser 105, the steam turbine unit 106 and the bypass valve group 103 are interconnected, and the steam turbine unit 106 is connected to the main steam pipe 101.

[0029] In this embodiment, the main steam from the steam generator 100 outlet to the main steam pipeline 101 is divided into three routes. One route is to enter the steam turbine unit 106 for power generation through the main steam regulating valve group 102, the second route is to flow into the condenser 105 through the bypass valve group 103, and the third route is to supply three types of steam users through the steam supply valve group 104. At the same time, the steam that cannot be consumed by the steam users will also re-enter the condenser 105 through the pipeline, and re-enter the steam generator 100 after condensation for recycling.

[0030] Example 2

[0031] Combined with Figure 1 , it is obtained that: the steam generator 100 is provided with a main steam pipeline 101, the electric heater 200 is provided at one end of the steam generator 100, and a high-temperature molten salt storage tank 201 is provided at the other end of the electric heater 200, and the generator 300 is provided at one end of the main steam pipeline 101, and a main transformer 301 is provided at one end of the generator 300;

[0032] Preferably, the generator 300 is connected in parallel with a main transformer 301 and a plant transformer 303, one end of the main transformer 301 is connected in series with a power grid 302, one end of the plant transformer 303 is provided with an electric heater 200, and the electric heater 200 is connected in parallel with a high-temperature molten salt storage tank 201 and a low-temperature molten salt pump 206.

[0033] In this embodiment: during the period of reduced load operation of the unit, part of the electricity generated by the generator 300 is sent to the power grid 302 through the main transformer 301 to meet the power grid demand, and the excess electricity is supplied to the electric heater 200 through the plant transformer 303. The electric heater 200 is used to heat the low-temperature molten salt. The electric heater 200, the high-temperature molten salt storage tank 201, the high-temperature molten salt pump 202, the secondary heater 203, the primary heater 204, the low-temperature molten salt storage tank 205, and the low-temperature molten salt pump 206 form a closed molten salt circuit, wherein the molten salt in the high-temperature molten salt storage tank 201 is 700℃-750℃, and the molten salt in the low-temperature molten salt storage tank 205 is 300℃-350℃.

[0034] Example 3

[0035] Combined with Figure 1 , it is obtained that: the steam generator 100 is provided with a main steam pipeline 101, the electric heater 200 is provided at one end of the steam generator 100, and a high-temperature molten salt storage tank 201 is provided at the other end of the electric heater 200, and the generator 300 is provided at one end of the main steam pipeline 101, and a main transformer 301 is provided at one end of the generator 300;

[0036] Preferably, a high-temperature molten salt pump 202 is provided at one end of the high-temperature molten salt storage tank 201, a secondary heater 203 is provided at one end of the high-temperature molten salt pump 202, a primary heater 204 is provided at one end of the secondary heater 203, a low-temperature molten salt storage tank 205 is provided on the primary heater 204, the low-temperature molten salt storage tank 205 is provided at one end of the low-temperature molten salt pump 206, and a high-temperature steam end 207, a medium-temperature steam end 208 and a low-temperature steam end 209 are provided at one end of the primary heater 204.

[0037] In this embodiment: the first route is supplied to the low-temperature steam end 209, and the second route increases the temperature to about 500°C through the first-stage heater 204. A part of the outlet of the first-stage heater 204 is supplied to the medium-temperature steam end 208, and a part is heated to about 650°C through the second-stage heater 203 and supplied to the high-temperature steam end 207 steam user. The condensed water from the high-temperature steam end 207, the medium-temperature steam end 208, and the low-temperature steam end 209 are all gathered in the condenser 6.

[0038] The working principle of the present invention is as follows: the main steam from the steam generator 100 outlet to the main steam pipeline 101 is divided into three paths, one path is to enter the steam turbine unit 106 for power generation through the main steam regulating valve group 102, the second path is to flow into the condenser 105 through the bypass valve group 103, and the third path is to supply three types of steam users through the steam supply valve group 104. At the same time, the steam that cannot be consumed by the steam users will also re-enter the condenser 105 through the pipeline, and re-enter the steam generator 100 after condensation for recycling;

[0039] During the period of reduced load operation of the unit, part of the electricity generated by the generator 300 is sent to the power grid 302 through the main transformer 301 to meet the power grid demand, and the excess electricity is supplied to the electric heater 200 through the plant transformer 303, and the electric heater 200 is used to heat the low-temperature molten salt;

[0040] The electric heater 200, the high temperature molten salt storage tank 201, the high temperature molten salt pump 202, the secondary heater 203, the primary heater 204, the low temperature molten salt storage tank 205, and the low temperature molten salt pump 206 form a closed molten salt loop, wherein the molten salt in the high temperature molten salt storage tank 201 is 700°C-750°C, and the molten salt in the low temperature molten salt storage tank 205 is 300°C-350°C;

[0041] During the full-load operation of the unit, the steam supplied by the steam supply valve group 104 is 280°C and 6MPa and is divided into two routes: the first route is supplied to the low-temperature steam end 209, and the second route is heated to about 500°C through the first-stage heater 204. A part of the outlet of the first-stage heater 204 is supplied to the medium-temperature steam end 208, and a part of the outlet is heated to about 650°C through the second-stage heater 203 and supplied to the steam user of the high-temperature steam end 207. The condensed water of the high-temperature steam end 207, the medium-temperature steam end 208, and the low-temperature steam end 209 are all collected in the condenser 6;

[0042] When the steam volume increases, the high-temperature molten salt delivery capacity is increased by the high-temperature molten salt pump 202 to ensure that the steam parameters at the outlets of the first-stage heater 204 and the second-stage heater 203 are stable.

[0043] Importantly, it should be noted that the construction and arrangement of the present application shown in a number of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible, for example, the size, scale, structure, shape and proportion of various elements, and parameter values ​​such as temperature, pressure, etc., mounting arrangements, use of materials, color, directional changes, etc., without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of the execution function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other substitutions, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0044] Furthermore, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment may not be described, i.e., those features that are not relevant to the best mode presently contemplated for carrying out the invention or those features that are not relevant to implementing the invention.

[0045] It should be understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but for those of ordinary skill having the benefit of this disclosure, the development effort will be a routine task of design, fabrication, and production without undue experimentation.

[0046] 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 preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A pressurized water reactor nuclear power unit combined with a high-temperature molten salt energy storage graded steam supply system, characterized in that: include, A steam generator (100), wherein the steam generator (100) is provided with a main steam pipeline (101); an electric heater (200), wherein the electric heater (200) is arranged at one end of the steam generator (100), and a high-temperature molten salt storage tank (201) is arranged at the other end of the electric heater (200); and A generator (300) is provided at one end of a main steam pipe (101), and a main transformer (301) is provided at one end of the generator (300).

2. The pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system according to claim 1, characterized in that: The main steam pipeline (101) is provided with a main steam regulating valve group (102), a bypass valve group (103) and a steam supply valve group (104) in parallel.

3. The pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system according to claim 2, characterized in that: A condenser (105) is disposed at one end of the main steam regulating valve group (102), and a steam turbine group (106) is disposed on the condenser (105).

4. The pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system according to claim 3, characterized in that: The steam turbine unit (106) and the bypass valve unit (103) are in communication with each other, and the steam turbine unit (106) and the main steam pipeline (101) are in communication with each other.

5. The pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system according to claim 4, characterized in that: The generator (300) is connected in parallel with a main transformer (301) and a plant transformer (303), and one end of the main transformer (301) is connected in series with a power grid (302).

6. The pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system according to claim 5, characterized in that: An electric heater (200) is provided at one end of the plant transformer (303), and a high-temperature molten salt storage tank (201) and a low-temperature molten salt pump (206) are connected in parallel to the electric heater (200).

7. The pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system according to claim 6, characterized in that: A high-temperature molten salt pump (202) is provided at one end of the high-temperature molten salt storage tank (201), and a secondary heater (203) is provided at one end of the high-temperature molten salt pump (202).

8. The pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system according to claim 7, characterized in that: A primary heater (204) is disposed at one end of the secondary heater (203), and a low-temperature molten salt storage tank (205) is disposed on the primary heater (204).

9. The pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system according to claim 8, characterized in that: The low-temperature molten salt storage tank (205) is arranged at one end of the low-temperature molten salt pump (206).

10. The pressurized water reactor nuclear power unit combined with high-temperature molten salt energy storage and graded steam supply system according to claim 9, characterized in that: One end of the primary heater (204) is provided with a high-temperature steam end (207), a medium-temperature steam end (208) and a low-temperature steam end (209).

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