Device for realizing peak regulation of power station by using molten salt heat storage

Abstract

The utility model relates to a device for realizing peak regulation of a power station by utilizing molten salt heat storage, which comprises a molten salt heat storage and release system, a steam generation system and a traditional power generation system, the steam generation system is a steam generator, and the traditional power generation system comprises a boiler, a steam turbine, a generator, a condenser, a feed pump and a steam valve. The molten salt heat storage and release system comprises a molten salt tank, a molten salt heat storage pump, a first molten salt valve, a molten salt reflux pump and a second molten salt valve, and the molten salt tank comprises a molten salt outer tank body, a heat preservation and insulation layer, a low-temperature inner tank body, a heating inner tank body, a high-temperature inner tank body and a steam pipeline. Fused salt preheating, fused salt heating and fused salt conveying heat source separation are achieved, the fused salt heating speed is increased, and the utilization rate of high-temperature steam is increased.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of energy -conserving and environment -protective technology more specifically, relate to a device for realizing power station peak shaving by using molten salt heat storage. BACKGROUND

[0002] With the global industrialization of rapid development, the periodic variation of power grid load exists in the day peak and the night low, and the peak-valley difference of electricity load can reach 30% to 40% of the maximum power output. The existence of peak-valley difference causes certain difficulty to power generation and power dispatching, and brings certain risk to power grid operation. At the same time, in order to meet the maximum load requirement of power grid, the construction cost of power grid is also greatly increased, and the utilization efficiency is low.

[0003] Chinese patent 201720780491.5 discloses a device for realizing power station peak shaving by using molten salt heat storage, which utilizes the high temperature heat storage capacity of molten salt to store the heat energy of the surplus steam of the boiler, and reconverts it into high temperature and high pressure steam for power generation when needed, so as to adapt to the peak shaving demand of power station, especially suitable for stable operation of power station under ultra-low load, has the advantages of simple system, convenient peak shaving, high economy and small influence on the original system; but there are still deficiencies, for example, in the above-mentioned scheme, the low temperature molten salt and the high temperature molten salt are placed in the same container, when the high temperature steam passes through the molten salt tank, because there are molten salts of multiple temperatures in the molten salt tank, the volume of high temperature molten salt is larger and larger, because the high temperature steam no longer exchanges heat with the high temperature molten salt, the contact area between the high temperature steam and the low temperature molten salt becomes smaller and smaller, and the heat exchange efficiency becomes slower and slower, the high temperature steam repeatedly flows through the molten salt tank, which leads to slow heating speed of the molten salt, low heat storage efficiency, and large heat loss of the steam in the repeated flow process, the utility model puts forward a new solution to the above problems. UTILITY MODEL CONTENTS

[0004] In view of the problems existing in the prior art, the purpose of the utility model is to provide a device for realizing power station peak shaving by using molten salt heat storage, so as to solve the technical problems mentioned in the background art.

[0005] In order to solve the above problems, the utility model adopts the following technical scheme.

[0006] A device for realizing power station peak shaving by using molten salt heat storage, comprising a molten salt heat storage and release system, a steam generation system and a traditional power generation system, the steam generation system is a steam generator, the traditional power generation system comprises a boiler, a steam turbine, a generator, a condenser, a feed water pump and a steam valve, the molten salt heat storage and release system comprises a molten salt tank, a molten salt heat storage pump, a first molten salt valve, a molten salt backflow pump and a second molten salt valve, wherein

[0007] The molten salt tank comprises a molten salt outer tank body, a heat preservation layer, a low-temperature inner tank body, a heating inner tank body, a high-temperature inner tank body and a steam pipeline, the low-temperature inner tank body, the heating inner tank body and the high-temperature inner tank body are located in the molten salt outer tank body, the heat preservation layer is arranged between the low-temperature inner tank body, the heating inner tank body, the high-temperature inner tank body and the molten salt outer tank body, a molten salt input end of the low-temperature inner tank body is communicated with an output end of the molten salt backflow pump, a molten salt output end of the low-temperature inner tank body is communicated with an input end of the heating inner tank body, an output end of the heating inner tank body is communicated with an input end of the high-temperature inner tank body, an output end of the high-temperature inner tank body is communicated with an input end of the molten salt heat storage pump, an output end of the molten salt heat storage pump and an input end of the molten salt backflow pump are communicated with the steam generator, and one end of the steam pipeline passes through the heating inner tank body and the low-temperature inner tank body in sequence and the steam pipeline is communicated with the steam turbine.

[0008] Preferably, the low-temperature inner tank body and the heating inner tank body are communicated through a molten salt conveying pump one arranged therebetween, and the heating inner tank body and the high-temperature inner tank body are communicated through a molten salt conveying pump two arranged therebetween.

[0009] Preferably, in any of the above solutions, the molten salt conveying pump one and a molten salt input end of the steam generator are communicated through a branch pipe one arranged therebetween, the branch pipe one is provided with a control valve one, the molten salt conveying pump two and the molten salt input end of the steam generator are communicated through a branch pipe two arranged therebetween, the branch pipe two is provided with a control valve two, the molten salt input end of the heating inner tank body is provided with a control valve three, and the molten salt input end of the high-temperature inner tank body is provided with a control valve four.

[0010] Preferably, in any of the above solutions, the molten salt outer tank body is provided with thermometers for measuring temperatures in the low-temperature inner tank body, the heating inner tank body and the high-temperature inner tank body.

[0011] Preferably, in any of the above solutions, the heating inner tank body is provided with a plurality of groups of steam branch pipes, and the steam pipeline is communicated with the steam branch pipes.

[0012] Preferably, in any of the above solutions, the steam pipeline is provided with a drain valve.

[0013] Compared with the prior art, the molten salt tank has the following advantages:

[0014] The design of the molten salt heat storage and release system in the utility model, different temperature molten salts are placed in the low temperature inner tank body, the heating inner tank body and the high temperature inner tank body, the steam generated by the boiler heats the molten salts in the low temperature inner tank body and the heating inner tank body through the steam pipeline, the molten salts in the high temperature state are transported into the high temperature inner tank body, the high temperature steam first heats the molten salts between the high temperature and the low temperature, and then the residual heat is used to further heat the low temperature molten salts, the utilization rate of the high temperature steam is improved, the three kinds of temperature gradient molten salts are separately stored, the heat exchange between the three kinds of temperature gradient molten salts is reduced, the high temperature molten salts are used as heat sources for the steam generator, the separation of the molten salt preheating, the molten salt heating and the molten salt heat source transportation is realized, the molten salt heating speed is improved, and the utilization rate of the high temperature steam is improved. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is an overall structure schematic view of the device for realizing power station peak regulation by using molten salt heat storage.

[0016] Mark explanation in the drawing:

[0017] 1, molten salt heat storage and release system; 2, steam generation system; 3, traditional power generation system; 301, boiler; 302, steam turbine; 303, generator; 304, condenser; 305, feed water pump; 306, steam valve; 101, molten salt heat storage pump; 102, molten salt backflow pump; 103, molten salt outer tank body; 104, heat preservation and insulation layer; 105, low temperature inner tank body; 106, heating inner tank body; 107, high temperature inner tank body; 108, steam pipeline; 109, molten salt conveying pump one; 110, molten salt conveying pump two; 111, branch pipe one; 112, control valve one; 113, branch pipe two; 114, control valve two; 115, control valve three; 116, control valve four; 117, thermometer; 118, steam branch pipe; 119, trap. DETAILED DESCRIPTION

[0018] The technical scheme in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model; obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments, and all other embodiments obtained by the ordinary skilled in the art without creative labor based on the embodiments in the utility model belong to the protection scope of the utility model.

[0019] Embodiment:

[0020] Please refer to Figure 1The utility model relates to a device for realizing power station peak shaving by molten salt heat storage, which comprises a molten salt heat storage and release system 1, a steam generation system 2 and a traditional power generation system 3.

[0021] The molten salt tank comprises a molten salt outer tank body 103, a heat preservation and insulation layer 104, a low-temperature inner tank body 105, a heating inner tank body 106, a high-temperature inner tank body 107 and a steam pipeline 108. The low-temperature inner tank body 105, the heating inner tank body 106 and the high-temperature inner tank body 107 are located in the molten salt outer tank body 103. The heat preservation and insulation layer 104 is arranged between the low-temperature inner tank body 105, the heating inner tank body 106, the high-temperature inner tank body 107 and the molten salt outer tank body 103. The molten salt input end of the low-temperature inner tank body 105 is in communication with the output end of the molten salt backflow pump 102. The molten salt output end of the low-temperature inner tank body 105 is in communication with the input end of the heating inner tank body 106. The output end of the heating inner tank body 106 is in communication with the input end of the high-temperature inner tank body 107. The output end of the high-temperature inner tank body 107 is in communication with the input end of the molten salt heat storage pump 101. The output end of the molten salt heat storage pump 101 and the input end of the molten salt backflow pump 102 are in communication with the steam generator. One end of the steam pipeline 108 passes through the heating inner tank body 106 and the low-temperature inner tank body 105 in sequence, and the steam pipeline 108 is in communication with the steam turbine 302.

[0022] The molten salt heat storage and release system 1 is designed to store molten salts of different temperatures in the low-temperature inner tank body 105, the heating inner tank body 106 and the high-temperature inner tank body 107. The steam generated by the boiler 301 is used to heat the molten salts in the low-temperature inner tank body 105 and the heating inner tank body 106 through the steam pipeline 108. The molten salt heated to a high temperature is delivered to the high-temperature inner tank body 107. The high-temperature steam is used to heat the molten salt between the high temperature and the low temperature first, and then the residual heat is used to further heat the low-temperature molten salt. The utilization rate of the high-temperature steam is improved. The molten salts of three temperature gradients are stored separately, the heat exchange between the molten salts of the three temperature gradients is reduced, the high-temperature molten salt is used to deliver heat to the steam generator, the separation of molten salt preheating, molten salt heating and molten salt heat delivery is realized, the speed of heating the molten salt is improved, and the utilization rate of the high-temperature steam is improved.

[0023] In the embodiment, the low-temperature inner tank 105 is communicated with the heating inner tank 106 through the molten salt conveying pump one 109, and the heating inner tank 106 is communicated with the high-temperature inner tank 107 through the molten salt conveying pump two 110; the molten salt is conveyed by the molten salt conveying pump one 109 and the molten salt conveying pump two 110, so as to ensure the working temperature of the molten salt in the low-temperature inner tank 105, the heating inner tank 106 and the high-temperature inner tank 107.

[0024] In the embodiment, the molten salt conveying pump one 109 is communicated with the molten salt input end of the steam generator through the branch pipe one 111, the branch pipe one 111 is provided with the control valve one 112, the molten salt conveying pump two 110 is communicated with the molten salt input end of the steam generator through the branch pipe two 113, the branch pipe two 113 is provided with the control valve two 114, the molten salt input end of the heating inner tank 106 is provided with the control valve three 115, and the molten salt input end of the high-temperature inner tank 107 is provided with the control valve four 116; the branch pipe one 111 and the branch pipe two 113 can be used to convey the molten salt at a lower temperature into the steam generator to generate, so as to meet the requirements of different energy storage and energy release.

[0025] In the embodiment, the temperature meter 117 for measuring the temperature in the low-temperature inner tank 105, the heating inner tank 106 and the high-temperature inner tank 107 is arranged on the molten salt outer tank 103; the temperature in the low-temperature inner tank 105, the heating inner tank 106 and the high-temperature inner tank 107 is monitored by the temperature meter 117.

[0026] In the embodiment, a plurality of steam branch pipes 118 are arranged in the heating inner tank 106, and the steam pipeline 108 is communicated with the steam branch pipes 118; the steam branch pipes 118 are used to increase the contact area between the high-temperature steam and the molten salt in the heating inner tank 106, so as to provide heat exchange efficiency.

[0027] In the embodiment, the steam pipeline 108 is provided with the drain valve 119.

[0028] The working process of the utility model is as follows:

[0029] When the power plant needs to reduce the load, the boiler 301 will lead the surplus steam from the outlet of the boiler 301, the surplus steam is sent to the heating inner tank 106, the low temperature inner tank 105 through the steam pipeline 108, and the heat is released in the tank, at the same time, the control valve one 112 and the control valve two 114 are closed, the control valve three 115, the control valve four 116 are in the open state, the molten salt conveying pump one 109, the molten salt conveying pump two 110 are opened in time according to the molten salt temperature in the low temperature inner tank 105, the heating inner tank 106, the low temperature molten salt flows into the heating inner tank 106 from the low temperature inner tank 105 through the molten salt conveying pump one 109, the molten salt heated to high temperature in the heating inner tank 106 flows into the high temperature inner tank 107 through the molten salt conveying pump two 110 for storage, when the storage in the high temperature inner tank 107 is full, the molten salt conveying pump two 110 stops running, the molten salt heated to high temperature in the heating inner tank 106 is temporarily stored in the heating inner tank 106, when the molten salt in the heating inner tank 106 is all heated to high temperature, the molten salt conveying pump one 109 stops running, the high temperature steam continues to heat the molten salt in the low temperature inner tank 105, until the molten salt in the low temperature inner tank 105 becomes high temperature molten salt, the steam after heat release in the above process goes to the condenser 304 to condense to form condensed water, then the condensed water is sent into the boiler 301 again through the feed water pump 305, realizing the recycling of the feed water, at the same time, the steam still has high excess temperature when flowing through the heating inner tank 106, the low temperature inner tank 105 after heat release in the steam pipeline 108, which can prevent the molten salt from condensing.

[0030] When the power plant needs to increase the load, the control valve one 112 is opened, the control valve two 114, the control valve three 115 and the control valve four 116 are in the closed state, the molten salt conveying pump one 109 is opened, the high-temperature molten salt flows into the steam generator through the molten salt conveying pump one 109 and the branch pipe one 111, and the feed water pump 305 sends part of the feed water to the steam generator. In the steam generator, the high-temperature molten salt heats the feed water, the molten salt gradually cools down, the feed water is heated to form steam, the steam formed in the steam generator goes to the steam turbine 302 to drive the steam turbine 302 to do work, the steam turbine 302 drives the generator 303 to generate electricity, and the molten salt after flowing through the steam generator is conveyed to the low-temperature inner tank body 105. When the low-temperature inner tank body 105 reaches a certain low temperature, the control valve one 112, the control valve three 115 and the control valve four 116 are closed, the molten salt conveying pump one 109 stops running, the control valve two 114 is opened, the molten salt conveying pump two 110 runs, the high-temperature molten salt flows into the steam generator through the molten salt conveying pump two 110 and the branch pipe two 113, and the feed water pump 305 sends part of the feed water to the steam generator. In the steam generator, the high-temperature molten salt heats the feed water, the molten salt gradually cools down, the feed water is heated to form steam, the steam formed in the steam generator goes to the steam turbine 302 to drive the steam turbine 302 to do work, the steam turbine 302 drives the generator 303 to generate electricity, and the molten salt after flowing through the steam generator is conveyed to the low-temperature inner tank body 105. When the molten salt conveying in the heating inner tank body 106 is completed, the control valve one 112, the control valve two 114 and the control valve four 116 are closed, the molten salt conveying pump two 110 stops running, the control valve three 115 is opened, and the molten salt conveying pump one 109 runs to convey the molten salt in the low-temperature inner tank body 105 to the heating inner tank body 106, and at the same time, the molten salt in the high-temperature inner tank body 107 is conveyed to the steam generator, and the molten salt after flowing through the steam generator is conveyed to the low-temperature inner tank body 105.

[0031] The molten salt heat storage and release system 1 is designed to store molten salts of different temperatures in the low-temperature inner tank body 105, the heating inner tank body 106 and the high-temperature inner tank body 107. The steam generated by the boiler 301 heats the molten salts in the low-temperature inner tank body 105 and the heating inner tank body 106 through the steam pipeline 108, and the molten salt at a high temperature is conveyed to the high-temperature inner tank body 107. The high-temperature steam first heats the molten salt between high and low temperatures, and then further heats the low-temperature molten salt by using the residual heat, thereby improving the utilization rate of the high-temperature steam. The molten salts of three temperature gradients are stored separately, the heat exchange between the molten salts of three temperature gradients is reduced, the high-temperature molten salt is used as a heat source for the steam generator, the separation of molten salt preheating, molten salt heating and molten salt heat source conveying is realized, the speed of heating the molten salt is improved, and the utilization rate of the high-temperature steam is improved.

[0032] The above merely describes a preferred embodiment of the present application; the scope of protection of the present application is not limited thereto. Any skilled person in the art, according to the technical scheme and improvement concept of the present application, makes equivalent replacement or change within the technical range disclosed by the present application, which should be covered in the scope of protection of the present application.

Claims

1. A device for realizing power station peak shaving by using molten salt heat storage, comprising a molten salt heat storage and release system (1), a steam generation system (2) and a traditional power generation system (3), the steam generation system (2) is a steam generator, the traditional power generation system (3) comprises a boiler (301), a steam turbine (302), a generator (303), a condenser (304), a feed water pump (305) and a steam valve (306), characterized in that: The molten salt heat storage and release system (1) comprises a molten salt tank, a molten salt heat storage pump (101), and a molten salt return pump (102), wherein The molten salt tank comprises a molten salt outer tank body (103), a heat preservation and insulation layer (104), a low-temperature inner tank body (105), a heating inner tank body (106), a high-temperature inner tank body (107), and a steam pipeline (108). The low-temperature inner tank body (105), the heating inner tank body (106), and the high-temperature inner tank body (107) are located in the molten salt outer tank body (103). The heat preservation and insulation layer (104) is arranged between the low-temperature inner tank body (105), the heating inner tank body (106), the high-temperature inner tank body (107), and the molten salt outer tank body (103). The molten salt input end of the low-temperature inner tank body (105) is in communication with the output end of the molten salt return pump (102). The molten salt output end of the low-temperature inner tank body (105) is in communication with the input end of the heating inner tank body (106). The output end of the heating inner tank body (106) is in communication with the input end of the high-temperature inner tank body (107). The output end of the high-temperature inner tank body (107) is in communication with the input end of the molten salt heat storage pump (101). The output end of the molten salt heat storage pump (101) and the input end of the molten salt return pump (102) are in communication with the steam generator. One end of the steam pipeline (108) sequentially penetrates through the heating inner tank body (106) and the low-temperature inner tank body (105), and the steam pipeline (108) is in communication with the steam turbine (302).

2. The device for peak shaving of power station by using molten salt heat storage according to claim 1, characterized in that: The low-temperature inner tank body (105) and the heating inner tank body (106) are in communication through the arranged molten salt conveying pump one (109). The heating inner tank body (106) and the high-temperature inner tank body (107) are in communication through the arranged molten salt conveying pump two (110).

3. The device for peak shaving of power station by using molten salt heat storage according to claim 2, characterized in that: The molten salt conveying pump one (109) and the molten salt input end of the steam generator are in communication through the arranged branch pipe one (111). The branch pipe one (111) is provided with a control valve one (112). The molten salt conveying pump two (110) and the molten salt input end of the steam generator are in communication through the arranged branch pipe two (113). The branch pipe two (113) is provided with a control valve two (114). The molten salt input end of the heating inner tank body (106) is provided with a control valve three (115). The molten salt input end of the high-temperature inner tank body (107) is provided with a control valve four (116).

4. The device for peak shaving of power station by using molten salt heat storage according to claim 3, characterized in that: The molten salt outer tank body (103) is provided with a thermometer (117) for measuring the temperature in the low-temperature inner tank body (105), the heating inner tank body (106), and the high-temperature inner tank body (107).

5. The device for peak shaving of power station by using molten salt heat storage according to claim 1, characterized in that: The heating inner tank body (106) is provided with a plurality of groups of steam branch pipes (118). The steam pipeline (108) is in communication with the steam branch pipes (118).

6. The device for peak shaving of power station by using molten salt heat storage according to claim 1, characterized in that: The steam pipeline (108) is provided with a drain valve (119).

Images