A molten salt electrode boiler with energy storage function

Abstract

The present invention discloses a molten salt electrode boiler with energy storage function, including a deaerator upper water pump, a deaerator, a heater feed water pump and a heater; the volume of the deaerator is configured according to the 12-hour rated steam flow, the heater is a shell and tube heat exchanger, the tube side is water, the shell side is steam, the outlet of the deaerator upper water pump is connected to the first inlet of the deaerator, the outlet of the deaerator is connected to the inlet of the heater feed water pump, the outlet of the heater feed water pump is connected to the first inlet of the heater, and the first outlet of the heater is connected to the second inlet of the deaerator. When the generator set cannot supply steam, the molten salt electrode boiler can generate steam by itself to replace the start-up boiler and meet the steam demand for the unit startup.

Description

Technical Field

[0001] The invention belongs to the field of electricity and energy storage, and specifically relates to a molten salt electrode boiler with energy storage function. Background Art

[0002] All newly built units require a starting boiler. The starting boiler provides steam for the unit during the startup of the first unit. After the unit is started and can produce stable steam, the starting boiler is in standby status. During the startup of the second and subsequent units, the unit can be started by temporary steam supply. The actual significance of the electric boiler is not very great, but it must exist as a backup steam source. The power plant also has to invest a certain amount of money every year for the standby and maintenance of the starting boiler.

[0003] With the increase in the capacity of unstable power sources such as wind power and photovoltaic power, nuclear power units also have to participate in the peak load regulation of the power grid. When nuclear power units are peak load shaving, heat loss is caused. Therefore, heat storage devices are used to store the excess electricity and heat generated by the peak load shaving of nuclear power units. The heating will produce good economic benefits.

[0004] Nuclear power units are an important way to provide zero-carbon heat. The types of steam required by a chemical park are: 1.5MPa, 300℃, 4MPa, 400℃. Pressurized water reactor nuclear power units can provide 7MPa, 280℃, which cannot meet the steam needs of the chemical park.

[0005] The power generated by the pressurized water reactor generator set is used to heat the molten salt. The high-temperature molten salt can be used to heat water to produce high-temperature steam. However, the latent heat of vaporization of water is relatively large. Using molten salt to vaporize steam at the vaporization point requires a large amount of molten salt and the operation is unstable. Directly heating low-temperature water with molten salt can easily cause the molten salt temperature to be lower than its melting point, causing system operation failures.

[0006] The specific heat of molten salt is smaller than that of water and its cost is high, but the water heat storage temperature is lower. Summary of the invention

[0007] The purpose of the present invention is to provide a molten salt electrode boiler with energy storage function in order to solve the existing problems of molten salt energy storage and heating in current power generation units.

[0008] The present invention is achieved by adopting the following technical solutions:

[0009] A molten salt electrode boiler with an energy storage function comprises a deaerator upper water pump, a deaerator, a heater feed water pump and a heater; the volume of the deaerator is configured according to a 12-hour rated steam flow rate, the heater is a shell and tube heat exchanger, the tube side is water, the shell side is steam, the outlet of the deaerator upper water pump is connected to a first inlet of the deaerator, the outlet of the deaerator is connected to an inlet of a heater feed water pump, the outlet of the heater feed water pump is connected to a first inlet of the heater, and the first outlet of the heater is connected to a second inlet of the deaerator.

[0010] A further improvement of the present invention is that it also includes a molten salt steam heating device and a low-temperature steam source. The molten salt steam heating device is a shell and tube heat exchanger, in which two sets of independent coils are arranged. The inlet of the first set of coils is connected to the first inlet of the molten salt steam heating device and the second outlet of the heater, and the outlet of the first set of coils is connected to the first outlet of the molten salt steam heating device; the inlet of the second set of coils is connected to the second inlet of the molten salt steam heating device and the outlet of the low-temperature steam source, and the outlet of the second set of coils is connected to the second outlet of the molten salt steam heating device and the inlet of the low-temperature steam source and the third inlet of the deaerator; the shell side of the molten salt steam heating device and the gap between the first set of coils and the second set of coils are filled with molten salt, the total mass of the molten salt is configured according to the rated steam flow rate of 18 hours, and the molten salt has a circulation pump to ensure the uniform temperature of the molten salt.

[0011] A further improvement of the present invention is that it also includes an electrode boiler, a molten salt electric heating device, a power management module and a high-temperature steam source; the first outlet of the molten salt steam heating device is connected to the first inlet of the electrode boiler, the outlet of the electrode boiler is divided into three branches, the first branch is connected to the first inlet of the molten salt electric heating device, and the second branch is connected to the fourth inlet of the deaerator. The first outlet of the power management module is connected to the second inlet of the electrode boiler to provide power for the electrode boiler, the second outlet of the power management module is connected to the second inlet of the molten salt electric heating device to provide power for the molten salt electric heating device, the second outlet of the molten salt electric heating device is connected to the inlet of the high-temperature steam source, and the third inlet of the molten salt electric heating device is connected to the outlet of the high-temperature steam source.

[0012] A further improvement of the present invention is that the molten salt electric heating device is arranged with two sets of independent coils in two ways and one set of electric heating device, the inlet of the first set of coils is connected to the first outlet of the electrode boiler, the outlet of the first set of coils is connected to the first outlet of the molten salt electric heating device, the first outlet of the molten salt electric heating device is divided into three branches, the first branch is connected to the user's inlet, the second branch is connected to the second inlet of the heater, and the third branch is combined with the low-temperature steam source outlet and connected to the second inlet of the molten salt steam heating device; the inlet of the second set of coils is connected to the second inlet of the molten salt electric heating device and is connected to the high-temperature steam source outlet, and the outlet of the second set of coils is connected to the second outlet of the molten salt electric heating device and is connected to the high-temperature steam source inlet; the shell side of the molten salt electric heating device and the gap between the first set of coils, the second set of coils and the electric heating device are filled with molten salt, the total mass of the molten salt is configured according to 36 times the rated steam flow rate, and the molten salt has a circulation pump to ensure the uniform temperature of the molten salt.

[0013] A further improvement of the present invention is that it also includes a reuse water tank, the third outlet of the electrode boiler is connected to the second inlet of the reuse water tank, the user's outlet is connected to the first inlet of the reuse water tank, and the second outlet of the reuse water tank is connected to the fifth inlet of the deaerator; a steam heating coil is arranged in the reuse water tank, the inlet of the steam heating coil is connected to the second inlet of the reuse water tank, and the outlet of the steam heating coil is connected to the second outlet of the reuse water tank; the water volume of the reuse water tank is configured according to the 6-hour rated steam flow rate; and a water treatment device and a water replenishing device are configured in the reuse water tank.

[0014] A further improvement of the present invention is that the rated steam flow of the boiler is configured according to the user's continuous demand flow, the rated steam pressure of the boiler is determined according to the user's maximum demand steam pressure, the heating power of the recycling water tank is configured according to the power required to heat the water of the rated steam flow from 25°C to 90°C; the heating power of the deaerator is configured according to the power required to heat the water of the rated steam flow from 90°C to 165°C; the heating power of the heater is configured according to the power required to heat the water of the rated steam flow from 165°C to 201°C; the heating power of the molten salt steam heating device is configured according to the power required to heat the water of the rated steam flow from 201°C to saturation at the rated pressure; the power of the electrode boiler is configured according to the power required to evaporate the saturated water of the rated steam flow into saturated steam; the power of the molten salt electric heating device is configured according to the power required to superheat the saturated steam of the rated steam flow to the highest temperature required by the user, and the steam coil heating power is the same as the electric power.

[0015] A further improvement of the present invention is that the function of supplying steam for unit startup is realized by the following method:

[0016] Fill the recycled water tank with water to above the minimum water level; start the deaerator water pump to fill the deaerator with water to reach the minimum water level; start the heater water pump to fill the electrode boiler with water to reach the minimum water level. During the subsequent startup and operation process,

[0017] Refill water at any time to ensure that the water level at each location is above the minimum water level;

[0018] Start the electrode boiler. When the electrode boiler generates steam, it will first supply the steam feed water to the deaerator for deoxygenation, and then supply the recycled water tank for feed water heating. The drain water from the recycled water tank will flow into the deaerator.

[0019] The electric heating in the molten salt electric heating device is put into use to superheat the steam from the electrode boiler, the steam from the molten salt electric heating device is preferentially supplied to the heater and the molten salt steam heating device to heat the feed water, and the drain from the steam preferentially supplied heater and the molten salt steam heating device flows into the deaerator;

[0020] When the whole system runs stably and the steam parameters from the molten salt electric heating device meet the user's needs, steam is supplied to the user, the user absorbs the steam heat, and the water condensed from the steam returns to the reuse water tank.

[0021] A further improvement of the present invention is that the function of converting low-temperature steam into high-temperature steam is achieved by the following method:

[0022] Isolate the steam from the molten salt electric heating device to the molten salt steam heating device and the drain from the molten salt steam heating device to the deaerator;

[0023] The steam from the low-temperature steam source is introduced into the molten salt steam heating device to heat the molten salt and further increase the feed water temperature, and the steam after heat exchange is returned to the low-temperature steam source;

[0024] The water coming out of the molten salt steam heating device is vaporized by the electrode boiler and supplied to the user after being overheated by the molten salt electric heating device.

[0025] A further improvement of the present invention is that the energy storage function is realized by the following method:

[0026] During the off-peak period of electricity consumption, the excess steam from the generator set is used to heat the feed water or steam of the molten salt electrode boiler system through a low-temperature steam source or a high-temperature steam source, and the heat is transferred to the molten salt electrode boiler;

[0027] The molten salt in the molten salt steam heating device and the molten salt electric heating device absorbs the heat of the low-temperature steam source or the high-temperature steam source, and the temperature rises, and the heat of the steam is stored in the molten salt;

[0028] The water level in the recycled water tank and deaerator is replenished to the high water level, and heated by steam from the electrode boiler and molten salt electric heating device respectively, so that the excess heat of the generator set can be stored in hot water;

[0029] During peak hours of electricity consumption, the heat stored in the recycling water tank and deaerator is released by using high-temperature water from the recycling water tank and deaerator and reducing the use of steam;

[0030] During peak electricity consumption, the heat stored in the molten salt steam heating device and the molten salt electric heating device is released by using the heat of the high-temperature molten salt in the molten salt steam heating device and the molten salt electric heating device, thereby reducing the use of low-temperature steam source and high-temperature steam source steam.

[0031] The molten salt electrode boiler with energy storage function provided by the present invention has the following obvious advantages:

[0032] (1) When the generator set cannot supply steam, the molten salt electrode boiler can generate steam by itself to replace the starting boiler and meet the steam demand for unit startup;

[0033] (2) High-temperature heat storage uses molten salt. Taking advantage of the high vaporization point of molten salt, high-temperature heat storage can be achieved under low pressure, improving the safety of heat storage and reducing costs;

[0034] (3) Low-temperature heat storage uses water. Using water at low pressure is low-cost, which overcomes the disadvantage of molten salt solidifying at low temperatures, improves the safety of heat storage, and reduces costs;

[0035] (4) Water vaporization utilizes electrode boilers, and the system occupies a small area;

[0036] (5) When the user's heating demand suddenly decreases, part of the heat supplied to the user can be stored to reduce the fluctuation of the unit and improve the safety of the unit operation;

[0037] (6) When the power generation unit is suddenly reduced, the heat stored in the heat storage system can be used to provide heat to heating users, thereby improving user satisfaction;

[0038] (7) Part of the heat of the unit can be stored during the off-peak period and released during the peak period, thereby improving the economic benefits of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a structural block diagram of a molten salt electrode boiler with energy storage function according to the present invention.

[0040] Description of reference numerals:

[0041] 1. Deaerator feed water pump, 2. Deaerator, 3. Heater feed water pump, 4. Heater, 5. Molten salt steam heating device, 6. Electrode boiler, 7. Molten salt electric heating device, 8. User, 9. Low-temperature steam source, 10. Power management module, 11. High-temperature steam source, 12. Recycled water tank. DETAILED DESCRIPTION

[0042] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0043] like Figure 1As shown, the present invention provides a molten salt electrode boiler with energy storage function, including a deaerator upper water pump 1, a deaerator 2, a heater feed water pump 3, a heater 4, a molten salt steam heating device 5, a low-temperature steam source 9, an electrode boiler 6, a molten salt electric heating device 7, a power management module 10, a high-temperature steam source 11 and a recycled water tank 12.

[0044] The volume of the deaerator 2 is configured according to the 12-hour rated steam flow rate. The heater 4 is a shell and tube heat exchanger with water on the tube side and steam on the shell side. The outlet of the water pump 1 on the deaerator is connected to the first inlet of the deaerator 2, the outlet of the deaerator 2 is connected to the inlet of the heater feed water pump 3, the outlet of the heater feed water pump 3 is connected to the first inlet of the heater 4, and the first outlet of the heater 4 is connected to the second inlet of the deaerator 2; the molten salt steam heating device 5 is a shell and tube heat exchanger, in which two sets of independent coils are arranged. The inlet of the first set of coils is connected to the first inlet of the molten salt steam heating device 5 and the heater 4, the outlet of the first set of coils is connected to the first outlet of the molten salt steam heating device 5; the inlet of the second set of coils is connected to the second inlet of the molten salt steam heating device 5 and is connected to the outlet of the low-temperature steam source 9, the outlet of the second set of coils is connected to the second outlet of the molten salt steam heating device 5 and is connected to the inlet of the low-temperature steam source 9 and the third inlet of the deaerator 2; the shell side of the molten salt steam heating device 5 and the gap between the first set of coils and the second set of coils are filled with molten salt, the total mass of the molten salt is configured according to the rated steam flow rate of 18 hours, and the molten salt has a circulation pump to ensure the uniform temperature of the molten salt; the molten salt The first outlet of the steam heating device 5 is connected to the first inlet of the electrode boiler 6. The outlet of the electrode boiler 6 is divided into three branches. The first branch is connected to the first inlet of the molten salt electric heating device 7, and the second branch is connected to the fourth inlet of the deaerator 2. The first outlet of the power management module 10 is connected to the second inlet of the electrode boiler 6 to provide power for the electrode boiler 6. The second outlet of the power management module 10 is connected to the second inlet of the molten salt electric heating device 7 to provide power for the molten salt electric heating device 7. The second outlet of the molten salt electric heating device 7 is connected to the inlet of the high-temperature steam source 11. The third outlet of the molten salt electric heating device 7 is connected to the inlet of the high-temperature steam source 11. The inlet is connected to the outlet of the high-temperature steam source 11; the third outlet of the electrode boiler 6 is connected to the second inlet of the reuse water tank 12, the outlet of the user 8 is connected to the first inlet of the reuse water tank 12, and the second outlet of the reuse water tank 12 is connected to the fifth inlet of the deaerator 2; a steam heating coil is arranged in the reuse water tank 12, the inlet of the steam heating coil is connected to the second inlet of the reuse water tank 12, and the outlet of the steam heating coil is connected to the second outlet of the reuse water tank 12; the water volume of the reuse water tank 12 is configured according to the 6-hour rated steam flow; a water treatment device and a water replenishing device are arranged in the reuse water tank 12.

[0045] The molten salt electric heating device 7 is arranged with two sets of independent coils in two ways and one set of electric heating device. The inlet of the first set of coils is connected to the first outlet of the electrode boiler 6, and the outlet of the first set of coils is connected to the first outlet of the molten salt electric heating device 7. The first outlet of the molten salt electric heating device 7 is divided into three strands, the first strand is connected to the inlet of the user 8, the second strand is connected to the second inlet of the heater 4, and the third strand is connected to the outlet of the low-temperature steam source 9 after being merged and connected to the second inlet of the molten salt steam heating device 5; the inlet of the second set of coils is connected to the second inlet of the molten salt electric heating device 7 and is connected to the outlet of the high-temperature steam source 11, and the outlet of the second set of coils is connected to the second outlet of the molten salt electric heating device 7 and is connected to the inlet of the high-temperature steam source 11; the shell side of the molten salt electric heating device 7 and the gaps between the first set of coils, the second set of coils and the electric heating device are filled with molten salt. The total mass of the molten salt is configured according to times the rated steam flow rate for 36 hours. The molten salt has a circulation pump to ensure the uniform temperature of the molten salt.

[0046] The rated steam flow of the boiler is configured according to the continuous demand flow of user 8, the rated steam pressure of the boiler is determined according to the maximum demand steam pressure of user 8, the heating power of the recycled water tank 12 is configured according to the power required to heat the water of the rated steam flow from 25°C to 90°C; the heating power of the deaerator 2 is configured according to the power required to heat the water of the rated steam flow from 90°C to 165°C; the heating power of the heater 4 is configured according to the power required to heat the water of the rated steam flow from 165°C to 201°C; the heating power of the molten salt steam heating device 5 is configured according to the power required to heat the water of the rated steam flow from 201°C to the saturation of the rated pressure; the power of the electrode boiler 6 is configured according to the power required to evaporate the saturated water of the rated steam flow into saturated steam; the power of the molten salt electric heating device 7 is configured according to the power required to superheat the saturated steam of the rated steam flow to the maximum temperature required by the user, and the steam coil heating power is the same as the electric power.

[0047] The present invention realizes the function of supplying steam for unit startup by the following method:

[0048] Refill the recycled water tank 12 with water to reach above the minimum water level; start the deaerator feed water pump 1 to replenish the deaerator 2 with water to reach the minimum water level; start the heater feed water pump 3 to replenish the electrode boiler 6 with water to reach the minimum water level; during the subsequent startup and operation process, replenish water at any time to ensure that the water level at each location is above the minimum water level;

[0049] The electrode boiler 6 is started. When the electrode boiler 6 generates steam, the steam feed water is first supplied to the deaerator 2 for deoxygenation, and then supplied to the reuse water tank 12 for feed water heating. The drain water from the reuse water tank 12 flows into the deaerator 2.

[0050] The electric heating in the molten salt electric heating device 7 is put into use to superheat the steam from the electrode boiler 6, and the steam from the molten salt electric heating device 7 is preferentially supplied to the heater 4 and the molten salt steam heating device 5 to heat the feed water, and the drain from the steam preferentially supplied heater 4 and the molten salt steam heating device 5 flows into the deaerator 2;

[0051] When the whole system runs stably and the steam parameters in the molten salt electric heating device 7 meet the needs of the user 8, steam is supplied to the user 8, the user 8 absorbs the heat of the steam, and the water condensed from the steam returns to the reuse water tank 12.

[0052] The present invention realizes the function of converting low-temperature steam into high-temperature steam by the following method:

[0053] Isolating the steam from the molten salt electric heating device 7 to the molten salt steam heating device 5 and the drain from the molten salt steam heating device 5 to the deaerator 2;

[0054] The steam from the low-temperature steam source 9 is introduced into the molten salt steam heating device 5 to heat the molten salt and further increase the feed water temperature, and the steam after heat exchange is returned to the low-temperature steam source 9;

[0055] The water coming out of the molten salt steam heating device 5 is vaporized by the electrode boiler 6 and supplied to the user 8 after being overheated by the molten salt electric heating device 7 .

[0056] The present invention realizes the energy storage function by the following method:

[0057] During the off-peak period of electricity consumption, the excess steam of the generator set is used to heat the feed water or steam of the molten salt electrode boiler system through the low-temperature steam source 9 or the high-temperature steam source 11, and the heat is transferred to the molten salt electrode boiler;

[0058] The molten salt in the molten salt steam heating device 5 and the molten salt electric heating device 7 absorbs the heat of the low-temperature steam source 9 or the high-temperature steam source 11, and the temperature rises, and the heat of the steam is stored in the molten salt;

[0059] The water levels of the recycled water tank 12 and the deaerator 2 are replenished to the high water level, and are heated by steam from the electrode boiler 6 and the molten salt electric heating device 7 respectively, so that the excess heat of the generator set is stored in hot water;

[0060] During the peak period of electricity consumption, the heat stored in the recycling water tank 12 and the deaerator 2 is released by using the high-temperature water in the recycling water tank 12 and the deaerator 2 and reducing the use of steam;

[0061] During peak electricity consumption, the heat stored in the molten salt steam heating device 5 and the molten salt electric heating device 7 is released by reducing the use of steam from the low-temperature steam source 9 and the high-temperature steam source 11.

[0062] Example:

[0063] A newly built energy base is equipped with four 1000MW Hualong One nuclear power units and two 660MW high-temperature gas-cooled reactor nuclear power units. A chemical park 6km away requires two types of steam, 1.5MPa, 280℃ and 4MPa, 400℃, and the surrounding residents need 90℃ hot water for heating.

[0064] After adopting the boiler provided by the present invention to start up, the energy base does not need to be equipped with a separate starting electric boiler, saving an investment of about 80 million yuan. Through the starting boiler with energy storage function, starting steam is provided for the unit in the starting stage of the first unit; in the normal operation stage, the Hualong One nuclear power unit and the high temperature gas-cooled reactor nuclear power unit supply steam to the energy storage system, and after adjustment by the energy storage system, the required parameters of heating can be provided to the surrounding residents and the chemical park; in the peak load stage, the excess electricity enters the energy storage system, and during the peak period of electricity consumption, the steam supply of the Hualong One nuclear power unit and the high temperature gas-cooled reactor nuclear power unit is reduced, and more electricity is generated to meet the demand for power generation; after a sudden failure of a heat user, the excess heat can also be stored through the heat storage system to provide time for the unit to adjust; after a certain generator unit fails, heat is released through the heat storage system to provide time for the unit to adjust, so as not to cause a large fluctuation in the user's heat consumption; because the heat storage system is always in a hot state, the unit starting steam source is also always in a hot standby state. When all the units are stopped, steam is produced through electric heating to meet the steam demand for re-starting the unit.

[0065] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A molten salt electrode boiler with energy storage function, characterized in that: It comprises a deaerator feed water pump (1), a deaerator (2), a heater feed water pump (3), a heater (4), a molten salt steam heating device (5) and a low-temperature steam source (9); The volume of the deaerator (2) is configured according to the 12-hour rated steam flow rate, the heater (4) is a shell and tube heat exchanger, the tube side is water, the shell side is steam, the outlet of the deaerator upper water pump (1) is connected to the first inlet of the deaerator (2), the outlet of the deaerator (2) is connected to the inlet of the heater feed water pump (3), the outlet of the heater feed water pump (3) is connected to the first inlet of the heater (4), and the first outlet of the heater (4) is connected to the second inlet of the deaerator (2); The molten salt steam heating device (5) is a shell and tube heat exchanger, in which two sets of independent coils are arranged. The inlet of the first set of coils is connected to the first inlet of the molten salt steam heating device (5) and the second outlet of the heater (4), and the outlet of the first set of coils is connected to the first outlet of the molten salt steam heating device (5); the inlet of the second set of coils is connected to the second inlet of the molten salt steam heating device (5) and the outlet of the low-temperature steam source (9), and the outlet of the second set of coils is connected to the second outlet of the molten salt steam heating device (5) and the inlet of the low-temperature steam source (9) and the third inlet of the deaerator (2); the shell side of the molten salt steam heating device (5) and the gap between the first set of coils and the second set of coils are filled with molten salt, the total mass of the molten salt is configured according to the rated steam flow rate of 18 hours, and the molten salt is provided with a circulation pump to ensure the uniform temperature of the molten salt.

2. The molten salt electrode boiler with energy storage function according to claim 1, characterized in that: It also includes an electrode boiler (6), a molten salt electric heating device (7), a power management module (10) and a high-temperature steam source (11); the first outlet of the molten salt steam heating device (5) is connected to the first inlet of the electrode boiler (6), the outlet of the electrode boiler (6) is divided into three branches, the first branch is connected to the first inlet of the molten salt electric heating device (7), and the second branch is connected to the fourth inlet of the deaerator (2); the first outlet of the power management module (10) is connected to the second inlet of the electrode boiler (6) to provide power for the electrode boiler (6); the second outlet of the power management module (10) is connected to the second inlet of the molten salt electric heating device (7) to provide power for the molten salt electric heating device (7); the second outlet of the molten salt electric heating device (7) is connected to the inlet of the high-temperature steam source (11), and the third inlet of the molten salt electric heating device (7) is connected to the outlet of the high-temperature steam source (11).

3. The molten salt electrode boiler with energy storage function according to claim 2, characterized in that: The molten salt electric heating device (7) is arranged with two sets of independent coils in two ways and one set of electric heating device. The inlet of the first set of coils is connected to the first outlet of the electrode boiler (6), and the outlet of the first set of coils is connected to the first outlet of the molten salt electric heating device (7). The first outlet of the molten salt electric heating device (7) is divided into three streams, the first stream is connected to the inlet of the user (8), the second stream is connected to the second inlet of the heater (4), and the third stream is combined with the outlet of the low-temperature steam source (9) and connected to the second inlet of the molten salt steam heating device (5); the inlet of the second set of coils is connected to the second inlet of the molten salt electric heating device (7) and is connected to the outlet of the high-temperature steam source (11), and the outlet of the second set of coils is connected to the second outlet of the molten salt electric heating device (7) and is connected to the inlet of the high-temperature steam source (11); the shell side of the molten salt electric heating device (7) and the gaps between the first set of coils, the second set of coils and the electric heating device are filled with molten salt, the total mass of the molten salt is configured according to times the rated steam flow rate for 36 hours, and the molten salt is provided with a circulation pump to ensure the uniform temperature of the molten salt.

4. The molten salt electrode boiler with energy storage function according to claim 2, characterized in that: The invention also comprises a recycling water tank (12), wherein the third outlet of the electrode boiler (6) is connected to the second inlet of the recycling water tank (12), the outlet of the user (8) is connected to the first inlet of the recycling water tank (12), and the second outlet of the recycling water tank (12) is connected to the fifth inlet of the deaerator (2); a steam heating coil is arranged in the recycling water tank (12), the inlet of the steam heating coil is connected to the second inlet of the recycling water tank (12), and the outlet of the steam heating coil is connected to the second outlet of the recycling water tank (12); the water volume of the recycling water tank (12) is configured according to the rated steam flow rate of 6 hours; and a water treatment device and a water replenishing device are configured in the recycling water tank (12).

5. The molten salt electrode boiler with energy storage function according to claim 3, characterized in that: The rated steam flow of the boiler is configured according to the continuous demand flow of the user (8), the rated steam pressure of the boiler is determined according to the maximum demand steam pressure of the user (8), the heating power of the recycling water tank (12) is configured according to the power required to heat the water of the rated steam flow from 25°C to 90°C; the heating power of the deaerator (2) is configured according to the power required to heat the water of the rated steam flow from 90°C to 165°C; the heating power of the heater (4) is configured according to the power required to heat the water of the rated steam flow from 165°C to 201°C; the heating power of the molten salt steam heating device (5) is configured according to the power required to heat the water of the rated steam flow from 201°C to the saturation of the rated pressure; the power of the electrode boiler (6) is configured according to the power required to evaporate the saturated water of the rated steam flow into saturated steam; the power of the molten salt electric heating device (7) is configured according to the power required to superheat the saturated steam of the rated steam flow to the maximum temperature required by the user, and the steam coil heating power is the same as the electric power.

6. The molten salt electrode boiler with energy storage function according to claim 4, characterized in that: The function of supplying steam for unit startup is realized by the following methods: Refill the recycled water tank (12) with water to reach above the minimum water level; start the deaerator water supply pump (1) to replenish the deaerator (2) with water to reach the minimum water level; start the heater water supply pump (3) to replenish the electrode boiler (6) with water to reach the minimum water level; during the subsequent startup and operation process, replenish water at any time to ensure that the water level at each location is above the minimum water level; The electrode boiler (6) is started. When the electrode boiler (6) generates steam, the steam feed water is first supplied to the deaerator (2) for deoxygenation, and then supplied to the recycling water tank (12) for heating. The drain water from the recycling water tank (12) flows into the deaerator (2); The electric heating in the molten salt electric heating device (7) is put into use to superheat the steam from the electrode boiler (6), the steam from the molten salt electric heating device (7) is preferentially supplied to the heater (4) and the molten salt steam heating device (5) to heat the feed water, and the drain from the steam preferentially supplied heater (4) and the molten salt steam heating device (5) flows into the deaerator (2); When the whole system operates stably and the steam parameters in the molten salt electric heating device (7) meet the needs of the user (8), steam is supplied to the user (8), the user (8) absorbs the heat of the steam, and the water condensed from the steam returns to the recycling water tank (12).

7. The molten salt electrode boiler with energy storage function according to claim 4, characterized in that: The function of converting low-temperature steam into high-temperature steam is achieved by the following methods: Isolating the steam from the molten salt electric heating device (7) to the molten salt steam heating device (5) and the drain from the molten salt steam heating device (5) to the deaerator (2); The steam of the low-temperature steam source (9) is introduced into the molten salt steam heating device (5) to heat the molten salt and further increase the feed water temperature, and the steam after heat exchange is returned to the low-temperature steam source (9); The water coming out of the molten salt steam heating device (5) is vaporized by the electrode boiler (6), and is supplied to the user (8) after being overheated by the molten salt electric heating device (7).

8. The molten salt electrode boiler with energy storage function according to claim 4, characterized in that: The energy storage function is achieved through the following methods: During the off-peak period of electricity consumption, the excess steam of the generator set is used to heat the feed water or steam of the molten salt electrode boiler system through the low-temperature steam source (9) or the high-temperature steam source (11), and the heat is transferred to the molten salt electrode boiler; The molten salt in the molten salt steam heating device (5) and the molten salt electric heating device (7) absorbs the heat of the low-temperature steam source (9) or the high-temperature steam source (11), and the temperature rises, and the heat of the steam is stored in the molten salt; The water levels of the recycled water tank (12) and the deaerator (2) are replenished to a high water level, and are heated by steam from the electrode boiler (6) and the molten salt electric heating device (7), respectively, so that the excess heat of the generator set is stored in hot water; During the peak period of electricity consumption, the heat stored in the recycling water tank (12) and the deaerator (2) is released by using the high-temperature water in the recycling water tank (12) and the deaerator (2) to reduce the use of steam; During peak electricity consumption, the heat stored in the molten salt steam heating device (5) and the molten salt electric heating device (7) is released by reducing the use of steam from the low-temperature steam source (9) and the high-temperature steam source (11).

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