Valley electricity fused salt energy storage coupled high-temperature heat pump steam supply system

Abstract

The utility model provides a valley electricity fused salt energy storage coupling high-temperature heat pump steam supply system, and belongs to the field of steam generation equipment. The system comprises a high-temperature heat pump unit steam supply unit, a valley electricity fused salt energy storage steam supply unit and a steam condensate recovery unit. Recycled steam condensate water serves as a condensate water source, high-temperature water is generated through the high-temperature heat pump unit, low-pressure steam is obtained through flash evaporation of the flash evaporation tank, and then the low-pressure steam is compressed into steam needed in the production process through the steam compressor. The fused salt tank is used for storing heat through fused salt heat storage during the off-peak electricity period and supplying steam at the same time, or the stored heat is used for supplying steam during the non-off-peak electricity period; the high-temperature heat pump unit steam supply unit and the valley electricity fused salt energy storage steam supply unit form two parallel steam supply systems for steam complementary supply, and the stability of steam supply is improved.

Description

Technical Field

[0001] The utility model belongs to the field of steam generating equipment, and in particular relates to a valley electric molten salt energy storage coupled high-temperature heat pump steam supply system. Background Art

[0002] Steam is a commonly used heat medium in many industrial production processes, and is also an indispensable heat source in life and process production. The steam source of some factories is provided by coal-fired boilers in the municipal pipeline network. Coal-fired boilers will produce a certain amount of polluting gases while producing steam, and the cost of purchasing steam is high. After the steam condensate in the factory is recovered, it needs to be cooled and then recycled as pure water. At present, many factories do not fully utilize the waste heat of steam condensate during cooling treatment, resulting in heat waste.

[0003] Molten salt energy storage technology uses the temperature difference of molten salt during the heating and cooling process to store thermal energy. Compared with the traditional steam thermal storage system, the molten salt system has the advantages of simple design, low cost, high heat storage density, small footprint, high waste heat utilization efficiency, and high power generation efficiency.

[0004] At present, the national power supply grid has the problem of excessive difference between peak and valley electricity. Usually, electricity consumption peaks during the day and is lower at night, when electricity prices are relatively cheap. Vigorously promoting the use of peak-shifting and valley-filling electricity in production can reduce production costs.

[0005] Valley electricity thermal storage technology is one of the emerging heating technologies in recent years. It uses low-valley electricity at night to heat the energy storage medium, converts the surplus valley electricity at night into thermal energy for storage, and provides heating when the heat is needed. Since molten salt thermal storage has a high energy density and can store a large amount of energy, molten salt can be used to store heat when the electricity price is at the valley level at night. Utility Model Content

[0006] In view of this, the utility model provides a valley electricity molten salt energy storage coupled with a high-temperature heat pump steam supply system. The system combines valley electricity molten salt energy storage technology with high-temperature heat pump technology for use in the steam generation process, thereby improving the stability of the steam supply, having cost-reduction and energy-saving effects in the steam generation and supply process, and improving the utilization rate of waste heat of steam condensed water.

[0007] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is a valley electric molten salt energy storage coupled high-temperature heat pump steam supply system, including a high-temperature heat pump unit steam supply unit, a valley electric molten salt energy storage steam supply unit, and a steam condensate recovery unit;

[0008] The high-temperature heat pump unit steam supply unit includes a compressor, an evaporator, a throttle valve, a condenser, a flash tank, and a steam compressor. The compressor, the evaporator, the throttle valve, and the condenser form a high-temperature heat pump unit loop. There is a working medium in the loop. The water inlet of the evaporator is connected to the condensate supply pipeline, the water outlet of the evaporator is connected to the inlet of the flash tank, the steam outlet of the flash tank is connected to the inlet of the steam compressor, and the outlet of the steam compressor is connected to the steam supply pipe;

[0009] The valley electric molten salt energy storage steam supply unit comprises a molten salt tank, a molten salt pump, and a steam generator. An electric heating pipe is arranged in the molten salt tank. The molten salt tank is connected to the molten salt pump and the steam generator in a loop in sequence.

[0010] The steam condensate recovery unit comprises a steam condensate tank, the saturated water outlet of the flash tank is connected to the steam condensate tank, the water inlet of the steam generator is connected to the water outlet of the steam condensate tank, and the steam outlet of the steam generator is connected to the steam supply pipe.

[0011] Furthermore, a vapor-liquid separation tank is provided between the steam outlet of the steam generator and the steam supply pipe, the inlet of the vapor-liquid separation tank is connected to the steam outlet of the steam generator, the steam outlet of the vapor-liquid separation tank is connected to the steam supply pipe, and the condensed water outlet of the vapor-liquid separation tank is connected to the steam condensate tank.

[0012] Furthermore, a first water pump is provided on the connecting pipe between the steam condensate tank and the steam generator.

[0013] Furthermore, the steam condensate tank is connected to the water inlet of the condenser, and the water outlet of the condenser is connected to the condensate recovery pipeline.

[0014] Furthermore, a second water pump is provided on the connecting pipe between the steam condensate tank and the condenser.

[0015] Furthermore, a reflux pipe is provided on the upper part of the steam condensate tank, the reflux pipe is connected to the condensate recovery pipeline, and a float valve is provided on the reflux pipe.

[0016] Furthermore, there are multiple molten salt tanks, and the multiple molten salt tanks are arranged in parallel.

[0017] Compared with the prior art, the beneficial technical effects of the utility model are:

[0018] 1. The valley electric molten salt energy storage coupled high-temperature heat pump steam supply system of the utility model uses the recovered steam condensate as the condensate source, utilizes the high-temperature heat pump unit to generate high-temperature water, flashes out low-pressure steam through the flash tank, and then compresses it into the steam required in the production process through the steam compressor.

[0019] 2. The valley power molten salt energy storage coupled high-temperature heat pump steam supply system of the utility model utilizes a molten salt tank to store heat through molten salt heat storage during valley power periods and supply steam at the same time, or utilizes the stored heat to supply steam during non-valley power periods.

[0020] 3. In the valley electric molten salt energy storage coupled high-temperature heat pump steam supply system of the utility model, the high-temperature heat pump unit steam supply unit and the valley electric molten salt energy storage steam supply unit form two parallel steam supply systems for complementary steam supply, thereby improving the stability of steam supply.

[0021] 4. The steam condensate generated by the steam supply unit of the high-temperature heat pump unit in the valley electric molten salt energy storage coupled high-temperature heat pump steam supply system of the utility model is stored in a steam condensate tank for steam generation of the valley electric molten salt energy storage steam supply unit, thereby improving the utilization rate of waste heat of the steam condensate. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the valley electric molten salt energy storage coupled with a high-temperature heat pump steam supply system of the utility model;

[0023] Figure numerals: 1-compressor, 2-evaporator, 3-throttle valve, 4-condenser, 5-flash tank, 6-steam compressor, 7-steam condensate tank, 8-molten salt tank, 9-electric heating tube, 10-molten salt pump, 11-steam generator, 12-vapor-liquid separation tank, 13-first water pump, 14-second water pump. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below through preferred embodiments.

[0025] See also Figure 1 As shown, this embodiment provides a valley electricity molten salt energy storage coupled high-temperature heat pump steam supply system, including a high-temperature heat pump unit steam supply unit, a valley electricity molten salt energy storage steam supply unit, and a steam condensate recovery unit.

[0026] The steam supply unit of the high-temperature heat pump unit includes a compressor 1, an evaporator 2, a throttle valve 3, a condenser 4, a flash tank 5, and a steam compressor 61. The compressor 1, the evaporator 2, the throttle valve 3, and the condenser 4 form a high-temperature heat pump unit loop, in which there is a working medium. The water inlet of the evaporator 2 is connected to the condensate supply pipeline, the water outlet of the evaporator 2 is connected to the inlet of the flash tank 5, the steam outlet of the flash tank 5 is connected to the inlet of the steam compressor 61, and the outlet of the steam compressor 61 is connected to the steam supply pipe. The steam supply unit of the high-temperature heat pump unit uses the steam condensate recovered in the production process as a condensate source, uses the high-temperature heat pump unit to generate high-temperature water, flashes low-pressure steam through the flash tank 5, and then compresses it into the steam required in the production process through the steam compressor 61, thereby improving the utilization rate of the steam condensate.

[0027] The valley electricity molten salt energy storage steam supply unit includes a molten salt tank 8, a molten salt pump 10, and a steam generator 11. The molten salt tank 8 is provided with an electric heating pipe 9, and the molten salt tank 8 is connected to the molten salt pump 10 and the steam generator 11 in a loop in sequence. During the valley electricity period, the electric heating pipe 9 is used to heat the cold molten salt in the molten salt tank 8, and the heat is stored by the molten salt heat storage to heat the condensed water to generate the steam required in the production process. During the non-valley electricity period, the stored molten salt heat is used to heat the condensed water to supply steam.

[0028] The steam condensate recovery unit includes a steam condensate tank 7, the saturated water outlet of the flash tank 5 is connected to the steam condensate tank 7, the water inlet of the steam generator 11 is connected to the water outlet of the steam condensate tank 7, and the steam outlet of the steam generator 11 is connected to the steam supply pipe. The steam condensate tank 7 can not only be used for steam generation of the valley electric molten salt energy storage steam supply unit to improve the utilization rate of waste heat of steam condensate water, but also can be used as a cooling source of the high-temperature heat pump unit to cool the working medium in the condenser 4, and can also replenish and recover condensate water.

[0029] Specifically, in order to reduce the condensed water in the steam supplied by the Valley Electric molten salt energy storage steam supply unit, a vapor-liquid separation tank 12 is provided between the steam outlet of the steam generator 11 and the steam supply pipe, the inlet of the vapor-liquid separation tank 12 is connected to the steam outlet of the steam generator 11, the steam outlet of the vapor-liquid separation tank 12 is connected to the steam supply pipe, and the condensed water outlet of the vapor-liquid separation tank 12 is connected to the steam condensate tank 7.

[0030] Specifically, a first water pump 13 is provided on the connecting pipe between the steam condensate tank 7 and the steam generator 11 , and the condensed water entering the steam generator 11 is pressurized by the first water pump 13 .

[0031] Specifically, the steam condensate tank 7 is connected to the water inlet of the condenser 4, and the water outlet of the condenser 4 is connected to the condensate recovery pipeline. The low-temperature condensed water in the steam condensate tank 7 is used as a cooling source to cool the working medium in the condenser 4.

[0032] Specifically, a second water pump 14 is provided on the connecting pipe between the steam condensate tank 7 and the condenser 4 , and the condensed water entering the condenser 4 is pressurized by the second water pump 14 .

[0033] Specifically, a reflux pipe is provided on the upper part of the steam condensate tank 7, the reflux pipe is connected to the condensate recovery pipe, and a float valve is provided on the reflux pipe; through the reflux pipe with the float valve, excess condensate in the steam condensate tank 7 can automatically flow into the condensate recovery pipe.

[0034] In this embodiment, the condensate recovery pipeline and the condensate supply pipeline are both connected to an external condensate recovery tank, and the condensate recovery tank is used to recover the steam condensate recovered during the production process.

[0035] In this embodiment, there are three molten salt tanks 8, and the three molten salt tanks 8 are arranged in parallel, and valves are respectively arranged on the inlet and outlet of each molten salt tank 8.

[0036] The valley electricity molten salt energy storage coupled high-temperature heat pump steam supply system of the utility model uses the recovered steam condensate as the condensate source, uses the high-temperature heat pump unit to generate high-temperature water, flashes low-pressure steam through the flash tank 5, and then compresses it into the steam required in the production process through the steam compressor 61; uses the molten salt tank 8 to store heat through molten salt heat storage during the valley electricity period, and supplies steam at the same time, or uses the stored heat to supply steam during the non-valley electricity period; the high-temperature heat pump unit steam supply unit and the valley electricity molten salt energy storage steam supply unit form two parallel steam supply systems for complementary steam supply, thereby improving the stability of steam supply; the steam condensate generated by the high-temperature heat pump unit steam supply unit is stored in the steam condensate tank 7 for steam generation of the valley electricity molten salt energy storage steam supply unit, thereby improving the utilization rate of the waste heat of the steam condensate; the condensate in the steam condensate tank 7 enters the condensate recovery tank after passing through the condenser 4, and the condensate in the condensate recovery tank is used for the high-temperature heat pump unit steam supply unit and the valley electricity molten salt energy storage steam supply unit, thereby also improving the utilization rate of the waste heat of the steam condensate.

[0037] The above description is a preferred embodiment of the present invention, which is used to explain the technical solution of the present invention. Those skilled in the art can also make routine modifications, equivalent substitutions and improvements within the spirit and principles of the present invention.

Claims

1. A valley electric molten salt energy storage coupled with a high-temperature heat pump steam supply system, characterized in that: It includes a high-temperature heat pump unit steam supply unit, a valley electric molten salt energy storage steam supply unit, and a steam condensate recovery unit; The high-temperature heat pump unit steam supply unit includes a compressor, an evaporator, a throttle valve, a condenser, a flash tank, and a steam compressor. The compressor, the evaporator, the throttle valve, and the condenser form a high-temperature heat pump unit loop. There is a working medium in the loop. The water inlet of the evaporator is connected to the condensate supply pipeline, the water outlet of the evaporator is connected to the inlet of the flash tank, the steam outlet of the flash tank is connected to the inlet of the steam compressor, and the outlet of the steam compressor is connected to the steam supply pipe; The valley electric molten salt energy storage steam supply unit comprises a molten salt tank, a molten salt pump, and a steam generator. An electric heating pipe is arranged in the molten salt tank. The molten salt tank is connected to the molten salt pump and the steam generator in a loop in sequence. The steam condensate recovery unit comprises a steam condensate tank, the saturated water outlet of the flash tank is connected to the steam condensate tank, the water inlet of the steam generator is connected to the water outlet of the steam condensate tank, and the steam outlet of the steam generator is connected to the steam supply pipe.

2. The valley electric molten salt energy storage coupled high temperature heat pump steam supply system according to claim 1 is characterized in that: A vapor-liquid separation tank is provided between the steam outlet of the steam generator and the steam supply pipe, the inlet of the vapor-liquid separation tank is connected to the steam outlet of the steam generator, the steam outlet of the vapor-liquid separation tank is connected to the steam supply pipe, and the condensed water outlet of the vapor-liquid separation tank is connected to the steam condensate tank.

3. The valley electric molten salt energy storage coupled high temperature heat pump steam supply system according to claim 2 is characterized in that: A first water pump is provided on the connecting pipeline between the steam condensate tank and the steam generator.

4. The valley electric molten salt energy storage coupled high temperature heat pump steam supply system according to claim 3 is characterized in that: The steam condensate tank is connected to the water inlet of the condenser, and the water outlet of the condenser is connected to the condensate recovery pipeline.

5. The valley electric molten salt energy storage coupled high temperature heat pump steam supply system according to claim 4 is characterized in that: A second water pump is provided on the connecting pipeline between the steam condensate tank and the condenser.

6. The valley electric molten salt energy storage coupled high temperature heat pump steam supply system according to claim 5 is characterized in that: A reflux pipe is provided on the upper part of the steam condensate tank, the reflux pipe is connected to the condensate recovery pipeline, and a float valve is provided on the reflux pipe.

7. The valley electric molten salt energy storage coupled high temperature heat pump steam supply system according to claim 1 is characterized in that: There are multiple molten salt tanks, and the multiple molten salt tanks are arranged in parallel.

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