Water-fused salt cascade energy storage steam generation device and system

Abstract

The utility model provides a water-fused salt cascade energy storage steam generating device and system, a first input end of a high-temperature water storage tank is communicated with a water supply device, a second input end of the high-temperature water storage tank is communicated with a gas constant pressure device, and a water storage electric heater is arranged in the high-temperature water storage tank and is used for heating water in the high-temperature water storage tank under a high-pressure condition; the input end of the fused salt storage and heat exchange device is communicated with the output end of the high-temperature water storage tank through a pipeline and a valve body, a steam opening is formed in the output end of the fused salt storage and heat exchange device, and a fused salt electric heater is arranged in the fused salt storage and heat exchange device and used for heating fused salt in the fused salt storage and heat exchange device. According to the water-fused salt cascade energy storage steam generation device, the heating and energy storage functions of the water body and the fused salt are achieved respectively, the steam production efficiency is improved, and the electric energy cost in the steam production process is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of steam generators, and in particular relates to a water-molten salt cascade energy storage steam generating device and system. Background Art

[0002] In the field of heating process applications, small and medium-sized low-pressure steam demand is mainly produced by natural gas boilers or electric boilers. Since the price of natural gas supply fluctuates greatly due to changes in external conditions and it is not a green energy, the cost of use is relatively high for enterprises. The device that directly uses the steam generated by electric boilers needs to be produced in real time. The steam demand period is mostly during the peak period of electricity consumption. The long-term use of electric boilers leads to high electricity consumption of enterprises. In addition, with the development of technology, some companies have proposed a technical solution that can generate steam by exchanging heat with high-temperature molten salt in the storage tank. However, under the existing technology, at the end of the heat exchange process between water and high-temperature molten salt, the overall temperature of the molten salt decreases, the heat exchange efficiency decreases, resulting in unstable heat exchange power and insufficient heat release. If the amount of molten salt is simply increased or the heat storage capacity of the molten salt is increased, the cost is relatively high and the cost performance is low. At the same time, the molten salt needs to be heated for a long time during the steam demand period, and heat storage cannot be achieved, and the cost of electricity use is high. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a water-molten salt cascade energy storage steam generation system to solve the technical problems of poor heat exchange efficiency between water and molten salt and high power consumption in the existing steam generation system.

[0004] In order to solve the above problems, the technical solution of the utility model is: a water-molten salt cascade energy storage steam generating device, comprising: a high-temperature water storage tank, a first input end of the high-temperature water storage tank is connected to a water supply device through a first pipeline, and the first pipeline is provided with a first pump body for pumping water into the high-temperature water storage tank; a second input end of the high-temperature water storage tank is connected to a gas constant pressure device through a second pipeline, and the gas constant pressure device is used to output high-pressure gas to limit the gas pressure inside the high-temperature water storage tank to be greater than a standard atmospheric pressure; a water storage electric heater is provided inside the high-temperature water storage tank, and the water storage electric heater is used to limit the temperature of the water body in the high-temperature water storage tank, and cooperate with the pressure to maintain the water body in a high-temperature undersaturated state;

[0005] A molten salt heat storage and exchange device, wherein the input end of the molten salt heat storage and exchange device is connected to the output end of the high-temperature water storage tank through a third pipeline, and the third pipeline is provided with a valve body to control the water in the high-temperature water storage tank to flow into the molten salt heat storage and exchange device; a molten salt electric heater is provided inside the molten salt heat storage and exchange device, and the molten salt electric heater is used to limit the molten salt temperature in the molten salt heat storage and exchange device; a steam port is provided at the output end of the molten salt heat storage and exchange device, and a liquid spray device is provided laterally at the output end of the steam port, and the liquid spray device is used to limit the temperature and pressure of the steam output from the steam port by spraying low-temperature liquid mist;

[0006] The water storage electric heater and the molten salt electric heater are respectively configured to convert electrical energy into water and molten salt thermal energy in the high-temperature water storage tank and the molten salt storage and exchange device during off-peak power periods. During peak power periods, the high-temperature water storage tank and the molten salt storage and exchange device use the valve body to exchange heat between the water and the molten salt through the built-in pipeline of the molten salt tank to achieve steam production operations.

[0007] Preferably, the water supply device includes a water supply end and a water softening device, the water supply end is connected to the input end of the water softening device, the water softening device is used to soften the water input by the water supply end, and the output end of the water softening device is connected to the first input end of the high-temperature water storage tank through the first pipeline.

[0008] Preferably, the output end of the liquid spray device includes a nozzle, and the nozzle is provided with a plurality of spray holes on the side facing the steam flow path; the input end of the liquid spray device is connected to the output end of the water softening equipment through a fourth pipeline, and a second pump body is provided in the fourth pipeline for pumping water into the internal chamber of the liquid spray device.

[0009] Preferably, the high-temperature water storage tank and the shell of the molten salt storage and heat exchange device are made of thermal insulation material.

[0010] Preferably, a first temperature sensor is provided at the top, middle and bottom of the high-temperature water tank, and a pressure sensor is provided at the top of the high-temperature water tank; a second temperature sensor is provided at the top, middle and bottom of the molten salt heat storage and exchange device.

[0011] Preferably, a liquid level sensor is provided on the inner side wall of the high-temperature water storage tank, and the liquid level sensor is used to monitor the water capacity in the high-temperature water storage tank.

[0012] Preferably, the composition of the molten salt is a mixture of one or more of NaNO3, KNO3, NaCl, KCl, Na2CO3, and K2CO3.

[0013] Preferably, under rated operating conditions, the water temperature inside the high-temperature water storage tank ranges from 150 to 200°, and the gas pressure inside the high-temperature water storage tank ranges from 0.5 to 1.5 MPa.

[0014] Preferably, under rated operating conditions, the temperature range of the molten salt inside the molten salt heat storage and exchange device is 180-450°.

[0015] Based on the same concept, the utility model also provides a water-molten salt cascade energy storage steam generation system, including any one of the water-molten salt cascade energy storage steam generation devices described above.

[0016] Due to the adoption of the above technical solution, the utility model has the following advantages and positive effects compared with the prior art:

[0017] The utility model provides a water-molten salt cascade energy storage steam generation system. On the basis of the existing molten salt storage and heat exchange device, a high-temperature water storage tank is added, and the pressure in the high-temperature water storage tank is increased by a gas constant pressure device, so that the undersaturated water in the high-temperature water storage tank is at a higher temperature, and can be stored in the high-temperature water storage tank for a long time. When there is a demand for steam, high-temperature undersaturated water is supplied to the molten salt storage and heat exchange device for heat exchange to generate steam. By heating and heat-insulating the molten salt and the undersaturated water separately, the heat exchange cycle after the water and the molten salt are in contact is extended, the heat exchange efficiency is improved, and sufficient heat exchange is performed to generate a large amount of steam. At the same time, through the heat storage technology, the high-temperature water storage tank and the molten salt storage and heat exchange device can be heated in advance during the valley power period, and only the heat exchange process between water and molten salt is performed during the peak power period or the steam demand period, which greatly reduces the cost of electricity consumption while ensuring the steam output and quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic structural diagram of a water-molten salt cascade energy storage steam generating device provided by the utility model.

[0019] Explanation of the reference numerals: 1: high-temperature water storage tank; 2: molten salt storage and heat exchange device; 3: soft water equipment; 4: water supply end; 5: gas constant pressure device; 6: water storage electric heater; 7: molten salt electric heater; 8: pump body; 9: valve body; 10: steam port; 11: liquid spray device. DETAILED DESCRIPTION

[0020] The following is a further detailed description of a water-molten salt cascade energy storage steam generation device and system proposed by the utility model in combination with the accompanying drawings and specific embodiments. The advantages and features of the utility model will become clearer according to the following description and claims.

[0021] First embodiment

[0022] See also Figure 1In a water-molten salt cascade energy storage steam generating device provided in this embodiment, a molten salt storage and exchange device 2 and a high-temperature water storage tank 1 are provided. The interior of the molten salt storage and exchange device 2 is used to place molten salt, and the interior of the high-temperature water storage tank 1 is used to store water. An input end is provided at the top of the molten salt storage and exchange device 2. The input end of the molten salt storage and exchange device 2 is connected to the output end at the bottom of the high-temperature water storage tank 1 through a third pipeline, and the water in the high-temperature water storage tank 1 is controlled by a valve body 9 to be transmitted to the heat exchanger in the molten salt storage and exchange device 2 to perform steam production operations.

[0023] A molten salt electric heater 7 and a water storage electric heater 6 are respectively provided inside the molten salt heat storage and exchange device 2 and the high-temperature water storage tank 1, which are used to heat the molten salt and the water body. When the high-temperature molten salt and the high-temperature water body are indirectly contacted through the heat exchanger, the molten salt and the water body produce a heat exchange reaction, thereby generating a large amount of steam. The steam is transmitted to the steam port 10 through the output end of the molten salt heat storage and exchange device 2 to realize the subsequent steam collection and storage work. Among them, a first input end is provided on the top of the high-temperature water storage tank 1, which is connected to the water supply device through a first pipeline. A first pump body is provided in the first pipeline. The first pump body controls the water supply device to supply normal temperature water to the high-temperature water storage tank 1. A second input end is also provided on the top of the high-temperature water storage tank 1, which is connected to the gas constant pressure device 5 through a second management. The gas constant pressure device 5 inputs high-pressure gas into the high-temperature water storage tank 1 and maintains the pressure in the high-temperature water storage tank 1 greater than a standard atmospheric pressure. By increasing the pressure in the closed high-temperature water storage tank 1, the boiling point of the water in the high-temperature water storage tank 1 is increased when the water storage electric heater 6 is heated, and a higher water temperature can be maintained. In the subsequent heat exchange reaction with the molten salt in the molten salt storage and heat exchange device 2, it is easier to fully exchange heat to generate steam, thereby increasing the heat exchange reaction cycle and improving the steam generation efficiency.

[0024] The molten salt heat storage and exchange device 2 is provided with a liquid spraying device 11 on the side of the steam port 10 for outputting steam. In the early stage of the contact reaction between the high-temperature water body and the high-temperature molten salt, the generated steam will maintain a relatively high temperature and pressure. The liquid spraying device 11 can spray low-temperature liquid mist to the steam output from the steam port 10, thereby adjusting the temperature and pressure of the output steam. The temperature and pressure of the output steam can be maintained within the required range through the cooling and pressure reducing effect of the low-temperature liquid mist, thereby ensuring the output quality of the steam.

[0025] Preferably, the water supply device includes a water supply end 4 and a water softening device 3, and the water supply end 4 is connected to the output end of the water softening device 3 to supply ordinary water to the water softening device 3. The water softening device 3 uses ion exchange technology to adsorb and filter out calcium, magnesium and other ions in the water to reduce the hardness of the water. The output end of the water softening device 3 is connected to the first input end of the high-temperature water storage tank 1 through a first pipeline and a first pump body. The first pump body pumps the softened water in the water softening device 3 into the high-temperature water storage tank 1. After the softened water is heated by the water storage electric heater 6, the high-temperature water can remain in an undersaturated state and cannot form scale and sediment, which is beneficial to the long-term and stable operation of the steam generating device, reduces maintenance and cleaning work, and ensures the quality of the steam finally generated.

[0026] Furthermore, the output end of the liquid spray device 11 includes a nozzle, and a plurality of spray holes are provided on one side of the nozzle facing the output steam flow path. The input end of the liquid spray device 11 is connected to the output end of the water softening device 3 through a fourth pipeline. A second pump body is provided in the fourth pipeline for pumping the normal temperature water softened by the water softening device 3 into the internal chamber of the liquid spray device 11, and forming a low-temperature liquid mist through the nozzle. After the low-temperature liquid mist contacts the high-temperature and high-pressure output steam, the temperature and pressure of the output steam are reduced.

[0027] Preferably, the shells of the high-temperature water tank 1 and the molten salt storage and exchange device 2 are both made of thermal insulation materials. After the water in the high-temperature water tank 1 and the molten salt in the molten salt storage and exchange device 2 are heated to the set temperature by the water storage electric heater 6 and the molten salt electric heater 7 respectively, the water in the high-temperature water tank 1 and the molten salt storage and exchange device 2 can maintain a high temperature for a long time. The heating process of the water storage electric heater 6 and the molten salt electric heater 7 is the most power-consuming stage of the entire steam generating device. By designing the heat storage structure of the water and molten salt, heating and energy storage operations can be performed during valley power periods, and steam production can be carried out by relying on the heat-stored water and molten salt during peak power periods or steam demand periods, which greatly reduces the cost of electricity use by the steam generating device and can also reduce the establishment of transformer devices.

[0028] Furthermore, first temperature sensors are respectively provided at the top, middle and bottom of the high-temperature water storage tank 1. The first temperature sensors are used to monitor the temperature of water at various positions in the high-temperature water storage tank 1, and transmit the water temperature data to the control system in real time, so as to adjust the water storage electric heater 6 to accurately control the water temperature. Similarly, second temperature sensors are respectively provided at the top, middle and bottom of the molten salt storage and heat exchange device 2. The second temperature sensors are used to monitor the temperature of molten salt at various positions in the molten salt storage and heat exchange device 2, and transmit the molten salt temperature data to the control system in real time, so as to adjust the molten salt electric heater 7 to accurately control the molten salt temperature. In addition, a pressure sensor is provided at the top of the high-temperature water storage tank 1 to monitor the air pressure value inside the high-temperature water storage tank 1, and transmit the air pressure data to the control system in real time, so as to adjust the gas constant pressure device to accurately control the gas pressure in the high-temperature water storage tank 1, thereby ensuring that the water temperature in the high-temperature water storage tank 1 can be heated to the set range.

[0029] Furthermore, a liquid level sensor is also provided on the inner side wall of the high-temperature water tank 1. The liquid level sensor can monitor the water capacity in the high-temperature water tank 1 in real time, and transmit the water capacity data to the control system in real time. The water capacity in the high-temperature water tank 1 can be controlled by adjusting the opening and closing of the first pump body to prevent too little water or overfilling of the water body.

[0030] Preferably, the composition of the molten salt is a mixture of one or more of NaNO3, KNO3, NaCl, KCl, Na2CO3, and K2CO3.

[0031] Preferably, under rated operating conditions, the water temperature range inside the high-temperature water storage tank 1 is set to 150-200°, the gas pressure range inside the high-temperature water storage tank 1 is set to 0.5-1.5Mpa, and the molten salt temperature range inside the molten salt heat storage and exchange device 2 is set to 180-450°. By heating the water and the molten salt, the overall heat storage capacity is increased, and the steam generation efficiency during the heat exchange process between the two is improved.

[0032] By means of a water-molten salt cascade energy storage steam generating device provided in this embodiment, the separate cascade heating function of the molten salt heat storage and exchange device 2 and the high-temperature water storage tank 1 is realized, so that the overall heat storage capacity is improved. In the heat exchange process after the water body contacts the molten salt, the heat exchange reaction cycle is extended, the heat conversion is fully realized, and the efficiency of steam generation is improved. At the same time, through the insulation structure design of the molten salt heat storage and exchange device 2 and the high-temperature water storage tank 1, the heating operation of the water body and the molten salt and the steam production operation are staggered. In the peak power stage when the steam demand is large, the heat exchange reaction is realized by relying on the heat stored in itself. In the valley power stage when the steam demand is small, the water body and the molten salt are heated and stored, which greatly reduces the cost of using electricity for the steam generating device and the setting of transformer equipment, and further improves the production efficiency.

[0033] Second embodiment

[0034] Based on the same concept, the present embodiment provides a water-molten salt cascade energy storage steam generation system, comprising a water-molten salt cascade energy storage steam generation device as described in any one of the above. During the steam production control process, the water supply end 4 provides ordinary water to the soft water equipment 3. The ordinary water is softened by the soft water equipment 3 to form an undersaturated water body, and is pumped into the high-temperature water storage tank 1 under the action of the first pump body, wherein the liquid level sensor in the high-temperature water storage tank 1 detects the water capacity in the high-temperature water storage tank 1 in real time. After the water capacity is lower than the minimum set value, the central control system controls the first pump body to start supplying water to the high-temperature water storage tank 1. When the water capacity is replenished to the maximum set value, the central control system controls the first pump body to close and suspend supplying water to the high-temperature water storage tank 1. The first temperature sensor in the high-temperature water tank 1 monitors the water temperature in real time and uploads the water temperature data to the central control system. The central control system controls the water storage electric heater 6 to heat the water in the high-temperature water tank 1, and at the same time controls the gas constant pressure device to input high-pressure gas into the high-temperature water tank 1 to increase the pressure in the high-temperature water tank 1. A pressure sensor is provided to monitor the pressure data so that the pressure is maintained within a set range, thereby increasing the boiling point of the water and maintaining the water temperature within a relatively high temperature range. At the same time, the insulation function of the high-temperature water tank 1 is used to achieve a long-term insulation effect on the water.

[0035] Similarly, a second temperature sensor is provided in the molten salt heat storage and exchange device 2, which monitors the temperature of the molten salt in real time and uploads the molten salt temperature data to the central control system, which controls the molten salt electric heater 7 to heat the molten salt in the molten salt heat storage and exchange device 2, and achieves a long-term heat preservation effect on the molten salt through the heat preservation function of the molten salt heat storage and exchange device 2. The central control system controls the heating operation of the water storage electric heater 6 and the molten salt electric heater 7 to be set to be performed during the off-peak period to save the cost of electricity use.

[0036] When there is a demand for steam production, the central control system controls the valve body 9 in the third pipeline connecting the high-temperature water storage tank 1 and the molten salt storage and heat exchange device 2 to open. The valve body 9 transmits the high-temperature water in the high-temperature water storage tank 1 to the heat exchanger in the molten salt storage and heat exchange device 2. The high-temperature water and the high-temperature molten salt are indirectly contacted through the heat exchanger to produce a heat exchange reaction, generating a large amount of steam. The steam is transmitted to the steam port 10 through the output end of the molten salt storage and heat exchange device 2. According to the actual demand standard of steam quality, the central control system controls the second pump body to spray the softened water in the softening equipment 3 through the liquid spraying device 11. The low-temperature mist liquid contacts the high-temperature and high-pressure steam to reduce the steam temperature and pressure to the required range, and finally collects the steam for subsequent transmission operations.

[0037] A water-molten salt cascade energy storage steam generation system provided in this embodiment can achieve precise control of the production of steam by the heat exchange reaction between water and molten salt, and reduce the cost of electricity consumed in the steam production process through energy storage design. While ensuring the efficiency of steam production, efficient application of heat is achieved, further improving the cost performance of the steam production process, and having extremely high economic benefits and safety.

[0038] The above is a detailed description of the embodiments of the present invention in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A water-molten salt cascade energy storage steam generating device, characterized in that: include: A high-temperature water storage tank, wherein a first input end of the high-temperature water storage tank is connected to a water supply device through a first pipeline, and the first pipeline is provided with a first pump body for pumping water into the high-temperature water storage tank; a second input end of the high-temperature water storage tank is connected to a gas constant pressure device through a second pipeline, and the gas constant pressure device is used to output high-pressure gas to limit the gas pressure inside the high-temperature water storage tank to be greater than a standard atmospheric pressure; a water storage electric heater is provided inside the high-temperature water storage tank, and the water storage electric heater is used to limit the temperature of the water in the high-temperature water storage tank and cooperate with the pressure to maintain the water in a high-temperature undersaturated state; A molten salt heat storage and exchange device, wherein the input end of the molten salt heat storage and exchange device is connected to the output end of the high-temperature water storage tank through a third pipeline, and the third pipeline is provided with a valve body to control the water in the high-temperature water storage tank to flow into the molten salt heat storage and exchange device; a molten salt electric heater is provided inside the molten salt heat storage and exchange device, and the molten salt electric heater is used to limit the molten salt temperature in the molten salt heat storage and exchange device; a steam port is provided at the output end of the molten salt heat storage and exchange device, and a liquid spray device is provided laterally at the output end of the steam port, and the liquid spray device is used to limit the temperature and pressure of the steam output from the steam port by spraying low-temperature liquid mist; The water storage electric heater and the molten salt electric heater are respectively configured to convert electrical energy into water and molten salt thermal energy in the high-temperature water storage tank and the molten salt storage and exchange device during off-peak power periods. During peak power periods, the high-temperature water storage tank and the molten salt storage and exchange device use the valve body to exchange heat between the water and the molten salt through the built-in pipeline of the molten salt tank to achieve steam production operations.

2. A water-molten salt cascade energy storage steam generating device according to claim 1, characterized in that: The water supply device includes a water supply end and a water softening device. The water supply end is connected to the input end of the water softening device. The water softening device is used to soften the water input by the water supply end. The output end of the water softening device is connected to the first input end of the high-temperature water storage tank through the first pipeline.

3. A water-molten salt cascade energy storage steam generating device as claimed in claim 2, characterized in that: The output end of the liquid spray device includes a nozzle, and the nozzle is provided with a plurality of spray holes on the side facing the steam flow path; the input end of the liquid spray device is connected with the output end of the water softening equipment through a fourth pipeline, and a second pump body is provided in the fourth pipeline for pumping water into the internal chamber of the liquid spray device.

4. A water-molten salt cascade energy storage steam generating device according to claim 1, characterized in that: The high-temperature water storage tank and the shell of the molten salt storage and heat exchange device are made of thermal insulation material.

5. A water-molten salt cascade energy storage steam generating device according to claim 1, characterized in that: A first temperature sensor is respectively provided at the top, middle and bottom of the high-temperature water storage tank, and a pressure sensor is respectively provided at the top of the high-temperature water storage tank; a second temperature sensor is respectively provided at the top, middle and bottom of the molten salt heat storage and exchange device.

6. A water-molten salt cascade energy storage steam generating device according to claim 1, characterized in that: A liquid level sensor is provided on the inner side wall of the high-temperature water storage tank, and the liquid level sensor is used to monitor the water capacity in the high-temperature water storage tank.

7. A water-molten salt cascade energy storage steam generating device according to claim 1, characterized in that: Under rated operating conditions, the water temperature inside the high-temperature water storage tank ranges from 150 to 200°, and the gas pressure inside the high-temperature water storage tank ranges from 0.5 to 1.5 MPa.

8. The water-molten salt cascade energy storage steam generating device according to claim 1, characterized in that: Under rated operating conditions, the temperature range of the molten salt inside the molten salt heat storage and exchange device is 180-450°.

9. A water-molten salt cascade energy storage steam generation system, characterized in that: It comprises the water-molten salt cascade energy storage steam generating device as described in any one of claims 1 to 8.

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