Efficient salt melting system suitable for heating and melting solid molten salt into liquid molten salt

Abstract

The invention discloses a high-efficiency salt melting system suitable for heating and melting solid molten salt into liquid molten salt, comprising a salt melting tank which is a container for heating and melting solid molten salt into liquid molten salt; the feeding holes are symmetrically formed in the top of the salt dissolving tank; the salt dissolving electric heaters are symmetrically arranged at the bottom of the salt dissolving tank and are used for heating the solid molten salt; the liquid collecting bag is concavely arranged on the bottom wall of the salt dissolving tank and is positioned between the salt dissolving electric heaters; the molten salt pump comprises a submerged pump and a molten salt motor; the fused salt heating electric heater is provided with an inlet and an outlet, and the inlet of the fused salt heating electric heater is connected with a salt outlet pipeline extending into the salt dissolving tank; and the outlet is connected with salt return ports on two sides of the salt dissolving tank. The system can effectively and uniformly melt solid molten salt, can reduce the residual amount of liquid molten salt as much as possible, and avoids waste; and secondly, an electric heating link in the molten salt heat storage system is fully utilized to heat solid molten salt in an initial salt dissolving process, so that the salt dissolving time is shortened, and the production process of the molten salt heat storage system is accelerated.

Description

Technical Field

[0001] The invention relates to the technical field of petrochemical industry, and in particular to an efficient salt-melting system suitable for heating and melting solid molten salt into liquid molten salt. Background Art

[0002] With the expansion of renewable energy power generation and the opening of the power market, new opportunities and challenges have been brought to the development of the power grid. One of the key issues is how to balance the supply and demand between the unstable output of renewable energy and the uncontrollable user electricity demand to ensure the stability and reliability of the power grid. Molten salt energy storage technology is an important means to solve the energy crisis. As a relatively mature thermal storage technology, it has broad application prospects.

[0003] The molten salt thermal storage system uses a molten salt electric heater to heat the molten salt and store energy in the form of heat. When heat is needed, the working fluid is heated through a heat exchanger to achieve the required purpose.

[0004] However, in the early stage of the molten salt thermal storage system, there is a key task that must be completed, which is to convert the solid molten salt into liquid molten salt by heating so that it can be continuously recycled in the molten salt thermal storage system. This process is called the salt-making process, and a salt-making system is required to complete this process. Summary of the invention

[0005] The purpose of the present invention is to provide a salt-forming system that can efficiently complete the task of heating solid molten salt and converting it into liquid molten salt in the early stage of the molten salt thermal storage system. At the same time, the salt-forming tank has a smaller structure size and a shorter salt-forming time, thereby saving time and economic costs.

[0006] To achieve the above-mentioned purpose, the technical solution of the present application is: an efficient salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, comprising:

[0007] The salt tank is a container for heating and melting solid molten salt into liquid molten salt;

[0008] The feed inlet is symmetrically arranged on the top of the salt tank;

[0009] The molten salt electric heater is symmetrically arranged at the bottom of the molten salt tank to heat the solid molten salt;

[0010] The liquid collecting bag is recessed on the bottom wall of the salt tank and located between the salt electric heaters;

[0011] A molten salt pump, comprising a submersible pump and a molten salt motor, wherein the submersible pump is located in a liquid collecting bag, and the molten salt motor is located at a salt outlet of a salt tank;

[0012] The molten salt heating electric heater has an inlet and an outlet. The inlet is connected to the salt outlet pipeline extending into the salt tank to heat the output liquid molten salt again; the outlet is connected to the salt return ports on both sides of the salt tank to transport the heated liquid molten salt back to the salt tank.

[0013] Furthermore, the molten salt electric heater, molten salt pump, and molten salt heating electric heater are all connected to the control cabinet.

[0014] Furthermore, two molten salt heating electric heaters are arranged up and down, the upper molten salt heating electric heater is connected to the low-temperature molten salt storage tank, and the lower molten salt heating electric heater is connected to the salt return ports on both sides of the salt tank through valves.

[0015] Furthermore, the inner bottom surface of the liquid collection bag is an arc-shaped concave surface.

[0016] Furthermore, the liquid collecting bag is located in the middle of the salt tank, and a salt discharge port is provided at the bottom of the liquid collecting bag.

[0017] Furthermore, the molten salt heating electric heaters arranged up and down are connected in series.

[0018] Furthermore, the bottom end of the salt outlet pipeline extends into the liquid collecting bag, and a valve is provided on the salt outlet pipeline outside the salt tank.

[0019] Furthermore, the salt tank is provided with a radar level meter connected to the control cabinet.

[0020] As a further step, the salt tank is provided with a thermocouple connected to the salt electric heater, and the thermocouple is connected to the control cabinet.

[0021] As a further step, a salt tank saddle is provided at the bottom of the salt tank, wherein the salt tank saddle located on one side adopts a roller design.

[0022] By adopting the above technical scheme, the present invention can achieve the following technical effects: the system can effectively and evenly melt the solid molten salt, and can also minimize the residual amount of liquid molten salt to avoid waste; secondly, the electric heating link in the molten salt thermal storage system is fully utilized to heat the solid molten salt in the initial salt-making process, thereby reducing the salt-making time and accelerating the commissioning process of the molten salt thermal storage system.

[0023] After the implementation of this system, the salt-making speed can be kept constant while saving no less than 30% of the production cost of the salt-making tank. When the size of the salt-making tank remains unchanged, the salt-making speed can be increased by more than 1 times, which can save the operating time and investment cost in the initial stage of production and improve the working efficiency of the molten salt thermal storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1It is a schematic diagram of the structure of an efficient salt-melting system suitable for heating and melting solid molten salt into liquid molten salt;

[0025] Explanation of serial numbers in the figure: 100. Salt tank; 110. Salt tank saddle; 120. Salt electric heater; 130. Salt return port; 140. Feed port; 150. Thermocouple; 160. Radar level gauge; 170. Salt discharge port; 180. Liquid collecting bag; 200. Molten salt pump; 210. Salt outlet; 300. Molten salt heating electric heater; 400. Control cabinet. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the specification of the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0028] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0029] It should be noted that, in this article, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that an article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0030] In the description of the present application, the terms "upper", "lower", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the products of the present application are usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0031] In the description of this application, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0032] like Figure 1 As shown, this embodiment provides an efficient salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, comprising:

[0033] The salt tank is a container for heating and melting solid molten salt into liquid molten salt;

[0034] The feed inlet is symmetrically arranged on the top of the salt tank;

[0035] The molten salt electric heater is symmetrically arranged at the bottom of the molten salt tank to heat the solid molten salt;

[0036] The liquid collecting bag is located in the middle of the salt tank, is recessed on the bottom wall of the salt tank and is located between the salt electric heaters;

[0037] A molten salt pump, comprising a submersible pump and a molten salt motor, wherein the submersible pump is located in a liquid collecting bag, and the molten salt motor is located at a salt outlet of a salt tank;

[0038] The molten salt heating electric heater has an inlet and an outlet, wherein the inlet is connected to the salt outlet pipeline extending into the salt tank, and is used to heat the output liquid molten salt again; the outlet is connected to the salt return ports on both sides of the salt tank, and is used to transport the liquid molten salt after the temperature is raised again back to the salt tank; two molten salt heating electric heaters are arranged in an upper and a lower position, wherein the upper molten salt heating electric heater is connected to the low-temperature molten salt storage tank, and the lower molten salt heating electric heater is connected to the salt return ports on both sides of the salt tank through valves;

[0039] The molten salt electric heater, molten salt pump and molten salt heating electric heater are all connected to the control cabinet.

[0040] The working method of the above-mentioned efficient salt-melting system suitable for heating and melting solid molten salt into liquid molten salt is as follows: the solid molten salt is conveyed to the feed port 140 by a conveyor belt, and then enters the salt-melting tank 100, and the salt-melting electric heater 120 is started to heat and melt the solid molten salt into liquid molten salt. When it is detected that the temperature of the molten salt in the liquid collecting bag 180 reaches the set value, the molten salt pump 200 is started through the control cabinet 400, and the liquid molten salt is transported to the molten salt heating electric heater 300 through the molten salt pump salt outlet 210. After the molten salt heating electric heater 300 is heated again, part of the heated molten salt is injected into the salt-melting tank 100 through the salt return port 130 as needed to increase the speed of melting the solid molten salt into liquid molten salt, and the remaining heated molten salt is transported to the low-temperature molten salt storage tank.

[0041] As a preferred embodiment of the present invention, a liquid collecting bag 180 is arranged at the middle bottom of the tank body of the salt tank 100, and the inner bottom surface of the liquid collecting bag 180 is an arc-shaped concave surface. The liquid molten salt in the tank body will first gather to the liquid collecting bag, and the liquid level in the tank body will gradually rise after the liquid collecting bag is filled with liquid molten salt; and, since the starting end of the salt outlet pipeline is located in the liquid collecting bag, most or even all of the liquid molten salt can be sent out through the pipeline. Compared with the prior art in which a large amount of liquid molten salt is accumulated in the molten salt storage tank and cannot be discharged, the molten salt tank can reduce or even avoid the accumulation of liquid molten salt in the tank body, so that all the molten salt can be used. Even if part of the liquid molten salt is not used, it is easy to be discharged through the salt discharge port 170, which ultimately saves the cost of using molten salt. In addition, the salt tank saddle 110 designed this time adopts a roller design at one end, which can effectively release the thermal expansion of the salt tank body 100 caused by the increase in temperature.

[0042] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An efficient salt melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that include: The salt tank is a container for heating and melting solid molten salt into liquid molten salt; The feed inlet is symmetrically arranged on the top of the salt tank; The molten salt electric heater is symmetrically arranged at the bottom of the molten salt tank to heat the solid molten salt; The liquid collecting bag is recessed on the bottom wall of the salt tank and located between the salt electric heaters; A molten salt pump, comprising a submersible pump and a molten salt motor, wherein the submersible pump is located in a liquid collecting bag, and the molten salt motor is located at a salt outlet of a salt tank; The molten salt heating electric heater has an inlet and an outlet. The inlet is connected to the salt outlet pipeline extending into the salt tank to heat the output liquid molten salt again; the outlet is connected to the salt return ports on both sides of the salt tank to transport the heated liquid molten salt back to the salt tank.

2. According to claim 1, a high-efficiency salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that The molten salt electric heater, molten salt pump and molten salt heating electric heater are all connected to the control cabinet.

3. According to claim 1, a high-efficiency salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that The molten salt heating electric heaters are arranged in two upper and lower parts. The upper molten salt heating electric heater is connected to the low-temperature molten salt storage tank, and the lower molten salt heating electric heater is connected to the salt return ports on both sides of the salt tank through valves.

4. According to claim 1, a high-efficiency salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that The inner bottom surface of the liquid collection bag is an arc-shaped concave surface.

5. According to claim 1, a high-efficiency salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that The liquid collecting bag is located in the middle of the salt tank, and a salt discharge port is arranged at the bottom of the liquid collecting bag.

6. According to claim 3, a high-efficiency salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that The molten salt heating electric heaters arranged up and down are connected in series.

7. According to claim 1, a high-efficiency salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that The bottom end of the salt outlet pipeline extends into the liquid collecting bag, and a valve is arranged on the salt outlet pipeline outside the salt tank.

8. According to claim 1, a high-efficiency salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that The salt tank is provided with a radar level meter connected to the control cabinet.

9. According to claim 1, a high-efficiency salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that The salt tank is provided with a thermocouple connected to the salt electric heater, and the thermocouple is connected to the control cabinet.

10. According to claim 1, a high-efficiency salt-melting system suitable for heating and melting solid molten salt into liquid molten salt, It is characterized in that A salt tank saddle is arranged at the bottom of the salt tank, wherein the salt tank saddle located at one side adopts a roller design.

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