A molten salt electric heating device that is easy to replace and a replacement method

Abstract

The present invention discloses a molten salt electric heating device and a replacement method that are easy to replace, belonging to the field of molten salt heat storage equipment, comprising: a plurality of electric heating tubes, the plurality of electric heating tubes extending into a molten salt storage tank; a connecting device, connecting the plurality of electric heating tubes to the molten salt storage tank; a hollow tube body, the hollow tube body being arranged between the plurality of electric heating tubes and connected to the above-mentioned connecting device, the hollow tube body being a closed structure at one end close to the heat storage medium; an electric heating rod, the electric heating rod being detachably placed in the hollow tube body. The beneficial effect of the technical solution of the present invention is that: a hollow tube body is added to the heating tube body, and the length of the hollow tube body is greater than the length of the heating tube body. When the heating tube body is damaged and the heat storage medium solidifies, the electric heating rod is placed in the hollow tube body to heat the heat storage medium around the heating tube body, thereby melting the solidified heat storage medium, and the heating tube body can be removed and replaced.

Description

Technical Field

[0001] The present invention relates to the field of molten salt heat storage equipment, and in particular to a molten salt electric heating device that is easy to replace and a replacement method. Background Art

[0002] As the country vigorously promotes energy conservation and environmental protection and prohibits the use of small coal-fired boilers, most regions have begun to implement coal-to-electricity projects, using electricity instead of coal for heating. Molten salt heat storage technology has also gradually begun to develop. Molten salt heat storage technology heats the heat storage medium (such as molten salt) in the molten salt storage tank during off-peak periods or using cheap electricity, and stores the heat in the heat storage medium. When needed, the heat exchange medium is passed into the molten salt storage tank to exchange heat with the heat storage medium to obtain the required heat and supply it to the user. Since the heating efficiency is best when the electric heating device is in direct contact with the heat storage medium, and since the volume of the heat storage medium increases when it melts into a liquid, the electric heating device is inserted into the heat storage medium from the top of the molten salt storage tank so that when the molten salt is completely solidified, the electric heating device can be restarted without damaging the molten salt storage tank.

[0003] At present, the electric heating device in the molten salt heat storage equipment is a device that is easily damaged. When the heat storage equipment is shut down due to damage to the electric heating device, it takes a certain amount of time to make a new electric heating device. At this time, the molten salt in the molten salt storage tank may solidify, causing the electric heating device to be trapped in the solidified molten salt and unable to be pulled out, making it impossible to replace and repair the electric heating device. Therefore, in response to the above problems, it is urgent to design a molten salt electric heating device and replacement method that can be easily replaced to meet the needs of actual use. Summary of the Invention

[0004] In view of the above problems existing in the prior art, a molten salt electric heating device and a replacement method that are easy to replace are provided. The specific technical solution is as follows:

[0005] A molten salt electric heating device that is easy to replace, comprising:

[0006] A plurality of electric heating tubes, wherein the plurality of electric heating tubes extend into a molten salt storage tank, and the molten salt storage tank is used to store a heat storage medium;

[0007] A connecting device, connecting the plurality of electric heating pipes to the molten salt storage tank;

[0008] A hollow tube body, the hollow tube body being arranged between the plurality of electric heating tubes and connected to the connecting device, the end of the hollow tube body close to the heat storage medium being in a closed structure;

[0009] An electric heating rod is detachably placed in the hollow tube.

[0010] Preferably, the connecting device comprises:

[0011] A junction box, wherein the junction box is connected to the plurality of electric heating tubes, and the leads of the plurality of electric heating tubes are all arranged in the junction box and connected to a power supply;

[0012] The junction box is further provided with a circular hole which passes through the junction box from top to bottom, and the end of the hollow tube body away from the heat storage medium passes through the circular hole.

[0013] Preferably, the hollow tube body is arranged at the center position of the plurality of electric heating tubes.

[0014] Preferably, the connecting device further comprises a connecting flange, and the plurality of electric heating tubes are fixedly mounted on the molten salt storage tank via the connecting flange.

[0015] Preferably, the length of the hollow tube body is greater than the length of the electric heating tube, and one end of the hollow tube body close to the heat storage medium protrudes from each of the electric heating tubes.

[0016] Preferably, the length of the portion of the hollow tube protruding from the electric heating tube is 0.5-2 times the inner diameter of the electric heating tube.

[0017] Preferably, the diameter of the electric heating rod is smaller than the inner diameter of the hollow tube.

[0018] Preferably, each of the electric heating tubes has a non-heating area from the connecting flange downward to a preset range.

[0019] Preferably, the electric heating rod is a single-head electric heating rod.

[0020] The present invention also provides a method for replacing a molten salt electric heating device, including the molten salt electric heating device that is easy to replace as described above; comprising the following steps:

[0021] Step S1, inserting the electric heating rod into the hollow tube;

[0022] Step S2, turning on the power of the electric heating rod, so that the electric heating rod heats the heat storage medium;

[0023] Step S3, when the solidified heat storage medium around each of the electric heating tubes has melted, the connecting flange is opened and the entire electric heating device is taken out;

[0024] Step S4: Replace the electric heating device with a new one, and fix the new electric heating device to the molten salt storage tank through the connecting flange.

[0025] The beneficial effects of the technical solution of the present invention are:

[0026] The present invention improves on the original heating tube body by adding a hollow tube body to the heating tube body. When the heating tube body is damaged, causing the heat storage tank to shut down, and the heat storage medium solidifies, the electric heating device is used to place the electric heating rod into the hollow tube body to heat the heat storage medium around the heating tube body, thereby melting the solidified heat storage medium and removing the heating tube body for replacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic structural diagram of an easily replaceable electric heating device in the present invention;

[0028] Figure 2 It is a structural schematic diagram of a specific embodiment of the electric heating rod in the present invention;

[0029] Figure 3 It is a top view of a specific embodiment of the junction box in the present invention. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0031] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0033] The present invention provides an electric heating device that is easy to replace, which belongs to the field of molten salt heat storage equipment. Figure 1 and Figure 2 Shown, including:

[0034] A molten salt electric heating device that is easy to replace, comprising:

[0035] Multiple electric heating tubes 2, multiple electric heating tubes 2 extend into a molten salt storage tank (not shown in the figure), and the molten salt storage tank is used to store heat storage medium;

[0036] A connecting device, connecting the plurality of electric heating pipes 2 to the molten salt storage tank;

[0037] The hollow tube body 4 is arranged between the multiple electric heating tubes 2 and connected to the connecting device, and the end of the hollow tube body 4 close to the heat storage medium is a closed structure;

[0038] The electric heating rod 5 is detachably placed in the hollow tube 4 .

[0039] Specifically, in the present embodiment, the molten salt electric heating device includes an electric heating tube 2, a hollow tube body 4 and an electric heating rod 5; wherein the electric heating tube 2 adopts any electric heating tube that can be used in the molten salt heat storage equipment in the prior art; the present invention is based on the existing electric heating tube 2, and adds a hollow tube body 4 at its center position. The shape of the hollow tube body 4 can be designed according to actual conditions, for example, its cross section is set to a geometric structure such as a square, a diamond, or a triangle. Preferably, in the present embodiment, the hollow tube body 4 is cylindrical, and the lower end of the hollow tube body 4 is closed to avoid in the daily molten salt heat storage process, The heat storage medium enters the hollow tube body 4. If the lower end of the hollow tube body 4 does not adopt a closed structure, when the heat storage medium solidifies, solidified heat storage medium will also exist inside the hollow tube body 4. With the molten salt electric heating device of the present technical solution, when the electric heating tube 2 in the molten salt heat storage equipment is damaged, the electric heating rod 5 is inserted into the hollow tube body 4 and powered on for heating. Since the hollow tube body 4 is arranged at the center of the electric heating tube 2, the electric heating rod 5 can melt the solidified heat storage medium around the electric heating tube 2 with itself as the center, without having to melt all the heat storage medium in the molten salt storage tank, thereby saving more energy.

[0040] The advantages of the electric heating device provided by the present invention are that multiple electric heating tubes 2 and the hollow tube body are integrated into one, and it and the electric heating rod 5 adopt a detachable design. The electric heating rod 5 can be stored in the hollow tube body 4 on a daily basis, and can also be placed in the hollow tube body 4 when needed, and one electric heating rod 5 can be suitable for the electric heating tubes 2 in multiple molten salt heat storage devices.

[0041] In a preferred embodiment, the connecting device comprises:

[0042] A junction box 1 is connected to a plurality of electric heating tubes 2. Lead wires of the plurality of electric heating tubes 2 are all arranged in the junction box 1 and connected to a power supply;

[0043] The junction box 1 is further provided with a circular hole 11 which passes through the junction box 1 from top to bottom, and the end of the hollow tube 4 away from the heat storage medium passes through the circular hole 11 .

[0044] Specifically, the junction box 1 includes a box body and an upper box cover, and the circular hole 11 on the junction box 1 passes through from top to bottom; the electric heating tube 2 is fixed to the bottom of the box body of the junction box 1, and the hollow tube body 4 passes through the circular hole 11 at the bottom of the box body and is connected to the upper surface of the upper box cover. The lead of the electric heating tube 2 is set in the junction box 1 and is connected to the power supply of the installed molten salt heat storage equipment to provide electricity for the electric heating tube 2.

[0045] In a preferred embodiment, the connecting device further includes a connecting flange 3 , and the plurality of electric heating tubes 2 are fixedly mounted on the molten salt storage tank via the connecting flange 3 .

[0046] In a preferred embodiment, the length of the hollow tube 4 is greater than that of the electric heating tube 2 , and one end of the hollow tube 4 close to the heat storage medium protrudes from each electric heating tube 2 .

[0047] Specifically, in this embodiment, the length of the hollow tube body 4 is greater than the length of the electric heating tube 2, and the lower end of the hollow tube body 4 (i.e., the end close to the heat storage medium) is longer than the electric heating tube 2. This is because as the temperature rises, the density of the heat storage medium (molten salt) will decrease, so the heated heat storage medium will flow upward. If the lower end of the hollow tube body 4 is flush with the lower end of the electric heating tube 2, it is difficult to ensure that the heat storage medium around the bottom of the electric heating tube 2 can melt.

[0048] In a preferred embodiment, the length of the portion of the hollow tube 4 protruding from the electric heating tube 2 is 0.5-2 times the inner diameter of the electric heating tube 2 .

[0049] In a preferred embodiment, the diameter of the electric heating rod 5 is smaller than the inner diameter of the hollow tube 4, so that the electric heating rod 5 can be easily inserted into the hollow tube 4. Preferably, the diameter of the electric heating rod 5 is 1-2 mm smaller than the inner diameter of the hollow tube 4. The length of the electric heating rod 5 is at least greater than the length of the heating zone of the electric heating tube 2, and can be the same as the length of the hollow tube 4, so that it can just be inserted into the bottom of the hollow tube 4.

[0050] In a preferred embodiment, each electric heating tube 2 has a non-heating area from the connecting flange 3 downward to a preset range.

[0051] Specifically, the electric heating tube 2 is inserted from the top of the molten salt storage tank, and the electric heating tube 2 is fixedly installed on the molten salt storage tank through the connecting flange 3, and the lower end of the electric heating tube 2 is immersed in the heat storage medium. The area from below the connecting flange 3 to the electric heating tube 2 that is not immersed in the heat storage medium is a non-heating area to prevent it from dry burning in the air and causing damage to the electric heating tube 2.

[0052] In a preferred embodiment, the electric heating rod 5 is a single-head electric heating rod.

[0053] The present invention also provides a method for replacing a molten salt electric heating device, including the molten salt electric heating device that is easy to replace as described above; the steps for replacing the molten salt electric heating device are as follows:

[0054] Step S1, inserting the electric heating rod 5 into the hollow tube 4;

[0055] Step S2, turning on the power of the electric heating rod 5, so that the electric heating rod 5 heats the heat storage medium;

[0056] Step S3: After the solidified heat storage medium around each electric heating tube 2 has melted, the connecting flange 3 is opened and the entire electric heating device is taken out;

[0057] Step S4: Replace the electric heating device with a new one, and fix the new electric heating device to the molten salt storage tank via the connecting flange 3.

[0058] Specifically, when the electric heating tube 2 is damaged and waiting to be replaced, since the production of a new electric heating device takes a certain amount of time, at this time, the temperature of the heat storage medium drops and it will condense into a solid, and the electric heating tube 2 is frozen in the heat storage medium. Using the electric heating device provided by the present invention, the single-head electric heating rod 5 is inserted into the hollow tube body 4, and the power of the single-head electric heating rod 5 is turned on to heat the solidified heat storage medium. After waiting for a period of time, the electric heating rod 5 will melt the heat storage medium around the electric heating tube 2, and then open the connecting flange 3, pull out the electric heating tube 2, and then install the new electric heating device in the molten salt storage tank through the connecting flange 3 to realize the replacement of the electric heating tube 2 on the molten salt heat storage equipment.

[0059] The beneficial effects of the technical solution of the present invention are:

[0060] The present invention improves on the original heating tube body by adding a hollow tube body to the heating tube body, and the length of the hollow tube body is greater than the length of the heating tube body. When the heating tube body is damaged and the heat storage tank body stops, and the heat storage medium solidifies, the electric heating device is used to place the electric heating rod into the hollow tube body to heat the heat storage medium around the heating tube body, thereby melting the solidified heat storage medium and removing the heating tube body for replacement.

[0061] The above description is only a preferred embodiment of the present invention and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A molten salt electric heating device that is easy to replace, characterized in that: include: A plurality of electric heating tubes, wherein the plurality of electric heating tubes extend into a molten salt storage tank, and the molten salt storage tank is used to store a heat storage medium; A connecting device, connecting the plurality of electric heating pipes to the molten salt storage tank; A hollow tube body, the hollow tube body being arranged between the plurality of electric heating tubes and connected to the connecting device, the end of the hollow tube body close to the heat storage medium being in a closed structure; An electric heating rod is detachably placed in the hollow tube.

2. The molten salt electric heating device according to claim 1, characterized in that: The connecting device comprises: a junction box, the junction box being connected to the plurality of the electric heating tubes, wherein the leads of the plurality of the electric heating tubes are all arranged in the junction box and connected to a power supply; The junction box is further provided with a circular hole which passes through the junction box from top to bottom, and the end of the hollow tube body away from the heat storage medium passes through the circular hole.

3. The molten salt electric heating device according to claim 1, characterized in that: The hollow tube body is arranged at the center position of the plurality of electric heating tubes.

4. The molten salt electric heating device according to claim 1, characterized in that: The connecting device further comprises a connecting flange, and the plurality of electric heating tubes are fixedly mounted on the molten salt storage tank via the connecting flange.

5. The molten salt electric heating device according to claim 1, characterized in that: The length of the hollow tube body is greater than that of the electric heating tube, and one end of the hollow tube body close to the heat storage medium protrudes from each of the electric heating tubes.

6. The molten salt electric heating device according to claim 1, characterized in that: The length of the portion of the hollow tube protruding from the electric heating tube is 0.5-2 times the inner diameter of the electric heating tube.

7. The molten salt electric heating device according to claim 1, characterized in that: The diameter of the electric heating rod is smaller than the inner diameter of the hollow tube.

8. The molten salt electric heating device according to claim 4, characterized in that: Each of the electric heating tubes has a non-heating area from the connecting flange downward to a preset range.

9. The molten salt electric heating device according to claim 1, characterized in that: The electric heating rod is a single-head electric heating rod.

10. A method for replacing a molten salt electric heating device, characterized in that: The molten salt electric heating device according to any one of claims 1 to 9 comprises the following steps: Step S1, inserting the electric heating rod into the hollow tube; Step S2, turning on the power of the electric heating rod, so that the electric heating rod heats the heat storage medium; Step S3, when the solidified heat storage medium around each of the electric heating tubes has melted, the connecting device is opened and the entire electric heating device is taken out; Step S4: Replace the electric heating device with a new one, and fix the new electric heating device to the molten salt storage tank via a connecting flange.

Images