Efficient fused salt heat storage system and using method thereof

Abstract

The invention relates to an efficient fused salt heat storage system and a using method thereof, fluid can be efficiently heated, the efficient fused salt heat storage system comprises a fused salt tank, an annular upper water tank and an annular lower water tank, an auxiliary heating wire is arranged in the annular lower water tank, and the upper end and the lower end of the fused salt tank communicate with a fused salt inlet pipe and a fused salt outlet pipe correspondingly; the annular upper water tank and the annular lower water tank are communicated with a water inlet pipe and a water outlet pipe respectively, the molten salt tank further comprises a plurality of heating pipes arranged in the circumferential direction of the molten salt tank, the upper ends and the lower ends of the heating pipes are rotationally communicated with the annular upper water tank and the annular lower water tank respectively, and heat insulation layers and heat conduction layers are attached to the two sides of the heating pipes respectively. The heating pipe is attached to the interior of the containing groove in the outer side of the molten salt tank, heat preservation is conducted on the molten salt tank, meanwhile, heat emitted by the molten salt tank is transmitted to water in the heating pipe through the heat conduction layer, heating of the water is achieved, and the temperature of the water in the heating pipe is adjusted by rotating the heating pipe to adjust the size of the attaching face of the heat conduction layer and the containing groove. And an auxiliary heating wire in the annular lower water tank can be used for heating.

Description

Technical Field

[0001] The present invention relates to the field of fluid heating technology, and in particular to a high-efficiency molten salt heat storage system and a method for using the same. Background Art

[0002] The molten salt heat storage system heats cold salt into liquid hot salt and stores it in a hot salt tank. The hot salt in the hot salt tank is transported to the heat exchange system through a hot molten salt pump to exchange heat with water or water vapor. The liquid cold salt after releasing heat returns to the cold salt tank, completing the salt absorption, storage, and conversion cycle.

[0003] High-temperature molten salt can reach more than 500 degrees Celsius. As mentioned above, the heat in the high-temperature molten salt is used to heat the fluid, which can be the water used by the steam turbine generator. By heating the water, superheated steam is generated to drive the steam turbine generator to rotate and generate electricity. The fluid can also be boiler water, which is heated in the boiler and used for production and life.

[0004] However, when heating boiler water, the existing technology uses direct heat exchange through a heat exchanger. Since the temperature of liquid molten salt can reach more than 500 degrees Celsius, the water in contact with the liquid molten salt pipe wall will vaporize in large quantities during heat exchange, generating a large amount of steam. In order to prevent excessive pressure, these steams must be released, which will waste a lot of heat, and the temperature of the molten salt cannot be lowered. If it is too low, the molten salt will condense into a solid and block the pipeline. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a high-efficiency molten salt heat storage system and a method for using the same.

[0006] The present invention is achieved through the following technical scheme, and provides a high-efficiency molten salt heat storage system, including a molten salt tank, an annular upper water tank located above the molten salt tank, and an annular lower water tank located below the molten salt tank, an auxiliary electric heating wire is installed in the annular lower water tank, the upper and lower ends of the molten salt tank are respectively connected to a molten salt inlet pipe and a molten salt outlet pipe, the annular upper water tank and the annular lower water tank are respectively connected to the water inlet pipe and the water outlet pipe, and also includes a plurality of heating pipes arranged along the circumference of the molten salt tank, the upper and lower ends of the heating pipes are respectively rotated to connect the annular upper water tank and the annular lower water tank, the two sides of the heating pipes are respectively bonded with a heat insulation layer and a heat conductive layer, the outer side of the molten salt tank is provided with a receiving groove for accommodating the heating pipe, and the water temperature in the heating pipe is adjusted by rotating the heating pipe to adjust the size of the bonding surface between the heat conductive layer and the receiving groove.

[0007] As an optimization, the lower end surface of the annular upper water tank is equipped with an upper slewing bearing, and the upper end surface of the annular lower water tank is equipped with a lower slewing bearing. The upper and lower ends of the heating tube are respectively fixed with an upper connecting gear and a lower connecting gear. The upper connecting gear is meshed with the rotating circle of the upper slewing bearing, and the lower connecting gear is meshed with the rotating circle of the lower slewing bearing. A driving motor for driving the rotating circle of the upper slewing bearing to rotate is installed on the annular upper water tank.

[0008] As an optimization, it also includes an outer insulation cover that wraps the molten salt tank, the heating pipe is located in the outer insulation cover, and an insulation filling layer is provided in the outer insulation cover.

[0009] As an optimization, the upper end of the heating tube is provided with an upper convex edge located in the annular upper water tank, and a sealing gasket is installed between the upper convex edge and the inner wall of the annular upper water tank; the lower end of the heating tube is provided with a lower convex edge located in the annular lower water tank, and a sealing gasket is installed between the lower convex edge and the inner wall of the annular lower water tank, and the weight of the annular lower water tank is used to achieve compression and sealing at both ends of the heating tube.

[0010] As an optimization, the lower end of the annular lower water tank is equipped with a plurality of circumferentially arranged elastic support mechanisms, the elastic support mechanisms include a base fixed to the ground, an upper support seat fixedly connected to the lower end surface of the annular lower water tank, and a lower support seat located below the upper support seat, a spring is installed between the lower support seat and the upper support seat, a screw rod passing through the lower support seat is fixedly connected to the base, and the height of the lower support seat is adjusted by adjusting the position of the adjusting nut on the screw rod, thereby adjusting the supporting force applied by the spring to the annular lower water tank.

[0011] As an optimization, the water inlet pipe passes through the condensation tank, one end of the condensation tank is connected to the annular upper water tank through a steam exhaust pipe, and the other end of the condensation tank is provided with an upward exhaust port and a downward drain port.

[0012] As an optimization, it also includes a pressing mechanism that presses the middle part of all the heating tubes into the accommodating groove, and the pressing mechanism is released when the heating tubes rotate.

[0013] As an optimization, the clamping mechanism includes a fixed ring fixed to the outside of the molten salt tank, a floating ring sleeved on the outer ring of the fixed ring, and a cylinder driving the floating ring to move up and down. A pressure plate is provided between the heating tube and the fixed ring, and a push rod passing through the outer ring of the fixed ring is fixed to the pressure plate. The inner ring of the floating ring is provided with a clamping slope.

[0014] As an optimization, a circulation pipe is connected between the molten salt inlet pipe and the molten salt outlet pipe, and a circulation pump is installed on the circulation pipe.

[0015] A method for using a high-efficiency molten salt heat storage system comprises the following steps: a. High-temperature liquid molten salt enters the molten salt tank through the molten salt inlet pipe to achieve heat storage; b. Water enters the annular upper water tank through the water inlet pipe, flows to the annular lower water tank through multiple heating pipes, and finally flows out through the water outlet pipe; c. The heating pipe is attached to the containing tank outside the molten salt tank to keep the molten salt tank warm. At the same time, the heat emitted by the molten salt tank is transferred to the water in the heating pipe through the heat-conducting layer to heat the water. The water temperature in the heating pipe is adjusted by rotating the heating pipe to adjust the size of the fitting surface between the heat-conducting layer and the containing tank; d. When the contact area between the heat-conducting layer and the containing tank is at the maximum state and the water temperature does not meet the requirement, heating is performed through the auxiliary heating wire in the annular lower water tank.

[0016] The beneficial effects of the present invention are as follows: an efficient molten salt heat storage system and a method of using the same, water enters an annular upper water tank through a water inlet pipe, flows to an annular lower water tank through a plurality of heating pipes, and finally flows out through a water outlet pipe, the heating pipe is fitted in a containing tank outside a molten salt tank to insulate the molten salt tank, and at the same time, the heat emitted by the molten salt tank is transferred to the water in the heating pipe through a heat-conducting layer to heat the water, the water temperature in the heating pipe is adjusted by rotating the heating pipe to adjust the size of the fitting surface of the heat-conducting layer and the containing tank, and when the contact area between the heat-conducting layer and the containing tank is at a maximum state and the water temperature does not meet the requirements, the auxiliary heating wire in the annular lower water tank is used for heating, thereby heating the water.

[0017] The present invention heats water outside the molten salt tank. On the one hand, the heat transfer temperature is low, the high-temperature vaporization phenomenon of water is less, and the outer ring area of ​​the molten salt tank is large, which can realize the heating of large flow water. On the other hand, the thermal insulation function of the molten salt tank can be realized at the same time, thereby improving the thermal insulation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a structural schematic diagram of another angle of the present invention; Figure 3 It is a front view of the present invention; Figure 4 For the present invention Figure 3 AA surface section view; Figure 5 It is a schematic diagram of the structure of the molten salt tank of the present invention; Figure 6 It is a front view of the molten salt tank of the present invention; Figure 7 For the present invention Figure 6 CC section view; Figure 8 It is a front view of the heating tube of the present invention; Fig. 9 It is a schematic cross-sectional view of a heating tube of the present invention; Fig.10 For the present invention Figure 8 DD section view; Fig.11 It is a structural schematic diagram of the annular lower water tank and a single heating pipe of the present invention; Fig.12 It is a schematic diagram of the structure of the annular upper water tank and a single heating pipe of the present invention; Fig.13is a cross-sectional view of the elastic support mechanism of the present invention; Fig.14 It is a schematic diagram of the structure of the clamping mechanism of the present invention; Fig.15 For the present invention Figure 3 BB surface cross-sectional view; Fig.16 For the present invention Fig.15 EE cross-sectional view; As shown in the figure: 1. Annular upper water tank, 2. Molten salt tank, 3. Annular lower water tank, 4. Heating pipe, 41. Insulation layer, 42. Heat conducting layer, 43. Upper connecting gear, 44. Lower connecting gear, 45. Upper flange, 46. Lower flange, 47. Sealing pad, 5. Clamping mechanism, 51. Fixed ring, 52. Floating ring, 53. Pressing plate, 54. Push rod, 55. Cylinder, 6. Molten salt inlet pipe, 7. Molten salt outlet pipe, 8. Water inlet pipe, 9. Water outlet pipe, 10. Steam discharge pipe, 11, condensate tank, 12, exhaust port, 13, drain port, 14, support leg, 15, elastic support mechanism, 151, spring, 152, upper support seat, 153, lower support seat, 154, base, 155, screw, 156, adjusting nut, 16, circulation pipe, 17, lower slewing bearing, 18, upper slewing bearing, 19, driving gear, 20, driving motor, 21, outer insulation cover, 22, insulation filling layer. DETAILED DESCRIPTION

[0019] In order to clearly illustrate the technical features of this solution, this solution is described below through a specific implementation method.

[0020] like Figures 1 to 16 As shown, a high-efficiency molten salt heat storage system of the present invention includes a molten salt tank 2, an annular upper water tank 1 located above the molten salt tank 2, and an annular lower water tank 3 located below the molten salt tank 2.

[0021] The molten salt tank 2 is a vertical cylindrical tank body, which is airtightly arranged. The upper and lower ends of the molten salt tank 2 are respectively connected to the molten salt inlet pipe 6 and the molten salt outlet pipe 7. The high-temperature molten salt enters the molten salt tank 2 through the molten salt inlet pipe 6 for storage. When heating is required, the molten salt is discharged through the molten salt outlet pipe 7. The molten salt tank 2 is supported on the ground by four legs 14.

[0022] Since a heating pipe needs to be arranged outside the molten salt tank 2 in the present application, the molten salt inlet pipe 6 and the molten salt outlet pipe 7 can only be connected at the upper and lower end surfaces of the molten salt tank 2. The annular upper water tank 1 is annular, and the circular hole in the middle is convenient for the molten salt inlet pipe 6 to pass through. The annular lower water tank 3 is annular, and the circular hole in the middle is convenient for the molten salt outlet pipe 7 and the support leg 14 to pass through.

[0023] The annular upper water tank 1 and the annular lower water tank 3 are connected to the water inlet pipe 8 and the water outlet pipe 9 respectively. In this embodiment, the water inlet pipe 8 is horizontally connected to the side of the annular upper water tank 1, and the water outlet pipe 9 is horizontally connected to the side of the annular lower water tank 3.

[0024] It also includes a plurality of heating pipes 4 arranged circumferentially along the molten salt tank 2. The heating pipes 4 are vertical circular pipes. The upper and lower ends of the heating pipes 4 are respectively connected to the annular upper water tank 1 and the annular lower water tank 3 by rotation. The specific structure is shown in FIG. Fig.10 The upper end of the heating tube 4 penetrates into the lower end of the annular upper water tank 1 and an O-ring for sealing is installed in the penetration hole. The lower end of the heating tube 4 penetrates into the upper end of the annular lower water tank 3 and an O-ring for sealing is installed in the penetration hole.

[0025] The upper end of the heating tube 4 is provided with an upper flange 45 located in the annular upper water tank 1, and a sealing gasket 47 is installed between the upper flange 45 and the inner wall of the annular upper water tank 1. The lower end of the heating tube 4 is provided with a lower flange 46 located in the annular lower water tank 3, and a sealing gasket is installed between the lower flange 46 and the inner wall of the annular lower water tank 3. The annular lower water tank 3 in this embodiment is not provided with a fixed supporting structure, so its weight is supported by hanging the heating tube 4, so the weight of the annular lower water tank 3 is used to achieve compression and sealing at both ends of the heating tube 4.

[0026] Since the weight of the annular lower water tank 3 is too large, the sealing gasket 47 is easily over-pressed, which is not conducive to the rotation of the heating tube 4. Therefore, a plurality of circumferentially arranged elastic support mechanisms 15 are installed at the lower end of the annular lower water tank 3 to offset part of the weight.

[0027] The elastic support mechanism 15 includes a base 154 fixed to the ground, an upper support seat 152 fixedly connected to the lower end surface of the annular lower water tank 3, and a lower support seat 153 located below the upper support seat 152. A spring 151 is installed between the lower support seat 153 and the upper support seat 152. A screw rod 155 passing through the lower support seat 153 is fixedly connected to the base 154. The height of the lower support seat 153 is adjusted by adjusting the position of the adjusting nut 156 on the screw rod 155, thereby adjusting the supporting force applied by the spring 151 to the annular lower water tank 3.

[0028] like Fig. 9 As shown, the two sides of the heating tube 4 are respectively attached with a heat insulation layer 41 and a heat conduction layer 42, the heat insulation layer 41 plays a role of heat insulation, and the heat conduction layer 42 plays a role of heat conduction. The heat insulation layer 41 and the heat conduction layer 42 are both semicircular plates, and the outer circles of the heat insulation layer 41 and the heat conduction layer 42 form a cylindrical structure.

[0029] The molten salt tank 2 is provided with a receiving groove for receiving the heating tube 4 on the outside. The receiving groove is an arc-shaped groove with the same cross-section from top to bottom. The central angle of the arc is between 70 and 90 degrees, so as to wrap half or nearly half of the heating tube 4. Figure 5-7As shown, the containing grooves are densely arranged, so that most of the outer circle area of ​​the molten salt tank 2 is wrapped by the heating tube 4.

[0030] The water temperature in the heating tube 4 is adjusted by rotating the heating tube 4 to adjust the size of the contact surface between the heat conducting layer 42 and the receiving tank. When the receiving tank is entirely filled with the heat conducting layer 42, the heating effect on the heating tube is the best. When the receiving tank is entirely filled with the heat insulating layer 41, the heating effect on the heating tube is the worst and the heat preservation effect on the molten salt tank 2 is the best.

[0031] The outer heat-insulating cover 21 wraps the molten salt tank 2, and the heating pipe 4 is located in the outer heat-insulating cover 21. The outer heat-insulating cover 21 is provided with a heat-insulating filling layer 22 to prevent heat dissipation. For ease of observation, only the outer heat-insulating cover 21 is shown in the drawings of the present application. Figure 4 The heat-insulating cover 21 and the heat-insulating filling layer 22 are shown.

[0032] In order to realize the synchronous rotation of all the heating pipes, the lower end surface of the annular upper water tank 1 is equipped with an upper slewing bearing 18, and the upper end surface of the annular lower water tank 3 is equipped with a lower slewing bearing 17. All the heating pipes 4 are located in the inner circle of the upper slewing bearing 18 and the lower slewing bearing 17. The upper and lower ends of the heating pipes 4 are respectively fixed with an upper connecting gear 43 and a lower connecting gear 44. In order to facilitate the arrangement of the upper connecting gear 43 and the lower connecting gear 44, as shown in FIG. Figure 5 , 6 As shown, portions with reduced diameters are provided at the upper and lower ends of the molten salt tank 2 to avoid the upper connecting gear 43 and the lower connecting gear 44 .

[0033] The upper connecting gear 43 is meshed with the rotating circle of the upper slewing bearing 18, so that the rotating circle of the slewing bearing 18 rotates, driving all the upper connecting gears 43 to rotate, thereby driving all the heating pipes 4 to rotate, and the annular upper water tank 1 is equipped with a driving motor 20 for driving the rotating circle of the upper slewing bearing 18 to rotate. The driving motor 20 drives the driving gear 19 to rotate, and the outer ring of the rotating circle of the upper slewing bearing 18 is provided with external teeth, and the driving gear 19 meshes with the external teeth, thereby realizing the rotation of the rotating circle of the upper slewing bearing 18.

[0034] The lower connecting gear 44 meshes with the rotating circle of the lower slewing bearing 17, so that all the lower connecting gears 44 can rotate synchronously through the rotating circle of the lower slewing bearing 17, and the lower ends of all the heating tubes can rotate synchronously, preventing a single heating tube from being stuck and twisted.

[0035] Since the lower connecting gear 44 and the upper connecting gear 43 are both spur gears, the up and down floating of the annular lower water tank 3 is not affected.

[0036] As the heating tube is heated, the temperature of the molten salt at the inner edge of the molten salt tank 2 decreases. In order to improve the heating effect, a circulation pipe 16 is connected between the molten salt inlet pipe 6 and the molten salt outlet pipe 7. A circulation pump is installed on the circulation pipe 16. By turning on the circulation pump, the molten salt at the bottom of the molten salt tank 2 can be pumped into the top of the molten salt tank 2, so that the molten salt flows inside and the temperature at the edge is increased.

[0037] An auxiliary heating wire is installed in the annular lower water tank 3. When the contact area between the heat conductive layer and the containing groove is at the maximum state and the water temperature does not meet the requirement, heating is performed through the auxiliary heating wire in the annular lower water tank.

[0038] The present application inevitably generates steam during the heating process, and the present application sets a condenser 11, the water inlet pipe 8 passes through the condenser 11, one end of the condenser 11 is connected to the annular upper water tank 1 through the steam discharge pipe 10, and the other end of the condenser 11 is provided with an upward exhaust port 12 and a downward drain port 13. After the steam enters the condenser 11 and condenses, the gas is discharged through the exhaust port 12, and the condensed water is discharged through the drain port 13. During the condensation, the water in the water inlet pipe 8 is heated to improve the utilization rate of the heat.

[0039] Since the heating tube is long, the middle part is easy to bend and deform, so it cannot fit tightly with the receiving groove, and thus cannot achieve a good heat exchange effect. Therefore, the present application also includes a clamping mechanism 5 that presses the middle part of all the heating tubes 4 into the receiving groove, and the clamping mechanism 5 is released when the heating tube 4 rotates.

[0040] like Figure 14-16 The clamping mechanism 5 shown includes a fixed ring 51 fixedly connected to the outside of the molten salt tank 2, a floating ring 52 sleeved on the outer ring of the fixed ring 51, and a cylinder 55 for driving the floating ring 52 to move up and down. The fixed ring 51 is fixed on the outer wall of the molten salt tank 2 between adjacent heating tubes, and an arc-shaped avoidance groove is opened on the fixed ring 51 to avoid the heating tube.

[0041] A pressing plate 53 is provided between the heating tube 4 and the fixing ring 51 . Each heating tube 4 corresponds to a pressing plate 53 . The pressing plate 53 is an arc-shaped plate. A push rod 54 passing through the outer ring of the fixing ring 51 is fixedly connected to the pressing plate 53 . The end of the push rod 54 is spherical.

[0042] like Fig.16 As shown, the inner ring of the floating ring 52 described in the present application is provided with a pressing inclined surface. By moving the floating ring 52 downward, the push rod 54 is pressed inward, so that the pressing plate 53 presses the heating tube 4. Fig.14 As shown, two cylinders 55 are provided and are symmetrically arranged. The cylinders are fixed on the outside of the fixed ring 51 , and the cylinder telescopic shafts are connected to the floating ring 52 .

[0043] A method for using a high-efficiency molten salt heat storage system comprises the following steps: a. High-temperature liquid molten salt enters the molten salt tank 2 through the molten salt inlet pipe 6 to achieve heat storage; b. Water enters the annular upper water tank 1 through the water inlet pipe 8, flows to the annular lower water tank 3 through multiple heating pipes 4, and finally flows out through the water outlet pipe 9; c. The heating tube 4 is attached to the containing tank outside the molten salt tank 2 to keep the molten salt tank 2 warm. At the same time, the heat emitted by the molten salt tank 2 is transferred to the water in the heating tube 4 through the heat-conducting layer 42 to heat the water. The water temperature in the heating tube 4 is adjusted by rotating the heating tube 4 to adjust the size of the fitting surface between the heat-conducting layer 42 and the containing tank; d. When the contact area between the heat-conducting layer 42 and the containing groove is at the maximum state and the water temperature does not reach the requirement, heating is performed through the auxiliary electric heating wire in the annular lower water tank 3.

[0044] Of course, the above description is not limited to the above examples. Technical features not described in the present invention can be achieved by or by using existing technologies, which will not be described here. The above embodiments and drawings are only used to illustrate the technical scheme of the present invention and are not limitations of the present invention. The present invention is described in detail with reference to the preferred implementation methods. Ordinary technicians in this field should understand that changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention do not depart from the purpose of the present invention, and should also fall within the scope of protection of the claims of the present invention.

Claims

1. A high-efficiency molten salt heat storage system, characterized in that: The invention comprises a molten salt tank (2), an annular upper water tank (1) located above the molten salt tank (2), and an annular lower water tank (3) located below the molten salt tank (2), wherein an auxiliary electric heating wire is installed in the annular lower water tank (3), wherein the upper and lower ends of the molten salt tank (2) are respectively connected to a molten salt inlet pipe (6) and a molten salt outlet pipe (7), wherein the annular upper water tank (1) and the annular lower water tank (3) are respectively connected to an inlet pipe (8) and an outlet pipe (9), and further comprises a plurality of heating pipes (4) arranged along the circumference of the molten salt tank (2), wherein the upper and lower ends of the heating pipes (4) are respectively connected to the annular upper water tank (1) and the annular lower water tank (3) by rotation, wherein both sides of the heating pipes (4) are respectively bonded to a heat insulating layer (41) and a heat conducting layer (42), and an outer side of the molten salt tank (2) is provided with a receiving groove for accommodating the heating pipes (4), and the water temperature in the heating pipes (4) is adjusted by rotating the heating pipes (4) to adjust the size of the bonding surface between the heat conducting layer (42) and the receiving groove.

2. A high-efficiency molten salt heat storage system according to claim 1, characterized in that: The lower end surface of the annular upper water tank (1) is provided with an upper slewing bearing (18), the upper end surface of the annular lower water tank (3) is provided with a lower slewing bearing (17), the upper and lower ends of the heating tube (4) are respectively fixedly connected with an upper connecting gear (43) and a lower connecting gear (44), the upper connecting gear (43) meshes with the rotating circle of the upper slewing bearing (18), and the lower connecting gear (44) meshes with the rotating circle of the lower slewing bearing (17), and the annular upper water tank (1) is provided with a driving motor (20) for driving the rotating circle of the upper slewing bearing (18) to rotate.

3. A high-efficiency molten salt heat storage system according to claim 1, characterized in that: It also includes an outer heat-insulating cover (21) that wraps the molten salt tank (2), the heating pipe (4) is located inside the outer heat-insulating cover (21), and a heat-insulating filling layer (22) is provided inside the outer heat-insulating cover (21).

4. The high-efficiency molten salt heat storage system according to claim 1, characterized in that: The upper end of the heating tube (4) is provided with an upper flange (45) located in the annular upper water tank (1), and a sealing gasket is installed between the upper flange (45) and the inner wall of the annular upper water tank (1). The lower end of the heating tube (4) is provided with a lower flange (46) located in the annular lower water tank (3), and a sealing gasket is installed between the lower flange (46) and the inner wall of the annular lower water tank (3). The weight of the annular lower water tank (3) realizes compression and sealing of the two ends of the heating tube (4).

5. A high-efficiency molten salt heat storage system according to claim 4, characterized in that: The lower end of the annular lower water tank (3) is provided with a plurality of circumferentially arranged elastic support mechanisms (15), the elastic support mechanisms (15) comprising a base (154) fixed to the ground, an upper support seat (152) fixedly connected to the lower end surface of the annular lower water tank (3), and a lower support seat (153) located below the upper support seat (152), a spring (151) being provided between the lower support seat (153) and the upper support seat (152), a screw rod (155) passing through the lower support seat (153) being fixedly connected to the base (154), the height of the lower support seat (153) being adjusted by adjusting the position of an adjusting nut (156) on the screw rod (155), thereby adjusting the supporting force applied by the spring (151) to the annular lower water tank (3).

6. A high-efficiency molten salt heat storage system according to claim 1, characterized in that: The water inlet pipe (8) passes through the condensation tank (11), one end of the condensation tank (11) is connected to the annular upper water tank (1) through a steam discharge pipe (10), and the other end of the condensation tank (11) is provided with an upward exhaust port (12) and a downward drain port (13).

7. The high-efficiency molten salt heat storage system according to claim 1, characterized in that: It also includes a pressing mechanism (5) for pressing the middle parts of all the heating tubes (4) into the accommodating groove, and the pressing mechanism (5) is released when the heating tubes (4) rotate.

8. A high-efficiency molten salt heat storage system according to claim 7, characterized in that: The clamping mechanism (5) comprises a fixed ring (51) fixedly connected to the outside of the molten salt tank (2), a floating ring (52) sleeved on the outer ring of the fixed ring (51), and a cylinder (55) for driving the floating ring (52) to move up and down. A pressing plate (53) is provided between the heating tube (4) and the fixed ring (51). A push rod (54) passing through the outer ring of the fixed ring (51) is fixedly connected to the pressing plate (53). The inner ring of the floating ring (52) is provided with a clamping inclined surface.

9. The high-efficiency molten salt heat storage system according to claim 1, characterized in that: A circulation pipe (16) is connected between the molten salt inlet pipe (6) and the molten salt outlet pipe (7), and a circulation pump is installed on the circulation pipe (16).

10. A method for using the high-efficiency molten salt heat storage system according to claim 1, characterized in that: The steps include: a. High-temperature liquid molten salt enters the molten salt tank (2) through the molten salt inlet pipe (6) to achieve heat storage; b. Water enters the annular upper water tank (1) through the water inlet pipe (8), flows to the annular lower water tank (3) through the plurality of heating pipes (4), and finally flows out through the water outlet pipe (9); c. The heating tube (4) is fitted into a containing groove outside the molten salt tank (2) to insulate the molten salt tank (2) and transfer the heat emitted by the molten salt tank (2) to the water in the heating tube (4) through the heat-conducting layer (42) to heat the water. The water temperature in the heating tube (4) is adjusted by rotating the heating tube (4) to adjust the size of the fitting surface between the heat-conducting layer (42) and the containing groove; d. When the contact area between the heat conductive layer (42) and the containing groove is at the maximum and the water temperature does not reach the required level, heating is performed through the auxiliary electric heating wire in the annular lower water tank (3).

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