A valley power storage energy conversion device based on molten salt heat storage

Abstract

The present invention discloses a valley power energy storage and conversion device based on molten salt heat storage, comprising: a cylinder filled with molten salt; a rotating shaft disposed within the cylinder; a propulsion reciprocating unit disposed on the rotating shaft and capable of reciprocating along the axial direction of the rotating shaft as the rotating shaft rotates; a plurality of propulsion structures arranged around the rotating shaft and disposed on the propulsion reciprocating unit; the propulsion structures extending radially from the rotating shaft, with a gap between their outer ends and the inner wall of the cylinder; the propulsion structures capable of rotating synchronously around the central axis of the rotating shaft as the rotating shaft rotates; the propulsion structures having two opposing propulsion base surfaces for propulsing the molten salt during the reciprocating movement of the propulsion reciprocating unit; and a heating mechanism disposed within the cylinder. The present invention has the beneficial effect of improving the fluidity of the molten salt within the cylinder, thereby improving heat exchange efficiency.

Description

Technical Field

[0001] The present invention relates to an energy conversion device, in particular to a valley electricity energy storage energy conversion device based on molten salt heat storage. Background Art

[0002] Molten salt is a molten liquid of inorganic salts or their mixtures. Common molten salts include nitrates, chlorides, fluorides, carbonates, and sulfates. Molten salts offer advantages such as a wide operating temperature range, low vapor pressure, high heat capacity, high stability, and low cost, making them an excellent heat transfer and storage medium.

[0003] Molten salt thermal energy storage is widely used in clean energy. Its energy storage method is formed through a molten salt heat storage cycle and a molten salt heat release cycle. In the molten salt heat storage cycle, the low-temperature molten salt in the cold salt tank is heated by wind power, photovoltaic power, and nighttime off-peak electricity. The heated high-temperature molten salt enters the hot salt tank for storage, completing the molten salt heat storage cycle. In the molten salt heat release cycle, the high-temperature molten salt in the hot salt tank exchanges heat with water through a molten salt pump. The released molten salt enters the cold salt tank for storage, completing the molten salt heat release cycle.

[0004] In the current prior art, the heating of molten salt is mainly achieved through heat exchange through an energy conversion device. For example, the patent application with the prior art publication number CN206131834U discloses a molten salt energy storage device that increases the effective heat storage capacity. A molten salt energy storage device that increases the effective heat storage capacity consists of a salt storage tank welded together with a top cover, a shell and a bottom plate, a molten salt pump, an agitator, an electric heater, heat storage bricks, a feed port, a salt inlet, a manhole, an emptying port, a sight glass hole, a thermocouple, a salt discharge port and a thermal insulation layer. The bottom end of the salt storage tank is provided with heat storage bricks, the bottom of the shell of the salt storage tank is provided with a salt discharge port and an electric heater, the top cover of the salt storage tank is provided with a molten salt pump, an agitator, a manhole, a sight glass hole, an emptying port, a feed port, a salt inlet and a thermocouple, and the top cover and the outer side of the shell of the salt storage tank are provided with a thermal insulation layer. This patent application heats the molten salt by an electric heater and stirs the molten salt with an agitator to improve the efficiency of heat energy conversion. The method is relatively simple, and the fluidity of the molten salt in the salt storage tank is poor, resulting in insufficient contact between it and the electric heater, which in turn affects the heat exchange efficiency. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a valley electricity energy storage and energy conversion device based on molten salt heat storage, thereby improving the fluidity of the molten salt in the cylinder and thus improving the heat exchange efficiency.

[0006] The present invention is achieved through the following technical solutions.

[0007] A valley power energy storage and energy conversion device based on molten salt heat storage, comprising:

[0008] a cylinder filled with molten salt;

[0009] A rotating shaft is arranged in the cylinder;

[0010] A propulsion reciprocating unit is provided on the rotating shaft and can reciprocate along the axial direction of the rotating shaft as the rotating shaft rotates;

[0011] A plurality of propulsion structures are arranged around the rotating shaft and provided on the propulsion reciprocating unit; the propulsion structures extend radially along the rotating shaft, with a gap between their outer ends and the inner wall of the cylinder; the propulsion structures can rotate around the central axis of the rotating shaft synchronously with the rotation of the rotating shaft; the propulsion structures have two opposing propulsion base surfaces for propelling the molten salt during the reciprocating movement of the propulsion reciprocating unit;

[0012] The heating mechanism is arranged in the cylinder.

[0013] As a further improvement of the present invention, it also includes:

[0014] A plurality of support rods surround and are connected to the rotating shaft;

[0015] A plurality of dispersing structures are connected to the support rod; the dispersing structure is formed by extending in a direction parallel to the rotation axis, and has a plurality of dispersing grooves spaced apart from each other and allowing the molten salt to pass through, and the ribs of the dispersing structure located between adjacent dispersing grooves form dispersing ribs for dispersing the molten salt;

[0016] A plurality of connecting rods, one end of which is connected to the propulsion structure and the other end of which is slidably connected to the breaking up structure and can slide along the extension direction of the breaking up structure;

[0017] The inner end of the propulsion structure is slidably connected to the propulsion reciprocating unit and can rotate around the central axis of the rotating shaft on the propulsion reciprocating unit.

[0018] As a further improvement of the present invention, the heating mechanism includes:

[0019] A heating reciprocating unit is provided on the rotating shaft and can reciprocate along the axial direction of the rotating shaft as the rotating shaft rotates;

[0020] A plurality of heating structures are arranged around the rotating shaft and connected to the heating reciprocating unit.

[0021] As a further improvement of the present invention, the heating structure extends radially along the rotating shaft.

[0022] As a further improvement of the present invention, the part of the rotating shaft located in the reciprocating movement range of the propulsion reciprocating unit and the heating reciprocating unit is set as a reciprocating screw, and the propulsion reciprocating unit and the heating reciprocating unit are set as reciprocating screw nuts sleeved on the rotating shaft; at least one guide rod is provided in the cylinder body, the guide rod is parallel to the rotating shaft and passes through the propulsion reciprocating unit and the heating reciprocating unit; the heating reciprocating unit is located between the propulsion reciprocating unit and the support rod.

[0023] As a further improvement of the present invention, an inner stirring blade is installed on the propulsion structure.

[0024] As a further improvement of the present invention, the distance between the inner stirring blade and the rotating shaft on each propulsion structure is different.

[0025] As a further improvement of the present invention, the connecting rod is provided with a mounting frame which passes through the scattering groove and can slide along the scattering groove, and the mounting frame is provided with a peripheral stirring blade.

[0026] As a further improvement of the present invention, the peripheral stirring blades are located in the space between the breaking up structure and the inner wall of the cylinder.

[0027] Beneficial effects of the present invention:

[0028] 1. The propulsion structure can synchronously reciprocate along the axial direction and rotate around the central axis of the rotating shaft, so that the propulsion base can push the molten salt, improve its fluidity and make it fully contact with the heating mechanism, thereby improving the heat exchange efficiency;

[0029] 2. The dispersion structure can physically disperse the molten salt, reducing its viscosity and improving the heat exchange efficiency of the molten salt in the initial stage. At the same time, the dispersion structure can also drive the propulsion mechanism to rotate, streamlining the overall structure.

[0030] 3. The heating structure can move back and forth along the axial direction, expanding the heating range;

[0031] 4. The inner stirring blades set in the propulsion structure can stir the molten salt in the inner space, so that the recommended structure combines the functions of pushing and stirring the molten salt, further improving the contact between the molten salt and the heating mechanism;

[0032] 5. The outer stirring blades can stir the molten salt in the outer space. When used together with the inner stirring blades, they basically cover the molten salt in the cylinder, improving the stirring effect. The outer stirring blades can slide with the connecting rod to expand the stirring range. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings to help understand the objects and advantages of the present invention, wherein:

[0034] Figure 1Schematic diagram of the structure of the valley power energy storage and energy conversion device based on molten salt heat storage. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and implementation examples.

[0036] In this specification, directional terms such as up, down, left, right, front, back, front, back, top, and bottom, which are mentioned or may be mentioned, are defined relative to the configurations shown in the accompanying drawings. The terms "inside" and "outside" refer to directions toward or away from the geometric center of a specific component, respectively. These are relative concepts and may vary depending on the location and usage of the component. Therefore, these or other directional terms should not be construed as restrictive.

[0037] Reference Figure 1 A valley electricity energy storage and energy conversion device based on molten salt heat storage includes a cylinder 1, a rotating shaft 2, a propulsion reciprocating unit 31, multiple propulsion structures 32, and a heating mechanism.

[0038] The cylinder 1 is filled with molten salt and has an input port 11 and an output port 12 on its side for inputting unheated molten salt into the cylinder 1 and outputting heated molten salt after energy conversion. The rotating shaft 2 is disposed within the cylinder 1, with one end extending through one end of the cylinder 1 and being assembled and connected to a drive motor 22 disposed outside the cylinder 1. The drive motor 22 is used to drive the rotating shaft 2 to rotate about its central axis.

[0039] The reciprocating propulsion unit 31 is disposed on the rotating shaft 2 and can reciprocate along the axial direction of the rotating shaft 2 as the rotating shaft 2 rotates. A plurality of propulsion structures 32 are arranged around the rotating shaft 2 and disposed on the reciprocating propulsion structure 32. The propulsion structure 32 extends radially along the rotating shaft 2. The inner end of the propulsion structure 32 is disposed on the reciprocating propulsion structure 32, and a gap is left between the outer end thereof and the inner wall of the cylinder 1. Structurally, the propulsion structure 32 is a flat plate-like structure having two opposing propulsion base surfaces 321, which can propel the molten salt during the reciprocating movement of the reciprocating propulsion unit 31.

[0040] The heating mechanism is arranged in the cylinder 1. The heating mechanism uses valley electricity to heat the molten salt in the cylinder 1, converting electrical energy into thermal energy, thereby realizing energy conversion. The heated high-temperature molten salt is output to the hot salt tank for storage, completing the molten salt heat storage cycle.

[0041] In this embodiment, the space inside the cylinder 1 can be divided into two parts, namely, an inner space 1a and an outer space 1b. The columnar space defined by the outer end of the propulsion structure 32 along the axial direction of the rotating shaft 2 is the inner space 1a, and the remaining part between the outer end of the propulsion structure 32 and the inner wall of the cylinder 1 is the outer space 1b. The rotating shaft 2 drives the propulsion reset unit to move back and forth. During this reciprocating movement, the propulsion structure 32 rotates, and the propulsion base 321 pushes the molten salt in the inner space 1a, so that the molten salt forms a reflux between the inner space 1a and the outer space 1b. On the one hand, it can improve the fluidity of the molten salt in the cylinder 1 and fully contact with the heating mechanism, thereby improving the efficiency of heat exchange. On the other hand, the reflux formed by the molten salt being pushed by the propulsion unit can accelerate the heat transfer of the molten salt, making the temperature of the molten salt in the cylinder 1 more uniform.

[0042] The energy conversion device of this embodiment also includes a plurality of support rods 41, a plurality of disintegration structures 42, and a plurality of connecting rods 43. The support rods 41 extend substantially along the axial direction of the rotating shaft 2 and are connected to the rotating shaft 2 in a circular manner. The disintegration structure 42 is connected to the support rods 41. The disintegration structure 42 extends in a direction parallel to the rotating shaft 2 and is formed as a flat plate-like structure. The disintegration structure 42 has a plurality of disintegration grooves 421 spaced apart from each other and allowing the molten salt to pass through. The ribs of the disintegration structure 42 located between adjacent disintegration grooves 421 form disintegration ribs 422 for disintegrating the molten salt. The disintegration grooves 421 are arranged parallel to the axial direction of the rotating shaft 2. The connecting rod 43 is parallel to the axial direction of the rotating shaft 2, one end of which is connected to the propulsion structure 32 and the other end is slidably connected to the disintegration structure 42 and can slide along the extension direction of the disintegration structure 42. The inner end of the propulsion structure 32 is slidably connected to the propulsion reciprocating unit 31 and can rotate around the central axis of the rotating shaft 2 on the propulsion reciprocating unit 31. More specifically, an annular groove surrounding the rotating shaft is provided on the side of the propulsion reciprocating unit 31, and a slider slidably connected to the annular groove is provided at the inner end of the propulsion structure 32, so that the propulsion structure 32 can slide relative to the propulsion reciprocating unit 31.

[0043] As the heating mechanism heats the molten salt, the temperature gradually increases, while the viscosity of the molten salt gradually decreases. However, when the molten salt is in a low-temperature state, i.e., unheated, its viscosity is relatively high, resulting in relatively weak flow properties. In this embodiment, the breakup structure 42 is driven by the rotating shaft 2 to rotate within the cylinder 1. The breakup ribs 422 can break up the molten salt, physically reducing its viscosity and improving its flow properties during the initial heating phase, thereby enhancing the heat exchange efficiency between the heating mechanism and the molten salt during the initial heating phase.

[0044] In addition, the rotation of the dispersing structure 42 can also drive the propulsion structure 32 through the connecting rod 43, so that the propulsion structure 32 can be driven to move back and forth by the propulsion reciprocating structure while synchronously rotating around the central axis of the rotating shaft 2, so that the propulsion base 321 can push the molten salt, and the molten salt forms a backflow between the inner space 1a and the outer space 1b in the cylinder 1. Therefore, the dispersing structure 42 not only plays the role of dispersing the molten salt and reducing its viscosity, but also drives the propulsion structure 32, reducing the structural configuration within the cylinder 1, making the overall structure more streamlined.

[0045] As for the heating mechanism, it includes a heating reciprocating unit 51 and a plurality of heating structures 52. The heating reciprocating unit 51 is arranged on the rotating shaft 2 and can reciprocate along the axial direction of the rotating shaft 2 as the rotating shaft 2 rotates. The heating structure 52 is arranged around the rotating shaft 2 and is connected to the heating reciprocating unit 51. The movement mode of the heating reciprocating unit 51 is the same as that of the propulsion reciprocating unit 31, so that the heating reciprocating unit 51 can drive the heating structure 52 to reciprocate along the axial direction of the rotating shaft 2 when the rotating shaft 2 rotates, which can increase the heating area of ​​the heating structure 52, further improve the mutual contact and heat exchange between the molten salt and the heating structure 52, and thereby improve the efficiency of heat exchange.

[0046] Furthermore, the heating structure 52 extends along the axial direction of the rotating shaft 2, so that its extension direction and the direction in which the propulsion structure 32 pushes the molten salt flow are mutually perpendicular, thereby further improving the degree of contact between the molten salt and the heating structure 52. More specifically, the reciprocating cycles of the propulsion reciprocating unit 31 and the heating reciprocating unit 51 are consistent, and the movement directions of the two are always opposite, that is, the movement direction of the heating structure 52 is always opposite to the flow direction of the molten salt, so that the heating structure 52 and the molten salt fluid contact in a manner that is similar to "colliding" with each other, thereby further enhancing the heat exchange effect between the heating structure 52 and the molten salt. In addition, the heating structure 52 is preferably a flat structure, and its two opposing surfaces are both perpendicular to the axial direction of the rotating shaft 2. The heating body of the heating structure 52 is mainly arranged on two surfaces, which constitute the heating surfaces 521 of the heating structure 52. During the reciprocating movement of the heating structure 52, the two heating surfaces 521 alternately "collide" with the molten salt fluid to exchange heat, thereby maximizing the heat exchange effect of the heating structure 52.

[0047] As for the reciprocating movement of the propulsion reciprocating unit 31 and the heating reciprocating unit 51, in this embodiment, the portion of the rotating shaft 2 located within the moving range of the propulsion reciprocating unit 31 and the heating reciprocating unit 51 is set as a reciprocating screw 2a, and the remaining portion can be set as a smooth shaft. The propulsion reciprocating unit 31 and the heating reciprocating unit 51 are set as reciprocating screw nuts sleeved on the rotating shaft 2. At least one guide rod 21 is set in the cylinder 1, and the guide rod 21 is set parallel to the rotating shaft 2. The guide rod 21 passes through the propulsion reciprocating unit 31 and the heating reciprocating unit 51. Usually, two to three guide rods 21 are provided, and one end thereof is fixed to the end of the cylinder 1. The heating reciprocating unit 51 is located between the propulsion reciprocating unit 31 and the support rod 41 to avoid interference between the guide rod 21 and the support rod 41. In addition, the heating reciprocating unit 51 and the heating structure 52 are located in the middle position in the cylinder 1, which is beneficial to the heating of the molten salt as a whole.

[0048] To further improve the heat exchange efficiency between the molten salt and the heating structure 52, the propulsion structure 32 is equipped with inner stirring blades 61. The inner stirring blades 61 can be provided on both propulsion base surfaces 321 of the propulsion structure 32. During the synchronous axial reciprocating movement of the propulsion structure 32 and the rotation around the central axis of the rotating shaft 2, the inner stirring blades 61 stir the molten salt in the inner space 1a. After being equipped with the inner stirring blades 61, the propulsion structure 32 can combine the functions of propulsing and stirring the molten salt, thereby further improving the heat exchange efficiency.

[0049] To ensure more uniform stirring of the molten salt within the inner space 1a, the distance between the inner stirring blades 61 and the rotating shaft 2 on each propulsion structure 32 is different, thereby increasing the overall coverage of the inner stirring blades 61 and improving the stirring effect. It should be noted that the inner stirring blades 61 can also accelerate the diffusion of the molten salt from the inner space 1a to the outer space 1b due to the centrifugal effect, further enhancing the effectiveness of the propulsion structure 32.

[0050] Furthermore, the connecting rod 43 is provided with a mounting bracket 431. The mounting bracket 431 passes through the scattering groove 421 of the scattering structure 42 and can slide along the scattering groove 421, so that the connecting rod 43 is slidably connected to the scattering structure 42. The mounting bracket 431 is mounted with a peripheral stirring blade 62. The peripheral stirring blade 62 can also stir the molten salt as the scattering structure 42 rotates, thereby further improving the stirring effect. Because the connecting rod 43 is slidably connected to the scattering structure 42, the peripheral stirring blade 62 can reciprocate along the scattering structure 42, thereby expanding the stirring range of the peripheral stirring blade 62.

[0051] In addition, the peripheral stirring blades 62 are located in the space between the breaking up structure 42 and the inner wall of the cylinder 1, so that the molten salt in the peripheral space 1b can be stirred by the peripheral stirring blades 62. The combination of the peripheral stirring blades 62 and the inner stirring blades 61 can basically cover the stirring of the molten salt in the cylinder 1, thereby further improving the stirring effect.

[0052] Finally, it should be noted that the above implementation cases are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above implementation cases, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the above implementation cases, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the implementation cases of the present invention.

Claims

1. A valley power energy storage and energy conversion device based on molten salt heat storage, characterized in that: include: a cylinder filled with molten salt; A rotating shaft is arranged in the cylinder; A propulsion reciprocating unit is provided on the rotating shaft and can reciprocate along the axial direction of the rotating shaft as the rotating shaft rotates; A plurality of propulsion structures are arranged around the rotating shaft and provided on the propulsion reciprocating unit, with their inner ends slidably connected to the propulsion reciprocating unit and rotatable around the central axis of the rotating shaft on the propulsion reciprocating unit; the propulsion structures extend radially along the rotating shaft, with a gap between their outer ends and the inner wall of the cylinder; the propulsion structures can rotate around the central axis of the rotating shaft synchronously with the rotation of the rotating shaft; the propulsion structures have two opposing propulsion base surfaces for propelling the molten salt during the reciprocating movement of the propulsion reciprocating unit; and an inner stirring blade is installed on the propulsion structure; a heating mechanism disposed within the barrel, comprising a heating reciprocating unit disposed on the rotating shaft and capable of reciprocating along the axial direction of the rotating shaft as the rotating shaft rotates, wherein the reciprocating cycles of the propulsion reciprocating unit and the heating reciprocating unit are consistent, and their moving directions are always opposite; and a plurality of heating structures arranged around the rotating shaft and connected to the heating reciprocating unit; A plurality of support rods surround and are connected to the rotating shaft; A plurality of dispersing structures are connected to the support rod; the dispersing structure is formed by extending in a direction parallel to the rotation axis, and has a plurality of dispersing grooves spaced apart from each other and allowing the molten salt to pass through, and the ribs of the dispersing structure located between adjacent dispersing grooves form dispersing ribs for dispersing the molten salt; Multiple connecting rods, one end of which is connected to the propulsion structure and the other end is slidably connected to the scattering structure, and can slide along the extension direction of the scattering structure; the connecting rods are provided with a mounting frame that passes through the scattering groove and can slide along the scattering groove, and the mounting frame is equipped with a peripheral stirring blade, and the peripheral stirring blade is located in the space between the scattering structure and the inner wall of the cylinder.

2. The valley electricity energy storage and energy conversion device based on molten salt heat storage according to claim 1 is characterized in that: The heating structure extends radially along the rotating shaft.

3. The valley electricity energy storage and energy conversion device based on molten salt heat storage according to claim 1 is characterized in that: The part of the rotating shaft located in the reciprocating movement range of the propulsion reciprocating unit and the heating reciprocating unit is set as a reciprocating screw, and the propulsion reciprocating unit and the heating reciprocating unit are set as reciprocating screw nuts sleeved on the rotating shaft; at least one guide rod is provided in the cylinder, the guide rod is parallel to the rotating shaft and passes through the propulsion reciprocating unit and the heating reciprocating unit; the heating reciprocating unit is located between the propulsion reciprocating unit and the support rod.

4. The valley electricity energy storage and energy conversion device based on molten salt heat storage according to claim 1 is characterized in that: The distance between the inner stirring blade and the rotating shaft on each propulsion structure is different.

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