CN217866105U - High-temperature molten salt storage tank with thermal barrier coating - Google Patents
High-temperature molten salt storage tank with thermal barrier coating Download PDFInfo
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- CN217866105U CN217866105U CN202222280684.8U CN202222280684U CN217866105U CN 217866105 U CN217866105 U CN 217866105U CN 202222280684 U CN202222280684 U CN 202222280684U CN 217866105 U CN217866105 U CN 217866105U
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Abstract
The utility model relates to the field of energy storage type solar photothermal devices, in particular to a high-temperature molten salt storage tank with a thermal barrier coating, which comprises a tank top, a tank wall and a tank bottom, wherein the tank wall sequentially comprises a first ceramic layer, a first binder layer, a first carbon steel layer and a heat preservation layer from inside to outside; the tank bottom includes second ceramic layer, second binder layer, second carbon steel layer, gravel layer, first firebrick layer, foam glass layer and heat-resisting concrete layer from top to bottom in proper order, the foam glass layer is located tank bottom middle part, is located foam glass layer periphery and encircles to being provided with second firebrick layer, the second firebrick layer is located between first firebrick layer and the heat-resisting concrete layer. The utility model discloses utilize the binder layer to bond the ceramic layer to first carbon steel layer and second carbon steel internal surface, the fused salt can not make the jar wall produce higher temperature gradient storing-exothermic in-process, and then weakens the degree that high temperature creep and peak stress caused the damage, promotes the in service life-span of storage tank.
Description
Technical Field
The utility model relates to an energy storage type solar energy light and heat device field specifically is a high temperature fused salt storage tank of adhering to thermal barrier coating.
Background
The solar photo-thermal power generation technology (CSP) is an energy utilization mode with a wide application prospect, and by the end of 2021, 142 photo-thermal projects are grid-connected to generate electricity globally, and the cumulative installed capacity is about 6.8GW. At present, 8 commercial photo-thermal power stations are successfully connected to the grid for power generation in China, and the proposed molten salt energy storage type CSP project exceeds 2.16GW. It is worth noting that the operating characteristics of unstable solar radiation energy time-space intermittence caused by cloud layer shielding and unmatched power generation and power utilization periods caused by day-night circulation lead the CSP system to urgently solve the problem of heat storage so as to improve the stability and continuity of the whole system and enable the power station to continuously meet the power generation requirement under the condition that the power station cannot receive solar energy resources.
At present, energy storage type photo-thermal power stations all adopt a double-tank (high-temperature tank and low-temperature tank) molten salt heat storage mode, taking a tower type CSP system with the widest application prospect as an example, during heat storage, 565 ℃ hot molten salt coming from a heat absorber is pumped into a high-temperature tank body. When heat is released, the hot molten salt enters the steam generator again to release heat, and the steam turbine is pushed to do work and generate electricity. And then, the cold molten salt with the temperature reduced to 290 ℃ returns to the low-temperature tank, and enters the heat absorber to be heated to a high-temperature state when the illumination is sufficient, so that the circulation is repeated, and the requirement of 24h uninterrupted power generation can be met.
However, for high temperature molten salt storage tanks, the following problems are still encountered during long cycle, multi-cycle, high temperature operation: (1) At present, 347H stainless steel with high cost is often selected as a tank body material for a high-temperature storage tank with the operation temperature of 565 ℃ and the creep temperature of the high-temperature storage tank is 538 ℃. During heat storage, under the long-period action of 565 ℃ high-temperature molten salt, the wall surface of the stainless steel tank body is easy to generate irreversible creep damage of slow plastic deformation, and potential safety hazards are caused to the operation of the tank body. (2) In the storage-heat release process, high-temperature molten salt with the liquid level not less than 1m can be reserved in the tank body, so that the bottom plate and the lowermost wallboard of the tank body are always in a high-temperature creep state, and the risk of failure of the storage tank is further increased. (3) Storage tanks in CSP power stations are all vertical cylindrical steel welding structures, and stress concentration is easily generated at large-angle welding positions where wall plates and bottom plates are connected. Particularly, the higher wall surface temperature gradient can further improve the stress level of the fillet weld position, so that the weld structure generates stress plastic damage; in a long-period storage-heat release cycle, dynamic stress plastic damage accumulation easily causes the low-cycle or high-cycle fatigue failure phenomenon of the wall surface of the tank body. (4) The high-temperature creep and stress fatigue synergistic effect can accelerate the fracture failure rate of the high-temperature molten salt storage tank, and molten salt leakage is easily caused. For example, the high temperature storage tanks of the united states creatent Dunes and spain GemaSolar tower power station produced creep and fatigue-induced molten salt leakage accidents in 2016 and 2017, and caused millions of dollars of economic loss. Particularly, with the continuous development of the fourth generation CSP technology of the coupling supercritical carbon dioxide Brayton cycle with low cost and high efficiency, the working temperature of the molten salt medium reaches about 700 ℃. Based on this, in the face of the high-cost tank body material and the continuously increased molten salt operation temperature, how to effectively reduce the temperature level of the wall surface of the storage tank on the premise of meeting the storage-heat release capacity so as to improve the creep and fatigue damage phenomena caused by the high temperature of the wall surface, thereby improving the operation safety performance of the whole system becomes one of the problems to be solved urgently in the CSP system.
SUMMERY OF THE UTILITY MODEL
The utility model discloses a reduce the high temperature creep time of jar material, and then weaken the high temperature creep damage to the influence of storage tank security performance, provide a high temperature fused salt storage tank of adhering to thermal barrier coating.
The utility model discloses a realize through following technical scheme: a high-temperature molten salt storage tank with a thermal barrier coating comprises a tank top, a tank wall and a tank bottom,
the tank wall sequentially comprises a first ceramic layer, a first binder layer, a first carbon steel layer and a heat insulation layer from inside to outside;
the tank bottom includes second ceramic layer, second binder layer, second carbon steel layer, gravel layer, first firebrick layer, foam glass layer and heat-resisting concrete layer from top to bottom in proper order, the foam glass layer is located tank bottom middle part, is located foam glass layer periphery and encircles to being provided with second firebrick layer, the second firebrick layer is located between first firebrick layer and the heat-resisting concrete layer.
As a further improvement of the technical scheme of the utility model, the outer fringe of second ceramic layer extends to first ceramic layer lower surface.
As the technical scheme of the utility model further improve, the outer fringe on second carbon steel layer flushes with the outer wall of heat preservation, and welded connection between second carbon steel layer and the first carbon steel layer.
As the utility model discloses technical scheme's further improvement, first carbon steel layer is including last crown plate and the lower crown plate that from top to bottom sets gradually, the inner wall of going up crown plate and lower crown plate flushes, and the thickness of lower crown plate is greater than the thickness of the upper ring plate.
As the utility model discloses technical scheme's further improvement, second carbon steel layer includes interior crown plate and the outer crown plate that sets gradually from inside to outside, the upper surface of interior crown plate and outer crown plate flushes, and the outer crown plate thickness is greater than interior crown plate thickness.
As a further improvement of the technical scheme of the utility model, be provided with the cooling tuber pipe in the heat-resisting concrete layer.
As the technical scheme of the utility model further improve, the outer fringe on gravel layer, first firebrick layer, second firebrick layer and heat-resisting concrete layer all extends to the jar wall periphery.
As a further improvement of the technical proposal of the utility model, the upper ring plate is connected with the lower ring plate by welding.
As a further improvement of the technical scheme of the utility model, welded connection between interior crown plate and the outer crown plate.
As the technical scheme of the utility model further improve, the tank deck includes vault and support, the vault passes through the support to be supported in tank wall top, through angle steel welded connection between support and the first carbon steel layer.
High temperature fused salt storage tank of adhering to thermal barrier coating, compare with prior art, have following beneficial effect:
1. the utility model discloses utilize the binder layer to bond the ceramic layer to first carbon steel layer and second carbon steel internal surface, the fused salt can not make the jar wall produce great temperature gradient storing-exothermic in-process, and then weakens the degree that high temperature creep and peak stress caused the damage, promotes the in service life-span of storage tank.
2. The utility model discloses at jar wall inner wall adhesion ceramic layer, can effectively keep apart jar body and fused salt fluid in the operation in-process, through reducing wall temperature level in order to reach the thermal-insulated effect that keeps warm, make the operation thermal efficiency higher. The peak stress level of the large-angle welding line is weakened by reducing the temperature of the wall surface, and further the influence of stress plastic damage on the safety performance of the storage tank is reduced.
3. The utility model discloses at jar wall inner wall adhesion ceramic layer, can reduce jar wall temperature, can reduce jar high temperature creep resistance, stress damage resistance ability and the requirement of anti molten salt corrosion resistance of the body, increase jar the material selection scope of the body, reduce the initial investment cost.
4. The utility model discloses in the ceramic layer has now been used widely on aeroengine hot junction part, has gained unusual effect in the aspect of the thermal-insulated aspect of cooling, so the utility model discloses have good application prospect, be one kind and realize prolonging jar body thermal protection technique of the life-span of being on active service under complicated harsh environment.
5. The utility model provides a tank bottoms foundation structure has both satisfied the bearing requirement of storage tank, has reduced the calorific loss of system again.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the technical solutions in the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic view showing the connection between the top and the wall of the high temperature molten salt storage tank with thermal barrier coating according to the present invention (the thermal insulation layer is not shown in the figure).
Fig. 2 is a schematic view of the connection of the tank wall and the tank bottom.
In the figure: 1-tank top, 101-vault, 102-bracket, 103-angle steel, 2-tank wall, 201-first ceramic layer, 202-first adhesive layer, 203-first carbon steel layer, 204-insulating layer, 213-upper ring plate, 223-lower ring plate, 3-tank bottom, 301-second ceramic layer, 302-second adhesive layer, 303-second carbon steel layer, 304-gravel layer, 305-first firebrick layer, 306-foam glass layer, 307-heat-resistant concrete layer, 308-second firebrick layer, 309-cooling air pipe, 313-inner ring plate, 323-outer ring plate.
Detailed Description
The technical solutions of the present invention will be described clearly and completely below, and it should be apparent that the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; may be a mechanical connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.
The utility model provides a specific embodiment of a high-temperature molten salt storage tank with a thermal barrier coating, which comprises a tank top 1, a tank wall 2 and a tank bottom 3,
the tank wall 2 sequentially comprises a first ceramic layer 201, a first binder layer 202, a first carbon steel layer 203 and a heat insulation layer 204 from inside to outside;
tank bottom 3 includes second ceramic layer 301, second binder layer 302, second carbon steel layer 303, gravel layer 304, first firebrick layer 305, foam glass layer 306 and heat-resisting concrete layer 307 from top to bottom in proper order, foam glass layer 306 is located tank bottom 3 middle part, is located the peripheral hoop of foam glass layer 306 and is provided with second firebrick layer 308, second firebrick layer 308 is located between first firebrick layer 305 and the heat-resisting concrete layer 307.
In this embodiment, the first ceramic layer 201 is attached to the surface of the first carbon steel layer 203 by the first adhesive layer 202, and the second ceramic layer 301 is attached to the surface of the second carbon steel layer 303 by the second adhesive layer 302, wherein the carbon steel layer is made of a carbon steel material which is heat-resistant, molten salt corrosion-resistant and low in cost (the creep temperature of the material A516Gr.70 is 343 ℃). The ceramic layer is made of zirconia ceramic, and the zirconia ceramic with the thickness of 150 mu m can realize the cooling effect of about 170K. Meanwhile, the zirconia ceramic layer occupies a small space, does not influence the heat storage and release capacity of the tank body, has stable chemical properties, has better high-temperature corrosion resistance and is not easy to react with high-temperature molten salt. In this embodiment, taking zirconia ceramics as an example, the thickness of the first ceramic layer 201 and the second ceramic layer 301 is 250-350 μm.
In specific implementation, the binder used in the binder layer may be a NiCrAlY material, a FeCrAlY material, a CoCrAlY material, a NiCoCrAlY material, or a PtAl material.
When the method is applied specifically, the first adhesive layer 202 is coated on the inner surface of the first carbon steel layer 203, the second adhesive layer 302 is coated on the inner surface of the second carbon steel layer 303, then the first ceramic layer 201 with low thermal conductivity, high temperature resistance and corrosion resistance is sprayed on the inner surface of the first adhesive layer 202, and the second ceramic layer 301 is sprayed on the inner surface of the second adhesive layer 302, and the adhesive layer and the ceramic layer together form the thermal barrier coating of the tank body. The tank wall 2 and the tank bottom 3 are isolated from the high-temperature molten salt, so that the temperature of the tank body is effectively reduced, and the high-temperature creep damage resistance and the stress plastic damage resistance of the tank body are improved, so that the service life of the molten salt storage tank is prolonged. The insulating layer 204 is the outermost layer and coats the first carbon steel layer 203 so as to reduce the heat loss of the tank body. The thermal barrier coating covers the entire tank wall 2 and the inner surface of the tank bottom 3 and may further reduce the higher peak stresses caused by high temperatures by increasing the thickness of the thermal barrier coating at the fillet joint.
As shown in fig. 2, the outer edge of the second ceramic layer 301 extends to the lower surface of the first ceramic layer 201.
In this embodiment, the outer edge of the second carbon steel layer 303 is flush with the outer wall of the insulating layer 204, and the second carbon steel layer 303 is welded to the first carbon steel layer 203.
As shown in fig. 2, the first carbon steel layer 203 includes an upper ring plate 213 and a lower ring plate 223 that are sequentially disposed from top to bottom, inner walls of the upper ring plate 213 and the lower ring plate 223 are flush, and a thickness of the lower ring plate 223 is greater than a thickness of the upper ring plate 213. The thickness of the lower ring plate 223 is greater than that of the upper ring plate 213, so that the supporting strength of the first carbon steel layer 203 can be improved. Preferably, the upper ring plate 213 and the lower ring plate 223 are welded together.
As shown in fig. 2, the second carbon steel layer 303 includes an inner ring plate 313 and an outer ring plate 323 sequentially arranged from inside to outside, the upper surfaces of the inner ring plate 313 and the outer ring plate 323 are flush, and the thickness of the outer ring plate 323 is greater than that of the inner ring plate 313. The thickness of the outer ring plate 323 is larger than that of the inner ring plate 313, so that the supporting strength of the second carbon steel layer 303 on the tank wall 2 can be improved. Furthermore, in order to facilitate the construction and installation of the second carbon steel layer 303, the inner ring plate 313 and the outer ring plate 323 are welded.
In specific implementation, a cooling air duct 309 is arranged in the heat-resistant concrete layer 307. The purpose of the cooling air duct 309 is to ensure that the temperature of the foundation is controlled at around 75 ℃.
In a specific application, in order to improve the supporting strength of the tank bottom 3, the outer edges of the gravel layer 304, the first refractory brick layer 305, the second refractory brick layer 308 and the heat-resistant concrete layer 307 extend to the periphery of the tank wall 2.
In addition to the zirconia ceramic layer, the first ceramic layer 201 and/or the second ceramic layer 301 may employ a perovskite ceramic layer, a pyrochlore ceramic layer, a fluorite ceramic layer, or a magnetoplumbite ceramic layer.
In addition, the heat insulation layer 204 is made of aluminum silicate rock wool. In this embodiment, C30 concrete is used as the heat-resistant concrete layer 307.
In the embodiment, the tank top 1 comprises a dome 101 and a bracket 102, the dome 101 is supported on the top of the tank wall 2 through the bracket 102, and the bracket 102 is connected with the first carbon steel layer 203 through an angle steel 103 in a welding mode. Specifically, one side of the angle steel 103 is welded to the bracket 102, and the other side of the angle steel 103 is welded to the first carbon steel layer 203.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.
Claims (10)
1. A high-temperature molten salt storage tank with a thermal barrier coating comprises a tank top (1), a tank wall (2) and a tank bottom (3),
the tank wall (2) sequentially comprises a first ceramic layer (201), a first adhesive layer (202), a first carbon steel layer (203) and a heat insulation layer (204) from inside to outside;
tank bottom (3) include second ceramic layer (301), second binder layer (302), second carbon steel layer (303), gravel layer (304), first firebrick layer (305), foam glass layer (306) and heat-resisting concrete layer (307) from top to bottom in proper order, foam glass layer (306) are located tank bottom (3) middle part, are located foam glass layer (306) peripheral hoop and are provided with second firebrick layer (308), second firebrick layer (308) are located between first firebrick layer (305) and heat-resisting concrete layer (307).
2. The high-temperature molten salt storage tank with thermal barrier coating attached as claimed in claim 1, wherein the outer edge of the second ceramic layer (301) extends to the lower surface of the first ceramic layer (201).
3. The high-temperature molten salt storage tank with the thermal barrier coating attached thereon as claimed in claim 1, wherein the outer edge of the second carbon steel layer (303) is flush with the outer wall of the thermal insulation layer (204), and the second carbon steel layer (303) is welded with the first carbon steel layer (203).
4. The high-temperature molten salt storage tank with thermal barrier coating attached as claimed in claim 1, wherein the first carbon steel layer (203) comprises an upper annular plate (213) and a lower annular plate (223) which are arranged from top to bottom in sequence, the inner walls of the upper annular plate (213) and the lower annular plate (223) are flush, and the thickness of the lower annular plate (223) is greater than that of the upper annular plate (213).
5. The high-temperature molten salt storage tank with thermal barrier coating attached as claimed in claim 1, wherein the second carbon steel layer (303) comprises an inner annular plate (313) and an outer annular plate (323) which are arranged from inside to outside in sequence, the upper surfaces of the inner annular plate (313) and the outer annular plate (323) are flush, and the thickness of the outer annular plate (323) is larger than that of the inner annular plate (313).
6. The high-temperature molten salt storage tank with thermal barrier coating attached as claimed in claim 1, wherein a cooling air pipe (309) is arranged in the heat-resistant concrete layer (307).
7. A high temperature molten salt storage tank with thermal barrier coating attached as claimed in claim 1, characterized in that the gravel layer (304), the first refractory brick layer (305), the second refractory brick layer (308) and the outer edges of the heat resistant concrete layer (307) all extend to the periphery of the tank wall (2).
8. The high-temperature molten salt storage tank with thermal barrier coating attached as claimed in claim 4, characterized in that the upper ring plate (213) and the lower ring plate (223) are welded together.
9. A high temperature molten salt storage tank with thermal barrier coating attached as claimed in claim 5, characterized in that the inner ring plate (313) and the outer ring plate (323) are welded together.
10. The high-temperature molten salt storage tank with the thermal barrier coating attached is characterized in that the tank roof (1) comprises a vault (101) and a bracket (102), the vault (101) is supported on the top of the tank wall (2) through the bracket (102), and the bracket (102) is connected with the first carbon steel layer (203) through angle steel (103) in a welding mode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222280684.8U CN217866105U (en) | 2022-08-30 | 2022-08-30 | High-temperature molten salt storage tank with thermal barrier coating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222280684.8U CN217866105U (en) | 2022-08-30 | 2022-08-30 | High-temperature molten salt storage tank with thermal barrier coating |
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| Publication Number | Publication Date |
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| CN217866105U true CN217866105U (en) | 2022-11-22 |
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| CN202222280684.8U Active CN217866105U (en) | 2022-08-30 | 2022-08-30 | High-temperature molten salt storage tank with thermal barrier coating |
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- 2022-08-30 CN CN202222280684.8U patent/CN217866105U/en active Active
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