Anti-freezing and anti-blocking heat absorber used in fused salt tower type photo-thermal power station system

Abstract

The utility model relates to the technical field of research and development of solar heat absorbers, in particular to an anti-freezing and anti-blocking heat absorber used in a fused salt tower type photo-thermal power station system. The solar heat absorber comprises a heat absorber body and a plane mirror, the heat absorber body comprises a lower bent pipe and a heat absorption pipe panel, the lower bent pipe is installed in the bottom of the heat absorber body, the heat absorption pipe panel is located above the lower bent pipe, and the outlet end of the heat absorption pipe panel communicates with the inlet end of the lower bent pipe; the plane mirror is installed on the bottom wall, facing the outside, of the top of the heat absorber body and located above the auxiliary heating mirror field. By arranging the auxiliary heating mirror field and the plane mirror, sunlight can be projected on the plane mirror through the auxiliary heating mirror field, then the sunlight is irradiated to the position, close to the lower bent pipe, of the heat absorption pipe panel through reflection of the plane mirror, the heat of the sunlight is absorbed by the heat absorption pipe panel, and the heat is transmitted to the lower bent pipe; therefore, crystallized fused salt frozen and blocked in the lower bent pipe is melted, and the generating capacity is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of solar energy heat absorber research and development, in particular to an anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system. Background Art

[0002] A heat absorber, also known as a solar energy heat absorber, is one of the core key devices in a molten salt tower type solar thermal power station system. It absorbs heat from sunlight and transfers it to a heat transfer medium, usually molten salt. The solar energy heat absorber is usually located at the top of a high tower and receives solar radiation reflected and focused by thousands of heliostats, so as to transfer the heat in sunlight to the heat transfer medium.

[0003] However, the lower elbow of the current solar energy heat absorber is usually a position that cannot be irradiated by the reflection of the heliostat, that is, it can also be called a non-light spot area. In the case of relatively cold weather and low temperature, the molten salt in the lower elbow is extremely easy to freeze and block, thereby affecting the flow of the molten salt and unable to transfer heat, seriously affecting the power generation of the molten salt tower type solar thermal power station system. Summary of the Utility Model

[0004] (1) Technical Problems to be Solved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the utility model provides an anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system, which solves the technical problem that the molten salt in the lower elbow of the non-light spot area is extremely easy to freeze and block in the case of relatively cold weather and low temperature, thereby affecting the flow of the molten salt and unable to transfer heat, seriously affecting the power generation of the molten salt tower type solar thermal power station system.

[0006] (2) Technical Solutions

[0007] In order to achieve the above object, the main technical solutions adopted by the utility model include:

[0008] The present utility model provides an anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system. The molten salt tower type solar thermal power station system includes an auxiliary heat mirror field installed on the ground. The anti-freezing and anti-blocking heat absorber includes a heat absorber body and a plane mirror. The heat absorber body includes a downward bent pipe and a heat absorption tube screen. The downward bent pipe is installed inside the bottom of the heat absorber body. The heat absorption tube screen is located above the downward bent pipe, and the outlet end of the heat absorption tube screen is communicated with the inlet end of the downward bent pipe. The plane mirror is installed on the bottom wall facing the outside at the top of the heat absorber body and is located above the auxiliary heat mirror field so that it can receive the sunlight projected by the auxiliary heat mirror field. The plane mirror can reflect the projected sunlight to the position of the heat absorption tube screen close to the downward bent pipe, so that the heat absorption tube screen can absorb the heat of the sunlight and transfer the heat to the downward bent pipe to melt the crystallized molten salt frozen in the downward bent pipe.

[0009] Preferably, the heat absorber body further includes a first outer shell and a second outer shell. The first outer shell is located above the second outer shell, and the heat absorption tube screen is located between the first outer shell and the second outer shell. The plane mirror is installed on the bottom wall of the first outer shell, the inner wall of the plane mirror is attached to the outer wall of the heat absorption tube screen, and the outer wall of the plane mirror is flush with the outer side wall of the first outer shell. The downward bent pipe is installed inside the second outer shell. One end of the downward bent pipe is communicated with the heat absorption tube screen, and the other end is communicated with a lower header inside the second outer shell. The lower header is installed on the inner bottom wall of the second outer shell. The plane mirror can reflect the sunlight irradiated on the auxiliary heat mirror field to the position of the heat absorption tube screen close to the downward bent pipe.

[0010] Preferably, the downward bent pipe includes a first pipe section and a second pipe section. One end of the first pipe section is communicated with the heat absorption tube screen, and the other end is communicated with the second pipe section through an expanding joint. The diameter of the end of the expanding joint connected to the first pipe section is smaller than the diameter of the end of the expanding joint connected to the second pipe section.

[0011] Preferably, the expanding joint includes a first connecting section, an expanding section and a second connecting section which are sequentially communicated. The ratio range of the diameter of the second connecting section to the diameter of the first connecting section is 1.2 - 1.6.

[0012] Preferably, the length ranges of both the first connecting section and the second connecting section are 10 mm - 50 mm.

[0013] Preferably, the anti-freezing and plugging heat absorber further includes an electric tracing device; the heat absorption tube screen includes a plurality of heat absorption tubes, a plurality of lower bent tubes are provided, and the plurality of lower bent tubes are in one-to-one communication with the plurality of heat absorption tubes. The electric tracing device is sleeved on the outer walls of the plurality of lower bent tubes one by one through a wire mesh for assisting in heating the molten salt in the plurality of lower bent tubes.

[0014] Preferably, the heat absorber body further includes an elastic member; an upper header is installed in the first outer shell, the top of the upper header is connected to the top wall inside the first outer shell, and the bottom of the upper header is communicated with the heat absorption tube screen through a plurality of upper bent tubes. The bottom of the elastic member passes through the first outer shell and is connected to the upper header.

[0015] Preferably, both the upper bent tube and the lower bent tube are in a U-shaped configuration arranged horizontally.

[0016] Preferably, heat insulation layers are provided on the outer walls of the first outer shell, the second outer shell, and the heat absorption tube screen.

[0017] (III) Beneficial Effects

[0018] The beneficial effects of the present invention are as follows:

[0019] 1. For the anti-freezing and plugging heat absorber in a molten salt tower type solar thermal power station system of the present invention, by providing an auxiliary heat mirror field and a plane mirror on the bottom wall at the top of the heat absorber body, when the molten salt in the lower bent tube freezes and plugs, since the lower bent tube is usually a position where sunlight cannot shine, that is, a spotless area, the auxiliary heat mirror field can reflect the sunlight projected thereon to the plane mirror, and then through the reflection of the plane mirror, the sunlight is reflected to the position of the lower bent tube, so as to absorb the heat of the sunlight through the heat absorption tube screen and transfer the heat of the sunlight to the position of the lower bent tube, so as to melt the frozen and plugged crystalline molten salt in the lower bent tube by the heat of the sunlight, thus avoiding the phenomenon of freezing and plugging of the molten salt in the lower bent tube, and further avoiding affecting the flow of the molten salt, and thus avoiding affecting the power generation. By providing the auxiliary heat mirror field and the plane mirror, the present invention can make the sunlight be projected on the plane mirror through the auxiliary heat mirror field, and then through the reflection of the plane mirror, the sunlight shines on the position of the heat absorption tube screen close to the lower bent tube. The heat absorption tube screen absorbs the heat of the sunlight and transfers the heat to the position of the lower bent tube to melt the crystalline molten salt frozen and plugged in the lower bent tube, improving the power generation.

[0020] 2. An anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system of the present utility model. By installing a plane mirror on the bottom wall of the first outer shell, and making the inner wall of the plane mirror fit with the outer wall of the heat absorption tube screen, and the outer wall of the plane mirror flush with the outer side wall of the first outer shell, it can enable the plane mirror to receive the sunlight projected by the auxiliary heat mirror field to the maximum extent, so that the plane mirror can irradiate more heat of the sunlight onto the heat absorption tube screen, transfer more heat of the sunlight from the heat absorption tube screen to the downward bent pipe, improve the heat absorption efficiency of the heat absorption tube screen and the downward bent pipe, so that the crystallized molten salt frozen and blocked in the downward bent pipe can be quickly melted, so as not to affect the power generation.

[0021] 3. An anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system of the present utility model. By setting an expansion joint, it can enable the molten salt fluid in the first pipe section to enter the second pipe section more smoothly and with a larger flow rate, improving the power generation capacity. By dividing the expansion joint into a first connection section, a second connection section and an expansion section, the expansion section can make the transition of the molten salt fluid from the first connection section to the second connection section smoother, reducing the resistance of the molten salt fluid passing through the expansion joint. The diameter of the second connection section is 1.2 - 1.6 times that of the first connection section, which can reduce the pressure drop when the fluid passes through the joint, reduce the turbulence phenomenon, and make the molten salt fluid flow more smoothly. By setting the length ranges of both the first connection section and the second connection section to be 10 mm - 50 mm, it can make the connection between the first connection section and the second connection section and the first pipe section and the second pipe section more stable when they are connected respectively.

[0022] 4. An anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system of the present utility model. By setting an electric tracing device, it can realize the auxiliary heating of multiple downward bent pipes. So in cloudy days or when the temperature is too cold, in order to ensure that the molten salt in the downward bent pipe does not freeze and block, the downward bent pipe can be heated by the electric tracing device to ensure that the molten salt can remain in a liquid state under any weather conditions, avoiding the blockage problem caused by freezing and improving the overall reliability of the system.

[0023] 5. An anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system of the present utility model. By setting an elastic member, it can not only enable the upper header to have a certain displacement space during thermal expansion, thereby reducing the thermal stress caused by temperature changes, avoiding damage to the upper header and the upward bent pipe connected thereto, but also has a vibration damping effect, which can reduce the adverse effects of vibrations caused by wind force, earthquake or other external factors on the upper header and the entire system. By setting both the upward bent pipe and the downward bent pipe in a U-shape, it can reduce the turbulence phenomenon when the molten salt fluid passes through the upward bent pipe and the downward bent pipe, make the molten salt fluid flow more smoothly, reduce the speed change of the molten salt fluid at the turning point, reduce the impact and wear on the pipe walls of the upward bent pipe and the downward bent pipe, and extend the service life of the upward bent pipe and the downward bent pipe.

[0024] 6. An anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system of the present utility model, by arranging a heat insulation layer on the outer walls of the first outer shell, the second outer shell and the heat absorption tube screen, it can significantly reduce the loss of heat energy from the outer shell to the surrounding environment, so as to avoid the freezing and blocking phenomenon of the molten salt fluid in the upper bent pipe, the heat absorption tube screen and the lower bent pipe. Brief Description of the Drawings

[0025] Figure 1 It is a schematic diagram of the overall sectional structure of an anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system of the present utility model;

[0026] Figure 2 It is a schematic side view of the overall structure of the lower bent pipe and the lower header of an anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system of the present utility model;

[0027] Figure 3 It is a schematic side view of the overall structure of an enlarged diameter joint of an anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system of the present utility model.

[0028]

Description of the Reference Numerals

[0029] 1: Auxiliary heat mirror field; 2: Heat absorber body; 21: Lower bent pipe; 211: First pipe section; 212: Second pipe section; 22: First outer shell; 23: Second outer shell; 24: Heat absorption tube screen; 25: Upper header; 26: Lower header; 27: Upper bent pipe; 3: Plane mirror; 4: Enlarged diameter joint; 41: First connection section; 42: Enlarged diameter section; 43: Second connection section; 5: Electric tracing device; 6: Elastic member. Detailed Embodiments

[0030] In order to better understand the above technical solutions, the exemplary embodiments of the present utility model will be described in more detail with reference to the accompanying drawings. Although the exemplary embodiments of the present utility model are shown in the drawings, it should be understood that the present utility model can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present utility model and to fully convey the scope of the present utility model to those skilled in the art.

[0031] Embodiment 1

[0032] As Figures 1 - 3 shown, an anti-freezing and anti-blocking heat absorber for a molten salt tower type solar thermal power station system in this embodiment, the molten salt tower type solar thermal power station system includes an auxiliary heat mirror field 1 installed on the ground, and the anti-freezing and anti-blocking heat absorber includes a heat absorber body 2 and a plane mirror 3.

[0033] Specifically, as Figure 1As shown in the figure, the heat absorber body 2 includes a downward-bent pipe 21 and a heat absorption tube screen 24. The downward-bent pipe 21 is installed inside the bottom of the heat absorber body 2. The heat absorption tube screen 24 is located above the downward-bent pipe 21, and the outlet end of the heat absorption tube screen 24 is communicated with the inlet end of the downward-bent pipe 21. The planar mirror 3 is installed on the bottom wall of the top of the heat absorber body 2 facing the outside world and is located above the auxiliary heat mirror field 1 so that it can receive the sunlight projected by the auxiliary heat mirror field 1. The planar mirror 3 can reflect the projected sunlight to the position of the heat absorption tube screen 24 close to the downward-bent pipe 21, that is, from the connection of the heat absorption tube screen 24 and the downward-bent pipe 21 upward to the 0-1 / 5 position of the heat absorption tube screen 24, so that the heat absorption tube screen 24 can absorb the heat of the sunlight and transfer the heat to the downward-bent pipe 21 to melt the crystallized molten salt frozen in the downward-bent pipe 21. By setting the auxiliary heat mirror field 1 and arranging the planar mirror 3 on the bottom wall of the top of the heat absorber body 2, when the molten salt in the downward-bent pipe 21 is blocked by freezing, since the position of the downward-bent pipe 21 is usually a position where sunlight cannot shine, that is, a spot-free area, the auxiliary heat mirror field 1 can reflect the sunlight projected on it to the planar mirror 3, and then through the reflection of the planar mirror 3, the sunlight is reflected to the downward-bent pipe 21, so as to realize absorbing the heat of the sunlight through the heat absorption tube screen 24 and transferring the heat of the sunlight to the downward-bent pipe 21 to melt the crystallized molten salt frozen in the downward-bent pipe 21 by the heat of the sunlight, thus avoiding the phenomenon of freezing of the molten salt in the downward-bent pipe 21, further avoiding affecting the flow of the molten salt, and thus avoiding affecting the power generation.

[0034] Among them, the auxiliary heat mirror field 1 is composed of multiple mirrors that can rotate with the position of the sun. It can track the position of the sun, that is, the sun rises in the east and sets in the west, and the mirrors of the auxiliary heat mirror field 1 rotate with the rising and setting of the sun, always aiming at the sun, so that the sunlight always shines on the mirrors, so that the mirrors of the auxiliary heat mirror field 1 can project the sunlight shining on the mirrors to the planar mirror 3, and then realize that the planar mirror 3 can irradiate the sunlight on the heat absorption tube screen 24, so that the heat absorption tube screen 24 can absorb the heat of the sunlight, and then realize that the heat absorption tube screen 24 transfers the heat to the downward-bent pipe 21 to melt the molten salt frozen in the downward-bent pipe 21. Among the mirrors in the auxiliary heat mirror field 1, the area range of a single mirror is 0.3m 2 -1.5m 2, so that a single mirror can project sufficient sunlight onto the planar mirror 3. Among them, the angle between the mirror and the horizontal plane is determined according to the local location conditions and the position of the sun. The range of the incident angle at which the auxiliary mirror field 1 projects sunlight onto the planar mirror 3 and the reflection angle at which the planar mirror 3 reflects sunlight onto the heat absorption tube screen 24 is 5° - 20°, so that the heat absorption tube screen 24 can absorb sufficient energy of sunlight when absorbing the heat of sunlight, and convert the energy into heat, so that the temperature of the heat absorption tube screen 24 itself reaches above 260 °C, so as to realize that when the heat of the heat absorption tube screen 24 is transferred to the downward bend 21, the molten salt frozen and blocked in the downward bend 21 can be melted, ensuring that the crystalline molten salt absorbs sufficient heat and melts. Preferably, the planar mirror 3 is composed of multiple plane mirrors, and the multiple plane mirrors enclose a circular ring shape, and the top of the heat absorption tube screen 24 is located inside the circular ring, so that each mirror in the auxiliary mirror field 1 can project sunlight onto the multiple plane mirrors, so that the energy of the sunlight reflected by the planar mirror 3 can be more transferred to the heat absorption tube screen 24, improving the heat transfer efficiency. Among them, the number of plane mirrors is usually a multiple of 4, such as 4 2 , 4 3 , 4 4 and so on, so that the multiple plane mirrors can be arranged more evenly, and the effect of the planar mirror 3 reflecting sunlight is better. The area range of each plane mirror is 0.15m 2 -0.5m 2 , to ensure that each plane mirror is arranged more evenly. Here, it should be noted that the planar mirror 3 can also be replaced with a reflective coating to reflect the sunlight projected by the auxiliary mirror field 1.

[0035] Further, the heat absorber body 2 further includes a first outer shell 22 and a second outer shell 23. The first outer shell 22 is located above the second outer shell 23, and the heat absorption tube screen 24 is located between the first outer shell 22 and the second outer shell 23. The planar mirror 3 is installed on the bottom wall of the first outer shell 22. The inner wall of the planar mirror 3 is in contact with the outer wall of the heat absorption tube screen 24, and the outer wall of the planar mirror 3 is flush with the outer side wall of the first outer shell 22. The downward bent pipe 21 is installed inside the second outer shell 23. One end of the downward bent pipe 21 is communicated with the heat absorption tube screen 24, and the other end is communicated with the lower header 26 inside the second outer shell 23. The lower header 26 is installed on the inner bottom wall of the second outer shell 23. The planar mirror 3 can reflect the sunlight irradiated on the auxiliary heat mirror field 1 to the position of the heat absorption tube screen 24 near the downward bent pipe 21. By installing the planar mirror 3 on the bottom wall of the first outer shell 22, and the inner wall of the planar mirror 3 is in contact with the outer wall of the heat absorption tube screen 24, and the outer wall of the planar mirror 3 is flush with the outer side wall of the first outer shell 22, it can enable the planar mirror 3 to receive the sunlight projected from the auxiliary heat mirror field 1 to the greatest extent, so that the planar mirror 3 can irradiate more heat of the sunlight onto the heat absorption tube screen 24, so as to transfer more heat of the sunlight from the heat absorption tube screen 24 to the downward bent pipe 21, improving the heat absorption efficiency of the heat absorption tube screen 24 and the downward bent pipe 21, so that the crystallized molten salt frozen in the downward bent pipe 21 can be quickly melted, so as not to affect the power generation. Preferably, heat insulation layers are provided on the outer walls of the first outer shell 22, the second outer shell 23 and the heat absorption tube screen 24, which can significantly reduce the loss of heat energy through the outer shell to the surrounding environment, so as to avoid the freezing phenomenon of the molten salt fluid in the upward bent pipe 27, the heat absorption tube screen 24 and the downward bent pipe 21.

[0036] Further, the downward bent pipe 21 includes a first pipe section 211 and a second pipe section 212. One end of the first pipe section 211 is communicated with the heat absorption tube screen 24, and the other end is communicated with the second pipe section 212 through an expansion joint 4. The diameter of the end of the expansion joint 4 connected to the first pipe section 211 is smaller than the diameter of the end of the expansion joint 4 connected to the second pipe section 212. For example, the diameter of the first pipe section 211 is 30 mm, and the diameter of the second pipe section 212 is 45 mm, which can enable the molten salt fluid located in the first pipe section 211 to enter the second pipe section 212 more smoothly and with a larger flow rate, improving the power generation capacity.

[0037] Further, the diameter-expanding joint 4 includes a first connection section 41, a diameter-expanding section 42, and a second connection section 43 that are connected in sequence. The diameter-expanding section 42 can make the transition of the molten salt fluid from the first connection section 41 to the second connection section 43 smoother, reducing the resistance when the molten salt fluid passes through the diameter-expanding joint 4. The ratio range of the pipe diameter of the second connection section 43 to the pipe diameter of the first connection section 41 is 1.2 - 1.6, which can reduce the pressure drop when the fluid passes through the joint, reduce the turbulence phenomenon, and make the molten salt fluid flow more smoothly. Preferably, the length ranges of both the first connection section 41 and the second connection section 43 are 10 mm - 50 mm, which can make the connection between the first connection section 41 and the second connection section 43 more stable when they are respectively connected to the first pipe section 211 and the second pipe section 212.

[0038] Further, the anti-freezing and plugging heat absorber further includes an electric tracing device 5. The heat absorption tube screen 24 includes a plurality of heat absorption tubes, and a plurality of downward bends 21 are provided. The plurality of downward bends 21 are in one-to-one correspondence and communicate with the plurality of heat absorption tubes. The electric tracing device 5 is sleeved on the outer walls of the plurality of downward bends 21 through wire meshes in one-to-one correspondence, and is used to assist in heating the molten salt in the plurality of downward bends 21. In order to ensure that the molten salt in the downward bends 21 does not freeze and plug in cloudy days or when the temperature is too cold, the downward bends 21 can be heated through the electric tracing device 5, ensuring that the molten salt remains liquid under any weather conditions, avoiding the blockage problem caused by freezing, and improving the overall reliability of the system.

[0039] Further, the heat absorber body 2 further includes an elastic member 6. An upper header 25 is installed in the first outer shell 22. The top of the upper header 25 is connected to the top wall inside the first outer shell 22. The bottom of the upper header 25 communicates with the heat absorption tube screen 24 through a plurality of upward bends 27. The bottom of the elastic member 6 passes through the first outer shell 22 and is connected to the upper header 25. The elastic member 6 can not only provide a certain displacement space for the upper header 25 during thermal expansion, thereby reducing the thermal stress caused by temperature changes and avoiding damage to the upper header 25 and the upward bends 27 connected thereto, but also has a vibration damping effect, which can reduce the adverse effects of vibrations caused by wind, earthquake or other external factors on the upper header 25 and the entire system. Preferably, both the upward bends 27 and the downward bends 21 are in a U-shaped configuration arranged horizontally, which can reduce the turbulence phenomenon when the molten salt fluid passes through the upward bends 27 and the downward bends 21, make the molten salt fluid flow more smoothly, reduce the speed change of the molten salt fluid at the turning points, and reduce the impact and wear on the pipe walls of the upward bends 27 and the downward bends 21, extending the service life of the upward bends 27 and the downward bends 21.

[0040] Embodiment 2

[0041] The anti-freezing and plugging working principle of the anti-freezing and plugging heat absorber for a molten salt tower type solar thermal power station system in this embodiment is as follows:

[0042] First, a plurality of mirrors in the auxiliary heat mirror field 1 are evenly distributed and installed on the ground. A plurality of plane mirrors in the plane mirror 3 are installed on the bottom wall of the top of the heat absorber according to a multiple of 4 and are arranged in a circular ring, so that the top of the heat absorption tube screen 24 is placed inside the plane mirror 3 in the circular ring, and moreover, the outer wall of the heat absorption tube screen 24 is attached to the inner wall of the plane mirror 3. When the weather is relatively cold, and generally, the position of the downward bent pipe 21 is a place where sunlight cannot shine, so that the molten salt flowing in the downward bent pipe 21 reaches the freezing point, and crystalline molten salt appears. The crystalline molten salt gradually accumulates, resulting in the phenomenon that the downward bent pipe 21 is blocked by freezing. At this time, it is necessary to turn on the auxiliary heat mirror field 1. The sunlight shines on each mirror in the auxiliary heat mirror field 1, and each mirror projects the sunlight onto a plurality of plane mirrors in the plane mirror 3. The plurality of plane mirrors reflect the sunlight to the position of the heat absorption tube screen 24 close to the downward bent pipe 21, ensuring that the incident angle and the reflection angle are between 5° and 20°. Thus, the heat absorption tube screen 24 absorbs the heat of the sunlight and transfers the heat to the position of the downward bent pipe 21. The crystalline molten salt in the downward bent pipe 21 absorbs this heat and gradually melts, realizing the melting of the crystalline molten salt blocked in the downward bent pipe 21.

[0043] After the crystalline molten salt in the downward bent pipe 21 is melted and unblocked, turn off the auxiliary heat mirror field 1.

[0044] In the description of the present invention, it should be understood that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, the meaning of "a plurality of" is two or more unless otherwise specifically defined.

[0045] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium; it may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] In the present utility model, unless otherwise clearly defined and limited, a first feature being "on" or "under" a second feature may mean that the first and second features are in direct contact, or that the first and second features are indirectly in contact via an intermediate medium. Moreover, a first feature being "above", "over" and "on top of" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. A first feature being "under", "below" and "beneath" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature.

[0047] In the description of this specification, the descriptions of terms such as "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples", etc., mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples.

[0048] Although the embodiments of the present utility model have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present utility model. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present utility model.

Claims

1. An anti-freezing heat absorber for a molten salt tower type solar thermal power station system, the molten salt tower type solar thermal power station system comprising an auxiliary heat mirror field (1) installed on the ground, characterized in that: The anti-freezing heat absorber comprises a heat absorber body (2) and a plane reflector (3); The heat absorber body (2) comprises a lower curved pipe (21) and a heat absorbing tube panel (24), wherein the lower curved pipe (21) is installed inside the bottom of the heat absorber body (2), and the heat absorbing tube panel (24) is located above the lower curved pipe (21), and the outlet end of the heat absorbing tube panel (24) is connected to the inlet end of the lower curved pipe (21); The plane reflector (3) is mounted on the bottom wall of the top of the absorber body (2) facing the outside world, and is located above the auxiliary heat mirror field (1) so that it can receive the sunlight projected by the auxiliary heat mirror field (1). The plane reflector (3) can reflect the projected sunlight to the position of the absorber tube panel (24) close to the lower bend tube (21), so that the absorber tube panel (24) can absorb the heat of the sunlight and transfer the heat to the lower bend tube (21) to melt the crystallized molten salt frozen in the lower bend tube (21).

2. The anti-freezing heat absorber for use in a molten salt tower solar thermal power station system according to claim 1, characterized in that: The heat absorber body (2) further comprises a first shell (22) and a second shell (23); The first shell (22) is located above the second shell (23) and the heat absorbing tube panel (24) is located between the first shell (22) and the second shell (23); The plane reflector (3) is mounted on the bottom wall of the first shell (22), the inner wall of the plane reflector (3) is in contact with the outer wall of the heat absorbing tube panel (24), and the outer wall of the plane reflector (3) is flush with the outer wall of the first shell (22); The lower curved pipe (21) is installed inside the second shell (23), one end of the lower curved pipe (21) is connected to the heat absorbing tube panel (24), and the other end is connected to the lower header (26) in the second shell (23), and the lower header (26) is installed on the inner bottom wall of the second shell (23); The plane reflector (3) is capable of reflecting the sunlight irradiated on the auxiliary heat mirror field (1) to a position of the heat absorbing tube panel (24) close to the lower bent tube (21).

3. The anti-freezing heat absorber for use in a molten salt tower solar thermal power station system according to claim 1, characterized in that: The lower curved pipe (21) comprises a first pipe section (211) and a second pipe section (212); One end of the first pipe section (211) is connected to the heat absorbing tube panel (24), and the other end is connected to the second pipe section (212) via a diameter expansion joint (4); the pipe diameter of the end of the diameter expansion joint (4) connected to the first pipe section (211) is smaller than the pipe diameter of the end of the diameter expansion joint (4) connected to the second pipe section (212).

4. The anti-freezing heat absorber for use in a molten salt tower solar thermal power station system according to claim 3, characterized in that: The diameter expansion joint (4) comprises a first connecting section (41), a diameter expansion section (42) and a second connecting section (43) which are connected in sequence; The ratio of the diameter of the second connecting section (43) to the diameter of the first connecting section (41) is in the range of 1.2-1.

6.

5. The anti-freezing heat absorber for use in a molten salt tower solar thermal power station system according to claim 4, characterized in that: The lengths of the first connecting section (41) and the second connecting section (43) are both in the range of 10 mm to 50 mm.

6. The anti-freezing heat absorber for use in a molten salt tower solar thermal power station system according to claim 2, characterized in that: The anti-freezing heat absorber also includes an electric heating device (5); The heat absorbing tube panel (24) comprises a plurality of heat absorbing tubes, and a plurality of the lower bent tubes (21) are provided. The plurality of the lower bent tubes (21) are connected to the plurality of the heat absorbing tubes in a one-to-one correspondence. The electric heating device (5) is sleeved on the outer walls of the plurality of the lower bent tubes (21) in a one-to-one correspondence through a steel wire mesh, and is used to assist in heating the molten salt in the plurality of the lower bent tubes (21).

7. The anti-freezing heat absorber for use in a molten salt tower solar thermal power station system according to claim 2, characterized in that: The heat absorber body (2) further comprises an elastic member (6); An upper header (25) is installed in the first shell (22); the top of the upper header (25) is connected to the top wall inside the first shell (22); the bottom of the upper header (25) is connected to the heat absorbing tube panel (24) through a plurality of upper curved pipes (27); and the bottom of the elastic member (6) passes through the first shell (22) and is connected to the upper header (25).

8. The anti-freezing heat absorber for use in a molten salt tower solar thermal power station system according to claim 7, characterized in that: The upper curved pipe (27) and the lower curved pipe (21) are both arranged transversely in the shape of a Chinese character "X".

9. The anti-freezing heat absorber for use in a molten salt tower solar thermal power station system according to claim 2, characterized in that: The outer walls of the first outer shell (22), the second outer shell (23) and the heat absorbing tube panel (24) are all provided with a heat insulation layer.

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