Cooling device for hot melting lakes and ponds along project in permafrost region

Abstract

The invention relates to a cooling device for a hot melting pond along a project in a permafrost region. The cooling device comprises a plurality of floating units which are spliced in an array mode to cover the water surface of the hot melting pond and a peripheral thermal erosion exposed area and synchronously ascend and descend along with the water level. Each floating unit comprises a plurality of refrigeration reflection units, and the plurality of refrigeration reflection units are embedded on the floating unit in an array mode; each floating unit is composed of a prefabricated floating carrier provided with a groove, a one-way water stop valve is arranged at the bottom of each floating unit, and fixing round holes are formed in the four corners of each floating unit. A low-temperature-resistant rubber bushing is arranged on the inner wall of the fixed round hole; each refrigeration reflection unit is made of a plate type refrigeration pipe with a hollow structure, the interior of each refrigeration reflection unit is filled with a phase change working medium, and the sunny side is coated with an anti-radiation coating. Through a composite mechanism of'heat insulation and cooling-refrigeration reflection-evaporation heat consumption ', the temperature of hot melting lake and pond water and surrounding soil is remarkably reduced, thermal disturbance of the water and surrounding soil to surrounding and under-covered frozen soil is eliminated, and the device is suitable for plateau power-free, strong-radiation and large-temperature-difference environments.

Description

Technical Field

[0001] This invention relates to the field of treatment and prevention of diseases in permafrost engineering, and in particular to a device for cooling lakes and ponds along engineering projects in permafrost areas. Background Technology

[0004] Analysis of monitoring data on thawed lakes and surrounding soil in the Qinghai-Tibet Plateau region reveals that heat exchange between these lakes and the surrounding permafrost is the primary cause of increased soil temperature and a decrease in the permafrost's upper limit (permafrost degradation). Given that thawed lakes are often located along roads within engineering corridors, and that the stability of permafrost engineering foundations depends on the thermal stability of the permafrost, currently, technologies to effectively eliminate thermal erosion from thawed lakes, significantly reduce their temperature, and promote positive permafrost development around them, thereby stabilizing permafrost engineering projects, are still lacking.

[0005] In existing technologies, most domestic patents focus on a single mechanism of "passive heat insulation + localized cooling." For example, patent CN202410548820.8 (A structure for eliminating the impact of melting lakes on roadbed stability) attempts to eliminate the impact of melting lakes on roadbed stability using only lightweight concrete walls, heat pipes inserted into frozen soil, and reflective materials covering the soil surface. However, because concrete itself absorbs heat and is a good conductor of heat, the condensation section of the heat pipes is exposed to the air, and the reflective material only covers the soil between the concrete wall and the foundation, it cannot solve the problem of long-term heat accumulation in large areas of lakebed water. Furthermore, lightweight concrete structures are highly susceptible to freeze-thaw damage in the harsh freeze-thaw environment of high-altitude areas, allowing a large amount of external heat to escape. Entering the permafrost through the retaining wall further promotes the melting and degradation of the permafrost, resulting in poor adaptability of the structure to the plateau. Patent CN202010191348.9 (Distributed Solar and Wind Power Plateau Permafrost Melting Lake Floating Device, System and Working Method) is submerged below the surface of the melting lake. It relies on solar and wind energy to control the temperature of the stored water in the melting lake by changing the shape of the sphere and the shape of the shape-memory alloy and colliding with each other. However, this invention cannot eliminate the influence of heat input such as solar radiation and precipitation on the development of the melting lake. Moreover, after the lake water freezes in winter, the entire system is in a frozen and fixed state and loses its cooling function.

[0006] Technologies developed by countries like Canada and Russia for managing Arctic permafrost regions often focus on "material optimization." For example, patent CA20231012345 (Arctic Permafrost Lake Cooling System) uses fluorocarbon polymer floats and aluminum reflective films. While this improves UV resistance and low-temperature performance, it only achieves passive cooling by reflecting solar radiation and does not include a phase-change cooling unit, making it unable to cool deep water. Furthermore, the floats are joined together with metal connectors, which are prone to breakage due to thermal expansion and contraction during freeze-thaw cycles. It also lacks an adaptation design for the complex environment of high-altitude areas (strong radiation, large temperature differences, and water level fluctuations).

[0007] Therefore, how to eliminate the thermal effects of thawed lakes and ponds along the Qinghai-Tibet Plateau permafrost engineering route, block the heat exchange between thawed lakes and ponds and the surrounding soil, thereby curbing permafrost degradation and thermal erosion and maintaining the long-term safety and stable operation of permafrost engineering projects, is an urgent problem to be solved in the field of permafrost engineering disease prevention and control. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a thermal erosion control device for cooling lakes and ponds along engineering routes in permafrost areas with good thermal erosion control effect and strong adaptability to plateau permafrost environment.

[0009] To address the aforementioned problems, the present invention provides a cooling device for thermally thawed lakes and ponds along engineering routes in permafrost regions. The device comprises multiple floating units arranged in an array, covering the surface of the thermally thawed lakes and ponds and surrounding exposed areas affected by thermal erosion, and rising and falling synchronously with the water level. Each floating unit includes multiple cooling and reflecting units, which are embedded in the floating unit in an array. Each floating unit consists of a prefabricated floating carrier with grooves, a one-way stop valve at its bottom, and fixed circular holes at its four corners. The inner wall of the fixed circular holes is fitted with a low-temperature resistant rubber bushing. Each cooling and reflecting unit is made of a plate-shaped cooling tube with a hollow structure, filled with a phase change working fluid, and coated with an anti-radiation coating on its sun-facing side.

[0010] Multiple floating units are spliced ​​together using nylon ropes through the array of fixed circular holes, and their edges are fixed to the lake shore with galvanized anchor chains; the nylon ropes are nylon 66 ropes containing UV-531 anti-ultraviolet agent, and their breaking strength is ≥15kN; the surface of the galvanized anchor chains is coated with polytetrafluoroethylene.

[0011] The groove is 15-20cm deep, and a water-permeable hole is provided at the bottom of the groove; the one-way stop valve is provided in the water-permeable hole.

[0012] The floating carrier is made of closed-cell rigid polyurethane foam with a thermal conductivity ≤0.025W / (m・K), a volumetric water absorption rate ≤1%, and a unit area of ​​0.25~1m². 2 .

[0013] The Shore hardness of the rubber bushing is 50~70HA.

[0014] The plate-shaped refrigeration tube has through holes arranged in an array along its length; the through holes are filled with a phase change working fluid; the phase change working fluid is a mixture of liquid ammonia and anhydrous ethanol in a mass ratio of 3:1, and the filling degree of the phase change working fluid is 60%~90%.

[0015] The portion of the cooling reflective unit embedded above the floating unit is inclined, and the sun-facing surface is coated with the anti-radiation coating; the anti-radiation coating is a polyimide-based reflective coating with a solar reflectivity ≥85%; the portion embedded below the floating unit is bent and then attached to the bottom surface of the floating unit and immersed in the lake water, and the attached area accounts for 30%~50% of the total area of ​​the plate-shaped cooling pipe.

[0016] The portion of the cooling reflective unit embedded in the floating unit is inclined at a 45° angle to the horizontal plane, and the length of this inclined section is 30~50cm, with part of it submerged in the water within the groove.

[0017] The horizontal section of the cooled reflective unit, which is embedded below the floating unit, is bent and firmly bonded to the bottom of the floating unit with epoxy adhesive that is resistant to low temperatures of -40℃ to 60℃, with a bonding strength ≥5MPa.

[0018] The floating units are laid at a density of 1.2~1.5 units / m² in the thermally eroded and exposed areas around the hot-melt lake. 2 Furthermore, the bottom of the floating unit in this area is bonded with a layer of thermal insulation cotton with a thickness of 5~10cm and a thermal conductivity of ≤0.03W / (m・K).

[0019] Compared with the prior art, the present invention has the following advantages: 1. High efficiency in controlling thermal erosion in lakes and ponds: This invention combines a triple mechanism of "heat insulation and cooling - evaporation and heat dissipation". Through the passive heat insulation of the floating unit, the evaporation and heat dissipation of the water in the groove, and the active phase change cooling of the evaporation and solar radiation reflection of the evaporation and reflection unit, it is significantly superior to the existing single mechanism technology (simple heat insulation floating bed can only reduce the surface water temperature by 2~3℃). It can effectively eliminate the thermal erosion of the surrounding frozen soil by the thermal melting lake and pond, and prevent and control the incubation and development of frozen soil engineering diseases.

[0020] 2. Strong adaptability to high-altitude environments: All components in this invention are made of materials that are resistant to low temperatures, UV radiation, and corrosion. The closed-cell polyurethane foam of the floating unit can resist strong UV aging at high altitudes. The nylon rope containing UV-531 and the polytetrafluoroethylene coated anchor chain can withstand the corrosive environment of high altitudes for a long time. The 6061 aluminum alloy cooling pipe and the low-temperature resistant epoxy adhesive can adapt to extreme low temperatures below -40°C. Moreover, the device does not require electric drive and relies entirely on natural energy (evaporation, phase change, solar energy reflection) to operate. It is suitable for the conditions of power shortage and difficulty in manual maintenance in remote high-altitude areas and can achieve continuous operation for many years.

[0021] 3. Excellent convenience and economy: The area of ​​a single floating unit in this invention is small (0.25~1m²). 2 This allows for stacked transport, reducing transportation costs by over 40% compared to transporting large floating bodies; it uses nylon rope splicing and anchor chain fixing, requiring no large equipment for on-site assembly, and can be completed by 2-3 people for a 1000m section. 2 The device is installed in lakes and ponds; after installation, no manual maintenance is required, which can save a lot of operation and maintenance costs every year and significantly reduce the cost of engineering treatment.

[0022] 4. Wide range of applications: This invention is not only applicable to thermal thaw lakes and ponds along the Qinghai-Tibet Plateau permafrost engineering route, but its low-temperature resistant design (applicable to temperatures from -60℃ to 20℃) can also be extended to similar thermal thaw disaster management in the Arctic permafrost region and the Northeast permafrost region. At the same time, it is applicable to lake and pond environments with different water level fluctuations (0.5~2m), and has good universality. Attached Figure Description

[0023] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0024] Figure 1 This is a schematic diagram of the structure of the present invention.

[0025] Figure 2 This is a top view of the floating unit in this invention.

[0026] Figure 3 This is a side view of the floating unit in this invention.

[0027] Figure 4 This is a cross-sectional view of the floating unit in this invention.

[0028] Figure 5 This is a front view of the cooling and reflecting unit structure in this invention.

[0029] Figure 6 This is a left view of the cooling and reflecting unit structure in this invention.

[0030] Figure 7 This is a right view of the cooling and reflecting unit structure in this invention.

[0031] Figure 8 This is a cross-sectional view of the cooling and reflecting unit AA in this invention.

[0032] In the figure: 1—floating unit; 101—groove; 102—fixed round hole; 103—one-way stop valve; 2—cooling reflection unit; 201—plate-shaped cooling pipe; 202—anti-radiation coating; 203—through hole. Detailed Implementation

[0033] like Figures 1-8 As shown, a cooling device for thermally thawed lakes and ponds along engineering projects in permafrost regions is disclosed. The device comprises multiple floating units 1 arranged in an array to cover the surface of the thermally thawed lakes and ponds and the surrounding exposed areas of thermal erosion, and which rise and fall synchronously with the water level. Each floating unit 1 contains multiple cooling and reflecting units 2, which are embedded in the floating unit 1 in an array. Each floating unit 1 consists of a prefabricated floating carrier with grooves 101, a one-way stop valve 103 at the bottom, and fixed round holes 102 at the four corners. The inner wall of the fixed round holes 102 is provided with a low-temperature resistant rubber bushing. Each cooling and reflecting unit 2 is made of a plate-shaped cooling tube 201 with a hollow structure, filled with a phase change working fluid to achieve phase change heat transfer and cooling, and coated with an anti-radiation coating 202 on the sun-facing side to achieve solar radiation reflection.

[0034] The floating units 1 are constructed by assembling multiple floating units using nylon ropes connected in an array through fixed circular holes 102, with their edges secured to the lake shore using galvanized anchor chains. The nylon ropes are nylon 66 ropes containing UV-531, with a tensile strength ≥15kN, capable of withstanding the pulling force of strong winds at high altitudes on the floating array. The galvanized anchor chains are coated with polytetrafluoroethylene (PTFE) to improve their corrosion resistance, extend their service life, and prevent the floating array from drifting due to anchor chain corrosion.

[0035] The groove 101 has a depth of 15-20cm. This depth design ensures that sufficient water is stored in the groove 101 to meet the evaporation heat demand, while preventing the center of gravity of the float from shifting due to excessive water accumulation, thus ensuring the stability of the float. The bottom of the groove 101 is provided with a water-permeable hole (2-3mm in diameter); a one-way stop valve 103 is installed in the water-permeable hole.

[0036] The groove 101 is used to store water to achieve evaporation heat dissipation and to provide a condensation section for cooling the refrigeration reflector unit 2.

[0037] The one-way stop valve 103 is used to regulate the water level in the groove 101 so that excess water can be discharged when the water level in the groove 101 rises, preventing water from overflowing from the groove 101. Simultaneously, when the water depth in the groove 101 drops to less than 1 cm due to heat evaporation, the one-way stop valve 103 opens to replenish water into the groove 101 from external lake water, thus maintaining the basic water volume in the groove 101. Specifically, when the water level in the groove 101 drops to a level insufficient to submerge the bottom of the inclined section of the cold reflector unit 2 due to heat evaporation, the one-way stop valve 103 opens, replenishing water into the groove 101 from the thermally melted lake pond under the pressure difference between the water level outside and inside the groove 101. When the water level in the groove 101 rises to the basic water level, the one-way stop valve 103 automatically closes, maintaining the basic water volume in the groove and ensuring the continuous operation of the evaporation heat dissipation mechanism.

[0038] The floating carrier is made of closed-cell rigid polyurethane foam with a thermal conductivity ≤0.025W / (m・K), which effectively blocks the transfer of atmospheric heat to the lake water, achieving passive insulation. Its volumetric water absorption rate is ≤1%, preventing the float from sinking due to increased weight from water absorption and ensuring long-term buoyancy. The unit area is 0.25~1m². 2 It is convenient for long-distance transportation (it can be stacked), and can be flexibly spliced ​​according to the shape of the lake or pond, adapting to thermal fusion lakes and ponds of different sizes.

[0039] The rubber bushing has a Shore hardness of 50~70HA to adapt to the temperature difference of freeze-thaw cycles from -40℃ to 20℃, and to prevent the fixed round hole 102 from being damaged due to material shrinkage and expansion during repeated freeze-thaw cycles, thus ensuring the long-term stability of the spliced ​​structure.

[0040] The plate-type refrigeration tube 201 has through holes 203 with a diameter of 5-8 mm arranged in an array along its length. The through holes 203 are filled with a phase change working fluid, which is a mixture of liquid ammonia and anhydrous ethanol at a mass ratio of 3:1 (g / g). The filling degree of the phase change working fluid is 60%-90%, providing sufficient space for vaporization and ensuring adequate circulation, thus achieving efficient phase change heat transfer in the range of -60℃ to 0℃.

[0041] The plate-type refrigerant tube 201 is made of 6061 aluminum alloy with a wall thickness of 1-2 mm. This material combines high thermal conductivity (approximately 167 W / (m·K)) with good low-temperature toughness, making it suitable for extreme low-temperature environments below -40°C at high altitudes. The through-hole design 203 increases the contact area between the working fluid and the tube wall, improving phase change heat transfer efficiency. The freezing point of the mixed working fluid is as low as -60°C, allowing it to remain liquid in high-altitude low-temperature environments and preventing freezing that could lead to refrigeration failure.

[0042] The portion of the cooling reflective unit 2 embedded in the floating unit 1 is inclined, and its sun-facing surface is coated with an anti-radiation coating 202. The anti-radiation coating 202 is a polyimide-based reflective coating with a solar reflectivity of ≥85%, which can significantly reduce the heating of the condensation section by solar radiation. The portion embedded below the floating unit 1 is bent and attached to the bottom surface of the floating unit 1 and immersed in the lake water. The contact area accounts for 30% to 50% of the total area of ​​the plate-type cooling pipe 201. This contact area design can maximize the contact area between the evaporation section and the lake water while ensuring the buoyancy of the floating body, thereby improving the heat absorption efficiency.

[0043] The portion of the cooling reflector unit 2 embedded in the floating unit 1 is inclined at a 45° angle to the horizontal plane, and the length of this inclined section is 30~50cm, partially submerged in the water within the groove 101. This partial submersion of the inclined section in the water within the groove 101 allows for rapid heat removal from the condensation section through water evaporation, further reducing the temperature of the condensation section, increasing the temperature difference between the condensation and evaporation sections, and accelerating the circulation of the working fluid.

[0044] The horizontal section of the refrigeration reflector unit 2, which is embedded under the floating unit 1, is bent and firmly bonded to the bottom of the floating unit 1 with epoxy adhesive that is resistant to low temperatures of -40℃ to 60℃. The bonding strength is ≥5MPa, which can ensure that the refrigeration reflector unit 2 will not fall off under freeze-thaw cycles and lake wave impacts, thus ensuring the structural integrity of the device.

[0045] The density of floating unit 1 in the thermally eroded and exposed areas around the hot-melt lake is 1.2~1.5 units / m. 2 Furthermore, the bottom of floating unit 1 in this area is bonded with an insulation layer of 5-10cm thickness and a thermal conductivity of ≤0.03W / (m・K). The insulation layer can block the transfer of surface heat to the underground permafrost, prevent the surrounding exposed soil from absorbing solar radiation heat and thus accelerate the thawing of the permafrost, achieving coordinated cooling of the lake and the surrounding soil.

[0046] This invention achieves the cooling of hot-melt lakes and ponds and the control of thermal erosion of the surrounding frozen soil through the combined effects of the heat insulation of the floating unit 1, the evaporation heat dissipation of the groove 101, and the phase change cooling and radiation reflection of the cooling reflection unit 2.

[0047] The steps for manufacturing and deploying this device are as follows: 1. Prefabricated cooling reflector unit In the factory, 6061 aluminum alloy sheets are selected and processed into plate-shaped refrigeration tubes 201 with a wall thickness of 1.5mm and an internal through hole 203 with a diameter of 6mm. These tubes are then cut into strips with a length of 70cm. Liquid ammonia and anhydrous ethanol are mixed at a mass ratio (g / g) of 3:1, and the mixed working fluid is injected into the through hole 203 with a filling degree controlled at 75%. Subsequently, the two ends of the tube are sealed by laser welding to complete the encapsulation of the working fluid. Polyimide-based anti-radiation coating is sprayed on the sun-facing side of the tube to form an anti-radiation coating 202, ensuring a solar reflectivity of ≥85%, thus obtaining the refrigeration reflective unit 2.

[0048] Floating unit processing Floating unit 1 was prefabricated using closed-cell rigid polyurethane foam (thermal conductivity 0.023 W / (m・K), volumetric water absorption 0.8%), with a unit area of ​​0.5m × 0.5m (0.25m). 2 A groove 101 with a depth of 18cm is made on the unit; a water-permeable hole with a diameter of 2.5mm is drilled at the bottom of the groove 101, and a one-way stop valve 103 is installed; fixing round holes 102 are made at the four corners of the floating unit 1, and a low-temperature resistant rubber bushing with a Shore hardness of 60HA is pasted on the inner wall of the round hole; according to the size of the cooling reflective unit 2, two rows and two columns of vertical holes are made in the groove 101 of the floating unit 1, with a hole spacing of 15cm.

[0049] Unit assembly Insert the cooling reflector unit 2 into the opening of the floating unit 1, leaving a 40cm length on one side of the groove 101. Bend this section at the bottom of the groove so that it forms a 45° angle with the horizontal plane, ensuring that 10cm of it is submerged in the water in the groove. At the bottom of the floating unit 1, bend the remaining 30cm length of the cooling reflector unit 2 horizontally at a 90° angle, leaving an 8cm horizontal section, and then bend it vertically downwards. Apply low-temperature resistant epoxy adhesive to the side of the horizontal section facing the bottom of the floating unit 1 and bond it to the bottom of the floating unit 1. After curing, test the bonding strength to ensure it is ≥5MPa. Use silicone sealant to seal the gap between the opening and the cooling reflector unit to prevent water leakage from the groove 101.

[0050] On-site setup Based on the area of ​​the thermal melting lake (in 1000m²) 2 For example, prepare 4000 assembled floating units 1; use nylon 66 ropes containing UV-531 (breaking strength 18kN) to splice the floating units 1 into an array of floating beds through fixed round holes 102; drive anti-corrosion wooden piles into the lake shore, and use galvanized anchor chains with polytetrafluoroethylene coating to fix the edges of the floating beds to the anti-corrosion wooden piles to ensure that the floating beds can rise and fall with the water level; for the thermally eroded exposed areas around the lake (area 500m²) 2 ), at 1.3 pieces / m 2The floating units 1 are laid at a certain density, and an 8cm thick layer of thermal insulation cotton is bonded to the bottom of the floating units in this area to complete the deployment of the entire device.

[0051] [Working Principle] This device achieves thermal erosion control of hot-melt lakes and ponds through a composite mechanism of "heat insulation and cooling - cooling reflection - evaporation heat dissipation". The specific process is as follows: Thermal insulation and cooling: The closed-cell rigid polyurethane foam of floating unit 1 has a low thermal conductivity (≤0.025W / (m・K)) and excellent thermal insulation performance. After being arrayed and spread across the lake surface, it can block the transfer of atmospheric heat to the lake water and reduce the input of external heat sources. The insulation cotton layer at the bottom of the floating unit in the surrounding exposed area can block the transfer of solar radiation heat from the ground surface to the underground permafrost and prevent further degradation of the permafrost.

[0052] Evaporation heat dissipation process: The groove 101 of the floating unit 1 maintains the basic water volume through the one-way stop valve 103. The water in the groove 101 continues to evaporate in the high-evaporation environment of the plateau. The evaporation process consumes a large amount of heat (the latent heat of vaporization of water is about 2260kJ / kg), which can directly reduce the lake surface temperature. At the same time, the water in the groove 101 comes into contact with the condensation section (inclined submerged part) of the cooling reflection unit 2. Through convection heat transfer, the heat of the condensation section is quickly removed, reducing the temperature of the condensation section.

[0053] Cooling and Reflection Process: The evaporation section (the bend submerged in the lake water) of cooling and reflecting unit 2 absorbs heat from the lake water, causing the internal liquid ammonia-ethanol mixture to vaporize and form low-temperature steam. Due to the significant temperature reduction in the condensation section (tilted section) caused by the reflection of the anti-radiation coating 202 and the evaporation of the water (8-12℃ lower than the evaporation section), the steam flows rapidly to the condensation section under the action of pressure difference. In the condensation section, the steam releases the latent heat of phase change and condenses into liquid. The heat is diffused to the atmosphere through water evaporation and air convection. The condensed liquid flows back to the evaporation section under the action of gravity, completing one cooling cycle. This cycle continues, continuously transferring heat from the lake water to the atmosphere, thus cooling the lake water. At the same time, the anti-radiation coating 202 reflects more than 85% of solar radiation, reducing the solar radiation heat absorbed by the lake water and further enhancing the cooling effect.

[0054] Under the synergistic effect of the above three mechanisms, the water temperature of the thermomelting lakes and ponds continues to decrease, the heat exchange between the lakes and ponds and the surrounding permafrost is blocked, the upper limit of the permafrost gradually rises, and finally the thermal erosion of the thermomelting lakes and ponds is controlled, promoting the stability and positive development of the permafrost around the lakes and ponds, and ensuring the long-term stable operation of the permafrost project.

Claims

1. A device for cooling lakes and ponds along engineering routes in permafrost regions, characterized in that: The device includes multiple floating units (1) arranged in an array to cover the surface of the hot-melt lake and the surrounding exposed areas of thermal erosion, and which rise and fall synchronously with the water level; each floating unit (1) includes multiple cooling reflective units (2), and the multiple cooling reflective units (2) are embedded in the floating unit (1) in an array; each floating unit (1) is composed of a prefabricated floating carrier with grooves (101), and has a one-way stop valve (103) at the bottom and fixed round holes (102) at the four corners; the inner wall of the fixed round holes (102) is provided with a low-temperature resistant rubber bushing; each cooling reflective unit (2) is made of a plate-shaped cooling tube (201) with a hollow structure, filled with a phase change working fluid, and coated with an anti-radiation coating (202) on the sun-facing side.

2. The thermal thawing and pond cooling device along a permafrost engineering project as described in claim 1, characterized in that: Multiple floating units (1) are spliced ​​together by an array of nylon ropes through the fixed circular holes (102), and the edges are fixed to the lake shore with galvanized anchor chains; the nylon ropes are nylon 66 ropes containing UV-531 anti-ultraviolet agent, and their breaking strength is ≥15kN; the surface of the galvanized anchor chains is coated with polytetrafluoroethylene coating.

3. The thermal thawing and pond cooling device along the engineering route in permafrost areas as described in claim 1, characterized in that: The groove (101) has a depth of 15~20cm, and the bottom of the groove (101) is provided with a water-permeable hole; the one-way stop valve (103) is provided in the water-permeable hole.

4. The thermal thawing and pond cooling device along the engineering route in permafrost areas as described in claim 1, characterized in that: The floating carrier is made of closed-cell rigid polyurethane foam with a thermal conductivity ≤0.025W / (m・K), a volumetric water absorption rate ≤1%, and a unit area of ​​0.25~1m². 2 .

5. The thermal thawing and pond cooling device along a permafrost engineering project as described in claim 1, characterized in that: The Shore hardness of the rubber bushing is 50~70HA.

6. The thermal thawing and pond cooling device along the engineering route in permafrost areas as described in claim 1, characterized in that: The plate-shaped refrigeration tube (201) has through holes (203) arranged in an array along its length. The through holes (203) are filled with a phase change working fluid. The phase change working fluid is a mixture of liquid ammonia and anhydrous ethanol in a mass ratio of 3:1, and the filling degree of the phase change working fluid is 60%~90%.

7. The thermal thawing and pond cooling device along a permafrost engineering project as described in claim 1, characterized in that: The portion of the cooling reflective unit (2) embedded above the floating unit (1) is inclined, and the surface of the sun-facing side is coated with the anti-radiation coating (202); the anti-radiation coating (202) is a polyimide-based reflective coating with a solar reflectivity ≥85%; the portion embedded below the floating unit (1) is bent and then attached to the bottom surface of the floating unit (1) and immersed in the lake water, and the attached area accounts for 30%~50% of the total area of ​​the plate-shaped cooling pipe (201).

8. The thermal thawing and pond cooling device along the engineering route in permafrost areas as described in claim 7, characterized in that: The portion of the cooling reflective unit (2) embedded above the floating unit (1) is inclined at a 45° angle to the horizontal plane, and the length of the inclined section is 30~50cm, and it is partially submerged in the water in the groove (101).

9. A thermal thawing and pond cooling device along a permafrost engineering project as described in claim 7, characterized in that: The horizontal section of the cooling reflective unit (2) embedded under the floating unit (1) after bending is firmly bonded to the bottom of the floating unit (1) with epoxy adhesive that is resistant to low temperatures of -40℃ to 60℃, and the bonding strength is ≥5MPa.

10. A thermal thawing and pond cooling device along a permafrost engineering project as described in claim 1, characterized in that: The floating unit (1) is laid at a density of 1.2~1.5 units / m in the thermally eroded exposed area around the hot-melt lake. 2 Furthermore, the bottom of the floating unit (1) in this area is bonded with a thermal insulation cotton layer with a thickness of 5~10cm and a thermal conductivity of ≤0.03W / (m・K).

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