Graphitization kiln intensified cooling device and waste heat recovery system

Abstract

This utility model belongs to the field of graphite material production technology, and discloses an enhanced cooling device and waste heat recovery system for a graphitization kiln. The enhanced cooling device includes a circulation pipeline for the flow of heat transfer oil, a heat exchange component, a cooling component, and a supply component. The heat exchange component includes a movable heat exchange module that can be moved close to or away from the graphitization kiln. The heat exchange module has a heat exchange channel through which heat transfer oil flows to exchange heat with the graphitization kiln. The cooling component includes a coiled heat exchanger with a medium inlet and a medium outlet, used to cool the heat transfer oil. The supply component stores and processes the heat transfer oil, and supplies processed heat transfer oil to the heat exchange tubes and heat exchange modules. By delivering the heat transfer oil to the heat exchange module for heat exchange with the graphitization kiln, the cooling cycle is shortened, production efficiency is improved, and the movable heat exchange module reduces implementation difficulty.

Description

Technical Field

[0001] This utility model relates to the field of graphite material production technology, and in particular to a graphitization kiln enhanced cooling device and waste heat recovery system. Background Technology

[0002] In the operation of the graphitization kiln, electrodes are used as a heat source to efficiently heat the kiln, enabling its internal temperature to reach a peak of 3000℃. After the heating stage is completed, the cooling stage begins. Once the surface temperature has cooled to 500℃, a suction device is used to discharge the cooled insulation material or product, and this process is repeated until the discharge is complete.

[0003] Currently, two main cooling methods are used: natural cooling and fixed heat exchange equipment connected to the outside of the graphitization kiln. However, when using natural cooling, according to the current process, it takes about 8 hours to cool a 15cm thick material to below 500℃, which extends the single kiln discharge cycle to more than 20 days, severely restricting production efficiency and product output rate. When using fixed heat exchange equipment connected to the outside of the graphitization kiln, the kiln moves during the discharge process, making the implementation of the fixed heat exchange equipment difficult. In addition, whether using natural cooling or heat exchange equipment, the entire top area of ​​the graphitization kiln must be cooled before subsequent operations can proceed, greatly extending the production cycle and resulting in serious energy waste. A large amount of heat energy released during the cooling process is not effectively recovered and utilized, resulting in poor energy utilization.

[0004] In view of the above, this utility model is hereby proposed. Utility Model Content

[0005] The purpose of this utility model is to provide a graphitization kiln enhanced cooling device and waste heat recovery system, which has at least one of the following beneficial effects: shorter cooling cycle, higher production efficiency, higher energy utilization rate, and easy implementation.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] On one hand, this utility model provides an enhanced cooling device for a graphitization kiln, including a circulation pipeline for the flow of heat transfer oil, a heat exchange component and a cooling component disposed on the circulation pipeline, and a supply component connected to the circulation pipeline, wherein:

[0008] The heat exchange assembly includes a movable heat exchange module that can be close to or away from the graphitization kiln. The heat exchange module is provided with a heat exchange channel that is connected to the circulation pipeline and has a heat exchange inlet and a heat exchange outlet.

[0009] The cooling assembly includes a coil heat exchanger, which has a medium inlet for the heat transfer oil to flow into and a medium outlet for the heat transfer oil to flow out. The coil heat exchanger is used to cool the heat transfer oil.

[0010] The supply component is used for storing the heat transfer oil and supplying the heat transfer oil to the circulation pipeline.

[0011] Optionally, the heat exchange module includes multiple heat exchange tubes arranged side by side and heat exchange fins connected to both sides of the heat exchange tubes; the multiple heat exchange tubes are connected in parallel to the circulation pipeline, or the multiple heat exchange tubes are connected in series in a serpentine manner to the circulation pipeline.

[0012] Optionally, the heat exchange assembly includes a flexible pipe, and both the heat exchange inlet and the heat exchange outlet of the heat exchange module are connected to the flexible pipe.

[0013] Optionally, the heat exchange assembly includes an elbow, and the heat exchange inlet and heat exchange outlet of the heat exchange module are both connected to the elbow. One end of the elbow is connected to the heat exchange module, and the other end extends away from the graphitization kiln and is connected to the flexible pipe.

[0014] Optionally, the heat exchange module can be moved to contact the top of the graphitization kiln.

[0015] Optionally, the heat exchange module further includes at least one movable connection structure disposed on the heat exchange fins. The movable connection structure includes a lifting lug. The graphitization kiln enhanced cooling device further includes a gantry crane connected to the lifting lug for driving the heat exchange module to move.

[0016] Optionally, the heat exchange module further includes multiple temperature sensors connected to the heat exchange fins and protruding from the heat exchange module towards the side closer to the graphitization kiln. Each temperature sensor has multiple temperature measuring points at different distances from the heat exchange module.

[0017] Optionally, the circulation pipeline includes a riser, a downcomer, and two reducing pipes. Each reducing pipe has a larger diameter end and a smaller diameter end. The inlet and outlet of the riser are respectively connected to the smaller diameter ends of the two reducing pipes. The reducing pipe connected to the inlet of the riser has its larger diameter end leading to the heat exchange outlet of the heat exchange module. The reducing pipe connected to the outlet of the riser has its larger diameter end leading to the medium inlet of the coiled heat exchanger. The downcomer connects the heat exchange inlet of the heat exchange channel and the medium outlet of the coiled heat exchanger.

[0018] Optionally, the reducing tube is conical, and the inclination angle of the reducing tube wall is θ, satisfying 20°≤θ≤30°.

[0019] Optionally, the coil-type heat exchanger includes a heat exchange coil and a cooling chamber. The heat exchange coil is located inside the cooling chamber. The heat exchange coil has a medium inlet and a medium outlet. The cooling chamber is used to cool the heat transfer oil.

[0020] Optionally, the radius of the heat exchange coil is R1, and the radius of the cooling chamber is R, and R1≥2R / 3 is satisfied.

[0021] Optionally, the bending angle of the heat exchange coil is no greater than 15°.

[0022] Optionally, the medium inlet is located at the top of the heat exchange coil, the medium outlet is located at the bottom of the heat exchange coil, and the cooling chamber is provided with a cooling medium inlet and a cooling medium outlet, the cooling medium inlet being located at the bottom of the cooling chamber and the cooling medium outlet being located at the top of the cooling chamber.

[0023] Optionally, the supply assembly includes an oil boiling and storage tank, a first power pump, and a second power pump, wherein the oil boiling and storage tank is used for the storage and processing of the heat transfer oil;

[0024] The oil-boiling and storage tank is equipped with a return pipe and a supply pipe. The return pipe is connected to the circulation pipeline between the medium outlet and the heat exchange inlet. The supply pipe is connected to the circulation pipeline between the heat exchange outlet and the medium inlet. The supply pipe is also equipped with a one-way valve located between the oil-boiling and storage tank and the circulation pipeline. The first power pump is connected between the return pipe and the circulation pipeline. The first power pump is used to transport the heat transfer oil that has been cooled in the coil heat exchanger back to the oil-boiling and storage tank. The second power pump is connected to the circulation pipeline between the heat exchange outlet and the medium inlet, and is located between the supply pipe and the medium inlet. The second power pump is used to transport the processed heat transfer oil to the circulation pipeline to enter circulation.

[0025] Alternatively, the oil-boiling and storage tank is equipped with the supply pipe, which is connected to the circulation pipeline between the medium outlet and the heat exchange inlet. The first power pump is connected to the circulation pipeline between the medium outlet and the heat exchange inlet and is located between the supply pipe and the heat exchange inlet. The first power pump is used to transport the heat transfer oil in the oil-boiling and storage tank to the circulation pipeline for circulation. The second power pump is connected to the circulation pipeline between the heat exchange outlet and the medium inlet. The second power pump is used to transport the heat transfer oil that has completed heat exchange in the heat exchange module to the coil heat exchanger.

[0026] Optionally, the oil heating and storage tank includes an oil heater, an oil storage tank, and an expansion tank structure. The oil storage tank is used to store the heat transfer oil. The oil heater is located inside the oil storage tank and is used to heat the heat transfer oil. The expansion tank is used to release the pressure of the heat transfer oil when it is at a high temperature after heat treatment and during thermal expansion.

[0027] Optionally, the expansion tank is located at the highest point of the oil boiling and storage tank.

[0028] On the other hand, this utility model provides a waste heat recovery system, including the graphitization kiln enhanced cooling device, which realizes waste heat recovery by utilizing the heat absorbed by the coil heat exchanger of the cooling component.

[0029] The beneficial effects of this utility model are:

[0030] This invention provides an enhanced cooling device for a graphitization kiln, comprising a circulation pipeline for heat transfer oil flow, a heat exchange assembly, a cooling assembly, and a supply assembly. The supply assembly of this enhanced cooling device supplies treated heat transfer oil to the coil-type heat exchanger of the cooling assembly. After the cooling assembly cools the heat transfer oil, it is then transported to the heat exchange module for heat exchange with the graphitization kiln, accelerating the cooling rate of the kiln and significantly shortening the cooling cycle. Furthermore, by installing a movable heat exchange module on the graphitization kiln, the heat exchange module and the graphitization kiln can be connected... The independent setup not only avoids interference from the heat exchange module in subsequent processes of the graphitization kiln, reducing implementation difficulty, but more importantly, it allows for material suction operations on areas that have already been cooled by moving the heat exchange module, achieving simultaneous cooling and material suction, greatly shortening the production cycle and improving production efficiency. In addition, the heat transfer oil that has completed heat exchange with the graphitization kiln flows back to the coil heat exchanger for cooling. Furthermore, the heat absorbed by the coil heat exchanger can be recovered to power other equipment, thereby reducing resource waste and improving energy utilization.

[0031] This utility model also provides a waste heat recovery system. This waste heat recovery system recovers the heat during the cooling process of the heat transfer oil by utilizing the cooling module of the storage cooling component. The recovered heat can be used to power other equipment, thereby reducing resource waste and improving energy utilization. Attached Figure Description

[0032] Figure 1 This is a structural assembly drawing of the graphitization kiln enhanced cooling device provided by this utility model;

[0033] Figure 2 This is a schematic diagram of the circuit under the first working mode of the graphitization kiln enhanced cooling device provided by this utility model.

[0034] Figure 3 This is a schematic diagram of the circuit under the second working mode of the graphitization kiln enhanced cooling device provided by this utility model;

[0035] Figure 4 This is a schematic diagram of the heat exchange module in the enhanced cooling device for graphitization kilns provided by this utility model.

[0036] Figure 5 This is a schematic diagram of the structure of the temperature sensor in the graphitization kiln enhanced cooling device provided by this utility model when measuring the temperature of the insulation layer.

[0037] Figure 6 This is a plan view of the variable diameter pipe in the graphitization kiln enhanced cooling device provided by this utility model.

[0038] In the picture:

[0039] 100. Insulation layer;

[0040] 1. Heat exchange assembly; 11. Heat exchange module; 111. Heat exchange tube; 112. Heat exchange fins; 113. Lifting lug; 12. Flexible pipe; 13. Elbow; 14. Temperature sensor;

[0041] 2. Coil-type heat exchanger; 21. Heat exchange coil; 22. Cooling chamber; 221. Cooling medium inlet; 222. Cooling medium outlet;

[0042] 3. Supply components; 31. Oil storage tank; 32. First power pump; 33. Second power pump; 34. Check valve; 35. Return pipeline; 36. Supply pipeline;

[0043] 4. Ascending pipe;

[0044] 5. Downcomer;

[0045] 6. Reducing pipe. Detailed Implementation

[0046] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0047] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0048] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0049] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0050] In the operation of the graphitization kiln, electrodes are used as a heat source to efficiently heat the kiln, enabling its internal temperature to reach a peak of 3000℃. After the heating stage is completed, the cooling stage begins. Once the surface temperature has cooled to 500℃, a suction device is used to discharge the cooled insulation material or product, and this process is repeated until the discharge is complete.

[0051] Currently, two main cooling methods are used: natural cooling and fixed heat exchange equipment connected to the outside of the graphitization kiln. However, when using natural cooling, according to the current process, it takes about 8 hours to cool a material with a surface thickness of 15cm to below 500℃, which lengthens the single kiln discharge cycle to more than 20 days, severely restricting production efficiency and product output rate. On the other hand, when using fixed heat exchange equipment connected to the outside of the graphitization kiln, the kiln moves during the discharge process, making it difficult to implement. In addition, whether using natural cooling or heat exchange equipment, energy waste is very serious, and a large amount of heat energy released during the cooling process cannot be effectively recovered and utilized, resulting in poor energy utilization.

[0052] Therefore, in order to achieve at least one of the beneficial effects of shortening the cooling cycle, improving production efficiency, reducing resource waste, and improving the ease of implementation, this embodiment provides an enhanced cooling device for graphitization kilns.

[0053] like Figures 1 to 6 As shown, the graphitization kiln enhanced cooling device includes a circulation pipeline for the flow of heat transfer oil, a heat exchange component 1, a cooling component, and a supply component 3 connected to the circulation pipeline. The heat exchange component 1 includes a movable heat exchange module 11, which can be close to or away from the graphitization kiln. The heat exchange module 11 is provided with a heat exchange channel, which is connected to the circulation pipeline and has a heat exchange inlet and a heat exchange outlet. The cooling component includes a coil heat exchanger 2, which has a medium inlet for the inflow of heat transfer oil and a medium outlet for the outflow of heat transfer oil. The coil heat exchanger 2 is used to cool the heat transfer oil. The supply component 3 is used to store the heat transfer oil and supply heat transfer oil to the circulation pipeline.

[0054] The supply component 3 of the graphitization kiln enhanced cooling device supplies treated heat transfer oil to the coil-type heat exchanger 2 of the cooling component. After the heat transfer oil is cooled by the cooling component, it is transported to the heat exchange module 11 to exchange heat with the graphitization kiln, accelerating the cooling rate of the graphitization kiln and significantly shortening the cooling cycle. Furthermore, by setting a movable heat exchange module 11 on the graphitization kiln, the heat exchange module 11 is set independently from the graphitization kiln, which not only avoids the heat exchange module 11 affecting the subsequent processing of the graphitization kiln. The intervention in the sequence reduces the difficulty of implementation. More importantly, it allows for material suction operations on the area that has already been cooled by moving the heat exchange module 11, achieving simultaneous cooling and material suction, which greatly shortens the production cycle and improves production efficiency. In addition, the heat transfer oil that has completed heat exchange with the graphitization kiln flows back to the coil heat exchanger 2 for cooling. Furthermore, the heat absorbed by the coil heat exchanger 2 can be recovered to power other equipment, thereby reducing resource waste and improving energy utilization.

[0055] In this embodiment, the enhanced cooling device for the graphitization kiln mainly targets the cooling and temperature reduction of the insulation layer 100 at the top of the kiln. The heat transfer oil used for heat exchange with the insulation layer 100 is a specialized oil with good thermal stability, used for indirect heat transfer. It features uniform heating, accurate temperature control, the ability to generate high temperatures under low vapor pressure, good heat transfer efficiency, energy saving, and convenient transportation and operation. Examples include biphenyl-diphenyl ether mixtures, hydrogenated terphenyl, silicon-based heat transfer oil, and synthetic alkylbenzene heat transfer oil. In this embodiment, a specific heat capacity of 1.5-2.5 kJ / kg·K and a density of 700-1000 kg / m³ are used. 3 The heat transfer oil has a kinematic viscosity of 1-5 cSt (at 100°C), a flash point of 150-230°C, and an operating temperature range of 100-400°C. It is understood that in other embodiments, in addition to the heat transfer oil, other media with both good heat resistance and thermal conductivity can be selected to cool the insulation layer 100.

[0056] Optionally, the heat exchange module 11 includes multiple heat exchange tubes 111 arranged side by side and heat exchange fins 112 connected to both sides of the heat exchange tubes 111. The multiple heat exchange tubes 111 are connected in parallel to the circulation pipeline. By connecting heat exchange fins 112 to both sides of each heat exchange tube 111, the heat exchange area of ​​the heat exchange module 11 is increased, the heat exchange efficiency is improved, the cooling rate of the graphitization kiln is accelerated, the cooling cycle is shortened, and the multiple heat exchange tubes 111 are connected in parallel, so that each heat exchange tube 111 can perform heat exchange independently, improving the uniformity of heat exchange. In addition, the independent heat exchange of each heat exchange tube 111 means that even if a blockage occurs inside one heat exchange tube 111, the other heat exchange tubes 111 can still perform cooling operations normally.

[0057] Optionally, the heat exchange module 11 includes multiple heat exchange tubes 111 arranged side by side and heat exchange fins 112 connected to both sides of the heat exchange tubes 111. The multiple heat exchange tubes 111 are connected in series in a serpentine manner in the circulation pipeline. By connecting the multiple heat exchange tubes 111 in series in a serpentine manner in the circulation pipeline, the flow path of the heat transfer oil in the heat exchange module 11 is extended, and the flow time is extended, so that the heat transfer oil in the heat exchange module 11 can fully exchange heat with the graphitization kiln.

[0058] In this embodiment, the heat exchange tubes 111 and heat exchange fins 112 are connected by welding. This ensures that the heat exchange fins 112 fix the heat exchange tubes 111 and prevents the heat exchange tubes 111 from bending under thermal stress. To ensure a balanced flow of heat transfer oil in each heat exchange tube 111, a flow meter is installed at the heat exchange outlet of each heat exchange tube 111 to monitor the flow rate of the heat transfer oil. The number of heat exchange tubes 111 can be freely set according to the required heat exchange area.

[0059] Optionally, the heat exchange assembly 1 includes a flexible pipe 12, and both the heat exchange inlet and outlet of the heat exchange module 11 are connected to the flexible pipe 12. By connecting the flexible pipe 12 to both the heat exchange inlet and outlet of the heat exchange module 11, the flexible pipe 12 can adapt to deformation during movement of the heat exchange module 11, preventing damage to the connection points compared to a rigid connection. In this embodiment, the flexible pipe 12 is a corrugated hose, which not only has a certain degree of flexibility but also high heat resistance, with a maximum operating temperature of 650℃-950℃, thereby further reducing the impact of high temperatures on the flexible pipe 12. Optionally, the corrugated hose can be a corrugated hose made of metal, non-metal, or composite materials as described in the prior art; this invention is not limited to any particular type.

[0060] Optionally, the heat exchange assembly 1 includes an elbow 13. Both the heat exchange inlet and outlet of the heat exchange module 11 are connected to the elbow 13. One end of the elbow 13 is connected to the heat exchange module 11, and the other end extends away from the graphitization kiln and is connected to a flexible pipe 12. By connecting the flexible pipe 12 to the other end of the elbow 13 extending away from the graphitization kiln, the distance between the flexible pipe 12 and the graphitization kiln is increased, reducing the thermal impact of the high temperature of the graphitization kiln on the flexible pipe 12. In this embodiment, the elbow 13 is a 90° elbow.

[0061] Optionally, the heat exchange module 11 can be moved to contact the top of the graphitization kiln. Since the insulation layer 100 of the graphitization kiln is mainly located at the top of the kiln, moving the heat exchange module 11 to contact the top of the kiln is beneficial for cooling the insulation layer 100 located at the top of the kiln.

[0062] Optionally, the heat exchange module 11 further includes at least one movable connection structure, which is disposed on the heat exchange fins 112 and includes a lifting lug 113. The graphitization kiln enhanced cooling device also includes a gantry crane. In this embodiment, the gantry crane is connected to the lifting lug 113 and is used to drive the heat exchange module 11 to move. By providing the lifting lug 113 on the heat exchange fins 112, it is convenient to connect the gantry crane used to drive the heat exchange module 11 to the heat exchange module 11.

[0063] In this embodiment, the overhead crane includes a traveling device that moves along a track on the top of the workshop, and an electric hoist connected below the traveling device for lifting. The hook on the electric hoist is connected to the lifting lug 113. When it is necessary to move the heat exchange module 11, the traveling device is first started to move it directly above the heat exchange module 11. Then the electric hoist is started to control the hook to descend. The hook is then connected to the lifting lug 113. The electric hoist is started again to lift the heat exchange module 11. The traveling device is then started to move the heat exchange module 11. Once it reaches the desired position, the electric hoist is used to lower the heat exchange module 11 and separate the hook from the lifting lug 113, thus achieving the position adjustment of the heat exchange module 11.

[0064] In other embodiments, in addition to providing lifting lugs 113 on the heat exchange fins 112, threaded holes can also be opened on the heat exchange fins 112, and lifting rings can be threaded into the threaded holes, so that the lifting rings can be connected to the heat exchange fins 112 when lifting is required, and the lifting rings can be disassembled when lifting is not required. When connecting the lifting rings and the electric hoist, the two can be connected by slings.

[0065] Optionally, multiple temperature sensors 14 are connected to the heat exchange fins 112 and protrude from the heat exchange module 11 towards the side closer to the graphitization kiln. Each temperature sensor 14 has multiple temperature measuring points at different distances from the heat exchange module 11, such as reference points. Figure 4 As shown, the distances of the three temperature measuring points from the heat exchange module 11 (specifically, the heat exchange fins 112) are 50mm, 100mm, and 150mm, respectively. In other embodiments, the number and position of the temperature measuring points can be adjusted as needed. By setting the temperature sensor 14, the temperature of the insulation layer 100 on the top of the graphitization kiln is detected. When the temperature cools to the specified temperature, the position of the heat exchange module 11 is adjusted using a gantry crane to continue the cooling operation until the insulation layer 100 on the top of the graphitization kiln has cooled to the specified temperature. In addition, by setting multiple temperature measuring points at different distances, the accuracy of the temperature measurement is ensured.

[0066] In this embodiment, the temperature sensor 14 used to detect the temperature of the insulation layer 100 is a thermocouple. The side of the thermocouple inserted into the insulation layer 100 is tapered to facilitate insertion. In order to facilitate the connection between the temperature sensor 14 and the heat exchange fin 112, the heat exchange fin 112 is provided with a threaded through hole. The temperature sensor 14 is provided with an external thread that is threaded to the threaded through hole. By inserting the temperature sensor 14 into the threaded through hole of the heat exchange fin 112, the connection and fixation between the temperature sensor 14 and the heat exchange fin 112 can be achieved by screwing the temperature sensor 14.

[0067] Optionally, the circulation pipeline includes a riser pipe 4, a downcomer pipe 5, and two reducer pipes 6. Each reducer pipe 6 has a larger diameter end and a smaller diameter end. The inlet and outlet of the riser pipe 4 are respectively connected to the smaller diameter ends of the two reducer pipes 6. The reducer pipe 6 connected to the inlet of the riser pipe 4 has its larger diameter end leading to the heat exchange outlet of the heat exchange module 11. The reducer pipe 6 connected to the outlet of the riser pipe 4 has its larger diameter end leading to the medium inlet of the coil heat exchanger 2. The downcomer pipe 5 is connected between the heat exchange inlet of the heat exchange channel and the medium outlet of the coil heat exchanger 2.

[0068] By setting up riser pipe 4 and downcomer pipe 5, a channel for the heat transfer oil to circulate between heat exchange module 11 and coil heat exchanger 2 is formed in cooperation with flexible pipe 12. Furthermore, by connecting reducer pipe 6 to both the inlet and outlet of riser pipe 4, the flow rate of heat transfer oil can be accelerated when it enters riser pipe 4 through reducer pipe 6, and reduced when it flows out of riser pipe 4 through reducer pipe 6. This prolongs the heat exchange time of heat transfer oil in coil heat exchanger 2, thereby improving the cooling effect of coil heat exchanger 2 on heat transfer oil.

[0069] In this embodiment, the outer side of the circulation pipe is covered with thermal insulation cotton to provide thermal insulation and prevent leakage.

[0070] Optionally, such as Figure 6 As shown, the reducing pipe 6 is conical in shape, and the inclination angle of the wall of the reducing pipe 6 is θ, satisfying 20°≤θ≤30°. By limiting the inclination angle θ of the wall of the reducing pipe 6 to satisfy 20°≤θ≤30°, it is possible to avoid the inclination angle θ being too small, which would prevent it from accelerating the flow rate, and to avoid the inclination angle θ being too large, which would easily cause blockage. The inclination angle θ of the wall of the reducing pipe 6 is the angle between the wall of the reducing pipe 6 and the central axis of the reducing pipe 6.

[0071] The inclination angle θ of the wall of the reducing pipe 6 can be any value between 20° and 30° or any range between two values, such as 20°, 21°, 22°, 23°, 24°, 25°, 26°, 27°, 28°, 29°, 30°, etc.

[0072] Optionally, the coil-type heat exchanger 2 includes a heat exchange coil 21 and a cooling chamber 22. The heat exchange coil 21 is disposed inside the cooling chamber 22, and heat transfer oil flows within the heat exchange coil 21. The heat exchange coil 21 has a medium inlet and a medium outlet. The cooling chamber 22 is used to cool the heat transfer oil. By placing the heat exchange coil 21 within the cooling chamber 22 filled with cooling medium, the heat exchange coil 21, with the flowing heat transfer oil, is surrounded by the cooling chamber 22 containing the cooling medium, resulting in sufficient heat exchange area and high heat exchange efficiency. In this embodiment, condensate, serving as the cooling medium, flows within the cooling chamber 22.

[0073] In addition to the cooling chamber 22 provided in this embodiment for cooling the heat transfer oil, in other embodiments, heat exchange can also be achieved by winding a cooling pipe with condensate flowing inside the heat exchange coil 21 around the outside of the heat exchange coil 21. In this case, the cooling pipe replaces the cooling chamber 22. In addition, in other embodiments, liquid nitrogen can be supplied into the cooling chamber 22 to cool the heat transfer oil by vaporization of the liquid nitrogen, and then the vaporized gas of the liquid nitrogen is discharged through a gas-liquid separator.

[0074] Optionally, the radius of the heat exchange coil 21 is R1, and the radius of the cooling chamber 22 is R, satisfying R1≥2R / 3. Since the temperature of the heat transfer oil decreases after heat exchange with the condensate (which serves as the cooling medium), increasing its viscosity, the radius of curvature of the heat exchange coil 21 is limited to be no less than two-thirds of the radius of the cooling chamber 22. This ensures that the radius of curvature of the heat exchange coil 21 is sufficiently large, reducing the resistance to the flow of the heat transfer oil and allowing it to flow smoothly within the heat exchange coil 21 even after cooling.

[0075] Optionally, the bending angle of the heat exchange coil 21 is no greater than 15°. Since the temperature of the heat transfer oil decreases after heat exchange with the condensate, which serves as the cooling medium, the viscosity of the heat transfer oil increases. Therefore, by limiting the bending angle of the heat exchange coil 21 to no more than 15°, the resistance of the heat exchange coil 21 to the heat transfer oil at the corner is reduced, allowing the heat transfer oil to pass smoothly through the corner of the heat exchange coil 21 even after cooling.

[0076] Optionally, the medium inlet is located at the top of the heat exchange coil 21, and the medium outlet is located at the bottom of the heat exchange coil 21. The cooling chamber 22 is provided with a cooling medium inlet 221 and a cooling medium outlet 222. The cooling medium inlet 221 is located at the bottom of the cooling chamber 22, and the cooling medium outlet 222 is located at the top of the cooling chamber 22. By placing the medium inlet of the heat exchange coil 21 at the top and the medium outlet of the heat exchange coil 21 at the bottom, the flow direction of the heat transfer oil is from top to bottom. However, by placing the cooling medium inlet 221 at the bottom of the cooling chamber 22 and the cooling medium outlet 222 at the top of the cooling chamber 22, the flow direction of the cooling medium is from bottom to top. The flow direction of the cooling medium is exactly opposite to the flow direction of the heat transfer oil, thereby improving the heat exchange effect.

[0077] Optionally, the supply component 3 includes an oil boiling and storage tank 31, a first power pump 32, and a second power pump 33. The oil boiling and storage tank 31 is used for the storage and processing of heat transfer oil.

[0078] By adjusting the connection between the oil storage tank 31, the first power pump 32, the second power pump 33, and the circulation pipeline, two different supply modes can be formed.

[0079] like Figure 2 As shown, the first working mode is as follows: the oil storage tank 31 is equipped with a return pipe 35 and a supply pipe 36. The return pipe 35 is connected to the circulation pipe between the medium outlet and the heat exchange inlet. The supply pipe 36 is connected to the circulation pipe between the heat exchange outlet and the medium inlet. The first power pump 32 is connected between the return pipe 35 and the circulation pipe. The supply pipe 36 is also equipped with a one-way valve 34 located between the oil storage tank 31 and the circulation pipe. The first power pump 32 is used to transport the heat transfer oil that has been cooled by the coil heat exchanger 2 back to the oil storage tank 31. The second power pump 33 is connected to the circulation pipe between the heat exchange outlet and the medium inlet and is located between the supply pipe 36 and the medium inlet. The second power pump 33 is used to transport the processed heat transfer oil to the circulation pipe for circulation.

[0080] In this mode, the operation is as follows: First, the second power pump 33 inputs the heat transfer oil from the oil-boiling and storage tank 31 into the circulation pipeline between the heat exchange outlet and the medium inlet, providing power for the heat transfer oil to flow to the coil heat exchanger 2. When the heat transfer oil enters the coil heat exchanger 2 for cooling, the cooled heat transfer oil flows out from the medium outlet. At the junction of the return pipe 35 and the circulation pipeline, it is divided into two parts. One part of the heat transfer oil is drawn back into the oil-boiling and storage tank 31 by the first power pump 32 through the return pipe 35 for oil-boiling treatment to remove moisture and gas impurities from the heat transfer oil, ensuring that the properties of the heat transfer oil do not fluctuate drastically under high-temperature operation. The treated heat transfer oil then undergoes further processing... The second power pump 33 is input into the circulation pipeline between the heat exchange outlet and the medium inlet to participate in the circulation, while another part of the heat transfer oil continues to flow along the circulation pipeline towards the heat exchange module 11 and flows into the heat exchange module 11 to cool the graphitization kiln. Afterwards, it flows out from the heat exchange outlet of the heat exchange module 11 and merges with the heat transfer oil that has completed the oil boiling treatment, and continues to flow towards the coil heat exchanger 2. In this mode, the content of moisture and gas impurities in the heat transfer oil can be controlled while cooling the graphitization kiln, avoiding excessive moisture and gas impurity content, which would cause the properties of the heat transfer oil to be unstable under high temperature operation, resulting in violent fluctuations and affecting the stability of the system.

[0081] like Figure 3 As shown, the second working mode is as follows: the oil storage tank 31 is equipped with a supply pipe 36, which is connected to the circulation pipe between the medium outlet and the heat exchange inlet. The first power pump 32 is connected to the circulation pipe between the medium outlet and the heat exchange inlet and is located between the supply pipe 36 and the heat exchange inlet. The first power pump 32 is used to transport the heat transfer oil in the oil storage tank 31 to the circulation pipe for circulation. The second power pump 33 is connected to the circulation pipe between the heat exchange outlet and the medium inlet. The second power pump 33 is used to transport the heat transfer oil that has completed heat exchange in the heat exchange module 11 to the coil heat exchanger 2.

[0082] The operation in this mode is as follows: First, the heat transfer oil is boiled in the oil storage tank 31 to remove moisture and gas impurities. Then, the heat transfer oil is pumped from the oil storage tank 31 through the supply pipe 36 to the circulation pipeline between the medium outlet and the heat exchange inlet via the first power pump 32. It then enters the heat exchange module 11 through the heat exchange inlet to cool the graphitization kiln. Next, the second power pump 33 pumps the heat transfer oil flowing from the heat exchange outlet of the heat exchange module 11 to the coil heat exchanger 2 for cooling. After cooling, the heat transfer oil continues to flow back to the heat exchange module 11 to cool the graphitization kiln. Since the heat transfer oil experiences losses during circulation, the first power pump 32... 2. By continuing to transport the heat transfer oil in the oil storage tank 31 to the circulation pipeline between the medium outlet and the heat exchange inlet, the lost heat transfer oil is replenished. In this mode, since both the first power pump 32 and the second power pump 33 are located on the circulation pipeline, the first power pump 32 and the second power pump 33 can serve as a double insurance. Compared with a system with only one oil pump, even if one of them fails, it will not affect the circulation of the cooling medium. In high-temperature operating environments, although the viscosity of the heat transfer oil is low, corrosion of the oil pump may still occur during long-term operation. By using a one-in-one-out configuration, the oil pump can be changed without stopping the system to ensure continuous operation of the device.

[0083] Optionally, the oil heating and storage tank 31 includes an oil heater, an oil storage tank, and an expansion tank. The oil storage tank stores the heat transfer oil, the oil heater is located inside the oil storage tank, and the oil heater is used to heat and treat the heat transfer oil. The expansion tank is used to handle the pressure release during thermal expansion of the heat transfer oil at high temperatures after heat treatment. By installing an oil heater in the oil storage tank, the heat transfer oil is heated before circulation begins, removing moisture and gaseous impurities. This ensures that the properties of the heat transfer oil do not fluctuate drastically under high-temperature operation, guaranteeing normal equipment operation and extending equipment service life.

[0084] In this embodiment, the oil storage tank 31 is actually a thermal oil heater in the prior art, a special type of direct-flow boiler used for heating crude oil and natural gas. Thermal oil heaters are also called organic heat carrier boilers, commonly known as thermal oil boilers, and officially called hot oil heaters. They are a new type of thermal energy equipment that uses coal, oil, or gas as fuel and thermal oil as the circulating medium for heating. The advantages of thermal oil heaters lie in their "high temperature and low pressure" and stable operation, leading to their widespread use.

[0085] Among them, the types of oil cookers mainly include raw coal type, fuel oil type, electric heating type and coal-water slurry type. The type of oil cooker can be freely selected according to the needs. In this embodiment, the type of oil cooker is electric heating type, which uses an electric heating rod to extend into the oil storage tank for heating, or it can use an electric heating wire to heat the inside of the oil storage tank.

[0086] Optionally, the expansion tank is located at the highest point of the oil boiling and storage tank 31. By placing the expansion tank at the highest point of the oil boiling and storage tank 31, the gas, being lighter than air, naturally rises and accumulates in the expansion tank. The gas in the system is then removed through periodic venting operations, ensuring the purity and heat transfer performance of the heat transfer oil.

[0087] In this embodiment, the main functions of the expansion tank include accommodating the volume of the heat transfer fluid as it expands due to heat, venting light components from newly filled products and low-boiling substances generated during operation, compensating for evaporation and operational losses, and providing nitrogen sealing. The expansion tank is configured as a conventional structure for thermal oil furnaces, and this utility model does not impose any special limitations on it.

[0088] Taking the first working mode as an example, when cooling the graphitization kiln using the enhanced cooling device, the heat exchange module 11 is first placed on top of the graphitization kiln using a gantry crane. Then, the heat transfer oil is boiled in the oil storage tank 31 to remove moisture, low volatile matter, and other gaseous impurities. Afterwards, it is pumped to the riser pipe 4 for circulation using the second power pump 33. The heat transfer oil flowing out of the riser pipe 4 passes through the reducer pipe 6 and enters the heat exchange coil 21. The cooling medium in the cooling chamber 22 cools the heat transfer oil. After cooling, the heat transfer oil flows out of the heat exchange coil 21 and then sequentially passes through the downcomer pipe 5, flexible pipe 12, and elbow 13. A portion of the heat transfer oil is then pumped back to the oil storage tank 31 by the first power pump 32 for further boiling treatment. After being processed, the heat transfer oil is pumped back into the riser pipe 4 by the second power pump 33 to participate in circulation. Another part of the heat transfer oil enters the heat exchange module 11. In the heat exchange module 11, the heat transfer oil is cooled by the insulation layer 100 on the top of the graphitization kiln. After completing the heat exchange, the heat transfer oil flows out of the heat exchange module 11 and passes through the bend 13 and the flexible pipe 12 into the reducer pipe 6. After the reducer pipe 6 accelerates the flow, it enters the riser pipe 4 and circulates to cool the graphitization kiln until the insulation layer 100 of the graphitization kiln is cooled to the required temperature. At the same time, the cooling medium after cooling the heat transfer oil is heated and vaporized to form high-temperature steam. The high-temperature steam is then input into the equipment that uses high-temperature steam as an energy source for energy supply. This achieves both accelerated cooling of the graphitization kiln and improved resource utilization through heat recovery. When the heat exchange module 11 is used to cool the top of the graphitization kiln, the temperature of the graphitization kiln is monitored at any time by the temperature sensor 14. When the area reaches the cooling temperature, the material can be sucked into the area. At the same time, the position of the heat exchange module 11 is moved by the overhead crane to continue cooling another area. This achieves simultaneous cooling and material suction, which greatly shortens the operation cycle and improves production efficiency.

[0089] In this embodiment, a waste heat recovery system is also provided, which recovers waste heat by utilizing the heat absorbed by the coil-type heat exchanger 2 of the cooling assembly.

[0090] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A cooling device for graphitization kilns, characterized in that, It includes a circulation pipeline for the flow of heat transfer oil, a heat exchange assembly (1) and a cooling assembly disposed on the circulation pipeline, and a supply assembly (3) connected to the circulation pipeline, wherein: The heat exchange assembly (1) includes a movable heat exchange module (11), which can be close to and away from the graphitization kiln. The heat exchange module (11) is provided with a heat exchange channel, which is connected to the circulation pipeline. The heat exchange channel is provided with a heat exchange inlet and a heat exchange outlet. The cooling assembly includes a coil heat exchanger (2), which has a medium inlet for the heat transfer oil to flow into and a medium outlet for the heat transfer oil to flow out. The coil heat exchanger (2) is used to cool the heat transfer oil. The supply component (3) is used for storing the heat transfer oil and supplying the heat transfer oil to the circulation pipeline.

2. The enhanced cooling device for graphitization kilns according to claim 1, characterized in that, The heat exchange assembly (1) includes at least one of the following features: I. The heat exchange module (11) includes a plurality of heat exchange tubes (111) arranged side by side and heat exchange fins (112) connected to both sides of the heat exchange tubes (111); the plurality of heat exchange tubes (111) are connected in parallel to the circulation pipeline, or the plurality of heat exchange tubes (111) are connected in series in a serpentine manner to the circulation pipeline; II. The heat exchange assembly (1) includes a flexible pipe (12), and the heat exchange inlet and the heat exchange outlet of the heat exchange module (11) are both connected to the flexible pipe (12); III. The heat exchange component (1) includes an elbow (13). The heat exchange inlet and the heat exchange outlet of the heat exchange module (11) are both connected to the elbow (13). One end of the elbow (13) is connected to the heat exchange module (11), and the other end extends away from the graphitization kiln and is connected to the flexible pipe (12). IV. The heat exchange module (11) can be moved to contact the top of the graphitization furnace.

3. The enhanced cooling device for graphitization kilns according to claim 2, characterized in that, The heat exchange assembly (1) includes at least one of the following conditions: I. The heat exchange module (11) further includes at least one movable connection structure, which is disposed on the heat exchange fins (112). The movable connection structure includes a lifting lug (113). The graphitization kiln enhanced cooling device further includes a gantry crane, which is connected to the lifting lug (113) and is used to drive the heat exchange module (11) to move. II. The heat exchange module (11) further includes multiple temperature sensors (14), which are connected to the heat exchange fins (112) and protrude from the heat exchange module (11) towards the side closer to the graphitization kiln. Each temperature sensor (14) has multiple temperature measuring points at different distances from the heat exchange module (11).

4. The enhanced cooling device for graphitization kilns according to claim 2, characterized in that, The circulation pipeline includes an ascending pipe (4), a descending pipe (5), and two reducing pipes (6). Each reducing pipe (6) has a larger diameter end and a smaller diameter end. The inlet and outlet of the ascending pipe (4) are respectively connected to the smaller diameter ends of the two reducing pipes (6). The reducing pipe (6) connected to the inlet of the ascending pipe (4) has its larger diameter end leading to the heat exchange outlet of the heat exchange module (11). The reducing pipe (6) connected to the outlet of the ascending pipe (4) has its larger diameter end leading to the medium inlet of the coil heat exchanger (2). The descending pipe (5) is connected between the heat exchange inlet of the heat exchange channel and the medium outlet of the coil heat exchanger (2).

5. The enhanced cooling device for graphitization kilns according to claim 4, characterized in that, The reducing tube (6) is conical in shape, and the inclination angle of the wall of the reducing tube (6) is θ, which satisfies 20°≤θ≤30°.

6. The enhanced cooling device for graphitization kilns according to claim 1, characterized in that, The coil heat exchanger (2) includes a heat exchange coil (21) and a cooling chamber (22). The heat exchange coil (21) is located inside the cooling chamber (22). The heat exchange coil (21) has a medium inlet and a medium outlet. The cooling chamber (22) is used to cool the heat transfer oil.

7. The enhanced cooling device for graphitization kilns according to claim 6, characterized in that, The coil heat exchanger (2) includes at least one of the following conditions: I. The radius of the heat exchange coil (21) is R1, and the radius of the cooling chamber (22) is R, and R1≥2R / 3 is satisfied; II. The bending angle of the heat exchange coil (21) is not greater than 15°; III. The medium inlet is located at the top of the heat exchange coil (21), the medium outlet is located at the bottom of the heat exchange coil (21), and the cooling chamber (22) is provided with a cooling medium inlet (221) and a cooling medium outlet (222). The cooling medium inlet (221) is located at the bottom of the cooling chamber (22), and the cooling medium outlet (222) is located at the top of the cooling chamber (22).

8. The enhanced cooling device for graphitization kilns according to claim 1, characterized in that, The supply component (3) includes an oil boiling and storage tank (31), a first power pump (32) and a second power pump (33). The oil boiling and storage tank (31) is used for the storage and processing of the heat transfer oil. The oil storage tank (31) is provided with a return pipe (35) and a supply pipe (36). The return pipe (35) is connected to the circulation pipeline between the medium outlet and the heat exchange inlet. The supply pipe (36) is provided to the circulation pipeline between the heat exchange outlet and the medium inlet. The supply pipe (36) is also provided with a one-way valve (34) located between the oil storage tank (31) and the circulation pipeline. The first power pump (32) is connected between the return pipe (35) and the circulation pipeline. The first power pump (32) is used to transport the heat transfer oil that has been cooled in the coil heat exchanger (2) back to the oil storage tank (31). The second power pump (33) is connected to the circulation pipeline between the heat exchange outlet and the medium inlet, and is located between the supply pipe (36) and the medium inlet. The second power pump (33) is used to transport the heat transfer oil that has been processed to the circulation pipeline to enter circulation. Alternatively, the oil storage tank (31) is provided with the supply pipe (36), the supply pipe (36) is connected to the circulation pipeline between the medium outlet and the heat exchange inlet, the first power pump (32) is connected to the circulation pipeline between the medium outlet and the heat exchange inlet, and is located between the supply pipe (36) and the heat exchange inlet. The first power pump (32) is used to transport the heat transfer oil in the oil storage tank (31) to the circulation pipeline for circulation. The second power pump (33) is connected to the circulation pipeline between the heat exchange outlet and the medium inlet. The second power pump (33) is used to transport the heat transfer oil that has completed heat exchange in the heat exchange module (11) to the coil heat exchanger (2).

9. The enhanced cooling device for graphitization kilns according to claim 8, characterized in that, The oil boiling and storage tank (31) includes at least one of the following conditions: I. The oil heating and storage tank (31) includes an oil heater, an oil storage tank and an expansion tank structure. The oil storage tank is used to store the heat transfer oil. The oil heater is located inside the oil storage tank. The oil heater is used to heat the heat transfer oil. The expansion tank is used to release the pressure of the heat transfer oil when it is at a high temperature after heat treatment and during thermal expansion. II. The expansion tank is located at the highest position of the oil boiling and storage tank (31).

10. A waste heat recovery system, characterized in that, The graphitization kiln enhanced cooling device as described in any one of claims 1-9 achieves waste heat recovery by utilizing the heat absorbed by the coil heat exchanger (2) of the cooling assembly.

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