Heat balance system for NMP coating recovery device

Abstract

The utility model belongs to the technical field of recovery, and particularly relates to a heat balance system for an NMP (N-Methyl Pyrrolidone) coating recovery device, which comprises an NMP recovery module, a heat pump system module, a heat balance module and a coating oven module which are sequentially connected, and the coating oven module, the heat balance module and the heat pump system module are sequentially connected to form a heat medium water balance loop. The NMP recovery module, the heat pump system module, the heat balance module and the coating drying oven module are sequentially connected, so that comprehensive utilization of energy in the coating drying process, the NMP recovery process and the working process of the heat pump module is achieved, the energy-saving effect is improved, and control over heat balance can be achieved through the arrangement of the heating medium water balance loop; the system can better manage temperature and heat balance.

Description

Technical Field

[0001] The utility model relates to the technical field of recycling, in particular to a heat balance system for an NMP coating recycling device. Background Art

[0002] During the production and manufacturing process of lithium batteries, the coating machine will generate a large amount of high-temperature NMP waste gas, which needs to be recovered and treated using an NMP recovery system. The drying of the coating and the recovery of NMP consume a lot of energy.

[0003] In the traditional process, the temperature of NMP waste gas drops to about 15°C after condensation treatment before entering the next process. Some NMP waste gas needs to be heated to about 110°C before returning to the coater. However, the operating energy consumption of this process is often relatively high because the condensation and heating treatments of the waste gas are carried out separately, and the cold and heat cannot be used efficiently. When the cold and heat are used in a comprehensive manner, it is easy to have a cold and heat imbalance due to the inability to regulate the heat and cold separately, resulting in the inability to accurately control the temperature during electrode drying and NMP waste gas treatment.

[0004] Based on this, it is urgent to invent a heat balance system for NMP coating recovery device. Utility Model Content

[0005] The utility model aims to provide a heat balance system for an NMP coating recovery device in view of the deficiencies in the prior art, which not only has a good energy-saving effect, but also has a good heat balance effect for each part of the system, is easy to accurately control the temperature, and ensures an excellent production process for the battery.

[0006] To achieve the above objectives, this application adopts the following technical solutions:

[0007] Provided is a heat balance system for an NMP coating recovery device, comprising an NMP recovery module, a heat pump system module, a heat balance module and a coating oven module connected in sequence, wherein the coating oven module, the heat balance module and the heat pump system module are connected in sequence to form a heat medium water balance loop, the heat pump system module is used to convert low-grade heat flowing out of the NMP recovery module into high-grade heat, and the heat balance module is used to aggregate, store and temperature balance the high-grade heat converted by the heat pump system module.

[0008] Specifically, the coating oven module includes a coating oven, a circulating fan and a high-temperature heat exchanger, the heat balance module includes a hot water pump and a hot water tank, the heat pump system module includes a low-temperature refrigerant heat exchanger, a high-temperature refrigerant heat exchanger and a heat pump unit, and the heat medium water balance loop starts from the high-temperature refrigerant heat exchanger and passes through the hot water tank, the high-temperature heat exchanger and the hot water pump in sequence before returning to the high-temperature refrigerant heat exchanger.

[0009] Specifically, multiple sets of the heat pump units are provided, and the heat medium water flowing through the heat pump units all flows into the same hot water tank.

[0010] Specifically, the heat pump system module is connected to the NMP recovery module to form a chilled water circuit, and the coating oven module is connected to the NMP recovery module to form a gas circulation circuit.

[0011] Specifically, the NMP recovery module includes an air-air heat exchanger, a low-temperature heat exchanger, and an exhaust fan. The gas circulation circuit starts from the coating oven and sequentially passes through the exhaust fan, the air-air heat exchanger, the low-temperature heat exchanger, the air-air heat exchanger, the circulation fan, and the high-temperature heat exchanger, and finally returns to the coating oven; the chilled water circuit starts from the low-temperature chilled water heat exchanger and sequentially passes through the chiller, the chilled water pump, and the low-temperature heat exchanger and then flows back to the low-temperature chilled water heat exchanger.

[0012] Specifically, there are multiple heat pump units, and multiple heat pump units are all connected to the same low-temperature chilled water heat exchanger and the same high-temperature heat exchanger.

[0013] Specifically, the chilled water circuit is connected to a surface cooler, and the surface cooler exchanges heat with the pole pieces in the heat dissipation area through air.

[0014] Specifically, the gas circulation circuit is further connected with an auxiliary heater.

[0015] Specifically, the coating oven has multiple sections, and each section of the coating oven is connected to the gas circulation circuit and the heat medium water balance circuit.

[0016] Specifically, a tail gas treatment system is further included.

[0017] The beneficial effects of the present utility model are as follows: By sequentially connecting the NMP recovery module, the heat pump system module, the heat balance module, and the coating oven module, the comprehensive utilization of energy in the coating drying process, the NMP recovery process, and the working process of the heat pump module is realized, so as to improve the energy-saving effect. And through the setting of the heat medium water balance circuit, the control of heat balance can be realized, and the system can better manage the temperature and heat balance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present utility model and constitute a part of the present utility model. The schematic embodiments and descriptions thereof are used to explain the present utility model and do not constitute an improper limitation to the present utility model. In the drawings:

[0019] Figure 1 is a schematic structural diagram of Embodiment 1 in the present utility model;

[0020] Figure 2 It is a schematic structural diagram of Embodiment 3 in the present utility model;

[0021] Figure 3 It is a schematic structural diagram of the heat pump system module in Embodiment 4 of the present utility model.

[0022] Wherein: 1 - NMP recovery module; 11 - gas-gas heat exchanger; 12 - low-temperature heat exchanger; 13 - exhaust fan; 14 - tail gas treatment system; 2 - heat pump system module; 21 - low-temperature refrigerant heat exchanger; 22 - high-temperature refrigerant heat exchanger; 23 - heat pump unit; 24 - chiller; 3 - heat balance module; 31 - hot water pump; 32 - hot water tank; 33 - heat pump unit; 4 - coating oven module; 41 - coating oven; 42 - circulation fan; 43 - high-temperature heat exchanger; 44 - auxiliary heater; 5 - heat medium water balance circuit; 6 - chilled water circuit; 7 - gas circulation circuit. Specific embodiments

[0023] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs. The terms used in the specification of the present application herein are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0024] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "installation", "connection", "connection", and "fixation" shall 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, and 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 utility model can be understood according to specific circumstances.

[0025] Although the present application is disclosed above in a preferred embodiment, it is not used to limit the claims. Any person skilled in the art can make several possible changes and modifications without departing from the concept of the present application. Therefore, the protection scope of the present application should be subject to the scope defined by the claims of the present application.

[0026] Such as Figure 1As shown, the inventor found that in the existing technology, the coating drying process and the NMP recovery process are set as two separate processes. When providing heat for coating drying, the heat pump directly discharges the cold energy into nature. When providing cold energy for NMP recovery through the heat pump, the heat is directly discharged into nature, resulting in a double waste of heat and cold energy, and the discharged heat and cold energy will also have an impact on the environment. Therefore, in order to complement the energy of the NMP recovery module 1 and the coating oven module 4, the inventor connected the NMP recovery module 1, the heat pump system module 2, and the coating oven module 4 together to achieve efficient recycling of energy. Since the NMP recovery module 1, the heat pump system module 2, and the coating oven module 4 are all connected together, the heat pump cannot separately adjust the temperature of the NMP recovery module 1 or the coating oven module 4. Therefore, the inventor set up a refrigerant water circuit 6 to adjust the cold balance in the circulation circuit, improving the stability of the temperature and the heat and cold balance in the system.

[0027] Embodiment 1

[0028] As Figure 1 shown, a heat balance system for an NMP coating recovery device includes an NMP recovery module 1, a heat pump system module 2, a heat balance module 3, and a coating oven module 4 connected in sequence.

[0029] The NMP recovery module 1 is used to recover the NMP evaporated during the drying process of the electrode sheet, prevent NMP from polluting the environment, and reuse the NMP.

[0030] The coating oven module 4 is used to dry the coated electrode sheet.

[0031] The heat pump system module 2 is used to convert the low-grade heat flowing out of the NMP recovery module 1 into high-grade heat, and the generated cold energy and heat are respectively supplied to the NMP recovery module 1 and the coating oven module 4.

[0032] The heat balance module 3 is used to collect and store the heat provided by the heat pump system module 2 and control the temperature balance.

[0033] The coating oven module 4, the heat balance module 3, and the heat pump system module 2 are connected in sequence to form a heat medium water balance circuit 5.

[0034] By connecting the NMP recovery module 1, heat pump system module 2, heat balance module 3, and coating oven module 4 in sequence, a closed energy cycle is formed in the whole system, reducing waste, increasing efficiency, and being conducive to energy conservation, emission reduction, and environmental protection. This method is a progress in industrial applications such as battery production, aiming to improve the continuous production capacity and the economy of sustainable development. The heat medium water balance loop 5 controls the temperature balance of the heat medium water after entering the heat balance module 3, making the temperature of the heat medium water entering the coating oven module 4 for heat exchange stable, which is conducive to precisely adjusting the temperature of the oven, thereby improving the stability of the whole system.

[0035] Specifically, the coating oven module 4 includes a coating oven 41, a circulation fan 42, and a high-temperature heat exchanger 43. The coating oven 41 plays an important role in the coating process. Through precise temperature control, it ensures the coating quality and effect, enabling the coating to be evenly coated and cured. And the coating oven 41 can meet the synthesis and drying requirements of different types of coatings by designing adjustable temperature, humidity, and wind speed. The circulation fan 42 is used to form a gas flow system to maintain the air flow in the oven, ensuring the uniform drying of the coating and promoting the recycled air to return to the oven for the next cycle. The high-temperature heat exchanger 43 can transfer the heat of the chilled water to the circulating return air.

[0036] The heat balance module 3 includes a cold and hot water pump 31 and a hot water tank 32. The heat balance module 3 stores and mixes the heat medium water by passing it into the hot water tank 32, making the temperature in the hot water tank 32 consistent. And because a large amount of chilled water is stored, the heat medium water in the hot water tank 32 is not easily affected by the temperature change of the newly entered heat medium water, making the heat medium water in the heat medium water balance loop 5 have good temperature stability. In the high-temperature heat exchanger 43, the temperature of the circulating return air after passing through the high-temperature heat exchanger 43 is adjusted by regulating the flow rate of the heat medium water. The stable temperature of the heat medium water is conducive to precisely controlling the temperature of the circulating return air, enabling the stable drying of the electrode sheet. The stable temperature can make the coating layer uniformly cured during the drying process, avoiding uneven coating thickness and inconsistent circuit performance caused by temperature fluctuations, thereby improving the quality of battery products.

[0037] Specifically, the heat medium water balance loop 5 starts from the high-temperature refrigerant heat exchanger 22, passes through the hot water pump and the high-temperature heat exchanger 43 in sequence, and then returns to the high-temperature refrigerant heat exchanger 22.

[0038] More specifically, the heat medium water balance circuit 5 is: the high-temperature refrigerant heat exchanger 22 serves as the condenser of the heat pump unit 33, and produces high-temperature heat medium water of about 130°C by absorbing high-grade heat. The high-temperature heat medium water enters the hot water tank 32 and mixes with the heat medium water in the hot water tank 32. Under the action of the hot water pump 31, the heat medium water fully mixed in the hot water tank 32 enters the high-temperature heat exchanger 43, and the heat is transferred from the high-temperature heat medium water to the high-temperature heat exchanger 43, and then the heat is transferred to the circulating return air blown out by the circulating fan 42, so as to heat the circulating return air. After the heat is transferred to the high-temperature heat exchanger 43, the temperature of the high-temperature heat medium water drops, and then enters the heat pump unit 33 again for heat exchange.

[0039] There are multiple sets of heat pump units 33, and the heat medium water flowing through the heat pump units 33 all flows into the same hot water tank 32. Through this arrangement, the heat medium water of all heat pump units 33 can be changed to flow into the same hot water tank 32. Through the heat storage capacity of the tank, the temperature inside the system can be ensured to be relatively stable, reducing temperature fluctuations, which is conducive to maintaining a constant coating and drying heating environment.

[0040] The heat pump system module 2 is connected to the NMP recovery module 1 to form a refrigerant water loop 6, and the coating oven module 4 is connected to the NMP recovery module 1 to form a gas circulation loop 7.

[0041] Specifically, the NMP recovery module 1 includes an air-to-air heat exchanger 11, a low-temperature heat exchanger 12 and an exhaust fan 13. The gas circulation loop 7 starts from the coating oven 41, passes through the exhaust fan 13, the air-to-air heat exchanger 11, the low-temperature heat exchanger 12, the air-to-air heat exchanger 11, the circulation fan 42 and the high-temperature heat exchanger 43 in sequence, and finally returns to the coating oven 41; the refrigerant water loop 6 starts from the low-temperature refrigerant heat exchanger 21, passes through the chiller 24, the cold water pump and the low-temperature heat exchanger 12 in sequence, and then flows back to the low-temperature refrigerant heat exchanger 21.

[0042] More specifically, the refrigerant water circuit 6 is: the heat pump unit 33 recovers the low-grade heat of the low-temperature heat exchanger 12 of the NMP recovery module 1, and converts it into high-grade heat after passing through the low-temperature compressor and the high-temperature compressor. At the heat pump unit 33, the low-temperature refrigerant heat exchanger 21 serves as the evaporator of the heat pump unit 33, and the refrigerant water absorbs the low-grade heat to produce refrigerant water of about 7°C. After passing through the heat pump unit 33, the temperature of the refrigerant water cannot reach about 7°C. The refrigerant water continues to pass through the chiller 24 to further reduce the refrigeration temperature to about 7°C. After passing through the cold water pump, the refrigerant water is pressurized and passes through the low-temperature heat exchanger 12 to reduce the temperature of the low-temperature heat exchanger 12, which is used for cooling and condensing the exhaust gas of the NMP recovery module 1.

[0043] More specifically, the gas circulation loop 7 is as follows: The NMP waste gas at about 110°C discharged from the exhaust fan 13 of the coating oven module 4 is initially cooled to 30 - 40°C after heat exchange with the circulating return air in the gas-gas heat exchanger 11, and further cooled to 15 - 18°C after heat exchange with chilled water in the low-temperature heat exchanger 12. After the NMP condensed droplets are intercepted and collected by the demister, 5 - 10% of the exhaust gas is discharged to the atmosphere after environmental protection treatment through the exhaust gas treatment system 14, while 90 - 95% is used as circulating return air. After heat exchange in the gas-gas heat exchanger 11, it returns to the coating oven module 4 through the circulation fan 42. In the coating oven module 4, the circulating return air exits the gas-gas heat exchanger 11, passes through the circulation fan 42, and after being heated and raised in temperature by the high-temperature heat exchanger 43, returns to the coating oven 41. The dry high-temperature gas returning to the oven absorbs a large amount of NMP after purging the electrode sheet, and then returns to the NMP recovery module 1 under the action of the exhaust fan 13, and the electrode sheet becomes dry after passing through the coating oven 41.

[0044] In some embodiments, a water replenishing tank and a water replenishing pump are also provided. The chiller 24 is connected to the hot water tank 32 and the water replenishing pump. When the refrigerant water circuit 6 or the heat medium water balance circuit 5 is short of water, the water in the water replenishing tank can be replenished to the chiller 24 or the hot water tank 32 through the water replenishing pump.

[0045] Through the settings of the gas circulation loop 7, the refrigerant water circuit 6, and the heat medium water balance circuit 5, the present application can achieve the efficient utilization of the heat and cold of the heat pump, improve the efficiency of the entire system, reduce energy waste, and also conform to the environmental protection concept.

[0046] Embodiment 2

[0047] Different from Embodiment 1: The gas circulation loop 7 is also connected with an auxiliary heater 44. When the circulating return air passes through the high-temperature heat exchanger 43 and then through the auxiliary heater 44, the temperature of the circulating return air after passing through the high-temperature heat exchanger 43 can be adjusted again. The coating oven 41 has multiple sections, and each section of the coating oven 41 is connected to the gas circulation loop 7 and the heat medium water balance circuit 5, and the temperature of each oven can be independently controlled to precisely control the temperature of different areas to meet the coating treatment requirements at different stages, such as maintaining the best drying or curing conditions, improving production efficiency and product quality. Each oven can be adjusted through its respective control system to ensure the precise execution of the process.

[0048] The inlet and outlet of the high-temperature heat exchanger 43 are respectively connected to the outlet and inlet of the high-temperature refrigerant heat exchanger 22 of the heat pump system module 2 through high-temperature heat medium water pipes. Each oven can control the temperature of the circulating return air of the oven by setting a separate high-temperature refrigerant heat exchanger 22 and respectively controlling the flow rate of the heat medium water flowing through the high-temperature refrigerant heat exchanger 22. Since the return air temperature requirements of each coating oven 41 are different, only controlling the flow rate of the heat medium water cannot meet the temperature requirements of all ovens. At this time, the auxiliary heater 44 is connected to the auxiliary heating system (such as heat-conducting oil or steam) to assist in heating the return air, so as to achieve the purpose of heating and temperature control, and achieve a wider range of temperature adjustment. When affected by the ambient temperature, when the ambient temperature is relatively low, the heat required by the oven increases, while the cooling capacity required at the low-temperature heat exchanger 12 decreases, resulting in insufficient heat at the high-temperature refrigerant heat exchanger 22 and sufficient cooling capacity at the low-temperature refrigerant heat exchanger 21. The auxiliary heater 44 can be turned on to generate additional heat for supplementation to meet the temperature and heat requirements of the oven, and the heat balance of the coating recovery device can be adjusted. By setting the auxiliary heater 44 and the chiller 24, the heat balance of the refrigerant water circuit 6 and the gas circulation circuit 7 can be controlled, making the heat and cold balance of the coating recovery device better.

[0049] Preferably, temperature detectors are provided in the refrigerant water circuit 6, the heat medium water balance circuit 5, and the gas circulation circuit 7. The temperature detectors ensure an automated adjustment process and can maintain the heat balance between the circuits. This not only helps to save energy, but also improves the energy utilization efficiency of the coating recovery device, reduces operating costs, enables the coating recovery device to adapt to external temperature changes, and ensures the stable progress of the process.

[0050] Preferably, controllers are provided for both the circulation fan 42 and the exhaust fan 13, which can control the wind speed in real time and are connected to temperature sensors. The wind speed passing through the low-temperature heat exchanger 12 and the high-temperature heat exchanger 43 can be controlled according to the controlled temperature, thereby adjusting the heat transfer and regulating the energy balance of the entire coating recovery device.

[0051] Preferably, an exhaust gas treatment system 14 is also provided. Through the exhaust gas treatment system 14, the exhaust gas can be discharged. Since the exhaust gas continuously flows out, the negative pressure of the oven can be maintained to prevent NMP from flowing out and polluting the environment.

[0052] Others are the same as those in Embodiment 1 and will not be elaborated here.

[0053] Embodiment 3

[0054] As Figure 2As shown, different from Embodiment 1: There are multiple heat pump units 33, and the multiple heat pump units 33 are all connected to the same low-temperature refrigerant heat exchanger 21 and the same high-temperature refrigerant heat exchanger 22. The refrigerant of each heat pump unit 33 is introduced into the same low-temperature refrigerant heat exchanger 21 or high-temperature refrigerant heat exchanger 22. The refrigerants of different heat pump units 33 are mixed in the low-temperature refrigerant heat exchanger 21 or high-temperature refrigerant heat exchanger 22 to achieve the unification of the refrigerant temperature and pressure, reducing the fluctuations that may be caused by the separate control of the heat exchanger for each heat pump unit 33, improving the operating efficiency and stability of the entire system, and combining multiple low-temperature or high-temperature refrigerant heat exchangers 22 into an integrated unit can simplify the system structure, reduce the number of components, improve the compactness and reliability of the device, reduce the floor area occupied by the equipment, and improve the space utilization rate.

[0055] Others are the same as Embodiment 1 and will not be elaborated here.

[0056] Embodiment 4

[0057] As Figure 2 As shown, different from Embodiment 1: The chilled water circuit 6 is connected to the surface cooler, and the surface cooler exchanges heat with the electrodes in the heat dissipation area through air. The chilled water still maintains a relatively low temperature after passing through the low-temperature heat exchanger 12, while the electrodes have a relatively high temperature after being removed from the coating oven 41 and need to be cooled. Therefore, in this application, by setting the surface cooler, when the air passes through the surface cooler, circulating dehumidified air can be produced, and the high-temperature battery electrodes are cooled in the heat dissipation area with the circulating dehumidified cold air as the medium to recover the heat dissipated by the battery electrodes, thereby reducing waste heat emissions and reducing the operating energy consumption of the system. Moreover, quickly cooling the electrodes can prevent the electrodes from staying at a high temperature for too long, resulting in material degradation or performance loss, ensuring the quality of the electrodes, shortening the production cycle, and quickly cooling can reduce the waiting time from drying to the next process, improving production efficiency.

[0058] Others are the same as Embodiment 1 and will not be elaborated here. The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A thermal balance system for an NMP coating recovery device, characterized in that: It includes an NMP recovery module (1), a heat pump system module (2), a heat balance module (3), and a coating oven module (4) connected in sequence. Among them, the coating oven module (4), the heat balance module (3), and the heat pump system module (2) are connected in sequence to form a heat medium water balance loop (5). The heat pump system module (2) is used to convert the low-grade heat flowing out of the NMP recovery module (1) into high-grade heat, and the heat balance module (3) is used to summarize, store, and balance the temperature of the high-grade heat converted by the heat pump system module (2).

2. The thermal balance system for the NMP coating recovery device according to claim 1, characterized in that: The coating oven module (4) includes a coating oven (41), a circulation fan (42), and a high-temperature heat exchanger (43). The heat balance module (3) includes a hot water pump (31) and a hot water tank (32). The heat pump system module (2) includes a low-temperature refrigerant heat exchanger (21), a high-temperature refrigerant heat exchanger (22), a chiller (24), and a heat pump unit (23). The heat medium water balance loop (5) starts from the high-temperature refrigerant heat exchanger (22), passes through the hot water tank (32), the high-temperature heat exchanger (43), and the hot water pump (31) in sequence, and then returns to the high-temperature refrigerant heat exchanger (22).

3. The thermal balance system for the NMP coating recovery device according to claim 2, wherein: Multiple sets of the heat pump units (23) are provided, and the heat medium water flowing through the heat pump units (23) all flows into the same hot water tank (32).

4. The thermal balance system for the NMP coating recovery device according to claim 2, characterized in that: The heat pump system module (2) is connected to the NMP recovery module (1) to form a chilled water circuit (6), and the coating oven module (4) is connected to the NMP recovery module (1) to form a gas circulation circuit (7).

5. The thermal balance system for the NMP coating recovery device according to claim 4, characterized in that: The NMP recovery module (1) includes an air-air heat exchanger (11), a low-temperature heat exchanger (12), and an exhaust fan (13). The gas circulation circuit (7) starts from the coating oven (41), passes through the exhaust fan (13), the air-air heat exchanger (11), the low-temperature heat exchanger (12), the air-air heat exchanger (11), the circulation fan (42), and the high-temperature heat exchanger (43) in sequence, and finally returns to the coating oven (41). The chilled water circuit (6) starts from the low-temperature refrigerant heat exchanger (21), passes through the chiller (24), a chilled water pump (25), and the low-temperature heat exchanger (12) in sequence, and then flows back to the low-temperature refrigerant heat exchanger (21).

6. The thermal balance system for the NMP coating recovery device according to claim 2, wherein: There are multiple heat pump units (23), and multiple heat pump units (23) are all connected to the same low-temperature refrigerant heat exchanger (21) and the same high-temperature refrigerant heat exchanger (22).

7. The thermal balance system for the NMP coating recovery device according to claim 5, characterized in that: The chilled water circuit (6) is connected to a surface cooler (61), and the surface cooler (61) exchanges heat with the pole pieces in the heat dissipation area (62) through air.

8. The thermal balance system for the NMP coating recovery device according to claim 5, characterized in that: An auxiliary heater (44) is also connected to the gas circulation circuit (7).

9. The thermal balance system for the NMP coating recovery device according to claim 5, wherein: The coating oven (41) has multiple sections, and each section of the coating oven (41) is connected to the gas circulation circuit (7) and the heat medium water balance loop (5).

10. The thermal balance system for the NMP coating recovery device according to claim 1, characterized in that: It also includes an exhaust gas treatment system (14).

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