Energy-saving device for recovering and reusing waste heat of high-efficiency air compressor

Abstract

This application relates to the field of energy recycling technology, and in particular to a high-efficiency air compressor waste heat recovery and reuse energy-saving device. It includes an air compressor, an oil heat recovery system, a compressed air heat recovery system, and a heat terminal system. The oil heat recovery system includes a first thermal control valve, an oil filter, a heat exchanger, and a second thermal control valve. The oil inlet pipes of the first thermal control valve, the oil filter, and the heat exchanger, the second thermal control valve, and the oil inlet of the air compressor are sequentially connected by pipes, forming a circulation system. The compressed air heat recovery system includes a gas conveying device, an air filter, a dehumidifier, and a gas heating unit. The compressed air output end of the air compressor is equipped with the gas conveying device. The gas inlet ends of the gas conveying device, the air filter, the dehumidifier, and the gas heating unit are sequentially connected by pipes. The hot water output end is connected to the heat terminal system. This application has the effect of improving waste heat recovery efficiency and reducing investment costs.

Description

Technical Field

[0001] This application relates to the field of energy recycling technology, and in particular to an energy-saving device for the recovery and reuse of waste heat from an air compressor. Background Technology

[0002] Air compressors are commonly used equipment in industrial production. During operation, they generate large amounts of high-temperature oil and compressed air, consuming significant amounts of electricity and heat. Much of this heat from the oil and compressed air is directly released into the environment, resulting in substantial energy waste. Research has found that approximately 75% of the heat energy in oil-injected screw compressors is consumed in the hot oil cooling circuit and directly carried away by the cooler; this waste heat is not effectively utilized. Existing waste heat recovery technologies suffer from low recovery efficiency, poor heat transfer, and significant equipment modifications, failing to fully utilize the waste heat generated by air compressors and leading to persistently high energy costs for businesses. Utility Model Content

[0003] In order to improve the efficiency of waste heat recovery and reduce investment costs, this application provides an energy-saving device for waste heat recovery and reuse of air compressors.

[0004] The high-efficiency air compressor waste heat recovery and reuse energy-saving device provided in this application adopts the following technical solution:

[0005] A high-efficiency air compressor waste heat recovery and reuse energy-saving device includes an air compressor, an oil heat recovery system, a compressed air heat recovery system, and a heat terminal system. The oil heat recovery system includes a thermal control valve one, an oil filter, a heat exchanger, and a thermal control valve two. The thermal control valve one is connected to the high-temperature oil output end of the air compressor via a pipeline. The oil inlet pipelines of the thermal control valve one, oil filter, and heat exchanger, the thermal control valve two, and the oil inlet end of the air compressor are sequentially connected via pipelines to form a circulation system. The compressed air heat recovery system includes a gas conveying device, an air filter, a dehumidifier, and a gas heating unit. The compressed air output end of the air compressor is equipped with a gas conveying device. The gas heating unit is equipped with a cold water input end, a hot water output end, a gas input end, and a gas output end. The gas conveying device, air filter, dehumidifier, and gas heating unit are sequentially connected via pipelines. The hot water output end is connected to the heat terminal system.

[0006] By adopting the above technical solution, during air compressor operation, the hot oil in the hot oil cooling circuit enters the heat exchanger of the oil heat recovery system. Inside the heat exchanger, the heat from the hot oil is transferred to the cold water, causing the cold water to heat up and form hot or warm water. The hot or warm water is then transported to the heat-using terminal system through pipelines. Meanwhile, compressed air is transported to the gas heating unit through the gas conveying equipment in the compressed air heat recovery system. Inside the gas heating unit, the heat from the compressed air is transferred to the cold water, similarly causing the cold water to heat up and form hot or warm water. The hot or warm water is then transported to the heat-using terminal system through the hot water output terminal. This achieves the recovery of a large amount of waste heat energy generated by the air compressor, improving the overall energy utilization rate.

[0007] Furthermore, this application recovers waste heat without altering the original performance and operational stability of the air compressor. It does not require large-scale modifications to the air compressor or replacement of key components. Heat recovery and utilization can be achieved simply by connecting a waste heat recovery device and a heat transmission pipeline, reducing implementation difficulty and investment costs. Moreover, the modification process is simple and convenient, with minimal impact on the normal production of enterprises.

[0008] Optionally, the gas heating unit includes an outer storage tank, an inner storage tank, and a spiral tube. The inner storage tank is disposed inside the outer storage tank and is coaxially and fixedly connected to the outer storage tank. The spiral tube is spirally arranged along the outer circumference of the inner storage tank and is fixed to the inner storage tank along the spiral direction. Both the outer and inner storage tanks are connected to a cold water inlet and a hot water outlet. One end of the spiral tube is connected to a gas inlet, which is connected to the compressed air outlet of an air compressor. The other end of the spiral tube is connected to a gas outlet.

[0009] By adopting the above technical solution, a spiral tube is placed between the outer and inner storage tanks. Compressed air swirls inside the spiral tube, and its heat is transferred to the cold water stored in the outer and inner storage tanks during the swirling process, thereby raising the temperature of the cold water to form warm or hot water. This design can not only effectively reduce heat loss during the transfer process, but also enable the cold water to heat up rapidly, improve the waste heat recovery efficiency, and enhance the heat transfer effect.

[0010] Optionally, the gas output end of the spiral tube is provided with a gas return pipe, the gas return pipe is connected to the gas input end of the spiral tube, and a switch valve is provided on the gas return pipe.

[0011] By adopting the above technical solution, a gas return pipe is set at the gas output end of the spiral tube. After the compressed gas swirls once inside the spiral tube, it can re-enter the gas input end of the spiral tube through the gas return pipe. After multiple cycles, the switch valve is opened to discharge the gas outdoors, thereby achieving complete recovery of the waste heat of the compressed air and reducing heat waste.

[0012] Optionally, each of the conveying pipes has a slope, and each of the pipes is equipped with an exhaust valve.

[0013] By adopting the above technical solution, setting the delivery pipeline with a certain slope, and venting air regularly, it can be ensured that hot or warm water can be smoothly delivered to the heating terminal system.

[0014] Optionally, the outer surface of the outer storage tank is provided with an insulation shell.

[0015] By adopting the above technical solution, a heat insulation shell is set on the outer surface of the outer storage tank, which can effectively reduce heat loss.

[0016] Optionally, each of the conveying pipes is wrapped with an insulation layer.

[0017] By adopting the above technical solution, each conveying pipeline is wrapped with insulation material to form an insulation layer, which can reduce the loss of heat during the transmission process.

[0018] Optionally, each of the pipes is equipped with a temperature sensor and a flow sensor.

[0019] By adopting the above technical solution, temperature and flow data can be monitored in real time through sensors, and the data can be transmitted to the control system, thereby enabling operators to know the actual operating conditions in a timely manner and reducing safety hazards.

[0020] Optionally, the heat terminal system includes a boiler water preheating unit and a heating unit, wherein the boiler water preheating unit is connected to the outlet pipe of the outer storage tank and the heating unit is connected to the outlet pipe of the inner storage tank.

[0021] By adopting the above technical solution, the recovered hot water is introduced into the boiler feedwater pipe and preheated before entering the boiler. Preheating increases the boiler feedwater temperature, reducing the energy required for boiler heating and thus lowering the consumption of fuels such as natural gas. The recovered hot or warm water then exchanges heat with the circulating water in the heating system, raising its temperature and providing warm air to the room to meet winter heating needs.

[0022] In summary, this application includes at least one of the following beneficial technical effects:

[0023] 1. By installing an oil heat recovery system and a compressed air heat recovery system at the high-temperature oil output end and compressed air output end of the air compressor, respectively, when the air compressor is running, hot oil enters the heat exchanger of the oil heat recovery system, where its heat is transferred to cold water. Meanwhile, compressed air is transported to a gas heating unit via a gas conveying device in the compressed air heat recovery system, where its heat is transferred to the cold water. Both processes heat the cold water to form hot or warm water, which is then transported to the heat-using terminal system via pipelines. This achieves the recovery of a large amount of waste heat energy generated by the air compressor, improving the overall energy utilization rate. Furthermore, this application recovers waste heat without affecting the normal operation of the air compressor, eliminating the need for complex modifications to the air compressor and reducing implementation difficulty and cost.

[0024] 2. By placing a spiral tube between the outer and inner storage tanks, compressed air circulates within the spiral tube.

[0025] The heat is transferred to the cold water stored in the outer and inner tanks during the swirling process, thereby warming the cold water to form warm or hot water. This design not only effectively reduces heat loss during the transfer process, but also enables the cold water to heat up rapidly, improving the waste heat recovery efficiency and enhancing the heat transfer effect.

[0026] 3. By installing an insulation shell on the outer surface of the outer storage tank, heat loss can be effectively reduced. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of an energy-saving device for high-efficiency air compressor waste heat recovery and reuse in this application.

[0028] Figure 2 This is a cross-sectional view of the gas heating unit in this application.

[0029] Explanation of reference numerals in the attached diagram: 1. Air compressor; 2. Oil heat recovery system; 21. Thermal control valve one; 22. Oil filter; 23. Heat exchanger; 24. Thermal control valve two; 3. Compressed air heat recovery system; 31. Gas conveying equipment; 32. Air filter; 33. Dehumidifier; 34. Gas heating unit; 341. External storage tank; 342. Internal storage tank; 343. Spiral tube; 344. Gas return pipeline; 345. Switch valve; 4. Heat terminal system; 41. Boiler water preheating unit; 42. Radiator heating unit; 5. Exhaust valve; 6. Temperature sensor; 7. Flow sensor. Detailed Implementation

[0030] The following is in conjunction with the appendix Figure 1-2 This application will be described in further detail.

[0031] This application discloses an energy-saving device for waste heat recovery and reuse of air compressors. (Refer to...) Figure 1 The high-efficiency air compressor waste heat recovery and reuse energy-saving device includes an air compressor 1, an oil heat recovery system 2, a compressed air heat recovery system 3, and a heat terminal system 4. The oil heat recovery system 2 includes a thermal control valve 21, an oil filter 22, a heat exchanger 23, and a thermal control valve 24. The thermal control valve 21 is connected to the high-temperature oil output end of the air compressor 1 through a pipeline. The oil pipes of the thermal control valve 21, the oil filter 22, and the heat exchanger 23, the thermal control valve 24, and the oil inlet end of the air compressor 1 are connected in sequence through pipelines to form a circulation system. The water inlet end of the water pipe of the heat exchanger 23 is supplied with cold water, and the outlet end is connected to the gas heating unit 34, so that the heated warm water or hot water enters the gas heating unit 34 as a heat source for storage.

[0032] Furthermore, temperature control is crucial during the operation of air compressor 1. If the temperature is too high, the lubricating oil may age and coke, affecting lubrication and sealing performance, leading to air compressor 1 malfunction. Conversely, if the temperature is too low, the lubricating oil may emulsify and deteriorate, similarly affecting lubrication. Therefore, maintaining air compressor 1 within a reasonable temperature range is essential. Thermal control valve 1 21 and thermal control valve 24, as temperature control valves, sense temperature changes through temperature sensing elements and control the valve opening to regulate the hot oil flow and achieve precise temperature control.

[0033] The compressed air heat recovery system 3 includes a gas conveying device 31, an air filter 32, a dehumidifier 33, and a gas heating unit 34. The compressed air output end of the air compressor 1 is equipped with the gas conveying device 31. The gas heating unit 34 has a cold water input end, a hot water output end, a gas input end, and a gas output end. The gas input ends of the gas conveying device 31, air filter 32, dehumidifier 33, and gas heating unit 34 are connected sequentially via pipelines. The hot water output end is connected to the general-purpose heat terminal system 4. After being output from the compressor, the compressed air is conveyed to the gas heating unit 34 via the gas conveying device 31. During this process, the compressed air passes through the air filter 32 and dehumidifier 33 sequentially for dust removal, sterilization, and dehumidification, ensuring the cleanliness and dryness of the compressed air. The purified and dried gas enters the gas heating unit 34, where the heat of the gas is transferred to the cold water, raising the temperature to form warm or hot water. The warm or hot water is then delivered to the heat terminal system 4, thereby realizing the recovery and utilization of the heat from the compressed air.

[0034] To ensure smooth transport, each transport pipeline has a certain slope and is equipped with an exhaust valve 5 to promptly release gas from the pipeline. To facilitate real-time monitoring of the transport status in each transport loop, each pipeline is equipped with a temperature sensor 6 and a flow sensor 7 for timely data collection. Each transport pipeline is wrapped with an insulation layer to effectively reduce heat loss during transport.

[0035] Reference Figure 2 The gas heating unit 34 includes an outer storage tank 341, an inner storage tank 342, and a spiral tube 343. The inner storage tank 342 is disposed inside the outer storage tank 341 and is coaxially and fixedly connected to the outer storage tank 341. There is a certain space between the outer storage tank 341 and the inner storage tank 342. The spiral tube 343 is spirally arranged along the outer circumference of the inner storage tank 342 and is fixed on the inner storage tank 342 along the spiral direction. Both the outer storage tank 341 and the inner storage tank 342 are connected to a cold water inlet and a hot water outlet. Cold water is introduced into both the outer storage tank 341 and the inner storage tank 342. One end of the spiral tube 343 is connected to the gas inlet, which is connected to the compressed air outlet of the air compressor 1. The other end of the spiral tube 343 is connected to the gas outlet. When hot air swirls inside the spiral tube 343, it can heat the cold water in the outer storage tank 341 and the inner storage tank 342. The water outlet of the heat exchanger 23 is connected to the outer storage tank 341 of the gas heating unit 34, so that the warm water after heat exchange is introduced into the outer storage tank 341.

[0036] To reduce heat loss over time, the outer surface of the outer storage tank 341 is provided with an insulation shell, which can prevent the water temperature from dropping over a longer period of time.

[0037] Refer to and Figure 2 To allow the gas to swirl multiple times, a gas return pipe 344 is provided at the gas output end of the spiral tube 343. The gas return pipe 344 is connected to the gas input end of the spiral tube 343, and a switch valve 345 is installed on the gas return pipe 344. Since the gas temperature does not decrease after just one swirling within the spiral tube 343, it can swirl multiple times to recover as much heat as possible. After the gas has swirld multiple times, the switch valve 345 is opened to directly discharge the low-temperature gas.

[0038] The heating terminal system 4 includes a boiler water preheating unit 41 and a heating unit 42. Since the water temperature in the outer storage tank 341 is lower than that in the inner storage tank 342, the boiler water preheating unit 41 is connected to the outlet pipe of the outer storage tank 341 to preheat the water in the boiler. The heating unit 42 is connected to the outlet pipe of the inner storage tank 342 to directly provide heating to the user terminal, providing heating in winter and hot water in non-winter seasons.

[0039] This application applies to the air-cooled, oil-injected screw air compressor in the refining workshop of the lithium salt plant, but with appropriate adjustments, it can also be applied to other types of air compressors and industrial enterprises of different sizes. In practical applications, the operating parameters of the waste heat recovery device can be flexibly adjusted according to the enterprise's heat demand and the operating status of the air compressor to ensure that the system is always in a state of high-efficiency operation.

[0040] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A high-efficiency air compressor waste heat recovery and reuse energy-saving device, characterized in that: It includes an air compressor (1), an oil heat recovery system (2), a compressed air heat recovery system (3), and a heat terminal system (4). The oil heat recovery system (2) includes a thermal control valve (21), an oil filter (22), a heat exchanger (23), and a thermal control valve (24). The thermal control valve (21) is connected to the high-temperature oil output end of the air compressor (1) through a pipeline. The oil pipes of the thermal control valve (21), the oil filter (22), the heat exchanger (23), the thermal control valve (24), and the oil inlet end of the air compressor (1) are connected in sequence through pipelines to form a circulation system. The compressed air heat recovery system (3) includes a gas conveying device (31), an air filter (32), a dehumidifier (33), and a gas heating unit (34). The compressed air output end of the air compressor (1) is equipped with a gas conveying device (31). The gas heating unit (34) is equipped with a cold water input end, a hot water output end, a gas input end, and a gas output end. The gas conveying device (31), the air filter (32), the dehumidifier (33), and the gas heating unit (34) are connected in sequence through pipelines. The hot water output end is connected to a general heating terminal system (4).

2. The high-efficiency air compressor waste heat recovery and reuse energy-saving device according to claim 1, characterized in that: The gas heating unit (34) includes an outer tank (341), an inner tank (342), and a spiral tube (343). The inner tank (342) is located inside the outer tank (341) and is coaxially fixedly connected to the outer tank (341). The spiral tube (343) is spirally arranged along the outer circumference of the inner tank (342) and fixed on the inner tank (342) along the spiral direction. Both the outer tank (341) and the inner tank (342) are connected to the cold water inlet and the hot water outlet. One end of the spiral tube (343) is connected to the gas inlet, which is connected to the compressed air outlet of the air compressor (1). The other end of the spiral tube (343) is connected to the gas outlet.

3. The high-efficiency air compressor waste heat recovery and reuse energy-saving device according to claim 2, characterized in that: The gas output end of the spiral tube (343) is provided with a gas return pipe (344), which is connected to the gas input end of the spiral tube (343). A switch valve (345) is provided on the gas return pipe (344).

4. The high-efficiency air compressor waste heat recovery and reuse energy-saving device according to claim 1, characterized in that: Each of the pipes has a slope and each of the pipes is equipped with an exhaust valve (5).

5. The high-efficiency air compressor waste heat recovery and reuse energy-saving device according to claim 2, characterized in that: The outer surface of the outer storage tank (341) is provided with an insulation shell.

6. The high-efficiency air compressor waste heat recovery and reuse energy-saving device according to claim 1, characterized in that: Each of the pipes is covered with an insulation layer.

7. The high-efficiency air compressor waste heat recovery and reuse energy-saving device according to claim 1, characterized in that: Each of the pipes is equipped with a temperature sensor (6) and a flow sensor (7).

8. The high-efficiency air compressor waste heat recovery and reuse energy-saving device according to claim 1, characterized in that: The heat terminal system (4) includes a boiler water preheating unit (41) and a heating unit (42). The boiler water preheating unit (41) is connected to the outlet pipe of the outer storage tank (341), and the heating unit (42) is connected to the outlet pipe of the inner storage tank (342).

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