An air compression pre-treatment system

Abstract

The present invention provides an air compression pre-treatment system, comprising a dehumidification air duct: the dehumidification air duct is located upstream of the air compressor, the dehumidification air duct comprises a dehumidification wheel, a heat recovery module: the heat recovery module comprises a first regeneration air duct, a heat exchanger and the air compressor are connected in series upstream of the first regeneration air duct, and a regulating air duct: the regulating air duct and the dehumidification air duct constitute a circulation air duct, and when the air compressor is working in variable frequency, the air volume in the dehumidification air duct and the regulating air duct is dynamically balanced. The present invention reduces the air compressor suction temperature and humidity through the air compression pre-treatment system, changes the operating range of the air compressor, reduces operating energy consumption, reduces maintenance costs, reduces the investment cost of post-processing equipment, recovers the high-temperature exhaust heat of the air compressor as a regeneration heat source input, and controls and switches the regulating air duct, thereby reducing the operating energy consumption of the air compression pre-treatment system, making it more stable and energy-saving.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of air treatment, and in particular to an air compression pre-treatment system. Background Art

[0002] Compressed air is the second largest power source in industry and plays a vital role in the field of industrial production. Moreover, with the upgrading of industrial structure, industrial production is shifting towards a more intelligent and precise production mode. Not only is the application of compressed air more extensive, but the quality requirements for compressed air are also higher. Ultra-low pressure dew point, clean and oil-free compressed air has become the first choice, which requires not only the air compressor to use oil-free air compressors, but also the post-processing equipment to use cold water or cold dryers, or even suction dryers. However, due to the nature of compressed air and the energy conversion characteristics of the air compressor itself, the energy consumption of equipment using air compressors plus post-processing is very high and the energy utilization efficiency is very low.

[0003] The cold dryer cannot utilize the waste heat of the air compressor. The high-temperature compressed air and high-temperature lubricating oil are discharged in the air cooler in the form of heat energy, which is not environmentally friendly. The working environment of the cold dryer is limited. The cold dryer cannot operate normally in an environment where the temperature is too low (below 0°C) or too high (above 38°C), the ventilation conditions are poor, and the air is polluted. The power consumption of the cold dryer is high. When the intake temperature increases by 5°C, the power consumption increases by 35%.

[0004] The dryer is large in size and complex in structure. It has two adsorbent material tanks and a conveying device. The pressure dew point is unstable. Problems such as uneven airflow distribution, adsorbent type, filling temperature, and "tunnel effect" can lead to unstable pressure dew point. The energy consumption is high, the adsorbent has poor instantaneous desorption ability, and desorption requires high energy consumption. The pressure loss is relatively large. The compressed air passes through layers of adsorbent, resulting in large pressure loss. The compressed air quality is poor, and adsorbent dust is easily mixed into the compressed air, reducing the quality of the compressed air.

[0005] An air compressor is a device that compresses air through a compressor and converts mechanical energy into internal energy. However, in the air compression process, a large degree of mechanical energy is directly converted into heat energy, which causes the temperature of the compressed air to rise. The high temperature of compressed air is not good for the compressor. Due to this, the pressure of the first-stage compressor outlet will not be very high, and the high-temperature exhaust gas needs to be cooled before the second-stage compression or even the third-stage compression can be carried out. After cooling, it is discharged and the dry compressed air is obtained through the post-processing equipment and sent to the gas-using equipment. The energy consumption of the entire system is relatively high, and the energy conversion efficiency is not good. When the intake temperature and humidity are relatively high, it will also have an adverse effect on the operation of the compressor. Therefore, the pre-treatment of the compressor intake is particularly important. Summary of the invention

[0006] In view of the above-mentioned defects of air compressor post-processing and the waste of heat energy of the air compressor itself, the present invention provides an air compression pre-processing system for air compressor intake pre-processing, comprising

[0007] Dehumidification air duct: The dehumidification air duct is located upstream of the air compressor, and the dehumidification air duct includes a dehumidification unit and a cooling unit. The dehumidification unit includes a dehumidification wheel, and the dehumidification wheel includes a regeneration area and a processing area.

[0008] Heat recovery module: The heat recovery module comprises a first regeneration air duct, wherein the first regeneration air duct is connected in series with a heat exchanger and the air compressor upstream, and the first regeneration air duct is connected to the regeneration zone downstream.

[0009] Adjusting air duct: The adjusting air duct and the dehumidifying air duct form a circulating air duct.

[0010] When the air compressor operates at variable frequency, the air volumes in the dehumidification air duct and the regulating air duct are dynamically balanced.

[0011] Preferably, a three-way valve B is provided at the outlet of the dehumidification air duct, one end of the three-way valve B is connected to the inlet of the regulating air duct, and a three-way valve A is provided at the inlet of the dehumidification air duct, one end of the three-way valve A is connected to the outlet of the regulating air duct.

[0012] Preferably, when the operating frequency of the air compressor decreases and the air intake volume decreases, the three-way valve A and the third-way valve B are adjusted to increase the air volume entering the regulating air duct, and the air volume of the dehumidification air duct remains unchanged.

[0013] Preferably, there is one regeneration zone, which is the first regeneration zone. The first regeneration air duct includes a first heat coil. The water inlet end of the first heat coil is connected to a high-temperature water tank group. The water outlet end of the first heat coil is connected to a low-temperature water tank group. The temperature of the high-temperature water in the high-temperature water tank group is higher than the temperature of the low-temperature water in the low-temperature water tank group.

[0014] Preferably, the low-temperature water tank group is located upstream of the heat exchanger so that low-temperature water flows into the heat exchanger and exchanges heat in the heat exchanger, and the high-temperature water tank group is located downstream of the heat exchanger so that low-temperature water flows into the high-temperature water tank group after heat exchange in the heat exchanger.

[0015] Preferably, there are two regeneration zones, including a first regeneration zone and a second regeneration zone, the second regeneration zone is connected to a second regeneration air duct, the inlet of the second regeneration air duct is connected to the dehumidification air duct and is located downstream of the dehumidification wheel.

[0016] Preferably, the second regeneration air duct comprises a second heat coil, a water inlet end of the second heat coil is connected to a high-temperature water tank group, a water outlet end of the second heat coil is connected to a low-temperature water tank group, and the second heat coil is connected in parallel with the first heat coil.

[0017] Preferably, when the dehumidification wheel rotates, it turns from the first regeneration zone to the second regeneration zone, and the temperature of the second regeneration zone is higher than the temperature of the first regeneration zone.

[0018] Preferably, an electric heater is also provided on the second regeneration air duct for further heating the air in the second regeneration air duct after being heated by the second heat coil.

[0019] Preferably, the cooling unit comprises a front surface cooler located upstream of the dehumidification wheel and a rear surface cooler located downstream of the dehumidification wheel.

[0020] Beneficial effects of the present invention: This technical solution reduces the air compressor suction temperature and humidity through the air compression pre-treatment system, changes the operating range of the air compressor, reduces the operating power, and reduces maintenance costs; it can also reduce the investment cost and operating energy consumption of the post-processing equipment dryer, and improve the quality and stability of the gas quality; through the high-temperature exhaust heat recovery of the air compressor as the regeneration heat source input of the pre-treatment equipment, coupled with the control and switching of the regulating air duct of the air compression pre-treatment system, the operating energy consumption of the air compression pre-treatment system is greatly reduced, and the performance delay of the air compression pre-treatment system due to changes in the air compressor gas consumption is reduced, making the entire system more stable and energy-saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of an air compression pre-treatment system according to Embodiment 1 of the present invention;

[0022] Figure 2 is a schematic diagram of an air compression pre-treatment system according to a second embodiment of the present invention;

[0023] Figure 3 Schematic diagram of an air compression pre-treatment system according to Embodiment 3 of the present invention;

[0024] In the figure,

[0025] 1. Dehumidification air duct; 2. First regeneration air duct; 3. Adjustment air duct; 4. Heat exchanger; 5. Air compressor; 6. First regeneration zone; 7. Three-way valve A; 8. Three-way valve B; 9. Front surface cooler; 10. Rear surface cooler; 11. First heat coil; 12. High-temperature water pump; 13. High-temperature water tank; 14. Low-temperature water tank; 15. Low-temperature water pump; 16. Second heat coil; 17. Electric heater; 18. Second regeneration zone. DETAILED DESCRIPTION

[0026] The present invention is described in detail below in conjunction with the accompanying drawings. The description in this part is only exemplary and explanatory and should not have any limiting effect on the scope of protection of the present invention.

[0027] It should be noted that the terms "upstream" and "downstream" are defined in terms of relative positions relative to the flow direction of air or water flow, the terms "high temperature" and "low temperature" are relative heights, not absolute heights, and the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0028] Figure 1 It is a schematic diagram of the first embodiment of the present invention. The present invention provides an air compression pre-treatment system for air intake pre-treatment of an air compressor 5, comprising a dehumidification air duct 1, a heat recovery module and a regulating air duct 3.

[0029] The dehumidification air duct 1 is located upstream of the air compressor 5, and the air to be treated is dehumidified and cooled before being input into the air compressor 5. The dehumidification air duct 1 includes a dehumidification unit and a cooling unit. The dehumidification unit includes a dehumidification wheel. The dehumidification wheel includes a regeneration area and a treatment area. The air to be treated is filtered through primary filtration to remove large particles of impurities and dust. The air flows into the dehumidification air duct 1 under the push of the fan. When passing through the treatment area of ​​the dehumidification wheel, the water vapor in the air is adsorbed, thereby becoming dry. The treatment area of ​​the dehumidification wheel adsorbs the water vapor and then transfers to the regeneration area. The high-temperature gas is used for the regeneration area. The dehumidification zone is desorbed so that the dehumidification wheel circulates; the dehumidification air duct 1 includes a cooling unit, which can be a surface cooler or other refrigeration equipment. A plurality of cooling units can be provided. A front surface cooler 9 is provided upstream of the dehumidification wheel. The low-temperature air to be treated can improve the dehumidification efficiency of the dehumidification wheel. A rear surface cooler 10 can be provided downstream of the dehumidification wheel to further cool the dehumidified air. The low-temperature dry air enters the air compressor 5, which can reduce the energy consumption of the air compressor 5, reduce the maintenance cost of the air compressor 5, and reduce the operating cost of the post-processing equipment.

[0030] Heat recovery module: The heat recovery module comprises a first regeneration air duct 2, wherein the heat exchanger 4 and the air compressor 5 are connected in series upstream of the first regeneration air duct 2, and the regeneration zone is connected downstream of the first regeneration air duct 2. A large amount of heat energy generated by the air compressor 5 when working is recovered to the heat exchanger 4. When the air passes through the heat exchanger 4, it exchanges heat with the recovered heat energy, and the air temperature rises. The high-temperature air is transported to the dehumidification wheel regeneration zone through the first regeneration air duct 2 to regenerate the dehumidification wheel. The regenerated high-temperature air utilizes the heat energy of the air compressor 5, and no additional heating source is required to heat the air, which effectively saves energy and reduces pollution to the environment.

[0031] Adjusting air duct 3: The adjusting air duct 3 and the dehumidifying air duct 1 form a circulating air duct. When the air compressor 5 is working at variable frequency, the air volume in the dehumidifying air duct 1 and the adjusting air duct 3 is dynamically balanced. A three-way valve B8 is arranged at the outlet of the dehumidifying air duct 1. One end of the third-way valve B8 is connected to the inlet of the adjusting air duct 3. The third-way valve B8 divides the airflow coming out of the dehumidifying air duct 1 into two streams, one stream flows into the adjusting air duct 3, and the other stream flows into the downstream air compressor 5. A three-way valve A7 is arranged at the inlet of the dehumidifying air duct 1. One end of the three-way valve A7 is connected to the outlet of the adjusting air duct 3. The three-way valve A7 mixes the airflow flowing out of the adjusting air duct 3 with the air to be treated before passing through the blower Entering the dehumidification air duct 1, when the operating frequency of the air compressor 5 decreases and the air intake volume decreases, the three-way valve A7 and the third-way valve B8 are adjusted to increase the air volume entering the regulating air duct 3 and reduce the amount of air to be processed; when the operating frequency of the air compressor 5 becomes higher and the air intake volume increases, the three-way valve A7 and the third-way valve B8 are adjusted to reduce the air volume entering the regulating air duct 3 and increase the amount of air to be processed. Regardless of how the operating frequency of the air compressor 5 changes, the air volume of the dehumidification air duct 1 remains unchanged, avoiding adjustments to a series of related components such as the dehumidification wheel and the surface cooler when the air volume of the dehumidification air duct 1 changes. These adjustments will increase the system response time and increase instability when the air compressor 5 frequently changes frequency. The air compression pretreatment system provided by the present invention ensures that under different working conditions, the working frequency of the air compressor 5 is constantly changing, and the air intake volume of the air compressor 5 is constantly changing. This can reduce the operating energy consumption of the air compression pretreatment system when the air consumption of the air compressor 5 is reduced, and can also reduce the performance delay of the air compression pretreatment system when the air consumption of the air compressor 5 is increased.

[0032] When there is only one air compressor 5, the heat recovery structure is relatively simple and the system stability is guaranteed. However, when there are multiple air compressors 5 working, it is difficult to recover and collect the heat energy of all air compressors 5 together, and the system stability is poor. Figure 21 is a schematic diagram of the second embodiment of the present invention. For the sake of simplicity, the parts repeated in the first embodiment are not repeated. In the second embodiment, a high-temperature water tank group and a low-temperature water tank group are added. The first regeneration air duct 2 includes a first heat coil 11. The water inlet end of the first heat coil 11 is connected to the high-temperature water tank group. The high-temperature water tank group includes a high-temperature water tank 13 and a high-temperature water pump 12. The water outlet end of the first heat coil 11 is connected to the low-temperature water tank group. The low-temperature water tank group includes a low-temperature water tank 14 and a low-temperature water pump 15. The high-temperature water in the high-temperature water tank 13 is pumped through the high-temperature water pump 12. The air flows into the first heat coil 11, and the air exchanges heat with the high-temperature water through the first heat coil 11. The air temperature rises, and the air flows to the dehumidification wheel regeneration area through the first regeneration air duct 2. The high-temperature water temperature decreases and flows into the low-temperature water tank 14. The low-temperature water tank group is located upstream of the heat exchanger 4, and the high-temperature water tank group is located downstream of the heat exchanger 4. The low-temperature water in the low-temperature water tank 14 flows into the heat exchanger 4 through the low-temperature water pump 15. The low-temperature water exchanges heat with the high-temperature compressed air of the air compressor 5, and the water temperature rises, and flows back into the high-temperature water tank 13, and the cycle repeats. This embodiment is particularly suitable for a working environment with multiple air compressors 5. The heat energy of multiple air compressors 5 is recovered and used as a regeneration heat source for the air compression pretreatment system, which greatly reduces the operating energy consumption of the pretreatment equipment and has high system stability.

[0033] In the second embodiment, there is only one dehumidification wheel regeneration zone. Figure 3 It is a schematic diagram of embodiment 3 of the present invention. In this embodiment, the dehumidification wheel includes a first regeneration zone 6 and a second regeneration zone 18, and the heat recovery module includes a second regeneration air duct. The inlet of the second regeneration air duct is connected to the dehumidification air duct 1 and is located downstream of the dehumidification wheel. A valve is provided at the inlet of the second regeneration air duct to control the amount of air flowing into the second regeneration air duct. The air flowing out of the dehumidification wheel treatment zone has moisture in the air adsorbed by the dehumidification wheel, the temperature rises, the dew point drops, and the air becomes dry air. Part of the treated air flows to the rear surface cooler 10, and after being cooled by the rear surface cooler 10, it flows to the air compressor 5, and the other part flows to the second regeneration air duct.

[0034] A second heat coil 16 is also provided on the second regeneration air duct, and the second heat coil 16 heats the air in the second regeneration air duct, and the heated air flows to the second regeneration zone 18. The water inlet end of the second heat coil 16 is connected to the high-temperature water tank group, and the water outlet end of the second heat coil 16 is connected to the low-temperature water tank group. The second heat coil 16 is connected in parallel with the first heat coil 11. The high-temperature water in the high-temperature water tank 13 can supply the first heat coil 11 and the second heat coil 16 at the same time. The low-temperature water after heat exchange between the first heat coil 11 and the second heat coil 16 is collected in the low-temperature water tank 14. The heat energy collected by the air compressor 5 can be supplied to multiple regeneration air ducts, further improving the dehumidification effect of the dehumidification wheel, improving the treatment effect of the air compression pre-treatment system, and reducing the operating energy consumption of the air compression pre-treatment system. In order to ensure the stability of the regeneration temperature in the second regeneration air duct, an electric heater 17 is also provided on the second regeneration air duct to further heat the air in the second regeneration air duct. In this embodiment, the dehumidification wheel has two regeneration zones, both of which are equipped with regeneration air ducts, and each regeneration air duct recovers heat energy from different angles, which not only improves the regeneration effect of the dehumidification wheel regeneration zone, but also fully recovers heat energy, improves the energy utilization rate, and reduces the operating energy consumption of the pre-treatment equipment. The second regeneration air duct structure in this embodiment is also applicable to the first embodiment.

[0035] In the prior art, post-processing uses a cold dryer and a desiccant. The power consumption of the cold dryer is high. When the inlet air temperature rises by 5°C, the power consumption increases by 35%. The adsorbent of the desiccant has poor instantaneous desorption ability, and desorption requires very high energy consumption. The air compression pre-treatment system starts with pre-treatment to adjust the temperature and humidity of the air entering the air compressor 5, and then ensures the temperature and humidity of the air output by the air compressor 5, so that when the air discharged from the air compressor 5 enters the post-processing again, the pressure dew point and energy consumption problems of the cold dryer and the desiccant are fundamentally solved.

[0036] The above-described embodiments of the present invention do not constitute a limitation on the protection scope of the present invention. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. An air compression pre-treatment system, used for air compressor intake pre-treatment, characterized by: Include Dehumidification air duct: The dehumidification air duct is located upstream of the air compressor, and the dehumidification air duct includes a dehumidification unit and a cooling unit. The dehumidification unit includes a dehumidification wheel, and the dehumidification wheel includes a regeneration area and a processing area. Heat recovery module: The heat recovery module comprises a first regeneration air duct, wherein the first regeneration air duct is connected in series with a heat exchanger and the air compressor upstream, and the first regeneration air duct is connected to the regeneration zone downstream. Adjusting air duct: The adjusting air duct and the dehumidifying air duct form a circulating air duct. When the air compressor operates at variable frequency, the air volumes in the dehumidification air duct and the regulating air duct are dynamically balanced; A three-way valve B is arranged at the outlet of the dehumidification air duct, one end of the third-way valve B is connected to the inlet of the regulating air duct, and a three-way valve A is arranged at the inlet of the dehumidification air duct, one end of the three-way valve A is connected to the outlet of the regulating air duct.

2. The air compression pre-treatment system according to claim 1, characterized in that: When the operating frequency of the air compressor decreases and the air intake volume decreases, the three-way valve A and the third-way valve B are adjusted to increase the air volume entering the regulating air duct, and the air volume of the dehumidification air duct remains unchanged.

3. The air compression pre-treatment system according to claim 2, characterized in that: There is one regeneration zone, which is the first regeneration zone. The first regeneration air duct includes a first heat coil. The water inlet end of the first heat coil is connected to a high-temperature water tank group. The water outlet end of the first heat coil is connected to a low-temperature water tank group. The temperature of the high-temperature water in the high-temperature water tank group is higher than the temperature of the low-temperature water in the low-temperature water tank group.

4. The air compression pre-treatment system according to claim 3, characterized in that: The low-temperature water tank group is located upstream of the heat exchanger so that low-temperature water flows into the heat exchanger and exchanges heat in the heat exchanger. The high-temperature water tank group is located downstream of the heat exchanger so that low-temperature water flows into the high-temperature water tank group after heat exchange in the heat exchanger.

5. The air compression pre-treatment system according to claim 4, characterized in that: There are two regeneration zones, including a first regeneration zone and a second regeneration zone. The second regeneration zone is connected to a second regeneration air duct. The inlet of the second regeneration air duct is connected to the dehumidification air duct and is located downstream of the dehumidification wheel.

6. The air compression pre-treatment system according to claim 5, characterized in that: The second regeneration air duct includes a second heat coil, a water inlet end of the second heat coil is connected to a high-temperature water tank group, a water outlet end of the second heat coil is connected to a low-temperature water tank group, and the second heat coil is connected in parallel with the first heat coil.

7. The air compression pre-treatment system according to claim 5, characterized in that: When the dehumidification wheel rotates, it turns from the first regeneration zone to the second regeneration zone, and the temperature of the second regeneration zone is higher than the temperature of the first regeneration zone.

8. The air compression pre-treatment system according to claim 6, characterized in that: An electric heater is also provided on the second regeneration air duct to further heat the air in the second regeneration air duct after being heated by the second heat coil.

9. The air compression pre-treatment system according to any one of claims 1 to 6, characterized in that: The cooling unit includes a front surface cooler located upstream of the dehumidification wheel and a rear surface cooler located downstream of the dehumidification wheel.

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