An air separation precooling apparatus

Abstract

The utility model relates to a kind of air separation precooling equipment, including air cooling tower, and circulating water return main pipe is provided on air cooling tower, and cooling tower is provided on circulating water return main pipe, and first temperature sensor, first circulating water delivery branch pipe, first regulating valve and second circulating water delivery branch pipe are provided on circulating water return main pipe, water bath type vaporizer is provided on first circulating water delivery branch pipe, and water bath type vaporizer and second circulating water delivery branch pipe are communicated, and second temperature sensor, electric heater, first liquid flow sensor, second regulating valve, first booster pump and first filter are provided on first circulating water delivery branch pipe, and third temperature sensor and check valve are provided on second circulating water delivery branch pipe.Carrying heat energy of circulating water return water discharged by air cooling tower can be used for liquid oxygen vaporization.The utility model is convenient to use, with extensive market prospect.

Description

Technical Field

[0001] The utility model relates to the field of air separation equipment, in particular to an air separation pre-cooling device. Background Art

[0002] The air pre-cooling system is connected between the air filtering and compressing system and the molecular sieve purification system, and is mainly used to reduce the temperature and water content of the air entering the molecular sieve adsorber. The air temperature at the outlet of the air compressor unit is reduced from 88°C to about 15°C, and the saturated moisture in the air is reduced at the same time, which is beneficial to the purification of the molecular sieve, and can wash away dust, acidic media and the like in the air. The cold source of the air cooling tower in the air separation pre-cooling equipment mainly comes from circulating cooling water and chilled water. Among them, the normal temperature water from the water replenishing system can be cooled by the air cooling tower to become circulating cooling water (commonly known as return water, which can be recycled). Chilled water is obtained by re-cooling the return water of the air cooling tower in the water cooling tower. During the cooling process, the waste nitrogen or nitrogen that has been reheated after passing through the plate heat exchanger in the cold box is mainly required to participate in cooling the circulating water. Before the chilled water is used, the centralized collection of the chilled water needs to be completed at the bottom of the water cooling tower, and then it is pumped to the upper section of the air cooling tower by the chilled water pump, so as to realize the cooling and washing treatment of the compressed air. From practical experience, most air separation pre-cooling equipments use circulating water that is cooled by the water cooling tower and then enters the upper layer of the air cooling tower, so as to achieve the goals of water saving and consumption reduction.

[0003] The rectification system of the air separation gas equipment produces finished oxygen that is normally supplied to users. When the rectification system is under maintenance or the load cannot meet the user's demand, it is necessary to start the standby oxygen system supporting the air separation system for oxygen supply. In the prior art, the standby oxygen system supplies oxygen formed by vaporizing and reheating temporarily stored liquid oxygen. A water-bath vaporizer is commonly used in the standby oxygen system. The heat energy sources of the water-bath vaporizer mainly include electricity, hot water and steam. Therefore, according to different heating forms, it can be divided into electric heating water-bath vaporizers, steam heating water-bath vaporizers, and circulating water heating water-bath vaporizers. The circulating water return water discharged from the bottom of the air cooling tower absorbs a large amount of heat energy carried by the compressed air, and the circulating water return water carries a large amount of energy, while the use of a water-bath vaporizer has a rigid demand for water heat. If the energy carried by the circulating water return water discharged from the bottom of the air cooling tower is fully utilized in the liquid oxygen vaporization process, enterprises can reduce energy costs in this way, thereby reducing operating costs. Summary of the Utility Model

[0004] In view of the deficiencies in the prior art, the utility model provides an air separation pre-cooling device which can utilize the heat energy carried by the circulating water return water discharged from the air cooling tower for liquid oxygen vaporization, so as to overcome the defects in the prior art.

[0005] The technical solution adopted by this utility model is as follows: an air separation precooling device, including an air-cooling tower, wherein the air-cooling tower is provided with an inlet end of a circulating water return main pipe, and a cooling tower is provided at the outlet end of the circulating water return main pipe. A first temperature sensor, an inlet end of a first circulating water delivery branch pipe, a first regulating valve, and an outlet end of a second circulating water delivery branch pipe are sequentially arranged along the direction from the air-cooling tower to the cooling tower along the circulating water return main pipe. An inlet end of a water bath vaporizer circulating water channel is provided at the outlet end of the first circulating water delivery branch pipe. The outlet end of the water bath vaporizer circulating water channel is connected to the inlet end of the second circulating water delivery branch pipe. A second temperature sensor, an electric heater, a first liquid flow sensor, a second regulating valve, a first booster pump, and a first filter are sequentially arranged along the direction from near the water bath vaporizer to away from the water bath vaporizer along the first circulating water delivery branch pipe. A third temperature sensor and a one-way valve are provided on the second circulating water delivery branch pipe.

[0006] Preferably, a backup oxygen delivery pipe is provided at the outlet end of the liquid oxygen channel of the water bath vaporizer, and an air-cooled heat exchanger is provided on the backup oxygen delivery pipe. A liquid oxygen delivery pipe is provided at the inlet end of the liquid oxygen channel of the water bath vaporizer, and a liquid nitrogen pump, a second liquid flow sensor and an eighth regulating valve are provided on the liquid oxygen delivery pipe.

[0007] Preferably, the air-cooled tower above the circulating water return main pipe is provided with, in sequence along the direction from near to far from the circulating water return main pipe, an outlet end of a first air delivery pipe, a first packing layer, a cooling water nozzle, a second packing layer, a chilled water nozzle, a first wire mesh coalescer, and a second air delivery pipe. The cooling tower is provided with an inlet end of the circulating water delivery main pipe, and the outlet end of the circulating water delivery main pipe is connected to the cooling water nozzle. The circulating water delivery main pipe is provided with, in sequence along the direction from near to far from the cooling tower, a second filter, a second booster pump, a fourth temperature sensor, a third liquid flow sensor, and a third regulating valve.

[0008] Preferably, the main circulating water supply pipe between the fourth temperature sensor and the third liquid flow sensor is provided with the inlet end of a third circulating water supply branch pipe, the third circulating water supply branch pipe is provided with a fourth regulating valve, and the outlet end of the third circulating water supply branch pipe is provided with a water cooling tower. The water cooling tower is provided with, from bottom to top, the inlet end of the chilled water supply main pipe, the outlet end of the waste nitrogen gas supply pipe, the third packing layer, the circulating water nozzle, and the second wire mesh coalescer. The circulating water nozzle is connected to the outlet end of the third circulating water supply branch pipe, and the outlet end of the chilled water supply main pipe is connected to the chilled water nozzle.

[0009] Preferably, the chilled water main pipe is provided with a fifth regulating valve, a fourth liquid flow sensor, a fifth temperature sensor, the inlet end of the chilled water return branch pipe, the chilled water channel of the chiller unit, a third booster pump, a third filter, and a sixth temperature sensor in sequence along the direction from near the chilled water nozzle to far away from the chilled water nozzle. The chilled water main pipe is connected to the water cooling tower between the chilled water main pipe and the waste nitrogen gas transmission pipe and the outlet end of the chilled water return branch pipe. The chilled water return branch pipe is provided with a sixth regulating valve.

[0010] Preferably, a guide cylinder is provided inside the water-cooled tower below the nitrogen gas conveying pipe. The guide cylinder includes a guide section and a conveying section provided at the bottom end of the guide section. The top of the guide section is connected to the inner wall of the water-cooled tower. The guide section adopts an inverted frustum-shaped tubular structure. The diameter of the inner circle of the guide section gradually decreases as the height of the guide section decreases. The conveying section adopts a circular tubular structure. The inner diameter of the conveying section corresponds to the minimum diameter of the inner cavity of the guide section. A filter cylinder is provided at the bottom of the conveying section. The filter cylinder has filter holes. An air exchange valve is provided on the water-cooled tower outside the filter cylinder and the guide cylinder. The filter cylinder is connected to the water-cooled tower outside the guide cylinder and the chilled water conveying main pipe. A first drain pipe is provided on the water-cooled tower below the filter cylinder. A second drain pipe is provided at the bottom of the air-cooled tower. Both the second drain pipe and the first drain pipe are provided with drain valves.

[0011] The beneficial effects of this utility model are as follows: First, this utility model fully utilizes the heat energy carried by the circulating water returned from the bottom of the air-cooled tower as part of the heat energy for liquid oxygen vaporization. Furthermore, this product can comprehensively determine whether there is frost on the outer wall of the liquid oxygen channel of the water bath vaporizer by comprehensively judging the parameters fed back by the second and third temperature sensors. This facilitates the adjustment of the circulating water flow rate to the circulating water channel of the water bath vaporizer and the flow rate of liquid oxygen transported through the liquid oxygen delivery pipe, thereby reducing the occurrence of frost on the outer wall of the liquid oxygen channel of the water bath vaporizer.

[0012] Secondly, the circulating water conveying main pipe of this utility model is provided with a second filter, a second booster pump, a fourth temperature sensor, a third liquid flow sensor and a third regulating valve in sequence along the direction from the direction closest to the cooling tower to the direction furthest from the cooling tower; the installation of the fourth temperature sensor facilitates the feedback of temperature parameters, and the installation of the third liquid flow sensor facilitates the feedback of liquid flow parameters.

[0013] Furthermore, the liquid oxygen delivery pipe of this utility model is equipped with a liquid nitrogen pump, a second liquid flow sensor, and an eighth regulating valve. The installation of the second liquid flow sensor facilitates the feedback of liquid flow parameters.

[0014] This utility model has a simple structure, is easy to operate, and has a clever design, which greatly improves work efficiency and has good social and economic benefits. It is a product that is easy to promote and use. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model.

[0016] Figure 2 for Figure 1 A magnified view of detail A. Detailed Implementation

[0017] like Figures 1 to 2 As shown, an air separation precooling device includes an air-cooled tower 1. The air-cooled tower 1 is provided with the inlet end of a circulating water return main pipe 2, and a cooling tower 3 is provided at the outlet end of the circulating water return main pipe 2. The circulating water return main pipe 2 is provided with a first temperature sensor 4, the inlet end of a first circulating water delivery branch pipe 5, a first regulating valve 6, and the outlet end of a second circulating water delivery branch pipe 7 in sequence along the direction from the air-cooled tower 1 to the cooling tower 3. The outlet end of the first circulating water delivery branch pipe 5 is provided with the inlet end of a water bath vaporizer 8 circulating water channel. The outlet end of the water bath vaporizer 8 circulating water channel is connected to the inlet end of the second circulating water delivery branch pipe 7. The first circulating water delivery branch pipe 5 is provided with a second temperature sensor 9, an electric heater 10, a first liquid flow sensor 11, a second regulating valve 12, a first booster pump 13, and a first filter 14 in sequence along the direction from near to far from the water bath vaporizer 8. The second circulating water delivery branch pipe 7 is provided with a third temperature sensor 15 and a one-way valve 16.

[0018] The feedback value from the third temperature sensor 15 provides data for staff to determine whether there is frost or ice on the outer wall of the liquid oxygen channel of the water bath vaporizer 8. Furthermore, to facilitate the control of the liquid oxygen delivery, this product is equipped with a spare oxygen delivery pipe 17 at the outlet end of the liquid oxygen channel of the water bath vaporizer 8. An air-cooled heat exchanger 18 is installed on the spare oxygen delivery pipe 17. A liquid oxygen delivery pipe 19 is installed at the inlet end of the liquid oxygen channel of the water bath vaporizer 8. A liquid nitrogen pump 20, a second liquid flow sensor 21, and an eighth regulating valve 65 are installed on the liquid oxygen delivery pipe 19.

[0019] The air-cooled tower 1 above the circulating water return main pipe 2 is provided with the outlet end of the first air delivery pipe 22, the first packing layer 23, the cooling water nozzle 24, the second packing layer 25, the chilled water nozzle 26, the first wire mesh coalescer 27, and the second air delivery pipe 28 in sequence along the direction from near to far from the circulating water return main pipe 2. The cooling tower 3 is provided with the inlet end of the circulating water delivery main pipe 29, and the outlet end of the circulating water delivery main pipe 29 is connected to the cooling water nozzle 24. The circulating water delivery main pipe 29 is provided with the second filter 30, the second booster pump 31, the fourth temperature sensor 32, the third liquid flow sensor 33, and the third regulating valve 34 in sequence along the direction from near to far from the cooling tower 3.

[0020] The circulating water conveying main pipe 29 between the fourth temperature sensor 32 and the third liquid flow sensor 33 is provided with the inlet end of the third circulating water conveying branch pipe 35. The third circulating water conveying branch pipe 35 is provided with the fourth regulating valve 36. The outlet end of the third circulating water conveying branch pipe 35 is provided with the water cooling tower 37. The water cooling tower 37 is provided with the inlet end of the chilled water conveying main pipe 38, the outlet end of the waste nitrogen conveying pipe 39, the third packing layer 40, the circulating water nozzle 41, and the second wire mesh coalescer 42 from bottom to top. The circulating water nozzle 41 is connected to the outlet end of the third circulating water conveying branch pipe 35, and the outlet end of the chilled water conveying main pipe 38 is connected to the chilled water nozzle 26. The chilled water main pipe 38 is sequentially equipped with a fifth regulating valve 43, a fourth liquid flow sensor 44, a fifth temperature sensor 45, the inlet end of the chilled water return branch pipe 46, the chilled water channel of the chiller unit 47, a third booster pump 48, a third filter 49, and a sixth temperature sensor 50 along the direction from near the chilled water nozzle 26 to away from the chilled water nozzle 26. The chilled water main pipe 38 is connected to the water-cooled tower 37 and the outlet end of the chilled water return branch pipe 46 between the water-cooled tower 37 and the waste nitrogen gas delivery pipe 39. The chilled water return branch pipe 46 is equipped with a sixth regulating valve 51. The circulating water main pipe 29 between the third circulating water branch pipe 35 and the third liquid flow sensor 33 is equipped with the inlet end of the fourth circulating water branch pipe 52. The fourth circulating water branch pipe 52 is equipped with a seventh regulating valve 53. The outlet end of the fourth circulating water branch pipe 52 is connected to the inlet end of the cooling water channel of the chiller unit 47. The outlet end of the cooling water channel of the chiller unit 47 is connected to the circulating water return main pipe 2.

[0021] A guide cylinder 54 is installed inside the water-cooled tower 37 below the nitrogen gas conveying pipe 39. The outlet end of the chilled water return branch pipe 46 is connected to the water-cooled tower 37 above the guide cylinder 54. The guide cylinder 54 includes a guide section and a conveying section provided at the bottom end of the guide section. The top of the guide section is connected to the inner wall of the water-cooled tower 37. The guide section adopts an inverted frustum-shaped tubular structure. The diameter of the inner circle of the guide section gradually decreases as the height of the guide section decreases. The conveying section adopts a circular tubular structure, and the inner cavity of the conveying section is straight. The diameter corresponds to the minimum diameter of the inner cavity of the guide section. A filter cylinder 55 is provided on the bottom of the conveying section. A filter hole 56 is provided on the filter cylinder 55. An air exchange valve 57 is provided on the water cooling tower 37 outside the filter cylinder 55 and the guide cylinder 54. The filter cylinder 55 is connected to the water cooling tower 37 outside the guide cylinder 54 and the chilled water conveying main pipe 38. A first drain pipe 58 is provided on the water cooling tower 37 below the filter cylinder 55. A second drain pipe 59 is provided at the bottom of the air cooling tower 1. A drain valve 60 is provided on both the second drain pipe 59 and the first drain pipe 58. This facilitates the guidance of the guide cylinder 54 to direct the water supplied to the water-cooling tower 37 into the inner cavity of the guide cylinder 54 and then into the inner cavity of the filter cylinder 55. After filtration through the filter holes 56 on the filter cylinder 55, the mechanical impurities carried by the circulating water supplied to the chilled water supply main pipe 38 are reduced. The mechanical impurities are temporarily stored inside the filter cylinder 55 after filtration through the filter holes 56, making it easy to discharge them using the first drain pipe 58. During the filtration process, the waste nitrogen gas supplied by the waste nitrogen gas supply pipe 39 carries its own pressure. After opening the ventilation valve 57, the pressure carried by the waste nitrogen gas can overcome the flow resistance provided by the filter holes 56 on the filter cylinder 55 for filtration. A first liquid level sensor 61 is installed on the water-cooling tower 37 above the guide cylinder 54 and on the guide cylinder 54. A second liquid level sensor 62 is installed on the water-cooling tower 37 outside the guide cylinder 54, and a third liquid level sensor 63 is installed at the bottom of the air-cooled tower 1. The installation of the first liquid level sensor 61, the second liquid level sensor 62, and the third liquid level sensor 63 is all for the purpose of facilitating the feedback of liquid level parameters. A self-cleaning air filter 64 is installed at the inlet end of the first air delivery pipe 22, and an air compressor unit 65 is installed on the first air delivery pipe 22.

[0022] The usage instructions for this product are as follows: Figures 1 to 2 As shown, it includes the following steps: S1. Outside air is filtered by a self-cleaning air filter 64 and then compressed by an air compressor unit 65 to form compressed air. The compressed air is delivered to the air-cooled tower 1 through the outlet of the first air delivery pipe 22, forming an upward airflow that rises along the inner cavity of the air-cooled tower 1. During its upward movement within the air-cooled tower 1, the upward airflow first exchanges heat with the cooling water delivered by the cooling water nozzle 24 in a counter-current manner. Then, the upward airflow exchanges heat with the chilled water delivered by the chilled water nozzle 26 in a counter-current manner. After that, the upward airflow continues to rise, undergoes gas-liquid separation by the first wire mesh coalescer 27, and is then delivered to the downstream process through the second air delivery pipe 28. The chilled water delivered by the chilled water nozzle 26 enters the air-cooled tower 1, forming a first downward liquid flow that descends along the air-cooled tower 1. Then, it merges with the cooling water delivered by the cooling water nozzle 24 to form a second downward liquid flow that continues to descend along the air-cooled tower 1, ultimately forming a circulating water enrichment layer at the bottom of the air-cooled tower 1.

[0023] S2. The circulating water enrichment layer continuously supplies circulating water to the circulating water return main pipe 2. After the temperature is fed back by the first temperature sensor 4, it is divided into two parts, namely the first part of circulating water return and the second part of circulating water return. The first part of circulating water return continues to move forward along the circulating water return main pipe 2, while the second part of circulating water return is supplied to the first circulating water delivery branch pipe 5. After being pressurized by the first booster pump 13, it is supplied to the electric heater 10 for heating. After the temperature is fed back by the second temperature sensor 9, it is continuously supplied to the circulating water channel of the water bath vaporizer 8. After heat exchange with the medium supplied to the liquid oxygen channel of the water bath vaporizer 8, it is sent back to the circulating water return main pipe 2 through the second circulating water delivery branch pipe 7. It merges with the first part of circulating water return to form the third circulating water return and is supplied to the cooling tower 3 for cooling.

[0024] Meanwhile, the liquid oxygen delivery pipe 19 receives liquid oxygen from the liquid oxygen storage tank. After entering the liquid oxygen delivery pipe 19, the liquid oxygen is pressurized by the liquid nitrogen pump 20 and then delivered to the liquid oxygen channel of the water bath vaporizer 8 for heat exchange with the medium continuously supplied to the circulating water channel of the water bath vaporizer 8. The liquid oxygen vaporizes in the liquid oxygen channel of the water bath vaporizer 8 to form oxygen and is delivered to the standby oxygen delivery pipe 17. During this period, it is delivered to the oxygen supply network through the cold source channel of the air-cooled heat exchanger 18 and the air adjacent to the air-cooled heat exchanger 18.

[0025] It should be noted that the flow rate of the second part of the circulating water transported through the first circulating water transport branch pipe 5 and the flow rate of liquid oxygen transported through the liquid oxygen transport pipe 19 should be adjusted in a timely manner based on the temperature feedback from the third temperature sensor 15 and the temperature feedback from the second temperature sensor 9, so as to reduce the occurrence of frost or even ice formation on the outer wall of the liquid oxygen channel of the water bath vaporizer 8.

[0026] S3. The third circulating water return is sent back to the cooling tower 3 and cooled by the cooling tower 3 to form cooling water. The cooling water is transported to the circulating water transport main pipe 29 and divided into three parts: the first part of circulating water, the second part of circulating water, and the third part of circulating water. The first part of circulating water is continuously transported to the cooling water nozzles 24 as cooling water for the air-cooled tower 1. The second part of circulating water is transported to the inlet end of the cooling water channel of the chiller unit 47, and then from the outlet end of the cooling water channel of the chiller unit 47 to the circulating water return main pipe 2. The third portion of circulating water is sequentially transported to the water-cooling tower 37 via the third circulating water delivery branch pipe 35 and the circulating water nozzle 41. When the third portion of circulating water enters the water-cooling tower 37, it forms a third descending liquid flow. The third descending liquid flow descends along the inner cavity of the water-cooling tower 37 and exchanges heat with the polluted nitrogen gas transported via the polluted nitrogen gas delivery pipe 39 in a countercurrent manner. After the third descending liquid flow and the polluted nitrogen gas exchange heat in a countercurrent manner, they are cooled and then continue to descend along the water-cooling tower 37 into the inner cavity of the guide cylinder 54. After being filtered by the filter holes 56 on the filter cylinder 55, it enters the water-cooling tower 37 outside the filter cylinder 55 and the guide cylinder 54 to form low-temperature water.

[0027] S4. The low-temperature water enters the chilled water delivery main pipe 38, is pressurized by the third booster pump 48, and then delivered to the chilled water channel of the chiller unit 47 for further cooling to form chilled water. The chilled water is divided into two parts: a first part and a second part. The first part of the chilled water is delivered to the chilled water nozzle 26 for use as chilled water in the air-cooled tower 1. The second part of the chilled water is returned to the water-cooled tower 37 via the chilled water return branch pipe 46 and merges with the third descending liquid flow delivered to the guide cylinder 54, thereby reducing the temperature of the third descending liquid flow and thus reducing the temperature of the low-temperature water, which is then used as a cold source to adjust the temperature of the first part of the chilled water.

[0028] In this embodiment, the heat energy carried by the circulating water returned from the bottom of the air-cooled tower 1 is fully utilized as part of the heat energy for liquid oxygen vaporization. Furthermore, this product can comprehensively determine whether there is frost on the outer wall of the liquid oxygen channel of the water bath vaporizer 8 by using parameters fed back by the second temperature sensor 9 and the third temperature sensor 15. This facilitates the adjustment of the circulating water flow rate to the circulating water channel of the water bath vaporizer 8 and the flow rate of liquid oxygen delivered through the liquid oxygen delivery pipe 19, thereby reducing the occurrence of frost on the outer wall of the liquid oxygen channel of the water bath vaporizer 8.

[0029] The embodiments described above are merely preferred embodiments of this utility model and are not intended to limit the scope of implementation of this utility model. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the patent claims of this utility model should be included within the scope of the patent application of this utility model.

Claims

1. An air separation precooling device, comprising an air-cooled tower (1), wherein the air-cooled tower (1) is provided with an inlet end of a circulating water return main pipe (2), characterized in that: A cooling tower (3) is installed at the outlet end of the circulating water return main pipe (2). Along the direction from the air-cooled tower (1) to the cooling tower (3), the first temperature sensor (4), the inlet end of the first circulating water delivery branch pipe (5), the first regulating valve (6), and the outlet end of the second circulating water delivery branch pipe (7) are sequentially installed on the circulating water return main pipe (2). The inlet end of the circulating water channel of the water bath vaporizer (8) is installed at the outlet end of the first circulating water delivery branch pipe (5). The outlet end is connected to the inlet end of the second circulating water conveying branch pipe (7). The first circulating water conveying branch pipe (5) is provided with a second temperature sensor (9), an electric heater (10), a first liquid flow sensor (11), a second regulating valve (12), a first booster pump (13) and a first filter (14) in sequence along the direction from near the water bath vaporizer (8) to away from the water bath vaporizer (8). The second circulating water conveying branch pipe (7) is provided with a third temperature sensor (15) and a one-way valve (16).

2. The air separation precooling equipment according to claim 1, characterized in that: The water bath vaporizer (8) is provided with a spare oxygen delivery pipe (17) at the outlet end of the liquid oxygen channel, and an air-cooled heat exchanger (18) is provided on the spare oxygen delivery pipe (17). The water bath vaporizer (8) is provided with a liquid oxygen delivery pipe (19) at the inlet end of the liquid oxygen channel, and a liquid nitrogen pump (20), a second liquid flow sensor (21) and an eighth regulating valve (65) are provided on the liquid oxygen delivery pipe (19).

3. The air separation precooling equipment according to claim 1, characterized in that: The air-cooled tower (1) above the circulating water return main pipe (2) is provided with the outlet end of the first air delivery pipe (22), the first packing layer (23), the cooling water nozzle (24), the second packing layer (25), the chilled water nozzle (26), the first wire mesh coalescer (27), and the second air delivery pipe (28) in sequence along the direction from near the circulating water return main pipe (2) to away from the circulating water return main pipe (2). The cooling tower (3) is provided with the inlet end of the circulating water delivery main pipe (29). The outlet end of the circulating water delivery main pipe (29) is connected to the cooling water nozzle (24). The circulating water delivery main pipe (29) is provided with the second filter (30), the second booster pump (31), the fourth temperature sensor (32), the third liquid flow sensor (33), and the third regulating valve (34) in sequence along the direction from near the cooling tower (3) to away from the cooling tower (3).

4. The air separation precooling equipment according to claim 3, characterized in that: The inlet end of the third circulating water conveying branch pipe (35) is provided on the circulating water conveying main pipe (29) between the fourth temperature sensor (32) and the third liquid flow sensor (33). The third circulating water conveying branch pipe (35) is provided with a fourth regulating valve (36). The outlet end of the third circulating water conveying branch pipe (35) is provided with a water cooling tower (37). The water cooling tower (37) is provided with the inlet end of the chilled water conveying main pipe (38), the outlet end of the waste nitrogen conveying pipe (39), the third packing layer (40), the circulating water nozzle (41), and the second wire mesh coalescer (42) arranged sequentially from bottom to top. The circulating water nozzle (41) and the outlet end of the third circulating water conveying branch pipe (35) are connected. The outlet end of the chilled water conveying main pipe (38) and the chilled water nozzle (26) are connected.

5. The air separation precooling equipment according to claim 4, characterized in that: The chilled water main pipe (38) is provided with a fifth regulating valve (43), a fourth liquid flow sensor (44), a fifth temperature sensor (45), the inlet end of the chilled water return branch pipe (46), the chilled water channel of the chiller unit (47), a third booster pump (48), a third filter (49) and a sixth temperature sensor (50) in sequence along the direction from near the chilled water nozzle (26) to away from the chilled water nozzle (26). The water cooling tower (37) between the chilled water main pipe (38) and the waste nitrogen gas transmission pipe (39) and the outlet end of the chilled water return branch pipe (46) are connected. The chilled water return branch pipe (46) is provided with a sixth regulating valve (51).

6. The air separation precooling equipment according to claim 4, characterized in that: A guide cylinder (54) is installed inside the water-cooled tower (37) below the nitrogen gas conveying pipe (39). The guide cylinder (54) includes a guide section and a conveying section provided at the bottom end of the guide section. The top of the guide section is connected to the inner wall of the water-cooled tower (37). The guide section adopts an inverted frustum-shaped tubular structure. The diameter of the inner circle of the guide section gradually decreases as the height of the guide section decreases. The conveying section adopts a circular tubular structure. The inner diameter of the conveying section corresponds to the minimum diameter of the inner cavity of the guide section. A guide cylinder (54) is provided at the bottom of the conveying section. A filter cartridge (55) is provided, and a filter hole (56) is provided on the filter cartridge (55). An air exchange valve (57) is provided on the water cooling tower (37) outside the filter cartridge (55) and the guide cylinder (54). The filter cartridge (55) is connected to the water cooling tower (37) outside the guide cylinder (54) and the chilled water conveying main pipe (38). A first drain pipe (58) is provided on the water cooling tower (37) below the filter cartridge (55). A second drain pipe (59) is provided at the bottom of the air cooling tower (1). A drain valve (60) is provided on both the second drain pipe (59) and the first drain pipe (58).

Images