Online back flushing method for tubular water distributor of air cooling tower

Abstract

The invention discloses an online back flushing method for a tubular water distributor of an air cooling tower, and relates to the technical field of online back flushing of water distributors. Comprising the following steps: S1, stopping the water chilling unit; s2, a backflow pipeline is opened, a chilled water backflow valve is firstly opened after the water chilling unit stops running, then a chilled water feeding isolation valve is closed, and chilled water pumped in from a chilled water pump can flow back into the water cooling tower from the backflow pipeline at the moment; s3, a chilled water feeding valve is closed, then a chilled water pipe blow-off valve is opened, and then the chilled water feeding valve is intermittently and repeatedly closed and opened; through remote control of a valve in the device, on-line blowback dirt removal of a chilled water path and a cooling water path is realized under the condition that a chilled water pump is not stopped, the temperature difference between air at an outlet of an air cooling tower and chilled water can be reduced, and the operation energy consumption of the device is reduced; and remote blowback can be carried out without manual field valve operation, so that quickness and manpower and time saving are realized.

Description

Technical Field

[0001] The invention relates to the technical field of online backflushing of a water distributor, and in particular to an online backflushing method for an air-cooled tower tube type water distributor. Background Art

[0002] With the continuous development of economy and technology, the scale of single air separation equipment is getting larger and larger. In large coal chemical and steel enterprises, it undertakes the gas supply task of the entire enterprise. Once a failure occurs, it will have a great impact on the safety and stable operation of subsequent production equipment. The operation cycle of the air separation unit refers to the time of continuous normal operation of the oxygen generator, and its length is one of the important indicators to measure the operating status and economic performance of the unit. In the operation of the air separation unit, it is inevitable that the operating conditions will be unstable. How to eliminate or alleviate the problem online and reduce the number of shutdowns. Therefore, the process and method of solving the problem online without stopping the machine are more important for the long-term stable operation and economy of the device. The nitrogen water precooling system of the air separation unit is an important part of the air separation unit. Its main function is to cool and purify the raw air. The air cooling tower is the key equipment of the nitrogen water precooling system. The cooling and purification of the air are completed in the air cooling tower. The high-temperature air from the air compressor enters the bottom of the air cooling tower, and contacts and exchanges heat with the cooling water in the middle of the air cooling tower and the chilled water distributor at the top after spraying. Finally, the compressed air at about 80°C is cooled to about 10°C to meet the working temperature requirements of the molecular sieve. Due to the particularity of equipment and process, the circulating water in the nitrogen water precooling system often produces scaling and corrosion during the cooling and heat exchange process. Once the distribution holes of the cooling water and chilled water distributors are blocked by scaling, debris, etc., affecting the chilled water flow, the outlet temperature of the air-cooling tower will increase and the energy consumption of the device will increase. The conventional means to solve the above problems is to perform manual cleaning and dredging, which is time-consuming, labor-intensive, and requires the device to be shut down, resulting in huge costs.

[0003] After searching, the Chinese patent publication number CN112944806A discloses an air separation precooling system, including an air cooling tower and a water cooling tower, the top of the air cooling tower is provided with an air outlet, the bottom of the air cooling tower is provided with an air cooling tower mist collector, the bottom of the air cooling tower is provided with a sewage outlet, the upper water distributor and the lower water distributor are provided inside, and the upper cooling water pipeline and the normal temperature circulating water pipeline connected to the upper part of the two water distributors by pipelines are provided on one side of the upper water distributor and the lower water distributor. The above patent lacks the function of automatically cleaning the cooling water and chilled water distributors and pipelines online, and the cleaning needs to be stopped, which is time-consuming and labor-intensive, and requires the shutdown of the device at a huge cost. Summary of the invention

[0004] The purpose of the present invention is to solve the shortcomings of the prior art and to propose an online backflushing method for an air-cooled tower tube water distributor.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An online backflushing method for an air-cooling tower tubular water distributor comprises the following steps:

[0007] S1: Shut down the chiller;

[0008] S2: Open the return pipeline. After the chiller is shut down, open the chilled water return valve first, and then close the chilled water supply isolation valve. At this time, the chilled water pumped in from the chilled water pump will flow back into the water cooling tower through the return pipeline.

[0009] S3: Close the chilled water inlet valve and then open the chilled water pipe blow-off valve. Then, the chilled water inlet valve is repeatedly closed and opened intermittently to allow the compressed air inside the air-cooling tower to pass through the chilled water distributor to form air turbulence, and allow the rapidly flowing air to enter the pipeline from the spray hole on the lower side of the chilled water distributor. At this time, the rapidly flowing air blows away the impurities at the spray hole of the chilled water distributor, and together with the gas, passes through the chilled water inlet valve and the chilled water backflush pipe and is ejected from the chilled water pipe blow-off valve.

[0010] S4: Stop the cooling water pump;

[0011] S5: Close the cooling water supply isolation valve, then close the cooling water supply valve, and then open the cooling water pipe blow-off valve. At this time, control the cooling water supply valve to be intermittently closed and opened repeatedly to allow the compressed gas inside the air-cooling tower to enter the cooling water distributor. These gases form air turbulence at the cooling water distributor, and then the compressed gas enters through the spray holes of the cooling water distributor. The fast-flowing air will carry away impurities, and then these gases pass through the cooling water supply valve and the cooling water backflush pipe and are ejected from the cooling water pipe blow-off valve.

[0012] Furthermore: the back-flushing in step S1 and step S2 is performed at the end of the molecular sieve cold blowing.

[0013] Furthermore: during the backflushing cleaning, the chiller, the chilled water supply valve, the chilled water pipe blow-off valve, the chilled water reflux valve, the chilled water supply isolation valve, the cooling water pump, the cooling water supply valve, the cooling water pipe blow-off valve and the cooling water supply isolation valve can all be switched on and off by remote control.

[0014] As a preferred solution of the present invention: the chilled water supply isolation valve and the cooling water supply isolation valve can adjust the backwash cleaning intensity by switching themselves.

[0015] The beneficial effects of the present invention are:

[0016] 1. An online backflushing method for an air-cooling tower tubular water distributor realizes the function of online backflushing to remove dirt in the chilled water circuit and the cooling water circuit without stopping the chilled water pump through remote control of the valves in the device, which can reduce the temperature difference between the air and the chilled water at the outlet of the air-cooling tower and reduce the energy consumption of the device operation; and the backflushing can be performed remotely without the need for manual on-site valve operation, which is faster and saves manpower and time.

[0017] 2. An online backflushing method for an air-cooling tower tubular water distributor, which can guide the water flow back to the water-cooling tower through a reflux pipe when the chilled water upper water isolation valve is closed for backflushing to prevent waste and damage to the pipeline.

[0018] 3. An online backflushing method for an air-cooled tower tube water distributor, which performs backflushing cleaning at the end of the molecular sieve cold blowing to protect the working adsorption elasticity of the molecular sieve and better control the backflushing cleaning time. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a schematic diagram of the mechanism structure of an online back-flushing method for an air-cooled tower tube water distributor.

[0020] In the figure: 1. Air cooling tower; 2. Water cooling tower; 3. Cooling water pump; 4. Chilled water pump; 5. Chiller; 6. Chilled water distributor; 7. Cooling water distributor; 8. Chilled water supply valve; 9. Chilled water pipe blow-off valve; 10. Cooling water supply valve; 11. Cooling water pipe blow-off valve; 12. Chilled water return valve; 13. Chilled water supply isolation valve; 14. Cooling water supply isolation valve; 15. Compressed air outlet; 16. Compressed air inlet; 17. Nitrogen and polluted nitrogen outlet; 18. Water cooling tower water supply pipe; 19. Nitrogen and polluted nitrogen inlet; 20. Circulating water supply port; 21. Circulating water outlet; 22. Chilled water backflush pipe; 23. Cooling water backflush pipe; 24. Reflux pipe. DETAILED DESCRIPTION

[0021] The technical solution of this patent is further described in detail below in conjunction with specific implementation methods.

[0022] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0023] Embodiment 1:

[0024] An online backflush method for an air-cooled tower tube water distributor, such as Figure 1 As shown, the following steps are included:

[0025] S1: Shut down the chiller 5. Considering the adsorption elasticity of the molecular sieve, the last stage of the molecular sieve cold blowing can better control the backwashing time, because water distribution is not required during the backwashing cleaning. Therefore, the chiller 5 can be stopped, which can save electricity and reduce energy consumption during the backwashing cleaning period.

[0026] S2: Open the return pipe 24. After the chiller 5 stops operating, first open the chilled water return valve 12, and then close the chilled water supply isolation valve 13. At this time, the chilled water pumped from the chilled water pump 4 will flow back into the water cooling tower 2 from the return pipe 24. Opening the chilled water return valve 12 first and then closing the chilled water supply isolation valve 13 can prevent the water pressure from rising and damaging the pipe;

[0027] S3: Close the chilled water inlet valve 8 and then open the chilled water pipe blow-off valve 9, and then intermittently and repeatedly close and open the chilled water inlet valve 8, so that the compressed air inside the air-cooling tower 1 forms air turbulence through the chilled water distributor 6, and the rapidly flowing air enters the pipeline from the spray hole on the lower side of the chilled water distributor 6. At this time, the rapidly flowing air blows away the impurities at the spray hole of the chilled water distributor 6, and together with the gas, passes through the chilled water inlet valve 8 and the chilled water backflush pipe 22 and is ejected from the chilled water pipe blow-off valve 9. The chilled water inlet isolation valve 13 can adjust the backflush amplitude through the switch to achieve the purpose of online cleaning of the chilled water distributor 6. When backflush cleaning of the chilled water distributor 6 is performed, the chiller 5, the chilled water inlet valve 8, the chilled water pipe blow-off valve 9, the chilled water reflux valve 12 and the chilled water inlet isolation valve 13 can be remotely controlled, without the need for manual offline operation, and remote operation and remote processing can be achieved, which saves more time.

[0028] S4: Stop the cooling water pump 3, clean the cooling water distributor 7 after the chilled water distributor 6 is cleaned. The cleaning of the chilled water distributor 6 and the cleaning of the cooling water distributor 7 should not be performed continuously to prevent the operation time from affecting the adsorption of the molecular sieve; it is selected to be performed at the end of the cold blowing of different molecular sieves to better control the backblowing cleaning time;

[0029] S5: Close the cooling water supply isolation valve 14, then close the cooling water supply valve 10, and then open the cooling water pipe blow-off valve 11. At this time, the cooling water supply valve 10 is controlled to be intermittently closed and opened repeatedly to allow the compressed gas inside the air-cooling tower 1 to enter the cooling water distributor 7. These gases form air turbulence at the cooling water distributor 7, and then the compressed gas enters through the spray hole of the cooling water distributor 7. The fast-flowing air will take away impurities. Then these gases pass through the cooling water supply valve 10 and the cooling water backflush pipe 23 and are ejected from the cooling water pipe blow-off valve 11 to achieve the purpose of online cleaning without stopping the machine; the cooling water supply isolation valve 14 can adjust the backflush amplitude through the switch, and at the same time, the cooling water pump 3, the cooling water supply valve 10, the cooling water pipe blow-off valve 11 and the cooling water supply isolation valve 14 can also be remotely controlled, without the need for manual offline operation, which is faster and saves time.

[0030] When the present embodiment is in use, a chilled water supply isolation valve 13, a chilled water pipe blow-off valve 9, a cooling water supply isolation valve 14 and a cooling water pipe blow-off valve 11 are installed on one end of the chilled water distributor 6 and the cooling water distributor 7 on one side of the air-cooling tower 1. By remotely controlling the valves in the device, the function of online back-blowing to remove dirt from the chilled water circuit and the cooling water circuit can be achieved without stopping the chilled water pump, thereby reducing the temperature difference between the air and the chilled water at the outlet of the air-cooling tower 1 and reducing the energy consumption of the device. Back-blowing can also be performed remotely without the need for manual on-site valve operation, which is faster and saves manpower and time.

[0031] The above is a preferred specific implementation manner of the present invention, and the protection scope of the present invention is not limited thereto. Any modification, equivalent substitution and improvement made by any technician familiar with the field within the technical scope disclosed by the present invention in combination with the prior art or public common sense, within the spirit and principle of the present invention, shall be covered by the protection scope of the present invention.

Claims

1. An online backflushing method for an air-cooled tower tubular water distributor, characterized in that: The steps include: S1: Shut down the chiller (5); S2: Open the return pipe (24). After the chiller (5) stops operating, first open the chilled water return valve (12), and then close the chilled water supply isolation valve (13). At this time, the chilled water pumped in from the chilled water pump (4) will flow back into the water cooling tower (2) through the return pipe (24); S3: close the chilled water inlet valve (8) and then open the chilled water pipe blow-off valve (9), and then intermittently and repeatedly close and open the chilled water inlet valve (8) to allow the compressed air inside the air cooling tower (1) to pass through the chilled water distributor (6) to form air turbulence, and allow the rapidly flowing air to enter the pipeline from the spray hole on the lower side of the chilled water distributor (6). At this time, the rapidly flowing air blows away the impurities at the spray hole of the chilled water distributor (6), and together with the gas, passes through the chilled water inlet valve (8) and the chilled water backflush pipe (22) to be ejected from the chilled water pipe blow-off valve (9); S4: Stop the cooling water pump (3); S5: Close the cooling water supply isolation valve (14), then close the cooling water supply valve (10), and then open the cooling water pipe blow-off valve (11). At this time, the cooling water supply valve (10) is controlled to be intermittently closed and opened repeatedly to allow the compressed gas inside the air-cooling tower (1) to enter the cooling water distributor (7). These gases form air turbulence at the cooling water distributor (7), and then the compressed gas enters through the spray hole of the cooling water distributor (7). The fast-flowing air will carry away impurities, and then these gases pass through the cooling water supply valve (10) and the cooling water backflush pipe (23) and are ejected from the cooling water pipe blow-off valve (11).

2. The online backflushing method of an air-cooling tower tubular water distributor according to claim 1 is characterized in that: The back-flushing time in step S1 and step S2 is both at the end of the molecular sieve cold blowing.

3. The online backflushing method of an air-cooling tower tubular water distributor according to claim 2 is characterized in that: During the back-flushing cleaning, the chiller (5), the chilled water supply valve (8), the chilled water pipe blow-off valve (9), the chilled water return valve (12), the chilled water supply isolation valve (13), the cooling water pump (3), the cooling water supply valve (10), the cooling water pipe blow-off valve (11) and the cooling water supply isolation valve (14) can all be switched on and off by remote control.

4. The online backflushing method of an air-cooling tower tubular water distributor according to claim 3 is characterized in that: The chilled water upper water isolation valve (13) and the cooling water upper water isolation valve (14) can adjust the backwash cleaning intensity by switching themselves.

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