Chemical cooling circulating water turbidity control system and application method thereof

Abstract

The invention relates to the technical field of chemical production, particularly discloses a chemical cooling circulating water turbidity control system and an application method thereof, and solves the problems that in the process of cooling chemical equipment by circulating water for a long time at present, as the circulating water is easily polluted by a chemical cleaning agent or the environment, the turbidity is continuously increased, and the cooling effect is poor. And finally, the cooling effect of the chemical equipment is influenced. According to the system, a plurality of cut-off control valves are arranged at water inlet and outlet pipelines of a filter, a liquid level meter is additionally arranged at the top of a slurry tank, and a plurality of control valves are arranged between the slurry tank and a press filter, so that circulating water is further filtered through the additional filter when being subjected to conventional cooling heat exchange circulation; the cleanliness of the cooling water entering the circulating water tank is further improved; and the slag slurry water backwashed by the filter is further filtered by the press filter, so that the filtered slag slurry water is pumped into the circulating water tank again, the turbidity of the cooling circulating water is effectively reduced, and the recycling rate of the filtered slag slurry water is improved.

Description

Technical Field

[0001] The invention relates to the technical field of chemical production, and specifically discloses a chemical cooling circulating water turbidity control system and an application method thereof. Background Art

[0002] At present, in the chemical production process, circulating water is used as the cooling medium for most chemical plants. It is mainly used for cooling production equipment and facilities. The heat is removed through the circulating cooling water system to maintain the stable operation of the production equipment within an appropriate temperature range. Circulating water is used as a cooling medium. After absorbing the heat generated by the equipment in the heat exchanger, the heat is dissipated into the environment through the cooling tower or other cooling facilities, and then circulated back to the equipment for cooling. If the turbid circulating water that is used for a long time is not properly treated, it will bring a series of problems, such as microbial growth, severe scaling and increased corrosion, all of which will have a negative impact on equipment efficiency and production processes. After the water supply indicators are maintained by adding chemical agents such as flocculation, sterilization, corrosion inhibition and scale inhibitors, it is very easy for microorganisms to overgrow due to improper addition of agents, so that scaling substances in the system pipes are dissolved in the circulating water, resulting in an increase in the turbidity index of the circulating water. In addition, since the circulating water system is an open system, when encountering severe weather such as strong winds, dust will carry a large amount of impurities into the circulating water, resulting in an increase in the turbidity index of the circulating water. When the operating indicators are reduced by system drainage replacement, on the one hand, due to the large design circulation volume of the circulating water system, the drainage replacement requires a large discharge volume, resulting in a waste of water resources and an increase in production and operation costs. On the other hand, the large discharge of circulating water will increase the operating load of the subsequent sewage treatment equipment, and the sewage discharge indicators are difficult to guarantee, which is contrary to the national policy of zero wastewater discharge and difficult to achieve environmentally friendly production of the equipment. Summary of the invention

[0003] The present invention provides a chemical cooling circulating water turbidity control system and an application method thereof, in order to solve the problem that during the long-term cooling process of chemical equipment by circulating water, the turbidity of the circulating water is continuously increased due to the circulating water being easily polluted by chemical detergents or the environment, thus ultimately affecting the cooling effect of the chemical equipment.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: A chemical cooling circulating water turbidity control system comprises a circulating water pool, a circulating water pump and a cooler, wherein the circulating water pool, the circulating water pump and the cooler are connected to form a circulating water circuit, a filter is connected to the pipeline between the water inlet of the circulating water pool and the cooler, the water outlet of the filter is connected to the circulating water pool, the water inlet of the filter is also connected to a slurry pool, the slurry pool is connected to a filter press, and the water outlet of the filter press is connected to the circulating water pool.

[0005] Furthermore, a first shut-off valve is provided on the pipe between the water inlet of the filter and the slurry pool, a second shut-off valve is provided on the pipe between the water inlet of the filter and the cooler, a third shut-off valve is provided on the pipe between the water outlet of the filter and the circulating water pool, a fourth shut-off valve is provided on the pipe between the water inlet of the second shut-off valve and the water outlet of the filter, a second pressure gauge is provided at the water inlet of the filter, a third pressure gauge is provided at the water outlet of the filter, and the first shut-off valve, the second shut-off valve, the third shut-off valve, the fourth shut-off valve, the second pressure gauge and the third pressure gauge are all connected to the PLC controller.

[0006] Furthermore, a liquid level gauge is provided in the slurry pool, a third valve, a slurry pump and a fourth valve are provided in sequence on the pipeline between the outlet of the slurry pool and the filter press, a sixth valve is provided at the water outlet of the filter press, and the liquid level gauge, slurry pump, third valve, fourth valve and sixth valve are all connected to the PLC controller.

[0007] Furthermore, a connecting pipe is provided between the water outlet of the slurry pump and the circulating water tank, a fifth valve is provided on the connecting pipe, and the fifth valve is connected to the PLC controller.

[0008] An application method of a chemical cooling circulating water turbidity control system comprises the following steps: Step 1. A part of the circulating water drawn out from the cooler continues to circulate and cool through the circulating water pool, and the other part of the circulating water enters the filter for filtration after the PLC controller controls the second and third shut-off valves to open and the first and fourth shut-off valves to close, so that the circulating water enters the circulating water pool for stable heat exchange and cooling after being filtered through the filter.

[0009] Step 2. When the pressure difference between the second pressure gauge and the third pressure gauge of the filter is greater than the set value, the PLC controller controls the first shut-off valve and the fourth shut-off valve to open, and closes the second shut-off valve and the third shut-off valve at the same time. The circulating water flows upward from the bottom of the filter. After the filter is backwashed for the set time, the slurry water after backwashing enters the slurry pool. Then the PLC controller controls the third valve, the fourth valve and the sixth valve to open, and closes the fifth valve. When the liquid level gauge detects that the slurry water level in the slurry pool is not lower than 70% of the slurry pool capacity, the PLC controller controls the slurry pump to open and transport the slurry water to the filter press for filtration. When the liquid level gauge detects that the slurry water level in the slurry pool is not higher than 30% of the slurry pool capacity, the PLC controller controls the slurry pump to close and stop transporting the slurry water. The slurry circulating water filtered by the filter press flows back to the circulating water pool. Then the PLC controller controls the first shut-off valve and the fourth shut-off valve to close, and opens the second shut-off valve) and the third shut-off valve at the same time, so that the filter can filter the cooling circulating water normally.

[0010] Step 3: After the filter has completed the set operation cycle, the PLC controller controls the fourth valve and the sixth valve to close, and the filter press collects the filtered sludge. At the same time, the fifth valve is opened, and the slurry pump continues to pump the slurry water in the slurry pool to the circulating water pool for recycling.

[0011] The present invention has the following beneficial effects: The present invention adds filters, slurry pools, slurry pumps, filter presses and other equipment to the existing cooling circulating water loop, so that the PLC controller controls the opening of the second shut-off valve and the third shut-off valve, and closes the first shut-off valve and the fourth shut-off valve at the same time, thereby ensuring that the circulating water enters the circulating water pool for stable heat exchange cooling after being filtered by the filter, thereby effectively reducing the turbidity of the heat exchange cooling circulating water and improving the cooling effect of the chemical equipment.

[0012] In the present invention, when the pressure difference between the second pressure gauge and the third pressure gauge of the filter reaches a preset value, the PLC controller controls the first shut-off valve and the fourth shut-off valve to open, and closes the second shut-off valve and the third shut-off valve at the same time, so that the circulating water flows upward from the bottom of the filter to achieve backwashing of the filter. The slurry water after backwashing enters the slurry pool. When the liquid level meter detects that the slurry water level in the slurry pool is not lower than 70% of the slurry pool capacity, the slurry pump is turned on and the slurry water is transported to the filter press for filtration. The clean slurry water after filtration is pumped back into the circulating water pool, thereby improving the cleanliness of the circulating water and its overall recycling rate.

[0013] In the present invention, the fourth valve and the sixth valve are controlled to be closed, and the filtered sludge is collected by the sludge collecting tank. At the same time, the fifth valve is opened, and the slurry pump continues to pump the slurry water in the slurry pool into the circulating water pool, effectively avoiding the overflow and external discharge waste of the circulating slurry water in the slurry pool when the filter press leaks sludge or a filter press failure occurs. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the overall structure of the system of the present invention.

[0015] The meanings of the reference numerals are as follows: 1. Circulating water pool; 2. Circulating water pump; 3. Cooler; 4. Filter; 5. Slurry pool; 6. Slurry pump; 7. Filter press; 8. Mud collecting tank; 9. PLC controller; 10. Electric valve; 11. First valve; 12. Second valve; 13. First shut-off valve; 14. Second shut-off valve; 15. Third shut-off valve; 16. Fourth shut-off valve; 17. Third valve; 18. Fourth valve; 19. Fifth valve; 20. Sixth valve; 21. Liquid level meter; 22. First pressure gauge; 23. Second pressure gauge; 24. Third pressure gauge. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0017] like Figure 1 As shown, a chemical cooling circulating water turbidity control system comprises a circulating water pool 1, a circulating water pump 2 and a cooler 3, wherein the circulating water pool 1, the circulating water pump 2 and the cooler 3 are connected to form a circulating water circuit, a filter 4 is connected to the pipeline between the water inlet of the circulating water pool 1 and the cooler 3, the water outlet of the filter 4 is connected to the circulating water pool 1, the water inlet of the filter 4 is also connected to a slurry pool 5, the slurry pool 5 is connected to a filter press 7, and the water outlet of the filter press 7 is connected to the circulating water pool 1.

[0018] A first shut-off valve 13 is provided on the pipeline between the water inlet of the filter 4 and the slurry pool 5, a second shut-off valve 14 is provided on the pipeline between the water inlet of the filter 4 and the cooler 3, a third shut-off valve 15 is provided on the pipeline between the water outlet of the filter 4 and the circulating water pool 1, a fourth shut-off valve 16 is provided on the pipeline between the water inlet of the second shut-off valve 14 and the water outlet of the filter 4, a second pressure gauge 23 is provided at the water inlet of the filter 4, a third pressure gauge 24 is provided at the water outlet of the filter 4, and the first shut-off valve 13, the second shut-off valve 14, the third shut-off valve 15, the fourth shut-off valve 16, the second pressure gauge 23 and the third pressure gauge 24 are all connected to the PLC controller 9.

[0019] A liquid level gauge 21 is provided in the slurry pool 5, and a third valve 17, a slurry pump 6 and a fourth valve 18 are provided in sequence on the pipeline between the outlet of the slurry pool 5 and the filter press 7. A sixth valve 20 is provided at the water outlet of the filter press 7, and the liquid level gauge 21, the slurry pump 6, the third valve 17, the fourth valve 18 and the sixth valve 20 are all connected to the PLC controller 9.

[0020] A connecting pipe is provided between the water outlet of the slurry pump 6 and the circulating water tank 1 , and a fifth valve 19 is provided on the connecting pipe, and the fifth valve 19 is connected to the PLC controller 9 .

[0021] An application method of a chemical cooling circulating water turbidity control system comprises the following steps: Step 1, a part of the circulating water drawn out from the cooler 3 continues to circulate and cool through the circulating water pool 1, and the other part of the circulating water enters the filter 4 for filtration after the PLC controller 9 controls the opening of the second shut-off valve 14 and the third shut-off valve 15 and the closing of the first shut-off valve 13 and the fourth shut-off valve 16, so that the circulating water is filtered through the filter 4 and then enters the circulating water pool 1 for stable heat exchange and cooling.

[0022] Step 2, select a preset filter 4. When the pressure difference between the second pressure gauge 23 and the third pressure gauge 24 of the filter 4 is greater than the set value, the PLC controller 9 controls the first shut-off valve 13 and the fourth shut-off valve 16 to open, and closes the second shut-off valve 14 and the third shut-off valve 15. The circulating water flows upward from the bottom of the filter 4. After the filter 4 is backwashed for a set time, the slurry water after backwashing enters the slurry pool 5. Then the PLC controller 9 controls the third valve 17, the fourth valve 18 and the sixth valve 20 to open, and closes the fifth valve 19. When the liquid level meter 21 detects the slurry in the slurry pool 5, the liquid level meter 21 detects the slurry in the slurry pool 5. When the water level is not lower than 70% of the capacity of the slurry pool 5, the PLC controller 9 controls the slurry pump 6 to open and transports the slurry water to the filter press 7 for filtration. When the liquid level meter 21 detects that the slurry water level in the slurry pool 5 is not higher than 30% of the capacity of the slurry pool 5, the PLC controller 9 controls the slurry pump 6 to close and stop transporting the slurry water. The slurry circulating water filtered by the filter press 7 flows back into the circulating water pool 1. Then the PLC controller 9 controls the first shut-off valve 13 and the fourth shut-off valve 16 to close, and opens the second shut-off valve 14 and the third shut-off valve 15 at the same time, so that the filter 4 can filter the cooling circulating water normally.

[0023] Step 3, after the filter 4 has gone through the set operating cycle, the PLC controller 9 controls the fourth valve 18 and the sixth valve 20 to close, and the sludge collecting tank 8 of the filter press 7 collects the filtered sludge. At the same time, the fifth valve 19 is opened, and the slurry pump 6 continues to pump the slurry water in the slurry pool 5 to the circulating water pool 1 for recycling.

Claims

1. A chemical cooling circulating water turbidity control system, comprising a circulating water pool (1), a circulating water pump (2) and a cooler (3), wherein the circulating water pool (1), the circulating water pump (2) and the cooler (3) are connected to form a circulating water circuit, and wherein: A filter (4) is connected to the pipeline between the water inlet of the circulating water pool (1) and the cooler (3); the water outlet of the filter (4) is connected to the circulating water pool (1); the water inlet of the filter (4) is also connected to a slurry pool (5); the slurry pool (5) is connected to a filter press (7); and the water outlet of the filter press (7) is connected to the circulating water pool (1).

2. A chemical cooling circulating water turbidity control system according to claim 1, characterized in that: A first shut-off valve (13) is provided on the pipeline between the water inlet of the filter (4) and the slurry pool (5), a second shut-off valve (14) is provided on the pipeline between the water inlet of the filter (4) and the cooler (3), a third shut-off valve (15) is provided on the pipeline between the water outlet of the filter (4) and the circulating water pool (1), a fourth shut-off valve (16) is provided on the pipeline between the water inlet of the second shut-off valve (14) and the water outlet of the filter (4), a second pressure gauge (23) is provided at the water inlet of the filter (4), a third pressure gauge (24) is provided at the water outlet of the filter (4), and the first shut-off valve (13), the second shut-off valve (14), the third shut-off valve (15), the fourth shut-off valve (16), the second pressure gauge (23) and the third pressure gauge (24) are all connected to a PLC controller (9).

3. A chemical cooling circulating water turbidity control system according to claim 2, characterized in that: A liquid level meter (21) is provided in the slurry pool (5); a third valve (17), a slurry pump (6) and a fourth valve (18) are provided in sequence on the pipeline between the outlet of the slurry pool (5) and the filter press (7); a sixth valve (20) is provided at the water outlet of the filter press (7); and the liquid level meter (21), the slurry pump (6), the third valve (17), the fourth valve (18) and the sixth valve (20) are all connected to a PLC controller (9).

4. A chemical cooling circulating water turbidity control system according to claim 3, characterized in that: A connecting pipe is provided between the water outlet of the slurry pump (6) and the circulating water pool (1), a fifth valve (19) is provided on the connecting pipe, and the fifth valve (19) is connected to the PLC controller (9).

5. Also includes an application method of a chemical cooling circulating water turbidity control system, characterized in that: The following steps are involved: Step 1, a portion of the circulating water drawn out from the cooler (3) continues to circulate and cool through the circulating water pool (1), and the other portion of the circulating water enters the filter (4) for filtration after the PLC controller (9) controls the second shut-off valve (14) and the third shut-off valve (15) to open and the first shut-off valve (13) and the fourth shut-off valve (16) to close, so that the circulating water enters the circulating water pool (1) for stable heat exchange and cooling after being filtered through the filter (4); Step 2: When the pressure difference between the second pressure gauge (23) and the third pressure gauge (24) of the filter (4) is greater than the set value, the PLC controller (9) controls the first shut-off valve (13) and the fourth shut-off valve (16) to open, and simultaneously closes the second shut-off valve (14) and the third shut-off valve (15), and the circulating water flows upward from the bottom of the filter (4). After the filter (4) is backwashed for a set time, the slag water after backwashing enters the slag pool (5), and then the PLC controller (9) controls the third valve (17), the fourth valve (18) and the sixth valve (20) to open, and closes the fifth valve (19). When the liquid level meter (21) detects that the slag water level in the slag pool (5) is not lower than When the capacity of the slurry pool (5) reaches 70%, the PLC controller (9) controls the slurry pump (6) to open and deliver the slurry water to the filter press (7) for filtration. When the level meter (21) detects that the slurry water level in the slurry pool (5) is not higher than 30% of the capacity of the slurry pool (5), the PLC controller (9) controls the slurry pump (6) to close and stop delivering the slurry water. The slurry circulating water filtered by the filter press (7) flows back into the circulating water pool (1). Then, the PLC controller (9) controls the first shut-off valve (13) and the fourth shut-off valve (16) to close, and simultaneously opens the second shut-off valve (14) and the third shut-off valve (15), so that the filter (4) can filter the cooling circulating water normally. Step 3: After the filter (4) has completed the set operation cycle, the PLC controller (9) controls the fourth valve (18) and the sixth valve (20) to close, and the filter press (7) collects the filtered sludge. At the same time, the fifth valve (19) is opened, and the slurry pump (6) continues to pump the slurry water in the slurry pool (5) into the circulating water pool (1) for recycling.

Images