Air resistance eliminating device for water outlet pipeline of ozone oxidation tower

Abstract

A device for eliminating air resistance of a water outlet pipeline of an ozone oxidation tower comprises the ozone oxidation tower and a post-reaction tank, the top of the ozone oxidation tower is communicated with an exhaust pipe, the upper portion of the ozone oxidation tower is communicated with a water inlet pipe, the bottom of the ozone oxidation tower is communicated with an air inlet pipe, and the post-reaction tank is communicated with the ozone oxidation tower through a water outlet pipeline. The water outlet pipeline is an inverted-U-shaped water outlet pipe, the inverted-U-shaped water outlet pipe comprises an inverted-U-shaped water outlet pipe ascending pipe and an inverted-U-shaped water outlet pipe descending pipe which are communicated with each other, the inverted-U-shaped water outlet pipe descending pipe is communicated with a ventilation vertical pipe, the ventilation vertical pipe is communicated with the exhaust pipe, and a plurality of airflow guide pipes are further communicated between the ventilation vertical pipe and the inverted-U-shaped water outlet pipe descending pipe; the exhaust pipe is externally connected with a tail gas treatment unit, and a breather valve is further installed on the top of the ozone oxidation tower. According to the utility model, the problem of water outlet air resistance in actual engineering can be well solved, so that the condition of unsmooth water flow or overflow can be avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of sewage treatment, in particular to a device for eliminating air blockage in a water outlet pipeline of an ozone oxidation tower. Background Art

[0002] Ozone oxidation towers are widely used in industrial wastewater treatment. In order to make the gas and liquid fully contact, a gas-liquid countercurrent contact oxidation tower is often used, that is, the gas is distributed at the bottom of the tower and the gas is discharged at the top of the tower, and the water is distributed at the top of the tower and the water is discharged at the bottom of the tower. The outlet pipe of the gas-liquid countercurrent contact oxidation tower is at the bottom of the tower. In order to maintain the liquid level in the tower, the outlet pipe is bent upward to the liquid level in the tower, and then bent downward to enter the post-reaction tank. However, this form causes the outlet pipe to form an inverted U shape. When gas accumulates in the water flow down section of the inverted U-shaped pipe, it is easy to form air resistance and cause poor water flow. In order to reduce the air resistance in the inverted U-shaped pipe, the usual practice is to add an upward vent pipe at the highest point of the water flow down section. When the oxidation tower and the post-reaction tank are continuously running through water, the outlet pipe is always in a state of not being full of water but being able to exhaust or in a state of being full of water, and the water flow is smooth; but in actual engineering operation, the water inlet often fluctuates, resulting in intermittent operation of the oxidation tower or a state of instantaneous flow increase.

[0003] When the oxidation tower is stopped, the rising section of the outlet pipe is filled with water, the upper section of the outlet pipe is filled with air, and the lower section of the outlet pipe is filled with water. When the oxidation tower is started again, if the water flow is small, the upper section of the downpipe is in a wall-attached spiral flow or water film flow state, which can slowly remove the air in the pipe, and there is no air resistance at this time; but in practice, the water inlet flow of the oxidation tower usually fluctuates according to the staged start-up of the water inlet pump. When the pump is started, it causes an instantaneous increase in flow, and the air in the upper section of the downpipe is not removed in time to form an air column. The water flow is in the form of water plug flow, and the water flow is not smooth and even overflows from the ventilation pipe out of the system. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide an ozone oxidation tower outlet pipe air blockage elimination device which can solve the outlet air blockage problem existing in actual engineering and avoid the occurrence of poor water flow or overflow.

[0005] The technical problem to be solved by the utility model is achieved through the following technical solutions. The utility model is an ozone oxidation tower outlet pipe air blockage elimination device, including an ozone oxidation tower and a post-reaction tank, an exhaust pipe is connected at the top of the ozone oxidation tower, an inlet pipe is connected at the upper part of the ozone oxidation tower, an air inlet pipe is connected at the bottom of the ozone oxidation tower, the post-reaction tank is connected with the ozone oxidation tower through an outlet pipe, the outlet pipe is an inverted U-shaped outlet pipe, the inverted U-shaped outlet pipe includes an inverted U-shaped outlet pipe riser and an inverted U-shaped outlet pipe downcomer that are interconnected, a ventilation riser is connected on the inverted U-shaped outlet pipe downcomer, the ventilation riser is connected with the exhaust pipe, and a plurality of airflow ducts are also connected between the ventilation riser and the inverted U-shaped outlet pipe downcomer.

[0006] The technical problem to be solved by the utility model can also be further achieved through the following technical scheme. For the above-mentioned ozone oxidation tower water outlet pipe air blockage elimination device, the exhaust pipe is externally connected to the exhaust gas treatment unit, and a breathing valve is also installed on the top of the ozone oxidation tower.

[0007] The technical problem to be solved by the utility model can also be further achieved through the following technical scheme. For the above-mentioned ozone oxidation tower outlet pipe air blockage elimination device, the inverted U-shaped outlet pipe downcomer is divided into an upper downcomer section and a lower downcomer section according to the liquid level height of the reaction tank. The inverted U-shaped outlet pipe downcomer above the liquid level height is the upper downcomer section, and the inverted U-shaped outlet pipe downcomer below the liquid level height is the lower downcomer section, and the airflow duct is arranged in the upper downcomer section.

[0008] The technical problem to be solved by the utility model can be further achieved through the following technical scheme. For the above-mentioned ozone oxidation tower outlet pipe air blockage elimination device, the air flow duct is arranged above the connection point between the ventilation riser and the inverted U-shaped outlet pipe downcomer.

[0009] The technical problem to be solved by the utility model can also be further achieved through the following technical scheme. For the above-mentioned ozone oxidation tower outlet pipe air blockage elimination device, the air flow duct is arranged at a height higher than the liquid level of the post-reaction tank at the connection point between the ventilation riser and the inverted U-shaped outlet pipe downcomer.

[0010] The technical problem to be solved by the utility model can also be further achieved through the following technical scheme. For the above-mentioned ozone oxidation tower outlet pipe air blockage elimination device, the air flow duct is arranged at a height higher than the liquid level of the post-reaction tank by 20~50cm at the connecting point of the ventilation riser and the inverted U-shaped outlet pipe downcomer, and the spacing between adjacent air flow ducts is 1~2m.

[0011] The technical problem to be solved by the utility model can also be further achieved through the following technical solutions. For the above-mentioned ozone oxidation tower outlet pipe air blockage elimination device, the air flow duct is an H pipe fitting, a combined ventilation pipe, an oblique tee or an inclined pipe.

[0012] Compared with the prior art, the utility model has the following beneficial effects:

[0013] The utility model can solve the problem of water plug flow air resistance in the water outlet pipe of the ozone oxidation tower. When there is an air column in the water outlet downcomer of the ozone oxidation tower, the utility model can effectively remove the air in the air column. It is suitable for exhausting the ozone oxidation tower at the start-up stage, and for exhausting the ozone oxidation tower when the front lifting pump is designed for staged operation and the pump is suddenly started.

[0014] Secondly, when the water inlet flow rate of the ozone oxidation tower increases instantaneously, the gas in the upper section of the downcomer is suddenly compressed. Regardless of whether the flow state of water in the downcomer of the inverted U-shaped outlet pipe is wall-attached spiral flow, water film flow or water plug flow, the compressed or restricted gas can pass through the air flow duct and be discharged from the ventilation riser to ensure smooth water flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the utility model;

[0016] Figure 2 yes Figure 1 The enlarged view of point A in the middle;

[0017] Figure 3 It is a schematic diagram of the utility model using a combined vent pipe;

[0018] Reference numerals:

[0019] 11: Ozone oxidation tower; 12: Post-reaction tank; 13: Oxidation tower water inlet pipe; 14: Ozonation gas inlet pipe; 15: Oxidation tower exhaust pipe; 16: Breathing valve; 17: Tail gas treatment unit; 21: Inverted U-shaped water outlet pipe riser; 22: Inverted U-shaped water outlet pipe downpipe upper section; 23: Inverted U-shaped water outlet pipe downpipe lower section; 24: H pipe fitting; 25: Ventilation riser; 31: Combined ventilation pipe. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] Reference Figure 1-3 , a device for eliminating air blockage in a water outlet pipe of an ozone oxidation tower 11, comprising an ozone oxidation tower 11 and a post-reaction tank 12, wherein an exhaust pipe 15 is connected to the top of the ozone oxidation tower 11 for exhausting the ozone oxidation tower 11, and in order to treat the tail gas, the exhaust pipe 15 is externally connected to a tail gas treatment unit 17, and at the same time, the tail gas treatment unit 17 maintains a slightly negative pressure state in the oxidation tower through a fan suction, and in order to ensure safety, a breathing valve 16 is also installed on the top of the ozone oxidation tower 11;

[0022] The upper part of the ozone oxidation tower 11 is connected with a water inlet pipe 13 for realizing the water inlet operation of the ozone oxidation tower 11, and the bottom of the ozone oxidation tower 11 is connected with an air inlet pipe 14 for realizing the air inlet operation of the ozone oxidation tower 11. The post-reaction tank 12 is connected with the ozone oxidation tower 11 through a water outlet pipe, which is used to transport the effluent of the ozone oxidation tower 11 to the post-reaction tank 12. Specifically:

[0023] The water outlet pipe is an inverted U-shaped water outlet pipe, which includes an inverted U-shaped water outlet pipe riser 21 and an inverted U-shaped water outlet pipe downcomer that are interconnected. A ventilation riser 25 is connected to the inverted U-shaped water outlet pipe downcomer. The ventilation riser 25 is connected to the exhaust pipe 15, so that the gas discharged through the ventilation riser 25 can enter the exhaust pipe 15, and finally be treated by the exhaust gas treatment unit 17 before being discharged to the outside, without generating secondary gas pollution. A number of airflow ducts are also connected between the ventilation riser 25 and the inverted U-shaped water outlet pipe downcomer. The inverted U-shaped water outlet pipe is used to maintain the liquid level in the ozone oxidation tower 11, and the ventilation riser 25 is used to realize the exhaust operation and play a role in removing air resistance. The airflow duct is used to better remove air resistance and avoid poor water flow or even overflow from the ventilation pipe out of the system. There can be multiple airflow ducts, generally 3-5.

[0024] Preferably, the inverted U-shaped outlet pipe downcomer is divided into an upper downcomer section 22 and a lower downcomer section 23 according to the liquid level height of the reaction tank 12. The inverted U-shaped outlet pipe downcomer above the liquid level is the upper downcomer section 22, and the inverted U-shaped outlet pipe downcomer below the liquid level is the lower downcomer section 23. The airflow conduit is arranged at the upper downcomer section 22.

[0025] The air flow duct is arranged above the connection between the ventilation riser 25 and the inverted U-shaped water outlet pipe downcomer, so as to better remove the air resistance. Preferably, the air flow duct is arranged at a height higher than the liquid level of the post-reaction tank 12 at the connection between the ventilation riser 25 and the inverted U-shaped water outlet pipe downcomer. Further preferably, the air flow duct is arranged at a height higher than the liquid level of the post-reaction tank 12 at the connection between the ventilation riser 25 and the inverted U-shaped water outlet pipe downcomer, and the spacing between adjacent air flow ducts is 1 to 2 meters.

[0026] The air flow duct is an H pipe fitting 24, a combined vent pipe 31, an oblique tee or an inclined pipe. Generally, when the pipe diameter is greater than 200 mm, the H pipe fitting 24 can be replaced by a combined vent pipe 31, and the combined vent pipe 31 is made of pipes and pipe fittings.

[0027] In actual use, the top horizontal pipe section of the inverted U-shaped water outlet pipe is at the same height as the liquid level of the ozone oxidation tower 11, and the liquid level of the post-reaction tank 12 is lower than the liquid level of the ozone oxidation tower 11. When the ozone oxidation tower 11 is running at low water volume or not running, the U-shaped water outlet pipe, the water outlet pipe riser and the lower section 23 of the downcomer are in a water-filled state, and the horizontal pipe section of the U-shaped water outlet pipe and the upper section 22 of the downcomer are in a non-water-filled or water-free state.

[0028] Water flow status in the U-shaped outlet pipe downcomer:

[0029] As the drainage flow in the downcomer increases, the water flow state in the downcomer mainly goes through three stages: wall-attached spiral flow, water film flow and water plug flow:

[0030] (1) Wall-attached spiral flow

[0031] When the water volume is small, the water entering the downcomer flows downward in a spiral along the inner wall of the pipe. The centrifugal force generated by the spiral motion makes the water flow dense, the gas-liquid interface clear, and the air entrainment effect of the water flow is not obvious. The air flow in the center of the downcomer is normal and the air pressure in the pipe is stable. With the increase of the drainage volume, when the water volume is enough to cover the entire wall of the downcomer, the water flow is in a state of wall-attached downward flow. Because the drainage volume is small, the air flow in the center of the pipe is still normal and the air pressure is relatively stable.

[0032] (2) Water film flow

[0033] When the water volume increases further, the water flows down along the pipe wall, forming a wall-attached annular water film flow with a certain thickness and a transverse diaphragm. After the annular water film is formed, it accelerates downward. The thickness of the water film is approximately proportional to the falling speed. As the falling speed of the water increases, the friction force of the pipe wall on the water film also increases. When the upward friction force on the water film reaches a balance with the gravity, the falling speed and thickness of the water film no longer change. The flow rate at this time is called the terminal flow rate (νt), and the height from the top of the downcomer to the point where the terminal flow rate is formed is called the terminal length (Lt);

[0034] During the downward movement of water, the pressure in the tube below the diaphragm increases continuously. When the pressure reaches a certain value, the gas in the tube breaks through the transverse diaphragm, and the air pressure in the tube returns to normal. In the process of continuing to descend, a new transverse diaphragm is formed. The formation and destruction of the transverse diaphragm are carried out alternately. In the water film flow stage, the water filling rate in the downcomer is 1 / 4~1 / 3. Although the air pressure in the downcomer fluctuates, water can still pass through, and the drainage capacity at this time is the maximum drainage flow of the downcomer.

[0035] (3) Water plug flow

[0036] As the drainage volume continues to increase, when the water filling rate exceeds 1 / 3, the formation and destruction of the transverse diaphragm become more and more frequent, the water film thickness continues to increase, and the pressure under the diaphragm cannot break through the water film, and finally a relatively stable water plug is formed. After the water plug is formed, it is difficult for the downcomer to discharge water.

[0037] When the water flow rate of the ozone oxidation tower increases instantaneously, the gas in the upper section of the downcomer is suddenly compressed. Regardless of whether the flow state of water in the downcomer of the inverted U-shaped outlet pipe is wall-attached spiral flow, water film flow or water plug flow, the compressed or restricted gas can pass through the air flow duct and be discharged from the ventilation riser, ensuring smooth water flow in the inverted U-shaped outlet pipe.

Claims

1. An ozone oxidation tower outlet pipe air blockage elimination device, characterized in that: The invention comprises an ozone oxidation tower and a post-reaction tank, wherein an exhaust pipe is connected to the top of the ozone oxidation tower, an inlet pipe is connected to the upper part of the ozone oxidation tower, an air inlet pipe is connected to the bottom of the ozone oxidation tower, the post-reaction tank is connected to the ozone oxidation tower through an outlet pipe, the outlet pipe is an inverted U-shaped outlet pipe, the inverted U-shaped outlet pipe comprises an inverted U-shaped outlet pipe riser and an inverted U-shaped outlet pipe downcomer which are interconnected, a ventilation riser is connected to the inverted U-shaped outlet pipe downcomer, the ventilation riser is connected to the exhaust pipe, and a plurality of air flow ducts are also connected between the ventilation riser and the inverted U-shaped outlet pipe downcomer.

2. The device for eliminating air blockage in the outlet pipe of the ozone oxidation tower according to claim 1, characterized in that: The exhaust pipe is externally connected to a tail gas treatment unit, and a breathing valve is also installed on the top of the ozone oxidation tower.

3. The device for eliminating air blockage in the outlet pipe of the ozone oxidation tower according to claim 1, characterized in that: The inverted U-shaped water outlet pipe downcomer is divided into an upper downcomer section and a lower downcomer section according to the liquid level height of the reaction tank. The inverted U-shaped water outlet pipe downcomer above the liquid level height is the upper downcomer section, and the inverted U-shaped water outlet pipe downcomer below the liquid level height is the lower downcomer section. The airflow duct is arranged in the upper downcomer section.

4. The device for eliminating air blockage in the outlet pipe of the ozone oxidation tower according to claim 1, characterized in that: The airflow duct is arranged above the connection point between the ventilation riser and the inverted U-shaped water outlet pipe downcomer.

5. The device for eliminating air blockage in the outlet pipe of the ozone oxidation tower according to claim 4, characterized in that: The height of the airflow duct arranged at the connection point between the ventilation riser and the inverted U-shaped water outlet pipe downcomer is higher than the liquid level of the post-reaction tank.

6. The device for eliminating air blockage in the outlet pipe of the ozone oxidation tower according to claim 5, characterized in that: The airflow duct is arranged at a height of 20-50 cm higher than the liquid level of the post-reaction tank at the connection point between the ventilation riser and the inverted U-shaped outlet pipe downcomer, and the spacing between adjacent airflow ducts is 1-2 m.

7. The device for eliminating air blockage in the outlet pipe of the ozone oxidation tower according to claim 1, characterized in that: The airflow duct is an H pipe fitting, a combined vent pipe, an oblique tee or an inclined pipe.

Images