CN215327554U

CN215327554U - Intermittent type formula denitrification allies oneself with uses AO method advanced treatment high nitrate nitrogen effluent device

Info

Publication number: CN215327554U
Application number: CN202120880161.XU
Authority: CN
Inventors: 何成达; 魏世勋; 吴凡; 刘金辉; 潘怡欣
Original assignee: Yangzhou University
Current assignee: Yangzhou University
Priority date: 2021-04-27
Filing date: 2021-04-27
Publication date: 2021-12-28
Anticipated expiration: 2031-04-27

Abstract

The utility model discloses a device for advanced treatment of high nitrate nitrogen wastewater by an intermittent denitrification combined AO method, which belongs to the technical field of biological wastewater treatment, and is formed by sequentially connecting an intermittent denitrification area, an intermediate water tank and an AO process area in series, wherein the removal rate of nitrate nitrogen in the intermittent denitrification area reaches 87%, the removal rate of COD (chemical oxygen demand) reaches 90%, the removal rate of ammonia nitrogen in the AO process area reaches 95%, the removal rate of total nitrogen reaches 89%, and the removal rate of COD reaches 76% by combining the intermittent denitrification method and the AO process. Can remove pollutants such as ammonia nitrogen, COD and the like in water while removing high-concentration nitrate nitrogen. The continuous stability of the device can be ensured by controlling the timer and the peristaltic pump. The adjustment to timer and peristaltic pump can carry out the processing of pertinence to waste water, and the flexibility is high, easy operation, and maintenance management is convenient.

Description

Intermittent type formula denitrification allies oneself with uses AO method advanced treatment high nitrate nitrogen effluent device

Technical Field

The utility model belongs to the technical field of biological sewage treatment, particularly relates to a treatment device for advanced treatment of high nitrate nitrogen wastewater, and particularly relates to a device for advanced treatment of high nitrate nitrogen wastewater by an intermittent denitrification combined AO method.

Background

With the development and progress of economy in China, the initial stage of wastewater discharged by enterprises in production is not taken into consideration, so that the content of nitrogen elements in various water bodies (including drinking water sources) is continuously increased, wherein nitrate nitrogen pollution caused by high-concentration nitrate nitrogen wastewater mainly from industrial production is common, and the caused harm is serious. The current research treatment of nitrate nitrogen has received extensive attention.

The increase of the nitrogen content in the water body can cause eutrophication of the water body, which leads to the generation of red tide and death of animals and plants. In the later 90 s of the 20 th century, lakes with eutrophication in China already account for 77% of the total amount of investigation. The outbreak of blue algae in the Taihu lake in 2007 makes people pay attention to the problem of water eutrophication by knocking the alarm clock. Nitrate ions in nitrate nitrogen can be changed into nitrate, nitrite and the like under the action of nitrifying bacteria after entering a water body along with wastewater. Nitrite nitrogen is extremely toxic, and excess nitrite can directly poison people. Nitrate nitrogen and nitrite nitrogen are both chemically stable and thus are difficult to absorb and degrade, and may be present in the human body for a long time to induce various diseases.

At present, the most used denitrification technology at home and abroad is a biological method, the cost is low, no special structure is needed, and secondary pollution is not easy to cause. Among biological methods, an A/O method, an A/A/O method and the like have good treatment effect on low-concentration nitrate nitrogen wastewater (less than 600mg/L), and are suitable for large-scale water treatment. But the treatment of the high-concentration nitrate nitrogen wastewater (more than 600mg/L) is not ideal.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a device for advanced treatment of high nitrate nitrogen wastewater by an AO method in combination with intermittent denitrification, aiming at the defects in the prior art, the device can remove a large amount of high-concentration nitrate nitrogen in wastewater and pollutants such as ammonia nitrogen, COD and the like in the wastewater, can ensure continuous and more stable automatic operation of the device by controlling a timer and a peristaltic pump, can perform targeted treatment on the wastewater by adjusting the timer and the peristaltic pump, and has the advantages of high flexibility, simple operation and convenient maintenance and management.

The technical scheme of the utility model is as follows: the utility model provides a device for advanced treatment of high nitrate nitrogen wastewater by an AO method is used in batch type denitrification, which is characterized in that: the device for advanced treatment of high nitrate nitrogen wastewater by an intermittent denitrification method combined with an AO process is formed by sequentially connecting an intermittent denitrification area, an intermediate water tank and an AO process area in series; the denitrification zone is formed by connecting a raw water tank, a first peristaltic pump and a denitrification reactor in sequence, and a first stirring paddle is arranged in the denitrification reactor; the AO process area is connected by anoxic reactor, aerobic reactor, sedimentation tank and play water tank in proper order and constitutes, be equipped with third peristaltic pump and fourth peristaltic pump between anoxic reactor and the aerobic reactor, be equipped with the fifth peristaltic pump between aerobic reactor and the sedimentation tank, be equipped with the second stirring rake in the anoxic reactor, denitrification reactor is connected with the input of intermediate water tank, the output and the anoxic reactor of intermediate water tank are connected.

An aerator is arranged at the bottom of the aerobic reactor.

The third peristaltic pump is arranged on a pipeline between the anoxic reactor and the aerobic reactor; the fourth peristaltic pump is arranged on a pipeline from the aerobic reactor to the anoxic reactor.

The utility model has the beneficial effects that: the utility model provides a device for advanced treatment of high nitrate nitrogen wastewater by an intermittent denitrification combined AO method, which is formed by sequentially connecting an intermittent denitrification area, an intermediate water tank and an AO process area in series, wherein the removal rate of nitrate nitrogen in the intermittent denitrification area reaches 87%, the removal rate of COD (chemical oxygen demand) reaches 90%, the removal rate of ammonia nitrogen in the AO process area reaches 95%, the removal rate of total nitrogen reaches 89%, the removal rate of COD reaches 76%, and the final effluent quality can reach the indirect discharge standard of electronic special material wastewater. The device of the utility model can remove a large amount of high-concentration nitrate nitrogen contained in the wastewater. Can remove pollutants such as ammonia nitrogen, COD and the like in water while removing high-concentration nitrate nitrogen. Through controlling timer and peristaltic pump, can guarantee the continuous stability of device, can carry out the processing of pertinence to waste water to the regulation of timer and peristaltic pump, the flexibility is high, easy operation, and maintenance management is convenient.

Drawings

FIG. 1 is a schematic diagram of the structure and working principle of the device of the present invention.

In the figure: the system comprises an intermittent denitrification zone 1, an AO process zone 2, a raw water tank 3-1, an intermediate water tank 3-2, a water outlet tank 3-3, a first peristaltic pump 4-1, a second peristaltic pump 4-2, a third peristaltic pump 4-3, a fourth peristaltic pump 4-4, a fifth peristaltic pump 4-5, a sixth peristaltic pump 4-6, a first stirring paddle 5-1, a second stirring paddle 5-2, a denitrification reactor 6, an anoxic reactor 7, an aerobic reactor 8, a sedimentation tank 9 and an aerator 10.

Detailed Description

The utility model will be further described with reference to the accompanying drawings in which:

as shown in figure 1, the device for advanced treatment of high nitrate nitrogen wastewater by an intermittent denitrification combined AO method is formed by sequentially connecting an intermittent denitrification area 1, an intermediate water tank 3-2 and an AO process area 2 in series; the denitrification area 1 is formed by connecting a raw water tank 3-1, a first peristaltic pump 4-1 and a denitrification reactor 6 in sequence, and a first stirring paddle 5-1 is arranged in the denitrification reactor 6; the AO process area 2 is formed by connecting an anoxic reactor 7, an aerobic reactor 8, a sedimentation tank 9 and a water outlet tank 3-3 in sequence, a third peristaltic pump 4-3 and a fourth peristaltic pump 4-4 are arranged between the anoxic reactor 7 and the aerobic reactor 8, a fifth peristaltic pump 4-5 is arranged between the aerobic reactor 8 and the sedimentation tank 9, a second stirring paddle 5-2 is arranged in the anoxic reactor 7, a denitrification reactor 6 is connected with the input end of the intermediate water tank 3-2, and the output end of the intermediate water tank 3-2 is connected with the anoxic reactor 7.

As shown in figure 1, the device for advanced treatment of high nitrate nitrogen wastewater by an AO method in combination with intermittent denitrification is characterized in that a stirring paddle 5-1 is opened only in the stirring stage of a denitrification reactor 6, is closed in the rest time, a stirring paddle 5-2 is continuously operated, and an aerator 10 continuously provides aeration for an aerobic reactor 8. The intermittent denitrification method is combined with the AO process, the concentration of nitrate nitrogen in water is greatly reduced through an intermittent denitrification area 1, and most of ammonia nitrogen, nitrate nitrogen and nitrite nitrogen in water are removed through further advanced treatment in an AO process area 2.

As shown in figure 1, the treatment working principle of the device for advanced treatment of high nitrate nitrogen wastewater by an intermittent denitrification combined AO method is as follows:

(1) a certain amount of wastewater (C/N =3-4) is introduced into a raw water tank 3-1, the wastewater is pumped into a denitrification reactor 6 of an intermittent denitrification area 1 through a peristaltic pump 4-1, one period of the intermittent denitrification comprises four stages of water feeding, stirring, standing and water discharging, and a stirring paddle 5-1 only runs at a stirring stage under the control of a timer, and the rotating speed is 50 r/min. Half of the water amount of the reactor is removed from the discharged water in each period, half of the water amount of the fed water is added into the reactor, the hydraulic retention time is 10 hours, the water inlet and outlet time is controlled by a timer, wherein the stirring stage is 3 hours, the standing is 1 hour, the water inlet and outlet time is 1 hour, and the sludge concentration is 3500 mg/L. The denitrifying bacteria perform denitrification by taking organic matters in the wastewater as a carbon source, and remove a large amount of nitrate nitrogen and nitrite nitrogen in the water.

(2) The intermittent denitrification effluent freely flows into the intermediate water tank 3-2 by gravity in the effluent stage.

(3) The wastewater in the intermediate water tank 3-2 and the sludge returned from the settling zone 9 are pumped into an anoxic reactor 7 of the AO process zone 2 together through a peristaltic pump 4-2, the sludge reflux ratio is 100%, the nitrified liquid flows back 200%, the anoxic reaction is carried out by the continuous operation of a stirring paddle 5-2, the rotating speed is 50r/min, the sludge concentration is 3500mg/L, and the hydraulic retention time is 10 h.

(4) After the anaerobic reaction, the wastewater is continuously pumped into an aerobic reactor 8 by a peristaltic pump 4-3, an aeration machine 10 continuously provides an air flow of 0.4L/min to maintain the aerobic reaction, the nitrified liquid flows back to an anoxic reactor 7 by the peristaltic pump 4-4, the sludge concentration is 3500mg/L, and a small amount of ammonia nitrogen and nitrate nitrogen are further removed in the AO process stage.

(5) After aerobic reaction, the wastewater is continuously pumped into a settling zone 9 by a peristaltic pump 4-5, the sludge after standing and settling is pumped back to an anoxic reactor 7 by the peristaltic pump 4-6, and supernatant freely flows into an effluent water tank 3-3 by gravity.

The industrial wastewater is adopted in the implementation mode, and the main water quality characteristics are as follows: nitrate nitrogen (1510 +/-20) mg/L, nitrite nitrogen (51.8 +/-1.2) mg/L, ammonia nitrogen (47.22 +/-1.9) mg/L and COD (5320 +/-80) mg/L; after the treatment of the intermittent denitrification zone, the main water quality indexes change as follows: total nitrogen (287.5 +/-3.1) mg/L, ammonia nitrogen (37.8 +/-0.6) mg/L and COD (1195 +/-8.9) mg/L; the effluent water quality index after advanced treatment by the AO process is as follows: total nitrogen (29.56 +/-0.8) mg/L, ammonia nitrogen (1.82 +/-0.1) mg/L and COD (282.4 +/-5.6) mg/L.

Treatment embodiment 1

The C/N in the raw water tank 3-1 is artificially controlled to be 3.5, raw water is rapidly pumped into the denitrification reactor 6 by the peristaltic pump 4-1 under the water inlet state of the denitrification reactor 6, and the water volume is half of the effective volume of the denitrification reactor 6. Setting a denitrification reactor 6 in a stirring stage for 3 hours, standing for 1 hour, feeding water for 0.5 hour, discharging water for 0.5 hour, wherein the sludge concentration is 3500mg/L, and a stirring paddle only operates in the stirring stage at the rotating speed of 50 r/min. The water outlet is arranged at the half height of the effective water depth of the denitrification reactor 6, the water valve is controlled to be opened by the timer in the water outlet stage, and the water freely flows into the middle water tank 3-2 by gravity.

Treatment embodiment 2

Setting the flow rate of a peristaltic pump 4-2 as 500ml/h, continuously pumping the mixture into an anoxic reactor 7 from an intermediate water tank 3-2, and carrying out anoxic denitrification reaction in the anoxic reactor 7 under the continuous operation of a stirring paddle 5-2, wherein the rotating speed is 50r/min, and the sludge concentration is 3500 mg/L. The nitrifying liquid is continuously pumped into the anoxic reactor 7 at a reflux rate of 200%, a flow rate of 1000ml/h through the peristaltic pump 4-4 and a sludge reflux rate of 100% and a flow rate of 500ml/h through the peristaltic pump 4-6. After the anoxic reaction, the sludge is pumped into an aerobic reactor 8 by a peristaltic pump 4-3 at 2000ml/h, and the aerobic reaction is maintained by continuously providing air quantity of 0.4L/min by an aerator 10, wherein the sludge concentration is 3500 mg/L. After aerobic reaction, the sewage is pumped into a settling zone 9 at a flow rate of 1000ml/h by a peristaltic pump 4-5, and the sewage overflows from the upper part at a flow rate of 500ml/h and flows into a sewage tank 3-3 by gravity.

Claims

1. The utility model provides a device for advanced treatment of high nitrate nitrogen wastewater by an AO method is used in batch type denitrification, which is characterized in that: the device for advanced treatment of high nitrate nitrogen wastewater by using the intermittent denitrification method and the AO process is formed by sequentially connecting an intermittent denitrification area (1), an intermediate water tank (3-2) and an AO process area (2) in series; the denitrification zone (1) is formed by connecting a raw water tank (3-1), a first peristaltic pump (4-1) and a denitrification reactor (6) in sequence, and a first stirring paddle (5-1) is arranged in the denitrification reactor (6); the AO process area (2) is connected by anoxic reactor (7), aerobic reactor (8), sedimentation tank (9) and play water tank (3-3) in proper order and constitutes, be equipped with third peristaltic pump (4-3) and fourth peristaltic pump (4-4) between anoxic reactor (7) and aerobic reactor (8), be equipped with fifth peristaltic pump (4-5) between aerobic reactor (8) and sedimentation tank (9), be equipped with second stirring rake (5-2) in anoxic reactor (7), denitrification reactor (6) is connected with the input of intermediate water tank (3-2), the output of intermediate water tank (3-2) is connected with anoxic reactor (7).

2. The device for advanced treatment of high nitrate nitrogen wastewater by using the intermittent denitrification combined AO method according to claim 1, is characterized in that: an aerator (10) is arranged at the bottom of the aerobic reactor (8).

3. The device for advanced treatment of high nitrate nitrogen wastewater by using the intermittent denitrification combined AO method according to claim 1, is characterized in that: the third peristaltic pump (4-3) is arranged on a pipeline between the anoxic reactor (7) and the aerobic reactor (8); the fourth peristaltic pump (4-4) is arranged on a pipeline from the aerobic reactor (8) to the anoxic reactor (7).