CN111450616A - Efficient activated sludge interception type secondary sedimentation tank process system with coupling depth filtering function - Google Patents

Abstract

A high-efficiency activated sludge retention type secondary sedimentation tank process system with coupled depth filtering The mud retention type secondary sedimentation tank includes a tank body, a water inlet pipe, a water distribution system, an overflow weir, a slag baffle, a slag scraper, a mud scraper, a driving motor, a stirring device and a coupled filter tank. The system has the functions of mesh replenishment, flocculation sedimentation and filtration, and takes into account the functions of mud-water separation, chemical phosphorus removal and deep filtration, which can significantly improve the mud-water separation effect of the secondary sedimentation tank, reduce the hydraulic retention time and land occupation of the secondary sedimentation tank, and couple the depth of The filtration system not only saves the energy consumption of the secondary lifting, but also saves the corresponding sewage pipeline.

Description

High-efficiency activated sludge retention type secondary sedimentation tank process with coupled depth filtration function system

technical field

The invention belongs to the technical field of sewage treatment, and in particular relates to a high-efficiency activated sludge retention type secondary sedimentation tank process system with a coupling depth filtration function.

Background technique

Summarizing the experience of upgrading and transformation of sewage treatment plants in my country in the past ten years, the biggest problem commonly encountered is the limited floor space, and the construction land of the existing sewage treatment plants cannot meet the actual needs of upgrading and transformation, which seriously restricts the development of sewage treatment plants. , and the area of the secondary sedimentation tank accounts for 10% to 20% of the process system; secondly, the sewage pipe network of my country's sewage treatment plants is mainly a confluence system. The load seriously exceeds the design standard, and the stable operation of the sewage treatment plant process is seriously threatened. One of the most prominent problems is the insufficient surface load of the secondary sedimentation tank.

At the same time, it was found that the effluent from the secondary sedimentation tank of most sewage treatment plants to the filtration system for subsequent advanced treatment requires a second upgrade, and the energy consumption of the second upgrade accounts for more than 10% of the energy consumption of sewage treatment. Energy saving is advocated in my country. Under the background of the goal of reducing consumption and improving quality and efficiency, the saving of this part of energy consumption is also crucial.

When land resources are limited, the influent water volume of the combined pipe network fluctuates, and the energy consumption for secondary improvement from secondary treatment of sewage to advanced treatment becomes an important factor affecting the quality and efficiency of urban sewage treatment plants, the operation efficiency of the secondary sedimentation tank will increase. Upgrading is an important measure to reduce land occupation, cope with fluctuations in influent water volume, save energy and reduce consumption, and it needs to be solved urgently.

SUMMARY OF THE INVENTION

The purpose of the invention is to overcome the shortcomings of low operating efficiency and large footprint of traditional secondary sedimentation tanks, and to provide a high-efficiency activated sludge retention type secondary sedimentation tank process system with coupled depth filtration function. It can significantly improve the mud-water separation effect of the secondary sedimentation tank, reduce the hydraulic retention time and land occupation of the secondary sedimentation tank, and couple the depth filtration system, which not only saves secondary sedimentation Improve energy consumption and save the corresponding sewage pipeline.

As conceived above, the technical scheme of the present invention is: a high-efficiency activated sludge retention type secondary sedimentation tank process system with coupled depth filtration function, including a water distribution system, characterized in that: the water distribution system and the coupled depth filtration function High-efficiency activated sludge The sludge retention type secondary sedimentation tank is connected, and the high-efficiency activated sludge retention type secondary sedimentation tank with coupled depth filtration function includes a tank body, a water inlet pipe, a water distribution system, an overflow weir, a slag baffle, a slag scraper, and a sludge scraper. A plate, a driving motor, a stirring device and a coupled filter tank, the water inlet pipe is installed vertically at the center of the tank body and a driving motor is installed on the top thereof, the water distribution system surrounds the water inlet pipe, and the stirring device is installed in the tank On the inner wall of the body, the overflow weir is arranged on the water surface inside the pool body and an overflow port is made outside the overflow weir, the slag baffle plate is arranged inside the overflow weir, and the slag scraper is arranged on the upper part of the pool body At the water surface, the scraper is arranged at the bottom of the pool body, and both the slag scraper and the scraper are connected to the drive motor. The coupled filter pool is arranged around the pool body and communicated with the overflow port. The bottom end of the pool body is provided with a sludge discharge/sludge return port, and the water distribution system is communicated with the water inlet pipe.

The water distribution system is externally connected with a dosing system.

The overflow weir has a zigzag structure and is annularly arranged at the water surface inside the tank body.

The working principle of the invention is as follows: the mud-water mixture of the biological system enters the water inlet pipe of the secondary sedimentation tank, enters the water distribution system of the secondary sedimentation tank through the water inlet pipe, and the mixed liquid enters the middle and lower parts of the secondary sedimentation tank through the water distribution system and is formed by the stirring system. The retention and adsorption of suspended activated sludge layers with different high and low densities quickly intercept the activated sludge in the mixed solution, and the activated sludge with high density enters the sludge hopper at the bottom of the secondary sedimentation tank through sedimentation, and a part of it can pass through. The internal return pump returns to the biological treatment system, and the other part is discharged out of the tank through the sludge discharge equipment at the bottom of the secondary sedimentation tank and enters the subsequent sludge treatment system. Located in the upper part of the secondary sedimentation tank is the supernatant liquid after the separation of mud and water, and the supernatant liquid flows into the depth filtration system (coupled filter tank) by gravity to further remove the suspended solids in the supernatant liquid.

The hydraulic retention time of the above process system is 1.5-2.5 hours, and the residence time of activated sludge is controlled within 10 hours, which can be controlled comprehensively by the return pump and the sludge discharge pump. The system can also add coagulants (such as chemical phosphorus removal agents) into the water distribution system through the dosing system to improve the chemical phosphorus removal effect and activated sludge flocculation effect of the system, so that the secondary sedimentation tank can be used in the high-efficiency mud-water separation process. Medium-coupled chemical phosphorus removal, and further removal of SS and phosphate in the supernatant of the secondary sedimentation tank through the subsequent integrated depth filtration system (coupled filter tank).

After the coagulant is mixed with the sludge-water mixture of the biological system, it is helpful for the formation of the suspended activated sludge layer, which can not only improve the adsorption and flocculation effect of the suspended sludge layer in the secondary sedimentation tank, but also remove the phosphate in the water. The function of mud-water separation and chemical phosphorus removal is coupled to improve the operation efficiency of the secondary sedimentation tank.

The present invention has the following advantages and positive effects:

1. In the present invention, a stirring system is set inside the traditional secondary sedimentation tank, which can form a suspended activated sludge layer. Compared with the sedimentation mud-water separation effect of the traditional secondary sedimentation tank, the suspended activated sludge layer can be used for the biological system mixed liquid entering the secondary sedimentation tank. Net replenishment, adsorption, flocculation and finally through precipitation to achieve rapid mud-water separation effect.

2. The hydraulic retention time of the high-efficiency activated sludge retention type secondary sedimentation tank with the function of coupling depth filtration of the present invention is 1.5-2.5 h, which saves more than 30% of the tank capacity and land occupation compared with the traditional secondary sedimentation tank.

3. In the present invention, the coagulant (such as phosphorus removal agent) can be added into the water distribution system through the dosing system. After the coagulant is mixed with the mud-water mixture of the biological system, it is helpful for the formation of the suspended activated sludge layer. This not only improves the adsorption and flocculation effect of the suspended sludge layer in the secondary sedimentation tank, but also removes phosphate in the water, couples the functions of sludge water separation and chemical phosphorus removal, and improves the operational efficiency of the secondary sedimentation tank.

4. In the present invention, the coupled filter tank is arranged around the tank body and coupled to form an integrated depth filtration system, so that the effluent of the secondary sedimentation tank directly flows into the coupled filter tank by gravity, which not only saves the energy consumption of the secondary lifting, but also saves the corresponding sewage pipelines, etc.

Description of drawings

Figure 1 is a side view of the structure of a high-efficiency activated sludge retention type secondary sedimentation tank coupled with a depth filtration function;

Figure 2 is a top view of the structure of a high-efficiency activated sludge retention type secondary sedimentation tank coupled with a depth filtration function;

Figure 3 is a process flow diagram of a high-efficiency activated sludge retention type secondary sedimentation tank coupled with a depth filtration function.

In the figure: 1. Water inlet pipe; 2. Water distribution system; 3. Overflow weir; 4. Slag baffle; 5. Overflow port; 6. Slag scraper; 7. Mud scraper; 8. Drive motor; 9. Mixing system; 10. Coupling filter tank; 11. Water outlet; 12. Sludge discharge/sludge return port; 13. Tank body; 14. Water distribution system; 15. Dosing system; 16. High efficiency with coupled depth filtration Activated sludge retention type secondary sedimentation tank.

Detailed ways

As shown in Figures 1 and 2, a high-efficiency activated sludge retention type secondary sedimentation tank process system with coupled depth filtration function consists of a water distribution system, a dosing system and a high-efficiency activated sludge retention type secondary sedimentation tank with coupled depth filtration function. pool composition.

The high-efficiency activated sludge retention type secondary sedimentation tank with coupled depth filtration function includes a tank body 13, a water inlet pipe 1, a water distribution system 2, an overflow weir 3, a slag baffle 4, a slag scraper 6, and a mud scraper 7. , drive motor 8, stirring device 9 and coupling filter tank 10.

The water inlet pipe 1 is externally connected to a water distribution system 14 , and the water distribution system 2 surrounds the water inlet pipe 1 to guide the outlet of the water inlet pipe 1 and evenly distribute it into the pool body 13 .

The stirring device 9 is installed on the inner wall of the tank body 13, and through the control of the stirring power, a stable and efficient activated sludge layer is formed in the tank body 13, and the sludge layer is about 50-80% of the depth of the tank.

The overflow weir 3 has a zigzag structure, and is arranged in a ring shape at the water surface inside the tank body 13, which can ensure uniform water output.

The slag baffle plate 4 is a baffle plate that is half submerged under the water surface, and is arranged inside the overflow weir 3 to block the scum on the water surface.

The overflow port 5 is outside the overflow weir 3 , and the effluent flows into the overflow port 5 through the overflow weir 3 , and flows into the coupled filter tank 10 through the overflow port 5 .

The slag scraper 6 is submerged into the water and is connected to the drive motor 8 .

The scraper 7 is located at the bottom of the pool body 13 , is close to the bottom of the pool body 13 and is parallel, and is connected with the drive motor 8 at the same time.

The drive motor 8 drives the slag scraper 6 and the mud scraper 7 to perform a slow circular motion, the slag scraper 6 removes the scum on the water surface, and the mud scraper 7 scrapes the mud at the bottom of the pool to the mud discharge/sludge return port 12. Sludge and backflow are carried out.

The coupled filter tank 10 is arranged on the periphery of the tank body 13, and can be fully or partially surrounded after calculation according to the actual hydraulic load. The inside of the coupled filter tank (10) can use multi-layer sand filter or filter cloth and other filter materials. The load is low, and manual cleaning or automatic cleaning mode can be used. The effluent of the tank body flows into the coupled filter tank 10 through the overflow port 5, and flows out of the system through the water outlet 11 of the coupled filter tank 10 after being filtered.

As shown in Figure 3: the working process of the present invention is: the biological system mud-water mixture enters the water distribution system 14, enters the water inlet pipe 1 through the water distribution system 14, enters the pool body 13 through the water inlet pipe 1 and the water distribution system 2, and then enters the pool body 13. In 13, the suspended activated sludge layers with different high and low densities are formed by the stirring device 9. The activated sludge with high density enters the sludge hopper at the bottom of the secondary sedimentation tank through precipitation, and part of it is returned to the biological treatment system through the internal return pump. It is discharged out of the tank through the scraper at the bottom of the secondary sedimentation tank and the sludge discharge/sludge return port 12, and enters the subsequent sludge treatment system. The dosing system 15 can add coagulants (such as chemical phosphorus removal agents) into the water distribution system 14. After the coagulant is mixed with the biological system mud-water mixture, it helps to form a suspended activated sludge layer, which not only improves the The adsorption and flocculation effect of the secondary sedimentation tank suspends the sludge layer, and at the same time, it can remove the phosphate in the water, and the mud-water separation and chemical phosphorus removal functions are coupled to improve the operation efficiency of the secondary sedimentation tank.

Claims (3)

1. The utility model provides a high-efficient activated sludge retention type secondary sedimentation pond process systems with coupling depth filtering capability, includes water distribution system, its characterized in that: the water distribution system is communicated with an efficient activated sludge interception type secondary sedimentation tank with a coupling depth filtering function, the efficient activated sludge interception type secondary sedimentation tank with the coupling depth filtering function comprises a tank body, a water inlet pipe, a water distribution system, an overflow weir, a slag blocking plate, a slag scraping plate, a mud scraping plate, a driving motor, a stirring device and a coupling type filtering tank, the water inlet pipe is vertically arranged at the center of the tank body, the driving motor is arranged at the top of the water inlet pipe, the water distribution system surrounds the water inlet pipe, the stirring device is arranged on the inner wall of the tank body, the overflow weir is arranged on the water surface in the tank body, an overflow port is formed outside the overflow weir, the slag blocking plate is arranged inside the overflow weir, the slag scraping plate is arranged at the upper part of the water surface of the tank body, the slag scraping plate and the mud scraping plate are both connected with the driving motor, the coupling type filtering tank is arranged around the tank body and is communicated with the overflow port, the bottom of the tank body is provided with a water outlet, the bottom end of the tank body is provided with a sludge/sludge return port, and the water distribution system is communicated with a water inlet pipe.

2. The high efficiency activated sludge retention type secondary sedimentation tank process system with the coupled depth filtration function as claimed in claim 1, wherein: the water distribution system is externally connected with a dosing system.

3. The high efficiency activated sludge retention type secondary sedimentation tank process system with the coupled depth filtration function as claimed in claim 1, wherein: the overflow weir is of a zigzag structure and is annularly arranged on the water surface inside the pool body.

Images