Special sedimentation tank for advanced nitrogen and phosphorus removal AOA process for sewage treatment

Abstract

The utility model relates to the technical field of sewage treatment, in particular to a sedimentation tank special for a sewage treatment advanced nitrogen and phosphorus removal AOA process. The sewage treatment device comprises a tank body, a multifunctional water inlet tank and a sludge scraper, the multifunctional water inlet tank is arranged at a water inlet of the tank body and communicated with the inside of the tank body, the sludge scraper is mounted in the tank body, the tank body is provided with a sludge storage hopper, and a sludge compression area, a horizontal flow sedimentation area and an inclined plate sedimentation area which are communicated are sequentially arranged in the tank body in the water flow direction. The sludge scraper extends into the horizontal flow sedimentation area and the inclined plate sedimentation area, the sludge storage hopper is located in the sludge compression area, the sludge scraper scrapes sludge in the inclined plate sedimentation area and the horizontal flow sedimentation area into the sludge storage hopper, and the sludge storage hopper is of a large-capacity groove body structure extending downwards from the bottom of the tank body. The volume of the sludge storage hopper is increased, the sludge concentration of returned sludge can be improved, and the sludge reflux ratio is reduced; the multifunctional water inlet tank is arranged at the front end of the original sedimentation tank body, so that the sedimentation effect of the secondary sedimentation tank is enhanced, and the SS value of effluent is reduced.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, and in particular to a sedimentation tank specifically designed for the deep denitrification and phosphorus removal (AOA) process in wastewater treatment. Background Technology

[0002] AOA (Anaerobic-Oxygen-Oriented) wastewater treatment is a modified biological nitrogen and phosphorus removal process. Through the synergistic effects of anaerobic, anoxic, and aerobic environmental conditions and microbial communities, it achieves the removal of organic matter, nitrification and denitrification of nitrogen, and the release and absorption of phosphorus. It effectively removes pollutants such as carbon, nitrogen, and phosphorus from wastewater, resulting in effluent that meets high standards. AOA wastewater treatment is widely used in municipal wastewater treatment plants and various industrial wastewater treatment fields, such as food processing wastewater, pharmaceutical wastewater, and dyeing wastewater. Especially in regions and industries with strict requirements for nitrogen and phosphorus emissions, the AOA process has been widely applied and promoted due to its highly efficient nitrogen and phosphorus removal effects.

[0003] In the AOA wastewater treatment process, the main function of the sedimentation tank is to achieve solid-liquid separation, clarify the treated water, and collect and discharge the settled sludge. Existing sedimentation tanks lack dedicated sludge storage hoppers, or some contain small-sized hoppers that are poorly matched to the AOA process. This results in insufficient sludge settling and compression, leading to high water content in the pumped sludge and reduced sludge pumping efficiency. Utility Model Content

[0004] This utility model provides a sedimentation tank specifically designed for the deep denitrification and phosphorus removal (AOA) process in wastewater treatment, aiming to solve problems such as the lack of sludge storage hoppers or the sludge storage hoppers being too small in existing sedimentation tanks, which prevents the sludge from being fully settled and compressed.

[0005] This utility model provides a sedimentation tank specifically designed for deep nitrogen and phosphorus removal (AOA) processes in wastewater treatment. The tank includes a tank body, a multi-functional inlet trough, and a sludge scraper. The multi-functional inlet trough is located at the inlet of the tank body and communicates with the interior of the tank body. The sludge scraper is installed inside the tank body. The tank body is equipped with a sludge storage hopper. Inside the tank body, along the water flow direction, there are interconnected sludge compression zones, horizontal sedimentation zones, and inclined plate sedimentation zones. The sludge scraper extends into the horizontal sedimentation zones and the inclined plate sedimentation zones. The sludge storage hopper is located in the sludge compression zone. The sludge scraper scrapes sludge from the inclined plate sedimentation zones and the horizontal sedimentation zones into the sludge storage hopper. The sludge storage hopper is a large-capacity trough structure extending downwards from the bottom of the tank body.

[0006] As a further improvement of this utility model, the depth of the sludge storage hopper extending downward from the bottom of the pool is greater than 2mm.

[0007] As a further improvement of this utility model, the sludge retention time in the sludge storage hopper is greater than 5 minutes.

[0008] As a further improvement of this utility model, the connection port between the multifunctional water inlet trough and the pool body is located above the sludge storage hopper, and the connection port between the multifunctional water inlet trough and the pool body is provided with a finger-slit rectifier wall.

[0009] As a further improvement of this utility model, the sedimentation tank for the deep denitrification and phosphorus removal AOA process in wastewater treatment also includes aeration equipment, which includes an aerator, a perforated aeration pipe, and a main air outlet pipe. The perforated aeration pipe is installed in the multi-functional inlet tank and is connected to the aerator through the main air outlet pipe.

[0010] As a further improvement of this utility model, the sedimentation tank for the deep denitrification and phosphorus removal AOA process in wastewater treatment also includes a dosing device, which includes a storage tank, a dosing pump, and a dosing pipe. The storage tank is connected to the inlet of the dosing pump through the dosing pipe, and the outlet of the dosing pump is connected to the multi-functional inlet tank through the dosing pipe.

[0011] As a further improvement of this utility model, the sedimentation tank for the deep denitrification and phosphorus removal AOA process in wastewater treatment also includes a sludge return pump, the inlet of which is connected to a sludge storage hopper.

[0012] As a further improvement of this utility model, the sludge scraper includes a sludge scraping chain, sludge scraping plates, and a sludge scraping drive motor. A plurality of sludge scraping plates are evenly distributed on the sludge scraping chain. The sludge scraping chain extends into the horizontal sedimentation zone and the inclined plate sedimentation zone. The sludge scraping drive motor is connected to and drives the sludge scraping chain.

[0013] As a further improvement of this utility model, the sedimentation tank for the deep denitrification and phosphorus removal AOA process in wastewater treatment also includes a clear water filtration component. The clear water filtration component is installed in the tank body and located above the inclined plate sedimentation zone. The clear water filtration component is connected to the outlet of the tank body.

[0014] As a further improvement of this utility model, the water filtration assembly includes a skimmer, a mudguard, an inclined plate, and a triangular weir. The skimmer, mudguard, and triangular weir are arranged sequentially above the sedimentation area of ​​the inclined plate along the water flow direction, and the inclined plate is installed below the triangular weir.

[0015] The beneficial effects of this utility model are as follows: After optimizing the tank shape, the volume of the sludge storage hopper is increased, which can improve the sludge concentration of the returned sludge, reduce the sludge return ratio, and thus reduce the energy consumption of the sludge return system; and a multi-functional inlet tank is set at the front end of the sedimentation tank, which enhances the sedimentation effect of the sedimentation tank through the synergistic effect of chemical dosing and air flotation, reduces the SS value of the effluent, and has the effect of simultaneous phosphorus removal. The aeration rate and chemical dosage of the multi-functional inlet tank can be adjusted according to different water qualities to ensure the effluent quality of the sedimentation tank. Attached Figure Description

[0016] Figure 1 This is a structural diagram of a sedimentation tank specifically designed for the AOA (Anaerobic Oxygenation and Phosphorus Removal) process in wastewater treatment according to this utility model.

[0017] Figure 2 This is another structural diagram of the sedimentation tank for the AOA process of deep denitrification and phosphorus removal in wastewater treatment in this utility model. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0019] like Figures 1 to 2 As shown, this utility model discloses a sedimentation tank for a deep denitrification and phosphorus removal (AOA) process in wastewater treatment. It includes a tank body 1, a multi-functional inlet tank 2, and a sludge scraper 3. The multi-functional inlet tank 2 is located at the inlet of the tank body 1 and communicates with the interior of the tank body 1. The sludge scraper 3 is installed inside the tank body 1. The tank body 1 is equipped with a sludge storage hopper 4. Inside the tank body 1, along the water flow direction, there are interconnected sludge compression zones 11, horizontal sedimentation zones 12, and inclined plate sedimentation zones 13. The sludge scraper 3 extends into the horizontal sedimentation zones 12 and 13. The sludge storage hopper 4 is located in the sludge compression zone 11. The sludge scraper 3 scrapes the sludge from the inclined plate sedimentation zone 13 and the horizontal sedimentation zone 12 into the sludge storage hopper 4. The sludge storage hopper 4 is a large-capacity tank structure extending downwards from the bottom of the tank body 1.

[0020] The horizontal sedimentation zone 12 of the tank body 1 is used to collect sludge that naturally settles down during the flow of sewage. The inclined plate 83 sedimentation zone 13 is used to collect sludge that is intercepted and settled by the clear water filter component 8 during the clear water filtration process. The sludge scraper 3 is located at the bottom of the tank body 1 and moves from the inclined plate 83 sedimentation zone 13 and the horizontal sedimentation zone 12 towards the sludge compression zone 11. The sludge settled in the inclined plate 83 sedimentation zone 13 and the horizontal sedimentation zone 12 is collected into the sludge storage hopper 4. The sludge storage hopper 4 adopts a larger groove shape and is lower than the bottom of the tank body 1. This structure can store more sludge more centrally and also gives the sludge a longer sedimentation and compression space. After the sludge is concentrated, the solids content is increased by more than 3 times compared with the traditional sedimentation tank. When used as a sedimentation tank in the AOA process, it can significantly reduce the sludge return ratio and reduce the energy consumption of the sludge return pump 7 by more than 70%. A multi-functional inlet tank 2 is installed at the front end of the sedimentation tank 1. Through the synergistic effect of chemical dosing and air flotation, the sedimentation effect of the sedimentation tank is enhanced, the SS value of the effluent is reduced, and it also has the effect of simultaneous phosphorus removal. The aeration rate and chemical dosage of the multi-functional inlet tank 2 can be adjusted according to different water qualities to ensure the effluent quality of the sedimentation tank.

[0021] The sludge hopper 4 extends downwards from the bottom of the tank 1 to a depth greater than 2 mm. The sludge retention time in the sludge hopper 4 is greater than 5 minutes. The height of the sludge hopper 4 in this sedimentation tank needs to be greater than 2 m, and the calculated retention time in the sludge hopper 4 needs to be greater than 5 minutes. The optimized sludge hopper 4 has a volume more than twice that of the traditional sludge inlet, increasing the concentration of returned sludge by more than 50%, making it more suitable for the AOA process, significantly increasing the concentration of returned sludge, greatly reducing the sludge return ratio, and thus reducing the operating energy consumption of the sludge return pump 7.

[0022] The connection between the multi-functional inlet trough 2 and the tank body 1 is located above the sludge storage hopper 4, and a finger-slit rectifier wall 21 is provided at the connection. This design, with the connection above the sludge storage hopper 4, allows the water flow from the multi-functional inlet trough 2 to be staggered with the sludge storage hopper 4, preventing the water flow from impacting the sludge in the hopper 4 and affecting the sedimentation and compression effect. Simultaneously, some of the sludge in the wastewater discharged from the multi-functional inlet trough 2 will also settle into the sludge storage hopper 4. The finger-slit rectifier wall 21 makes the water flow at the outlet of the multi-functional inlet trough 2 more uniform and stable.

[0023] The sedimentation tank for the deep denitrification and phosphorus removal (AOA) process in wastewater treatment also includes an aeration device 5. The aeration device 5 includes an aerator 51, perforated aeration pipes 52, and a main air outlet pipe 53. The perforated aeration pipes 52 are installed inside the multi-functional inlet tank 2 and are connected to the aerator 51 via the main air outlet pipe 53. The aerator 51 can be an air compressor or a blower. At least one aeration device 5 is provided in the multi-functional inlet tank 2. The aeration device 5 can blow away small nitrogen bubbles attached to the AOA effluent sludge, inhibiting the denitrification process and slowing down sludge floating. The aeration device 5 in the multi-functional inlet tank 2 uses perforated aeration pipes 52 within the tank body 1. The perforated aeration pipes 52, ranging from DN40 to DN200, are adapted according to the influent flow rate, and single or multiple rows of perforated aeration pipes 52 are selected based on the corresponding aeration volume.

[0024] The sedimentation tank for the advanced nitrogen and phosphorus removal (AOA) process in wastewater treatment also includes a dosing device 6. The dosing device 6 comprises a storage tank 61, a dosing pump 62, and a dosing pipe 63. The storage tank 61 is connected to the inlet of the dosing pump 62 via the dosing pipe 63, and the outlet of the dosing pump 62 is connected to the multi-functional inlet tank 2 via the dosing pipe 63. At least one dosing device 6 is installed in the multi-functional inlet tank 2. By adding appropriate chemicals into the multi-functional inlet tank 2 through the dosing device, chemical phosphorus removal can be achieved while simultaneously enhancing sludge settling performance and improving effluent quality.

[0025] The sedimentation tank for the advanced nitrogen and phosphorus removal (AOA) process in wastewater treatment also includes a sludge return pump 7, the inlet of which is connected to a sludge storage hopper 4. The sludge return pump 7 is used to pump the sludge that has been settled and compressed in the sludge storage hopper 4 to the next process. After prolonged compression, the sludge in the sludge storage hopper 4 has a significantly reduced water content. When pumped away by the sludge return pump 7, the sludge content per unit volume is greater, thus improving operational efficiency.

[0026] The sludge scraper 3 includes a scraper chain 31, scraper blades 32, and a scraper drive motor 33. Multiple scraper blades 32 are evenly distributed on the scraper chain 31, which extends into the horizontal sedimentation zone 12 and the inclined plate 83 sedimentation zone 13. The scraper drive motor 33 connects to and drives the scraper chain 31. The scraper drive motor 33 drives the scraper chain 31 to move within the tank 1, and pushes the sludge at the bottom of the inclined plate 83 sedimentation zone 13 and the horizontal sedimentation zone 12 into the sludge storage hopper 4 through the scraper blades 32, thus achieving centralized collection and sedimentation of the sludge.

[0027] The sedimentation tank for the deep denitrification and phosphorus removal (AOA) process in wastewater treatment also includes a clear water filtration assembly 8. The clear water filtration assembly 8 is located inside the tank body 1 and above the sedimentation zone 13 of the inclined plate 83. The clear water filtration assembly 8 connects to the outlet 14 of the tank body 1. The clear water filtration assembly 8 includes a skimmer 81, a baffle plate 82, an inclined plate 83, and a triangular weir 84. The skimmer 81, baffle plate 82, and triangular weir 84 are sequentially arranged above the sedimentation zone 13 of the inclined plate 83 along the water flow direction, with the inclined plate 83 installed below the triangular weir 84. The skimmer 81 is used to block impurities in the wastewater outside the triangular weir 84, and the baffle plate 82 is used to block floating sludge outside the triangular weir 84. After preliminary filtration by the skimmer 81 and baffle plate 82, the wastewater settles the remaining sludge in the area of ​​the inclined plate 83, forming a supernatant at the triangular weir 84. This supernatant is discharged through the outlet 14 for use in the next process.

[0028] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. A special sedimentation tank for advanced nitrogen and phosphorus removal AOA process of sewage treatment, characterized in that, The system includes a tank body, a multi-functional inlet tank, and a sludge scraper. The multi-functional inlet tank is located at the inlet of the tank body and communicates with the interior of the tank body. The sludge scraper is installed inside the tank body. The tank body is equipped with a sludge storage hopper. Inside the tank body, along the water flow direction, there are interconnected sludge compression zones, horizontal sedimentation zones, and inclined plate sedimentation zones. The sludge scraper extends into the horizontal sedimentation zones and the inclined plate sedimentation zones. The sludge storage hopper is located in the sludge compression zone. The sludge scraper scrapes the sludge from the inclined plate sedimentation zones and the horizontal sedimentation zones into the sludge storage hopper. The sludge storage hopper is a large-capacity trough structure that extends downward from the bottom of the tank body.

2. The special sedimentation tank for advanced nitrogen and phosphorus removal AOA process of sewage treatment according to claim 1, characterized in that, The sludge hopper extends downward from the bottom of the pool to a depth greater than 2 mm.

3. The special sedimentation tank for advanced nitrogen and phosphorus removal AOA process of sewage treatment according to claim 1, characterized in that, The sludge retention time in the sludge storage hopper is greater than 5 minutes.

4. The special sedimentation tank for advanced nitrogen and phosphorus removal AOA process of sewage treatment according to claim 1, characterized in that, The connection between the multifunctional water inlet trough and the pool body is located above the sludge storage hopper, and the connection between the multifunctional water inlet trough and the pool body is provided with a finger-slit rectifier wall.

5. The special sedimentation tank for advanced nitrogen and phosphorus removal AOA process of sewage treatment according to claim 1, characterized in that, It also includes aeration equipment, which includes an aerator, a perforated aeration pipe, and a main air outlet pipe. The perforated aeration pipe is installed in the multi-functional water inlet tank and is connected to the aerator through the main air outlet pipe.

6. The special sedimentation tank for advanced nitrogen and phosphorus removal AOA process of sewage treatment according to claim 1, characterized in that, It also includes a dosing device, which includes a storage tank, a dosing pump, and a dosing pipe. The storage tank is connected to the inlet of the dosing pump through the dosing pipe, and the outlet of the dosing pump is connected to a multi-functional water inlet tank through the dosing pipe.

7. The special sedimentation tank for advanced nitrogen and phosphorus removal AOA process of sewage treatment according to claim 1, characterized in that, It also includes a sludge return pump, the inlet of which is connected to a sludge storage hopper.

8. The sedimentation tank for the deep nitrogen and phosphorus removal (AOA) process in wastewater treatment according to claim 1, characterized in that, The sludge scraper includes a sludge scraping chain, sludge scraping blades, and a sludge scraping drive motor. Multiple sludge scraping blades are evenly distributed on the sludge scraping chain, which extends into the horizontal sedimentation zone and the inclined plate sedimentation zone. The sludge scraping drive motor is connected to and drives the sludge scraping chain.

9. The special sedimentation tank for advanced nitrogen and phosphorus removal AOA process of sewage treatment according to claim 1, characterized in that, It also includes a clear water filtration component, which is installed in the pool body and located above the inclined plate sedimentation area, and the clear water filtration component is connected to the water outlet of the pool body.

10. The special sedimentation tank for advanced nitrogen and phosphorus removal AOA process of sewage treatment according to claim 9, characterized in that, The water filtration assembly includes a skimmer, a mudguard, an inclined plate, and a triangular weir. The skimmer, mudguard, and triangular weir are arranged sequentially above the sedimentation zone of the inclined plate along the water flow direction, and the inclined plate is installed below the triangular weir.

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