Oxidation ditch activated sludge treatment system

Abstract

The utility model discloses an oxidation ditch activated sludge treatment system, which relates to the technical field of sewage treatment, and comprises a coarse screen and a fine screen, a communicating pipe is fixedly communicated between the coarse screen and the fine screen, a lift pump is fixedly arranged in the middle of the communicating pipe, the water outlet end of the fine screen is communicated with a rotational flow grit chamber, and the water outlet end of the fine screen is communicated with the rotational flow grit chamber. The water outlet end of the rotational flow grit chamber is communicated with a pre-anoxic tank, the water outlet end of the pre-anoxic tank is communicated with an anoxic tank, the water outlet end of the anoxic tank is connected with an oxidation ditch, the other part of effluent of the oxidation ditch enters a secondary sedimentation tank through a water outlet pipe, and mud-water separation is realized in the secondary sedimentation tank through gravity sedimentation; a part of sludge in the secondary sedimentation tank flows back into the anoxic tank through the sludge return pipe, so that microorganisms in the part of sludge are fully utilized, the microbial biomass of a biochemical system can be greatly increased, and the degradation efficiency of unit tank capacity of the biochemical tank on various pollutants is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of sewage treatment, in particular to an oxidation ditch activated sludge treatment system. Background Art

[0002] The oxidation ditch is also known as the circulating baffled oxidation ditch. It uses aerators for aeration. Currently, the oxidation ditch is widely used in many sewage treatment plants to treat sewage.

[0003] However, in the prior art, the amount of microorganisms in the biochemical system of the existing oxidation ditch is relatively limited, and the degradation efficiency of various pollutants in sewage is low, making it difficult for the effluent quality of the oxidation ditch to meet the standards, and the energy consumption is high, resulting in high operating costs for the oxidation ditch. Utility Model Content

[0004] The purpose of the utility model is to solve the problems in the prior art that the amount of microorganisms in the biochemical system of the existing oxidation ditch is relatively limited, the degradation efficiency of various pollutants in sewage is low, the effluent quality of the oxidation ditch is difficult to meet the standards, and the energy consumption is high, thus leading to high operating costs of the oxidation ditch, and an oxidation ditch activated sludge treatment system is proposed.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: an oxidation ditch activated sludge treatment system, comprising a coarse grid and a fine grid, a connecting pipe is fixedly connected between the coarse grid and the fine grid, a lifting pump is fixedly installed in the middle of the connecting pipe, the water outlet end of the fine grid is connected to a vortex grit settling tank, the water outlet end of the vortex grit settling tank is connected to a pre-anoxic tank, the water outlet end of the pre-anoxic tank is connected to an anoxic tank, the water outlet end of the anoxic tank is connected to an oxidation ditch, the tail end of the oxidation ditch is fixedly connected to a second return pipe, one end of the second return pipe The end is fixedly connected with the anoxic tank, the tail end of the oxidation ditch is fixedly connected with an outlet pipe, one end of the outlet pipe is fixedly connected with a secondary sedimentation tank, the outlet end of the secondary sedimentation tank is fixedly connected with a filtration and disinfection tank, the bottom of the secondary sedimentation tank is fixedly connected with a sludge return pipe, one end of the sludge return pipe is fixedly connected with the anoxic tank, the bottom of the secondary sedimentation tank is fixedly connected with a sludge discharge pipe, one end of the sludge discharge pipe is fixedly connected with a sludge thickening tank, and a first return pipe is fixedly connected between the outlet end of the sludge thickening tank and the water inlet end of the lift pump.

[0006] Preferably, a vertical-axis impeller aerator is installed on the inner wall of one end of the oxidation ditch, and a first flow promoter is provided on one side of the vertical-axis impeller aerator.

[0007] Preferably, a second flow producer is provided on the other side of the vertical-axis impeller aerator, and the first flow producer and the second flow producer are both installed on the inner wall of the oxidation ditch.

[0008] Preferably, a transverse axis rotating brush aerator is provided on one side of the second flow promoter, and the transverse axis rotating brush aerator is installed on the inner wall of the oxidation ditch.

[0009] Preferably, a re-filtration pool is provided inside the filtration and disinfection pool, and a disinfection pool is provided on one side of the re-filtration pool.

[0010] Preferably, a partition is fixedly connected between the re-filtration tank and the disinfection tank.

[0011] Preferably, a filter plate is fixedly connected to the inner wall of the re-filtration tank.

[0012] Compared with the prior art, the advantages and positive effects of the utility model are:

[0013] 1. In the utility model, a part of the effluent is returned to the front end of the anoxic tank through the second return pipe at the tail end of the oxidation ditch, and the return ratio is set to a volume ratio of the return water volume to the influent to be treated of 1:1 according to the denitrification requirement; finally, another part of the effluent from the oxidation ditch enters the secondary sedimentation tank through the outlet pipe, and the mud and water are separated by gravity sedimentation in the secondary sedimentation tank; a part of the sludge in the secondary sedimentation tank is returned to the anoxic tank through the sludge return pipe, so that the microorganisms in part of the sludge are fully utilized, which can greatly increase the amount of microorganisms in the biochemical system and improve the degradation efficiency of various pollutants per unit tank capacity of the biochemical tank.

[0014] 2. In the present invention, by setting the first flowmaker, the vertical-axis impeller aerator, the second flowmaker and the horizontal-axis rotary brush aerator, the MBBR filler in the oxidation ditch is in a fluidized state by the lifting effect of aeration and water flow, thereby reducing energy consumption and further improving the economic benefits of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The utility model provides a structural schematic diagram of an oxidation ditch activated sludge treatment system;

[0016] Figure 2 This is a schematic diagram of the structure of the filtration and disinfection tank of the oxidation ditch activated sludge treatment system proposed in the utility model;

[0017] Figure 3 The utility model provides an oxidation ditch structure schematic diagram of an oxidation ditch activated sludge treatment system.

[0018] Legend: 1. Coarse screen; 2. Fine screen; 3. Lifting pump; 4. Cyclone sand settling tank; 5. Pre-anoxic tank; 6. Anoxic tank; 7. Oxidation ditch; 701. First flow pusher; 702. Vertical axis impeller aerator; 703. Second flow pusher; 704. Horizontal axis rotary brush aerator; 8. Secondary sedimentation tank; 9. Filtration and disinfection tank; 901. Refiltration tank; 902. Disinfection tank; 903. Filter plate; 904. Partition; 10. Sludge thickening tank; 11. Connecting pipe; 12. First return pipe; 13. Second return pipe; 14. Outlet pipe; 15. Sludge return pipe; 16. Sludge discharge pipe. DETAILED DESCRIPTION

[0019] In order to more clearly understand the above-mentioned purpose, features and advantages of the utility model, the utility model is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0020] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure. Embodiment 1

[0021] like Figure 1-3 As shown, the utility model provides an oxidation ditch activated sludge treatment system, including a coarse grid 1 and a fine grid 2, a connecting pipe 11 is fixedly connected between the coarse grid 1 and the fine grid 2, a lifting pump 3 is fixedly installed in the middle of the connecting pipe 11, the water outlet end of the fine grid 2 is connected to a cyclone sand settling tank 4, the water outlet end of the cyclone sand settling tank 4 is connected to a pre-anoxic tank 5, the water outlet end of the pre-anoxic tank 5 is connected to an anoxic tank 6, the water outlet end of the anoxic tank 6 is connected to an oxidation ditch 7, the tail end of the oxidation ditch 7 is fixedly connected to a second return pipe 13, one end of the second return pipe 13 is fixedly connected to the anoxic tank 6 The tail end of the oxidation ditch 7 is fixedly connected with an outlet pipe 14, one end of the outlet pipe 14 is fixedly connected with a secondary sedimentation tank 8, the outlet end of the secondary sedimentation tank 8 is fixedly connected with a filtration and disinfection tank 9, the bottom of the secondary sedimentation tank 8 is fixedly connected with a sludge return pipe 15, one end of the sludge return pipe 15 is fixedly connected with the anoxic tank 6, the bottom of the secondary sedimentation tank 8 is fixedly connected with a sludge discharge pipe 16, one end of the sludge discharge pipe 16 is fixedly connected with a sludge thickening tank 10, and a first reflux pipe 12 is fixedly connected between the outlet end of the sludge thickening tank 10 and the water inlet end of the lifting pump 3.

[0022] The specific configuration and function of the present embodiment are described in detail below. A portion of the effluent is returned to the front end of the anoxic tank 6 through the second return pipe 13 at the tail end of the oxidation ditch 7. The return ratio is set to a 1:1 ratio of the volume of the return water to the volume of the influent to be treated according to the denitrification requirement. Finally, another portion of the effluent from the oxidation ditch 7 enters the secondary sedimentation tank 8 through the outlet pipe 14, and mud and water are separated by gravity sedimentation in the secondary sedimentation tank 8. A portion of the sludge in the secondary sedimentation tank 8 is returned to the anoxic tank 6 through the sludge return pipe 15, so that the microorganisms in part of the sludge are fully utilized, which can greatly increase the amount of microorganisms in the biochemical system and improve the degradation efficiency of various pollutants per unit tank capacity of the biochemical tank. Embodiment 2

[0023] like Figure 1-3 As shown, a vertical-axis impeller aerator 702 is installed on the inner wall of one end of the oxidation ditch 7, a first flow producer 701 is arranged on one side of the vertical-axis impeller aerator 702, a second flow producer 703 is arranged on the other side of the vertical-axis impeller aerator 702, the first flow producer 701 and the second flow producer 703 are both installed on the inner wall of the oxidation ditch 7, a horizontal-axis rotating brush aerator 704 is arranged on one side of the second flow producer 703, and the horizontal-axis rotating brush aerator 704 is installed on the inner wall of the oxidation ditch 7, a re-filtration tank 901 is arranged inside the filtration and disinfection tank 9, a disinfection tank 902 is arranged on one side of the re-filtration tank 901, a partition 904 is fixedly connected between the re-filtration tank 901 and the disinfection tank 902, and a filter plate 903 is fixedly connected to the inner wall of the re-filtration tank 901.

[0024] The effect achieved by the entire embodiment is that, through the arrangement of the first flow producer 701, the vertical axis impeller aerator 702, the second flow producer 703 and the horizontal axis rotary brush aerator 704, the MBBR filler in the oxidation ditch 7 is in a fluidized state by relying on the lifting effect of aeration and water flow, thereby reducing energy consumption and further improving the economic benefits of the utility model. By allowing the effluent from the secondary sedimentation tank 8 to enter the filtration and disinfection tank 9 and then undergoing filtration and disinfection measures, the tail water meets the discharge standards and can be reused.

[0025] The use method and working principle of this device are as follows: the sewage enters the coarse screen 1 to remove large-sized floating objects, suspended matter and smaller solid substances; the sewage is lifted to the fine screen 2 for subsequent treatment by the lifting pump 3; the inorganic particles with higher density are removed by the cyclone sand settling tank 4; then the sewage enters the pre-anoxic tank 5, and the COD and SS pollutants in the incoming water are degraded by the metabolism of the anoxic microorganisms in the pre-anoxic tank 5. At the same time, the incoming water is mixed with the return water from the oxidation ditch 7 and then undergoes a denitrification reaction in the anoxic tank 6, thereby reducing the total nitrogen index. The water treated in the anoxic tank 6 enters the oxidation ditch 7, and the COD, ammonia nitrogen, total nitrogen, chromaticity and SS pollutants in the incoming water are degraded by the metabolism of the aerobic microorganisms therein. At the tail end of the oxidation ditch 7, the effluent is discharged through the second reflux pipe 13. A part of it is returned to the front end of the anoxic tank 6, and the return ratio is set to a volume ratio of 1:1 between the volume of the return water and the volume of the influent to be treated according to the denitrification needs; finally, another part of the effluent from the oxidation ditch 7 enters the secondary sedimentation tank 8 through the outlet pipe 14, and the mud and water are separated by gravity sedimentation in the secondary sedimentation tank 8; the effluent from the secondary sedimentation tank 8 enters the filtration and disinfection tank 9 and then, after filtration and disinfection measures, the tail water meets the discharge standards and is reused: a part of the sludge in the secondary sedimentation tank 8 is returned to the anoxic tank 6 through the sludge return pipe 15, and the remaining sludge enters the sludge thickening tank 10 through the sludge discharge pipe 16. The sludge in the sludge thickening tank 10 produces a mud cake after dehydration, and the supernatant and the filtered water in the sludge thickening tank 10 are returned to the second return pipe 13 through the first return pipe 12 to participate in the re-circulation treatment.

[0026] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. Oxidation ditch activated sludge treatment system, characterized by: The invention comprises a coarse screen (1) and a fine screen (2), wherein a connecting pipe (11) is fixedly connected between the coarse screen (1) and the fine screen (2), a lifting pump (3) is fixedly installed in the middle of the connecting pipe (11), a water outlet end of the fine screen (2) is connected to a cyclone grit chamber (4), a water outlet end of the cyclone grit chamber (4) is connected to a pre-anoxic tank (5), a water outlet end of the pre-anoxic tank (5) is connected to an anoxic tank (6), an water outlet end of the anoxic tank (6) is connected to an oxidation ditch (7), a tail end of the oxidation ditch (7) is fixedly connected to a second return pipe (13), one end of the second return pipe (13) is fixedly connected to the anoxic tank (6), and the oxidation ditch (7) is connected to a second return pipe (13). ) is fixedly connected to a water outlet pipe (14), one end of the water outlet pipe (14) is fixedly connected to a secondary sedimentation tank (8), the water outlet end of the secondary sedimentation tank (8) is fixedly connected to a filtering and disinfection tank (9), the bottom of the secondary sedimentation tank (8) is fixedly connected to a sludge return pipe (15), one end of the sludge return pipe (15) is fixedly connected to the anoxic tank (6), the bottom of the secondary sedimentation tank (8) is fixedly connected to a sludge discharge pipe (16), one end of the sludge discharge pipe (16) is fixedly connected to a sludge thickening tank (10), and a first return pipe (12) is fixedly connected between the water outlet end of the sludge thickening tank (10) and the water inlet end of the lifting pump (3).

2. The oxidation ditch activated sludge treatment system according to claim 1, characterized in that: A vertical shaft impeller aerator (702) is installed on the inner wall of one end of the oxidation ditch (7), and a first flow promoter (701) is arranged on one side of the vertical shaft impeller aerator (702).

3. The oxidation ditch activated sludge treatment system according to claim 2, characterized in that: A second flow maker (703) is provided on the other side of the vertical shaft impeller aerator (702), and the first flow maker (701) and the second flow maker (703) are both installed on the inner wall of the oxidation ditch (7).

4. The oxidation ditch activated sludge treatment system according to claim 3, characterized in that: A horizontal axis rotating brush aerator (704) is provided on one side of the second flow promoter (703), and the horizontal axis rotating brush aerator (704) is installed on the inner wall of the oxidation ditch (7).

5. The oxidation ditch activated sludge treatment system according to claim 1, characterized in that: A re-filtration pool (901) is provided inside the filtration and disinfection pool (9), and a disinfection pool (902) is provided on one side of the re-filtration pool (901).

6. The oxidation ditch activated sludge treatment system according to claim 5, characterized in that: A partition (904) is fixedly connected between the re-filtration tank (901) and the disinfection tank (902).

7. The oxidation ditch activated sludge treatment system according to claim 6, characterized in that: A filter plate (903) is fixedly connected to the inner wall of the re-filtration tank (901).

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