Reflux device, biochemical reaction tank and sewage treatment system

Abstract

The present invention discloses a reflux device, a biochemical reaction tank and a sewage treatment system. The reflux device includes: a reflux pipe, a reflux bucket and a regulating cylinder. The present invention designs the reflux device to include a reflux pipe, a reflux bucket and a regulating cylinder. The reflux pipe is vertically installed in the biochemical reaction tank, the reflux bucket is installed at the upper end of the reflux pipe, and the regulating cylinder and the reflux bucket are adapted to adjust the flow rate of the liquid flowing from the reflux bucket into the reflux pipe, so as to facilitate the regulation of the reflux amount. On the other hand, the aerator stand is installed on the reflux pipe and is at a preset distance from the lower end of the reflux pipe. The aerator can be installed on the aerator stand. By installing the aerator stand on the reflux pipe, the functional division of the aerobic biochemical reaction zone above the aerator stand and the anaerobic and anoxic biochemical reaction zone below the aerator stand can be realized, thereby conveniently realizing the vertical flow anoxic aerobic activated sludge method sewage treatment process.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of sewage treatment, and in particular to a reflux device, a biochemical reaction tank and a sewage treatment system. Background Art

[0002] In the vertical flow anoxic aerobic activated sludge wastewater treatment process, i.e. the vertical zoned anoxic aerobic activated sludge wastewater treatment process, in order to transfer the nitrification liquid from the upper aerobic zone to the bottom anoxic zone, a nitrification liquid reflux pipe needs to be set up. When air lift reflux is used, a reflux bucket is also required to collect the nitrification liquid.

[0003] However, in existing large-scale sewage treatment facilities, such nitrification liquid return pipes are usually installed inside the reaction tank and submerged underwater, making it difficult to regulate the return volume. In addition, due to the need for vertical zoning of aerobic and anoxic, the aerobic aerator cannot be directly installed at the bottom of the reaction tank, but must be installed at a certain height above the bottom of the reaction tank to ensure that the lower area is anoxic or anaerobic. This requires a stand for fixing the aerator, and the stand must be fixed at a certain height above the bottom of the reaction tank, which increases the process difficulty of installing the aerator stand. Summary of the invention

[0004] The main technical problem solved by the embodiments of the present invention is to provide a reflux device, a biochemical reaction tank and a sewage treatment system for conveniently adjusting the reflux volume for a vertical flow anoxic aerobic activated sludge sewage treatment process.

[0005] In order to solve the above technical problems, a technical solution created by the present invention is to provide a reflux device, comprising:

[0006] A reflux pipe, which is a vertically mounted hollow pipe, and a plurality of reflux holes are arranged on the pipe wall at the lower end of the reflux pipe, and an aerator stand is arranged at a position of the reflux pipe at a preset distance from the lower end;

[0007] A reflux hopper, the reflux hopper comprising a first opening and a second opening, the cross section of the first opening is larger than the cross section of the second opening, and the second opening is connected to the upper end of the reflux pipe;

[0008] The regulating cylinder is arranged in the reflux bucket and matched with the second opening, and the regulating cylinder is used to adjust the flow rate of the liquid flowing from the reflux bucket into the reflux pipe.

[0009] Optionally, the reflux funnel comprises a first straight cylinder, a reducer and a second straight cylinder connected in sequence, one end of the reducer gradually tapers toward the other end, one end of the first straight cylinder is provided with the first opening, the other end of the first straight cylinder is connected to one end of the reducer, the other end of the reducer is connected to one end of the second straight cylinder, and the second straight cylinder is provided with the second opening at one end away from the reducer.

[0010] Optionally, the adjusting cylinder is a hollow tube with one end sealed, a plurality of through holes are arranged on the side wall of the adjusting cylinder, the other end of the adjusting cylinder is inserted into the second straight cylinder, and the relative position between the adjusting cylinder and the second straight cylinder is adjustable.

[0011] Optionally, the reflux device further comprises:

[0012] The assembly flange includes a first flange and a second flange detachably connected to the first flange, the first flange is arranged at one end of the reflux hopper close to the second opening, and the second flange is arranged at the upper end of the reflux pipe.

[0013] In order to solve the above technical problems, the present application also provides a biochemical reaction tank, including an aerator and a reflux device as described above, wherein the lower end of the reflux pipe is installed at the bottom of the biochemical reaction tank, the reflux bucket is installed at the upper end of the reflux pipe, and the reflux bucket is provided with the first opening at one end away from the reflux pipe, and the position of the first opening is not higher than the designed water surface of the biochemical reaction tank. The aerator is installed and fixed on the aerator stand, and the aerator provides oxygen for the sewage mixture in the biochemical reaction tank, and at the same time generates air lift power to lift the sewage mixture to the reflux bucket and flow back to the bottom of the biochemical reaction tank through the reflux pipe.

[0014] Optionally, the biochemical reaction pool further comprises:

[0015] A mud-water separation device is arranged on the top of the biochemical reaction tank, and is used to separate mud and water from the sewage mixture in the biochemical reaction tank. The obtained clean water is discharged out of the biochemical reaction tank through a pipeline, and the obtained sludge mixture returns to the biochemical reaction tank to continue to participate in the reaction.

[0016] Optionally, the biochemical reaction pool further comprises:

[0017] A stirring device is arranged at the bottom of the biochemical reaction tank and is lower than the aerator stand, and is used to stir the sewage mixture in the tank.

[0018] Optionally, the biochemical reaction pool further comprises:

[0019] A sludge discharge pipe, one end of which is arranged on the wall of the biochemical reaction tank near the bottom, and the other end extends out of the biochemical reaction tank, for discharging excess sludge and emptying the tank water.

[0020] Optionally, the mud-water separation device is at least one of a microfiltration membrane assembly, an ultrafiltration membrane assembly, a circulating clarifier or an aerobic three-phase separator.

[0021] In order to solve the above technical problems, the present application also provides a sewage treatment system, including the biochemical reaction tank as described above.

[0022] The beneficial effects of the embodiments of the present invention are as follows: by designing the reflux device to include a reflux pipe, a reflux bucket and an adjusting cylinder, the reflux pipe is vertically installed in the biochemical reaction tank, the reflux bucket is installed at the upper end of the reflux pipe, and the adjusting cylinder and the reflux bucket are adapted to adjust the flow rate of the liquid flowing from the reflux bucket into the reflux pipe, thereby facilitating the regulation of the reflux amount; on the other hand, the aerator stand is installed on the reflux pipe and is at a preset distance from the lower end of the reflux pipe, and the aerator can be installed on the aerator stand. By installing the aerator stand on the reflux pipe, the functional division of the aerator stand as an aerobic biochemical reaction zone and the anaerobic and anoxic biochemical reaction zone below the aerator stand can be realized, thereby conveniently realizing the vertical flow anoxic aerobic activated sludge wastewater treatment process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 This is a schematic diagram of a structure in which a reflux device is installed in a reaction tank according to an embodiment of the present invention;

[0025] Figure 2 It is a structural schematic diagram of a reflux bucket in one embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the structure of a mud-water separation device installed in a reaction tank according to an embodiment of the present invention.

[0027] Description of the numbers in the figure:

[0028] 1. Reflux pipe, 2. Aerator stand, 3. Reflux bucket, 4. Adjustment cylinder, 5. Assembly flange, 6. Aerator, 7. Mud-water separation device, 8. Stirring device, 11. Reflux hole, 31. First straight cylinder, 32. Reducer, 33. Second straight cylinder, 41. Through hole, 51. First flange, 52. Second flange, 100. Biochemical reaction tank, 101. Water surface. DETAILED DESCRIPTION

[0029] In order to facilitate the understanding of the present invention, the present invention is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more centered elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more centered elements therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this specification are for illustrative purposes only.

[0030] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in this specification and in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0031] See also Figure 1 to Figure 2 , Figure 1 This is a schematic diagram of the structure of a reflux device installed in a reaction tank according to an embodiment of the present invention.

[0032] like Figure 1 to Figure 2 As shown, a reflux device comprises:

[0033] A reflux pipe 1, wherein the reflux pipe 1 is a vertically mounted hollow pipe, and a plurality of reflux holes 11 are arranged on the pipe wall at the lower end of the reflux pipe 1, and an aerator stand 2 is arranged at a preset distance from the lower end of the reflux pipe 1;

[0034] A reflux hopper 3, the reflux hopper 3 comprises a first opening and a second opening, the cross section of the first opening is larger than the cross section of the second opening, and the second opening is connected to the upper end of the reflux pipe 1;

[0035] The regulating cylinder 4 is arranged in the reflux bucket 3 and is matched with the second opening. The regulating cylinder 4 is used to adjust the flow rate of the liquid flowing from the reflux bucket 3 into the reflux pipe 1 .

[0036] During implementation, the reflux device of the present application can be installed in a biochemical reaction tank in a sewage treatment system to realize a vertical flow anoxic aerobic activated sludge sewage treatment process. The reflux pipe 1 is installed in the reaction tank. Specifically, the lower end of the reflux pipe 1 is installed at the bottom of the reaction tank, and a plurality of reflux holes 11 are provided at one end of the reflux pipe 1 close to the bottom of the reaction tank. The reflux pipe 1 is in the shape of a hollow tube. The aerator stand 2 is installed on the reflux pipe 1 and is a certain distance above the bottom of the reaction tank. A plurality of aerators 6 can be installed and fixed on the aerator stand 2, so that two layers of sewage mixture, including an aerobic layer and an anoxic layer, are formed in the reaction tank with the aerator 6 as the dividing line. The aerator stand 2 only needs to be installed on the reflux pipe 1 to realize the installation and fixation of a plurality of aerators 6, thereby simplifying the installation process.

[0037] The upper end of the reflux pipe 1 is connected to the reflux bucket 3. The reflux bucket 3 is funnel-shaped and has a first opening and a second opening. The first opening is lower than the water level of the reaction tank. The second opening is connected to the reflux pipe 1, so that the reflux bucket 3 and the reflux pipe 1 are connected. The regulating cylinder 4 is adapted to the second opening of the reflux bucket 3. For example, the regulating cylinder 4 can be designed to be conical. The outer diameter of one end of the conical regulating cylinder 4 is slightly larger than or equal to the inner diameter of the second opening, so that the regulating cylinder 4 and the second opening can be closely matched. The reflux amount can be adjusted by setting the relative position of the regulating cylinder 4 and the second opening. The function of size, for example, a plurality of (for example, four) adjusting screws are arranged near the second opening of the reflux pipe 1, and the four adjusting screws are on the same horizontal plane. When the adjusting screws are screwed toward the axis of the reflux pipe 1, the space formed between the four adjusting screws becomes smaller, thereby lifting the conical adjusting cylinder 4, increasing the gap formed between the adjusting cylinder 4 and the second opening, thereby adjusting the flow rate flowing from the reflux bucket 3 into the reflux pipe 1 to become larger, and the size of the gap between the second opening and the adjusting cylinder 4 is adjusted by setting the screw-in length of the adjusting screw, thereby adjusting the size of the reflux amount.

[0038] Of course, during implementation, the adjusting cylinder 4 can also be designed to be a straight cylinder, and a plurality of through holes can be axially arranged on the side wall of the adjusting cylinder 4. By setting the length of the adjusting cylinder 4 inserted into the second opening, for example, an internal thread is arranged on the inner surface of the reflux pipe 1 near one end of the second opening, and the adjusting cylinder 4 is provided with an external thread that matches the internal thread of the reflux pipe 1. By rotating the adjusting cylinder 4 to control the relative position between the adjusting cylinder 4 and the second opening, the function of adjusting the reflux amount can be realized.

[0039] In this embodiment, the reflux device is designed to include a reflux pipe 1, a reflux bucket 3 and an adjusting cylinder 4. The reflux pipe 1 can be vertically installed in the biochemical reaction tank, the reflux bucket 3 is installed on the top of the reflux pipe 1, and the adjusting cylinder 4 is adapted to the reflux bucket 3 to adjust the flow rate of the reflux bucket 3 flowing into the reflux pipe 1, so as to facilitate the regulation of the reflux amount; on the other hand, the aerator stand 2 is installed on the reflux pipe 1 and is at a preset distance from the lower end of the reflux pipe 1. Multiple aerators 6 can be installed on the aerator stand 2. By installing the aerator stand 2 on the reflux pipe 1, the installation of multiple aerators 6 can be achieved, which simplifies the installation process. In addition, an aerobic biochemical reaction zone is formed above the aerator 6, and an anaerobic and anoxic biochemical reaction zone is formed below the aerator stand, thereby conveniently realizing a vertical flow anoxic aerobic activated sludge sewage treatment process.

[0040] In an optional embodiment, the reflux bucket 3 includes a first straight cylinder 31, a reducer 32 and a second straight cylinder 33 connected in sequence, one end of the reducer 32 gradually tapers toward the other end, one end of the first straight cylinder 31 is provided with the first opening, the other end of the first straight cylinder 31 is connected to one end of the reducer 32, the other end of the reducer 32 is connected to one end of the second straight cylinder 33, and the second straight cylinder 33 is provided with the second opening at one end away from the reducer 32.

[0041] See also Figure 2 The first straight cylinder 31 is a larger hollow tube, the second straight cylinder 33 is a smaller hollow tube, one end of the reducer 32 is large and the other end is small, the larger end of the reducer 32 is adaptively connected to the first straight cylinder 31, and the smaller end of the reducer 32 is adaptively connected to the second straight cylinder 33. When the reflux bucket 3 and the reflux pipe 1 are connected, the end of the second straight cylinder 33 away from the reducer 32 is connected to the upper end of the reflux pipe 1. During implementation, the reflux bucket 3 can be connected to the reflux pipe 1 through the assembly flange 5 by setting an assembly flange 5. Specifically, the assembly flange 5 includes a first flange 51 and a second flange 52 detachably connected to the first flange 51. The first flange 51 is arranged at the end of the reflux bucket 3 close to the second opening, and the second flange 52 is arranged at the upper end of the reflux pipe 1.

[0042] The assembly flange 5 is used to fix two pipes, pipe fittings or equipment on a flange plate respectively, and then add a flange gasket between the two flange plates and fasten them together with bolts to complete the connection. During implementation, the reflux hopper 3 is fixedly connected to the first flange 51, and the upper end of the reflux pipe 1 is fixedly connected to the second flange. By fastening the first flange 51 and the second flange 52 with bolts, the installation connection between the reflux hopper 3 and the reflux pipe 1 can be achieved, which is convenient for disassembly and installation.

[0043] In some optional embodiments, the adjusting cylinder 4 is matched with the second opening, that is, the adjusting cylinder 4 is matched with the second straight cylinder 33. For example, the adjusting cylinder 4 is a hollow tube with one end sealed, and the side wall of the adjusting cylinder 4 is provided with a plurality of through holes 41 along the axial direction. The other end of the adjusting cylinder 4 is inserted into the second straight cylinder 33, and the relative position between the adjusting cylinder 4 and the second straight cylinder 33 is adjustable. By adjusting the depth of the adjusting cylinder 4 inserted into the second straight cylinder 33, the total water flow area of ​​the through holes 41 located at the reducer 32 is adjusted, thereby realizing the function of adjusting the size of the reflux amount.

[0044] In some embodiments, the present application also provides a biochemical reaction tank 100, including an aerator 6 and a reflux device as described above, the reflux device including a reflux pipe 1, a reflux bucket 2 and an adjusting cylinder 4, the reflux pipe 1 is vertically installed, and its lower end is fixed to the bottom of the biochemical reaction tank 100, the reflux bucket 3 is installed at the upper end of the reflux pipe 1, the reflux bucket 3 is provided with the first opening at one end away from the reflux pipe 1, and the position of the first opening is not higher than the designed water surface of the biochemical reaction tank 100, and multiple aerators 6 are installed and fixed on the aerator stand 2, the aerator 6 provides oxygen for the sewage mixture in the tank body, and at the same time generates air lift power to lift the sewage mixture to the reflux bucket 3 and flow back to the bottom of the biochemical reaction tank 100 through the reflux pipe 1.

[0045] During implementation, the aerator stand 2 is installed in the middle position of the return pipe 1, and several aerators 6 are fixedly installed on the aerator stand 2. The aerator stand 2 can be installed on the return pipe 1 in a detachable manner. For example, the outer wall of the return pipe 1 is provided with latches along the length direction of the return pipe, and the aerator stand 2 is provided with a buckle adapted to the latches, and the buckle extends to form a control handle. For example, the control handle is located on the sewage in the biochemical reaction tank 100. The control handle can control the opening and closing of the buckle to achieve the snap-fit ​​cooperation between the buckle and the latch. For example, when the aerator 6 needs to be moved up two latch positions, it is only necessary to hold the control handle to control the buckle to release the latch, and after lifting the aerator stand 2 by two latch positions, control the buckle to close and engage with the latch, so as to achieve free control of the height of the aerator 6.

[0046] In some embodiments, the end of the reflux bucket 3 provided with the first opening is 0-0.1m below the water surface 101 of the biochemical reaction tank 100, the diameter of the reflux hole 11 is 0.03-0.1m, and the distance between the reflux hole 11 and the bottom of the biochemical reaction tank 100 is 0.05-0.4m. The aerator 6 can provide oxygen for the sewage mixture in the biochemical reaction tank 100, so that the sewage mixture in the biochemical reaction tank 100 is divided by the aerator 6, the upper layer is an aerobic layer, and the lower layer is an anoxic layer; the aerator 6 can also provide air lift power for the sewage mixture in the biochemical reaction tank 100, so that the sewage mixture is lifted upward and flows back from the reflux device to the bottom of the biochemical reaction tank 100 to form a circulation.

[0047] In some embodiments, Figure 3 As shown, the biochemical reaction pool 100 also includes:

[0048] The mud-water separation device 7 is arranged on the top of the biochemical reaction tank 100. The mud-water separation device 7 is used to separate the mud and water in the sewage mixture in the biochemical reaction tank 100. The obtained clean water is the purified water of the biochemical reaction tank 100, which is discharged outside the biochemical reaction tank 100 through a pipe, and the obtained sludge mixture automatically returns to the biochemical reaction tank 100 to continue to participate in the reaction.

[0049] In some optional embodiments, the biochemical reaction pool 100 further includes:

[0050] A sludge discharge pipe, one end of which is arranged at a position near the bottom of the wall of the biochemical reaction tank 100, and the other end extends out of the biochemical reaction tank 100, for discharging excess sludge and emptying the tank water. During implementation, one or more sludge-water separation devices 7 may be installed on the biochemical reaction tank 100, and the sludge-water separation device 7 may be at least one of a microfiltration membrane assembly, an ultrafiltration membrane assembly, a circulation clarifier, or an aerobic three-phase separator.

[0051] After the activated sludge is inoculated and cultivated in the biochemical reaction tank 100, the sewage is introduced into the bottom of the biochemical reaction tank 100, and the activated sludge is aerated and oxygenated by the aerator 6. At the same time, the sewage mixture is lifted to the reflux bucket 3 by the lifting effect of aeration and flows back to the bottom of the biochemical reaction tank 100 through the reflux pipe 1. The reflux amount of the sewage mixture is adjusted by the regulating cylinder 4; a part of the sewage mixture is lifted into the mud-water separation device 7, and mud and water are separated in the mud-water separation device 7, and the clean water is discharged from the biochemical reaction tank 100 through the pipeline, and the concentrated sewage mixture returns downward to the biochemical reaction tank 100 to continue to participate in the reaction.

[0052] In some optional embodiments, the biochemical reaction pool further comprises:

[0053] A stirring device 8 is provided at the bottom of the biochemical reaction tank 100 and is lower than the aerator stand 2. The stirring device 8 is used to stir the sewage mixed liquid in the biochemical reaction tank 100. The stirring device 8 can adopt a perforated pipe or other aeration device to stir the sewage in the tank body of the biochemical reaction tank 100 by aeration, so that the liquid at the bottom of the biochemical reaction tank 100 is evenly mixed. The stirring device 8 can also be a stirring machine such as an underwater flow propeller and a stirring paddle.

[0054] In some optional embodiments, the embodiments of the present application also provide a sewage treatment system, including the biochemical reaction tank 100 as described above. During implementation, the sewage treatment system also includes other sewage treatment process units, such as a magnetic coagulation sedimentation unit and a sand filtration unit, etc. The reflux device in the present application can also be used in other sewage treatment process reaction tanks. Specifically, a reflux device is installed in the reaction tank, the lower end of the reflux pipe 1 is installed at the bottom of the reaction tank, the reflux bucket 3 is installed at the upper end of the reflux pipe 1, and the reflux bucket 3 is provided with a first opening at one end away from the reflux pipe 1. The position of the first opening is lower than the designed water surface of the reaction tank, and one or more aerators 6 are installed and fixed on the aerator stand 2. The aerator 6 provides air lift power and oxygen for the sewage in the tank body. By designing the reflux device to include a reflux pipe 1, a reflux bucket 3 and an adjusting cylinder 4, the adjusting cylinder 4 is adapted to the reflux bucket 3 to adjust the flow rate of the liquid flowing from the reflux bucket 3 into the reflux pipe 1, thereby facilitating the regulation of the reflux amount; on the other hand, the aerator stand 2 is installed on the reflux pipe 1, and by installing the aerator stand 2 on the reflux pipe 1, the installation of multiple aerators 6 can be achieved, thereby simplifying the installation process.

[0055] It should be noted that the preferred embodiments of the present invention are given in the specification and drawings of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. These embodiments are not used as additional limitations on the content of the present invention. The purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. In addition, the above-mentioned technical features continue to be combined with each other to form various embodiments not listed above, which are all regarded as the scope of the present invention; further, for ordinary technicians in this field, they can be improved or transformed according to the above description, and all these improvements and transformations should belong to the protection scope of the claims attached to the present invention.

Claims

1. A biochemical reaction pool (100), characterized in that: It includes an aerator (6) and a reflux device; The reflux device comprises: a reflux pipe (1), the reflux pipe (1) being a hollow pipe installed vertically, and a plurality of reflux holes (11) being arranged on the pipe wall at the lower end of the reflux pipe (1), an aerator stand (2) being arranged at a preset distance from the lower end of the reflux pipe (1), the aerator stand (2) being detachably mounted on the reflux pipe (1), the outer wall of the reflux pipe (1) being provided with latch teeth along the length direction of the reflux pipe, the aerator stand (2) being provided with a latch matched with the latch teeth, and the latch extending to form a control handle, the control handle being used to control the opening and closing of the latch to achieve a latching fit between the latch and the latch teeth; A reflux hopper (3), the reflux hopper (3) comprising a first opening and a second opening, the cross section of the first opening being larger than the cross section of the second opening, the second opening being connected to the upper end of the reflux pipe (1), the reflux hopper (3) comprising a first straight tube (31), a reducer (32) and a second straight tube (33) connected in sequence, one end of the reducer (32) gradually tapering towards the other end, one end of the first straight tube (31) being provided with the first opening, the other end of the first straight tube (31) being connected to one end of the reducer (32), the other end of the reducer (32) being connected to one end of the second straight tube (33), and the second opening being provided at one end of the second straight tube (33) away from the reducer (32); an adjusting cylinder (4), the adjusting cylinder (4) being arranged in the reflux hopper (3) and being adapted to the second opening, the adjusting cylinder (4) being used to adjust the flow rate of the liquid flowing from the reflux hopper (3) into the reflux pipe (1), the adjusting cylinder (4) being a hollow tube with one end sealed, a plurality of through holes (41) being arranged on the side wall of the adjusting cylinder (4), the other end of the adjusting cylinder (4) being inserted into the second straight cylinder (33), and the relative position between the adjusting cylinder (4) and the second straight cylinder (33) being adjustable; The lower end of the reflux pipe (1) is mounted on the bottom of the biochemical reaction pool (100); the reflux bucket (3) is mounted on the upper end of the reflux pipe (1); the first opening is provided at one end of the reflux bucket (3) away from the reflux pipe (1); the position of the first opening is not higher than the designed water surface of the biochemical reaction pool (100); the aerator (6) is mounted and fixed on the aerator stand (2); the aerator (6) provides oxygen for the sewage mixed liquid in the biochemical reaction pool (100), and at the same time generates air lift power to lift the sewage mixed liquid to the reflux bucket (3) and flow back to the bottom of the biochemical reaction pool (100) through the reflux pipe (1).

2. The biochemical reaction pool (100) according to claim 1, characterized in that: The reflux device also includes: An assembly flange (5), the assembly flange (5) comprising a first flange (51) and a second flange (52) detachably connected to the first flange (51), the first flange (51) being arranged at one end of the reflux hopper (3) close to the second opening, and the second flange (52) being arranged at the upper end of the reflux pipe (1).

3. The biochemical reaction pool (100) according to claim 1, characterized in that: The biochemical reaction pool (100) further comprises: A mud-water separation device (7), the mud-water separation device (7) being arranged on the top of the biochemical reaction tank (100), the mud-water separation device (7) being used to separate mud and water from the sewage mixed liquid in the biochemical reaction tank (100), the obtained clean water being discharged out of the biochemical reaction tank (100) through a pipeline, and the obtained sludge mixed liquid being returned to the biochemical reaction tank (100) to continue to participate in the reaction.

4. The biochemical reaction pool (100) according to claim 1, characterized in that: The biochemical reaction pool (100) further comprises: A stirring device (8), the stirring device (8) being arranged at the bottom of the biochemical reaction tank (100) and lower than the aerator stand (2), the stirring device (8) being used to stir the sewage mixed liquid in the tank body.

5. The biochemical reaction pool (100) according to claim 1, characterized in that: The biochemical reaction pool (100) further comprises: A sludge discharge pipe, one end of which is arranged on the wall of the biochemical reaction pool (100) near the bottom, and the other end of which extends out of the biochemical reaction pool (100) and is used for discharging excess sludge and draining pool water.

6. The biochemical reaction pool (100) according to claim 3, characterized in that: The mud-water separation device (7) is at least one of a microfiltration membrane assembly, an ultrafiltration membrane assembly, a circulating clarifier or an aerobic three-phase separator.

7. A sewage treatment system, characterized in that: It comprises a biochemical reaction pool (100) as claimed in any one of claims 1 to 6.

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