Domestic sewage treatment device

Abstract

The invention relates to the technical field of sewage treatment, in particular to a domestic sewage treatment device. An anaerobic tank is arranged in the aerobic tank, a sewage injection pipe and a medicament mixing bin are arranged at the top of the anaerobic tank, a separation plate is arranged at the lower part of the anaerobic tank, a stirring motor is mounted between the separation plate and the bottom of the anaerobic tank, a rotating shaft upwards extends into the anaerobic tank, and a stirring mechanism is arranged on the rotating shaft; and an aerobic filler mechanism is arranged in the aerobic tank. When the domestic sewage treatment device is used, domestic sewage is injected from the sewage injection pipe, an anaerobic reaction is carried out in the anaerobic box, and corresponding chemicals can be added into the chemical mixing bin according to actual requirements; the stirring mechanism fully stirs to enable the anaerobic reaction to be sufficient and uniform, sewage flowing out of the anaerobic tank is further subjected to aerobic reaction in the aerobic tank, and finally the sewage is discharged after being treated by the MBR filter membrane group and the disinfection tank. The anaerobic tank and the aerobic tank are integrated together, so that the occupied area can be greatly reduced, and the sewage treatment device has the advantages of simple structure and convenience in sewage treatment.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and in particular to a domestic sewage treatment device. Background Art

[0002] Domestic sewage is mainly the discharge water generated by various kitchen water, washing water and toilet water used in human life, and is one of the main sources of water pollution.

[0003] In urban living areas, each person discharges hundreds of liters of domestic sewage every day, and the amount is closely related to the living standard. Domestic sewage contains a large amount of organic matter, such as cellulose, starch, sugar, fat, protein, etc.; it also often contains pathogens, viruses and parasite eggs; inorganic salts such as chlorides, sulfates, phosphates, bicarbonates and sodium, potassium, calcium, magnesium, etc.

[0004] Rural domestic sewage comes from wastewater discharged from living facilities such as toilets, kitchens, and shower rooms. Because it contains sediment, grease, soap, food scraps, debris, germs and other substances, it is reflected in the water quality indicators, namely high biochemical oxygen demand (BOD5), chemical oxygen demand (COD), suspended solids (SS), high nitrogen and phosphorus content, and eutrophication. If it is not treated and directly discharged into water bodies (rivers, lakes, seas and groundwater) and soil, the concentration of organic matter in the water and soil will be too high, causing eutrophication of the water and soil. Organic matter in domestic sewage is extremely unstable and easily decomposes to produce foul odors. Bacteria and pathogens multiply in large numbers using organic matter in domestic sewage as nutrition, which can lead to the spread of infectious diseases.

[0005] Biochemical processes are often used in the treatment of domestic sewage. The operation is simple, but it relies on the activity of microorganisms and the addition of carbon source agents to remove pollutants. The activity of microorganisms on domestic sewage is easily affected by climate and environmental changes. The treatment efficiency of existing technologies is low. In addition, anaerobic tanks and aerobic tanks need to be set up separately, which occupies a large area. Therefore, a domestic sewage treatment equipment for domestic sewage pollution is needed. Summary of the invention

[0006] In view of the defects in the prior art, the present invention provides a domestic sewage treatment device.

[0007] The technical solution adopted by the present invention is: a domestic sewage treatment device, comprising an aerobic tank, an MBR filter membrane group and a disinfection box connected in sequence, an anaerobic box is arranged in the aerobic tank, a sewage injection pipe and a reagent mixing bin are arranged on the top of the anaerobic box, an isolation plate is arranged at the bottom, a stirring motor is installed between the isolation plate and the bottom of the anaerobic box, the rotating shaft of the stirring motor extends upward into the anaerobic box, and a stirring mechanism is arranged on the rotating shaft; a discharge hole connected to the aerobic tank is arranged at the bottom of the anaerobic box, and an aerobic filling mechanism is arranged in the aerobic tank.

[0008] To better implement the present invention, the stirring mechanism includes a forward spiral blade and a reverse spiral blade arranged on the rotating shaft, and a material channel with a size larger than the forward spiral blade is arranged on the inner side of the reverse spiral blade. The reverse spiral blade is connected to the rotating shaft through a fixing rod.

[0009] In order to better realize the present invention, a bearing matched with the rotating shaft is arranged on the isolation plate, and a waterproof sealing ring is also matched with the bearing.

[0010] In order to better realize the present invention, the aerobic filling mechanism comprises a vertical pipe, the bottom end of which is fixedly connected to the bottom of the aerobic pool, and a plurality of filling pieces are sleeved on the vertical pipe.

[0011] In order to better realize the present invention, the filler member includes a sleeve matched with the vertical pipe, a filler body is arranged in the middle of the sleeve, and annular limiting parts are arranged at both ends.

[0012] In order to better implement the present invention, the top of the vertical pipe is connected to an air pump, and circumferentially distributed aeration holes are provided on the vertical pipe.

[0013] In order to better realize the present invention, a plurality of medicine hoppers are connected to the medicine mixing bin and matched with corresponding medicine valves.

[0014] To better implement the present invention, the upper part of the aerobic pool is connected to the MBR filter membrane group through a first pipeline, and the lower part of the MBR filter membrane group is connected to the disinfection box through a second pipeline, and a suction pump is arranged on the second pipeline.

[0015] In order to better realize the present invention, a quartz sand filter layer and an activated carbon filter layer are provided in the disinfection box, and a discharge port and a corresponding drain valve are provided at the lower part of the disinfection box.

[0016] In order to better realize the present invention, a return pipe connected to a sewage injection pipe is arranged at the lower part of the MBR filter membrane group, and a mud discharge pipe and a corresponding mud discharge valve are arranged at the lower part of the return pipe.

[0017] The beneficial effects of the present invention are embodied in: a domestic sewage treatment device of the present invention, through the cooperation of an aerobic tank, an MBR filter membrane group, a disinfection box, an anaerobic box, a sewage injection pipe, a chemical mixing bin, a partition plate, a stirring motor, a rotating shaft, a stirring mechanism, and an aerobic filler mechanism, when in use, domestic sewage is injected from the sewage injection pipe, and an anaerobic reaction is carried out in the anaerobic box, and corresponding chemicals can be added to the chemical mixing bin according to actual needs; the stirring mechanism fully stirs to make the anaerobic reaction sufficient and uniform, and the sewage flowing out of the anaerobic box further undergoes an aerobic reaction in the aerobic tank, and finally is discharged after being treated by the MBR filter membrane group and the disinfection box. Integrating the anaerobic box and the aerobic tank together can greatly reduce the floor space, and has the advantages of simple structure and convenient sewage treatment.

[0018] The stirring mechanism comprises a forward spiral blade and a reverse spiral blade arranged on a rotating shaft, a material channel having a size larger than that of the forward spiral blade is arranged on the inner side of the reverse spiral blade, and the reverse spiral blade is connected to the rotating shaft through a fixing rod. With such a design, the sewage injected from the sewage injection pipe flows forward in the material channel under the action of the forward spiral blade, and at the same time, the reverse spiral blade rotates, allowing the sewage to flow in the reverse direction outside the material channel, thus forming a convection environment, greatly improving the stirring efficiency, and making the anaerobic reaction more sufficient and uniform.

[0019] The isolation plate is provided with a bearing matched with the rotating shaft and a waterproof sealing ring, so that the sealing performance can be greatly improved and the service life of the stirring motor can be extended.

[0020] The aerobic filling mechanism comprises a vertical pipe, the bottom end of which is fixedly connected to the bottom of the aerobic pool, and a plurality of filling pieces are sleeved on the vertical pipe. After such a design, different numbers of filling pieces can be sleeved on the vertical pipe according to actual use conditions, which is flexible and convenient and saves costs.

[0021] The packing member includes a sleeve matched with the vertical tube, a packing body is arranged in the middle of the sleeve, and an annular limiting part is arranged at both ends. The sleeve matches with the vertical tube and can slide freely along the vertical tube. The annular limiting parts of two adjacent packing members conflict with each other to play a limiting role.

[0022] The top of the vertical pipe is connected to an air pump, and the vertical pipe is provided with circumferentially distributed aeration holes. With this design, the vertical pipe can be directly inflated by the air pump to aerate the aeration holes, and no special aeration device is required, which not only saves equipment costs but also reduces occupied space.

[0023] In order to better realize the present invention, a plurality of medicine hoppers are connected to the medicine mixing bin and matched with corresponding medicine valves. After such design, medicines can be put into the medicine hoppers to improve the efficiency of anaerobic reaction in the anaerobic box.

[0024] The lower part of the aerobic pool is connected to the MBR filter membrane group through a first pipe, and a suction pump is arranged on the first pipe. The upper part of the MBR filter membrane group is connected to the disinfection box through a second pipe. After this design, the suction pump is started to allow the sewage that has undergone aerobic reaction to enter the MBR filter membrane group along the first pipe, and then enter the disinfection box through the second pipe.

[0025] A quartz sand filter layer and an activated carbon filter layer are provided in the disinfection box, and a discharge port and a corresponding drain valve are provided at the lower part of the disinfection box. After disinfection and filtration by the quartz sand filter layer and the activated carbon filter layer, the clean water obtained can be discharged, and the drain valve adopts a solenoid valve, which can be conveniently controlled remotely. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0027] Figure 1 A structural schematic diagram of a domestic sewage treatment device of the present invention; Figure 2 A structural schematic diagram of a stirring mechanism of a domestic sewage treatment device of the present invention; Figure 3 A schematic structural diagram of a filler member of a domestic sewage treatment device of the present invention; In the attached drawings, 1 is an aerobic tank, 2 is an anaerobic tank, 3 is a sewage injection pipe, 4 is a pharmaceutical mixing bin, 5 is a pharmaceutical bucket, 6 is a pharmaceutical valve, 7 is a partition plate, 8 is a stirring motor, 9 is a rotating shaft, 10 is a bearing, 11 is a vertical pipe, 12 is a packing member, 13 is a first pipeline, 14 is a suction pump, 15 is a MBR filter membrane group, 16 is a second pipeline, 17 is a disinfection tank, 18 is a quartz sand filter layer, 19 is an activated carbon filter layer, 20 is a discharge port, 21 is a drain valve, 22 is a packing body, 23 is a casing, 24 is an annular limiter, 25 is a honeycomb hole, 26 is a forward spiral blade, 27 is a reverse spiral blade, 28 is a fixing rod, 29 is a reflux pipe, 30 is a mud discharge pipe, and 31 is a mud discharge valve. DETAILED DESCRIPTION

[0028] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention. In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, rather than all the embodiments. The components of the embodiments of the present disclosure described and shown in the drawings here can be arranged and designed in various different configurations.

[0029] In the description of the present disclosure, it should be noted that the orientation or positional relationship indicated by the terms "upper", "inner", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the disclosed product is usually placed when in use, and is only for the convenience of describing the present disclosure and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present disclosure. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0030] In the description of the present disclosure, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0031] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by those skilled in the art in the field to which the present invention relates.

[0032] Example: like Figures 1 to 3As shown, a domestic sewage treatment device of the present invention comprises an aerobic tank 1, an MBR filter membrane group 15 and a disinfection box 17 which are connected in sequence, an anaerobic box 2 is arranged in the aerobic tank 1, a sewage injection pipe 3 and a reagent mixing bin 4 are arranged on the top of the anaerobic box 2, an isolation plate 7 is arranged at the bottom, a stirring motor 8 is installed between the isolation plate 7 and the bottom of the anaerobic box 2, a rotating shaft 9 of the stirring motor 8 extends upward into the anaerobic box 2, and a stirring mechanism is arranged on the rotating shaft 9; a discharge hole connected to the aerobic tank 1 is arranged at the bottom of the anaerobic box 2, and an aerobic filler mechanism is arranged in the aerobic tank 1. A domestic sewage treatment device of the present invention is provided by the cooperation of an aerobic tank 1, an MBR filter membrane group 15, a disinfection box 17, an anaerobic box 2, a sewage injection pipe 3, a reagent mixing chamber 4, a partition plate 7, a stirring motor 8, a rotating shaft 9, a stirring mechanism and an aerobic filling mechanism. When in use, domestic sewage is injected from the sewage injection pipe 3 and an anaerobic reaction is carried out in the anaerobic chamber 2. According to actual needs, corresponding reagents can be added to the reagent mixing chamber 4; the stirring mechanism fully stirs to make the anaerobic reaction sufficient and uniform, and the sewage flowing out of the anaerobic chamber 2 further undergoes an aerobic reaction in the aerobic tank, and finally is discharged after being treated by the MBR filter membrane group 15 and the disinfection box 2. Integrating the anaerobic chamber 2 and the aerobic tank 1 together can greatly reduce the floor space, and has the advantages of simple structure and convenient sewage treatment.

[0033] As a preferred embodiment, the stirring mechanism includes a forward spiral blade 26 and a reverse spiral blade 27 arranged on the rotating shaft 9, a material channel having a size larger than the forward spiral blade 26 is arranged inside the reverse spiral blade 27, and the reverse spiral blade 27 is connected to the rotating shaft 9 through a fixing rod 28. In this embodiment, the stirring mechanism includes a forward spiral blade 26 and a reverse spiral blade 27 arranged on the rotating shaft 9, a material channel having a size larger than the forward spiral blade 26 is arranged inside the reverse spiral blade 27, and the reverse spiral blade 27 is connected to the rotating shaft 9 through a fixing rod 28. After such a design, the sewage injected from the sewage injection pipe 3 flows forward in the material channel under the action of the forward spiral blade 26, and at the same time, the reverse spiral blade rotates 27, so that the sewage flows in the reverse direction outside the material channel, thus forming a convection environment, greatly improving the stirring efficiency, and making the anaerobic reaction more sufficient and uniform.

[0034] As a preferred embodiment, a bearing 10 is provided on the isolation plate 7 to cooperate with the rotating shaft 9, and a waterproof sealing ring is provided. In this embodiment, a bearing 10 is provided on the isolation plate 7 to cooperate with the rotating shaft 9, and a waterproof sealing ring is provided. After such a design, the sealing performance can be greatly improved, and the service life of the stirring motor can be extended.

[0035] As a preferred embodiment, the aerobic filling mechanism includes a vertical pipe 11, the bottom end of which is fixedly connected to the bottom of the aerobic pool 1, and a plurality of filling pieces 12 are sleeved on the vertical pipe 11. In this embodiment, the aerobic filling mechanism includes a vertical pipe 11, the bottom end of which is fixedly connected to the bottom of the aerobic pool 1, and a plurality of filling pieces 12 are sleeved on the vertical pipe 11. After such a design, different numbers of filling pieces 12 can be sleeved on the vertical pipe 11 according to actual use conditions, which is flexible and convenient, and saves costs.

[0036] As a preferred embodiment, the packing member 12 includes a sleeve 23 that cooperates with the vertical tube 11, a packing body 22 is arranged in the middle of the sleeve 23, an annular limiting portion 24 is arranged at both ends, and a honeycomb hole 25 for increasing the contact area is arranged on the packing body 22. In this embodiment, the packing member 12 includes a sleeve 23 that cooperates with the vertical tube 11, a packing body 22 is arranged in the middle of the sleeve 23, an annular limiting portion 24 is arranged at both ends, and a honeycomb hole 25 for increasing the contact area is arranged on the packing body 22. The sleeve 23 cooperates with the vertical tube 11 and can slide freely along the vertical tube 11. The annular limiting portions 24 of two adjacent packing members 12 conflict with each other to play a limiting role.

[0037] As a preferred embodiment, the top of the vertical pipe 11 is connected to an air pump, and aeration holes distributed circumferentially are provided on the vertical pipe 11. In this embodiment, the top of the vertical pipe 11 is connected to an air pump, and aeration holes distributed circumferentially are provided on the vertical pipe 11. With this design, the vertical pipe 11 can be directly inflated by the air pump to aerate the aeration holes, without the need to set up a special aeration device, which not only saves equipment costs but also reduces occupied space.

[0038] As a preferred embodiment, a plurality of medicine hoppers 5 are connected to the medicine mixing chamber 4, and are matched with corresponding medicine valves 6. In this embodiment, a plurality of medicine hoppers 5 are connected to the medicine mixing chamber 4, and are matched with corresponding medicine valves 6. With this design, medicines can be put into the medicine hoppers 5 to improve the efficiency of anaerobic reaction in the anaerobic box 2.

[0039] As a preferred embodiment, the upper part of the aerobic pool 1 is connected to the MBR filter membrane group 15 through the first pipe 13, the lower part of the MBR filter membrane group 15 is connected to the disinfection box 17 through the second pipe 16, and a suction pump 14 is provided on the second pipe 16. In this embodiment, the upper part of the aerobic pool 1 is connected to the MBR filter membrane group 15 through the first pipe 13, the lower part of the MBR filter membrane group 15 is connected to the disinfection box 17 through the second pipe 16, and a suction pump 14 is provided on the second pipe 16. After such a design, the suction pump 14 is started to allow the sewage that has undergone aerobic reaction to enter the MBR filter membrane group 15 along the first pipe, and then enter the disinfection box 17 through the second pipe 16.

[0040] Membrane bioreactor (MBR) is a new water treatment technology that combines a membrane separation unit with a biological treatment unit. It uses membrane components to replace secondary sedimentation tanks to maintain high active sludge concentration in the bioreactor to reduce the land occupation of sewage treatment facilities, and reduce the amount of sludge by maintaining a low sludge load. Due to its effective interception effect, the membrane bioreactor can retain microorganisms with a long generation cycle, which can achieve deep purification of sewage. At the same time, nitrifying bacteria can fully reproduce in the system, and its nitrification effect is obvious, providing the possibility of deep phosphorus and nitrogen removal. Compared with traditional biochemical water treatment technology, this process not only effectively achieves the purpose of mud and water separation, but also has incomparable advantages over traditional tertiary sewage treatment processes: 1. Efficient solid-liquid separation, the separation effect is much better than the traditional sedimentation tank, the effluent water quality is good, the effluent suspended solids and turbidity are close to zero, and it can be directly reused, realizing the resource utilization of sewage.

[0041] 2. The efficient interception effect of the membrane allows the microorganisms to be completely retained in the bioreactor, achieving complete separation of the reactor hydraulic retention time (HRT) and sludge age (SRT), and the operation control is flexible and stable.

[0042] 3. Since MBR combines the aeration tank and the secondary sedimentation tank of traditional sewage treatment into one and replaces all the process facilities of the tertiary treatment, it can greatly reduce the floor space and save civil engineering investment.

[0043] 4. It is conducive to the retention and reproduction of nitrifying bacteria, and the system has high nitrification efficiency. By changing the operation mode, it can also have the functions of deammoniation and phosphorus removal.

[0044] 5. Since the sludge age can be very long, the degradation efficiency of difficult-to-degrade organic matter can be greatly improved.

[0045] 6. The reactor operates under high volumetric load, low sludge load and long sludge age. The residual sludge production is extremely low. Since the sludge age can be infinitely long, zero sludge discharge can be achieved in theory.

[0046] As a preferred embodiment, a quartz sand filter layer 18 and an activated carbon filter layer 19 are provided in the disinfection box 17, and a discharge port 20 and a corresponding drain valve 21 are provided at the lower part of the disinfection box 17. In this embodiment, a quartz sand filter layer 18 and an activated carbon filter layer 19 are provided in the disinfection box 17, and a discharge port 20 and a corresponding drain valve 21 are provided at the lower part of the disinfection box 17. After disinfection and filtration by the quartz sand filter layer 18 and the activated carbon filter layer 19, the clean water obtained can be discharged, and the drain valve 21 adopts a solenoid valve, which can be conveniently controlled remotely.

[0047] As a preferred embodiment, a return pipe 29 connected to the sewage injection pipe 3 is provided at the lower part of the MBR filter membrane group 15, and a mud discharge pipe 30 and a corresponding mud discharge valve 31 are provided at the lower part of the return pipe 29. With this design, it is convenient for the return sewage to fully react, and the sludge can be discharged in time to avoid blockage.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A domestic sewage treatment device, characterized in that: The invention comprises an aerobic tank (1), an MBR filter membrane group (15) and a disinfection box (17) which are connected in sequence. An anaerobic box (2) is arranged in the aerobic tank (1). A sewage injection pipe (3) and a reagent mixing chamber (4) are arranged at the top of the anaerobic box (2). An isolation plate (7) is arranged at the bottom. A stirring motor (8) is installed between the isolation plate (7) and the bottom of the anaerobic box (2). The rotating shaft (9) of the stirring motor (8) extends upward into the anaerobic box (2). A stirring mechanism is arranged on the rotating shaft (9). A discharge hole connected to the aerobic tank (1) is arranged at the bottom of the anaerobic box (2). An aerobic filling mechanism is arranged in the aerobic tank (1).

2. A domestic sewage treatment device according to claim 1, characterized in that: The stirring mechanism comprises a forward spiral blade (26) and a reverse spiral blade (27) arranged on a rotating shaft (9); a material channel having a larger size than the forward spiral blade (26) is arranged inside the reverse spiral blade (27); and the reverse spiral blade (27) is connected to the rotating shaft (9) via a fixing rod (28).

3. A domestic sewage treatment device according to claim 2, characterized in that: A bearing (10) matched with the rotating shaft (9) is arranged on the isolation plate (7), and is also matched with a waterproof sealing ring.

4. A domestic sewage treatment device according to claim 1, characterized in that: The aerobic filling mechanism comprises a vertical pipe (11), the bottom end of the vertical pipe (11) is fixedly connected to the bottom of the aerobic pool (1), and a plurality of filling pieces (12) are sleeved on the vertical pipe (11).

5. A domestic sewage treatment device according to claim 4, characterized in that: The packing element (12) comprises a sleeve (23) matched with the vertical pipe (11), a packing body (22) is arranged in the middle of the sleeve (23), and annular limiting portions (24) are arranged at both ends.

6. A domestic sewage treatment device according to claim 4, characterized in that: The top of the vertical pipe (11) is connected to an air pump, and aeration holes distributed circumferentially are provided on the vertical pipe (11).

7. A domestic sewage treatment device according to claim 1, characterized in that: A plurality of medicine hoppers (5) are connected to the medicine mixing chamber (4), and are matched with corresponding medicine valves (6).

8. A domestic sewage treatment device according to claim 1, characterized in that: The upper part of the aerobic pool (1) is connected to an MBR filter membrane group (15) via a first pipe (13), and the lower part of the MBR filter membrane group (15) is connected to a disinfection box (17) via a second pipe (16), and a suction pump (14) is provided on the second pipe (16).

9. A domestic sewage treatment device according to claim 8, characterized in that: A quartz sand filter layer (18) and an activated carbon filter layer (19) are provided in the disinfection box (17), and a discharge port (20) and a corresponding drainage valve (21) are provided at the lower part of the disinfection box (17).

10. A domestic sewage treatment device according to claim 9, characterized in that: A return pipe (29) connected to the sewage injection pipe (3) is provided at the lower part of the MBR filter membrane group (15), and a mud discharge pipe (30) and a corresponding mud discharge valve (31) are provided at the lower part of the return pipe (29).

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