Multi-household combined domestic sewage treatment system

Abstract

The application relates to the technical field of sewage treatment, and provides a multi-household combined domestic sewage treatment system which comprises a pretreatment unit, a percolation tank, a water distribution assembly and a wall scraping cleaning piece, the percolation tank comprises a planted topsoil layer, a water distribution layer, a percolation layer and a soil treatment layer; the water distribution assembly comprises a water distribution pipe network and a driving source, the water distribution pipe network comprises a water inlet main pipe, a first water inlet pipe, a second water inlet pipe, a water distribution main pipe and a water distribution branch pipe, the water inlet main pipe is in communication with the first water inlet pipe and the second water inlet pipe, the first water inlet pipe is provided with a first cut-off piece, and the second water inlet pipe is provided with a second cut-off piece; two water distribution main pipes are arranged at intervals, the first water inlet pipe is in communication with one water distribution main pipe, the second water inlet pipe is in communication with the other water distribution main pipe, the water distribution main pipe is provided with a residue discharge pipe at the bottom, and the water distribution main pipe and the residue discharge pipe are provided with an on-off piece at the communication position; and the wall scraping cleaning piece is slidingly arranged in the water distribution branch pipe. The application can reduce the maintenance difficulty of the water distribution system in the long-term use process.

Description

Technical Field

[0001] This application relates to the technical field of wastewater treatment, and in particular to a multi-household combined domestic wastewater treatment system. Background Technology

[0002] In mountainous and hilly areas, a large number of residents live scattered around core villages, and the treatment of domestic sewage from these dispersed households presents significant difficulties and challenges for local governments. Due to the dispersed nature of the residences, the traditional model of collecting sewage through pipe networks and then centralizing treatment facilities is extremely costly, resulting in a severe imbalance between the investment in the pipe network and the volume of sewage collected, leading to very low investment efficiency. Currently, "high-load underground infiltration" technology is widely used to address the problem of treating domestic sewage from multiple households. High-load underground infiltration is an improved infiltration system that, through optimized design and material selection, increases the hydraulic load capacity per unit area, thereby achieving highly efficient sewage purification in a relatively small land area.

[0003] Clogging of the water distribution system within the infiltration bed is a common problem in high-load underground infiltration systems. It not only affects treatment efficiency but can also lead to the failure of the entire system. To solve the problem of clogging in the water distribution system, a self-cleaning pipeline system has been developed. This system uses cleaning brushes installed inside the water distribution pipes and underwater mechanical drive to clean the pipes, thus resolving the clogging issue.

[0004] However, the cleaning brush and its drive mechanism contain multiple moving parts, which are prone to wear or damage during long-term operation, leading to frequent parts replacements and inconvenient maintenance. Furthermore, because the drive mechanism operates in a humid environment containing chemicals, metal parts may corrode, affecting the equipment's lifespan and performance stability. Summary of the Invention

[0005] In order to optimize the cleaning method of the water distribution system and reduce the maintenance difficulty of the water distribution system during long-term use, this application provides a multi-household domestic sewage treatment system.

[0006] This application provides a multi-household combined domestic sewage treatment system, which adopts the following technical solution:

[0007] A multi-household combined domestic sewage treatment system, comprising:

[0008] The pretreatment unit includes a bar screen, a grit chamber, and a equalization tank connected in sequence.

[0009] The infiltration pond is connected to the equalization pond. The infiltration pond includes, from top to bottom, a planting topsoil layer, a water distribution layer, an infiltration layer, and a soil treatment layer.

[0010] A water distribution assembly includes a water distribution network and a drive source. The water distribution network includes a main inlet pipe, a first inlet pipe, a second inlet pipe, a main distribution pipe, and branch distribution pipes. The main inlet pipe is connected to both the first and second inlet pipes. A first flow-blocking device is installed on the first inlet pipe, and a second flow-blocking device is installed on the second inlet pipe. The main distribution pipe and branch distribution pipes are located within the water distribution layer. Two main distribution pipes are spaced apart. The first inlet pipe is connected to one of the main distribution pipes, and the second inlet pipe is connected to the other main distribution pipe. The main water distribution pipe is connected to the main water distribution pipe, and a slag discharge pipe is connected to the bottom of the main water distribution pipe. A switch is provided at the connection between the main water distribution pipe and the slag discharge pipe. The switch is used to control the opening and closing of the main water distribution pipe and the slag discharge pipe. Multiple branch water distribution pipes are provided between the two main water distribution pipes. One end of each branch water distribution pipe is connected to one main water distribution pipe, and the other end is connected to another main water distribution pipe. Multiple water distribution holes are provided on each branch water distribution pipe. The driving source is used to drive the water in the regulating tank to flow into the main water inlet pipe.

[0011] The wall-scraping cleaning component is slidably disposed inside the water distribution branch pipe, and includes an elastic support and a wall-scraping blade disposed around the elastic support. The wall-scraping blade abuts against the inner wall of the water distribution branch pipe.

[0012] By adopting the above technical solution, the clogging problem of the water distribution system in high-load underground infiltration systems can be effectively solved. Firstly, by alternately introducing water through the first and second inlet pipes, the flow direction within the distribution branch pipes is intermittently changed, thereby backwashing residual impurities within the branch pipes. When water is introduced through the first inlet pipe, the on / off element near it is closed, while the one near the second inlet pipe is open; conversely, when water is introduced through the second inlet pipe, the on / off element near it is closed, and the one near the first inlet pipe is open. Secondly, the wall-scraping cleaning component slides along the distribution branch pipe under the action of water flow, driving the scraper blades to clean the inner wall of the branch pipe, scraping away contaminants that flow into the slag discharge pipe under the impact of the water flow. This design not only improves the cleaning efficiency of the water distribution system but also reduces the maintenance difficulty caused by the cleaning brush and its drive mechanism, extending the service life and performance stability of the equipment.

[0013] Optionally, a first concentrator is provided at the connection between the main water distribution pipe and the branch water distribution pipe, and the cross-sectional area of ​​the first concentrator gradually decreases towards the branch water distribution pipe.

[0014] By adopting the above technical solution, the setting of the first flow-concentrating cylinder can effectively reduce the turbulence and vortex phenomenon of water flow between the main water distribution pipe and the branch water distribution pipe, improve the stability and uniformity of water flow; increase the water flow velocity to enhance the flushing force on the inner wall of the branch water distribution pipe when water is introduced, further improve the effect of backwashing, and help remove pollutants attached to the inner wall of the branch water distribution pipe.

[0015] Optionally, a second concentrator is also provided inside the water distribution branch pipe. The second concentrator includes a narrow section and expansion sections disposed at both ends of the narrow section. The cross-sectional area of ​​the expansion sections gradually decreases towards the narrow section.

[0016] The wall-scraping cleaning component is provided between the first flow-concentrating cylinder and the second flow-concentrating cylinder.

[0017] By adopting the above technical solution, the second concentrator can effectively increase the water flow velocity in the water distribution branch pipe, promote the suspension and transport of particles in the water, and reduce sedimentation. Simultaneously, the wall-scraping cleaning component is located between the first and second concentrators, making it easier for the component to move under the influence of water flow during water intake, effectively removing dirt from the inner wall of the water distribution branch pipe, ensuring the smooth flow of the water distribution system, extending the service life of the equipment, and reducing maintenance frequency.

[0018] Optionally, a force-bearing plate is also fixed on the elastic support, and the force-bearing plate is inclined relative to the length direction of the water distribution branch pipe.

[0019] By adopting the above technical solution, the force-bearing plate can effectively increase the force of the water flow on the wall-scraping cleaning component, making the wall-scraping cleaning component slide more smoothly in the water distribution branch pipe and improving the cleaning effect. At the same time, the inclined force-bearing plate can guide the direction of water flow, further enhancing the flushing force of the water flow on the inside of the water distribution branch pipe, which helps to more thoroughly remove pollutants adhering to the inner wall of the water distribution branch pipe.

[0020] Optionally, the percolation layer includes a sand and gravel filter layer, a main percolation layer, and a fine sand buffer layer.

[0021] By adopting the above technical solution, the sand and gravel filter layer can initially remove large suspended solids from wastewater, reducing the burden on subsequent treatment units. The main infiltration layer, as the primary treatment area, can efficiently adsorb and degrade organic matter and other harmful substances in the wastewater. The fine sand buffer layer further purifies the water quality while preventing fine particles from entering the water distribution system and causing blockages.

[0022] Optionally, a temperature control component is also included, comprising an underground heat collection pipe, a geothermal pump, and an in-pool heat exchange pipe assembly. The underground heat collection pipe is located below the in-pool heat exchange pipe assembly and is connected to the in-pool heat exchange pipe assembly. The in-pool heat exchange pipe assembly is located within the infiltration tank, and the geothermal pump is used to drive the heat exchange medium in the underground heat collection pipe to move into the in-pool heat exchange pipe assembly.

[0023] By adopting the above technical solution, the design of the temperature control component allows the geothermal energy collected by the underground heat collection pipes to be transferred to the heat exchange tube group in the pool via a geothermal pump, thereby heating the water in the infiltration pool, preventing the decline in microbial activity under low-temperature conditions, and ensuring the smooth progress of the biodegradation process. At the same time, heat transfer can also reduce energy consumption and improve the overall operating economy of the system.

[0024] Optionally, the heat exchange tube assembly in the pool includes heat exchange tubes and a heat exchange jacket. The heat exchange jacket is fitted outside the water distribution branch pipe, and the heat exchange jacket is also provided with a clearance hole corresponding to the water distribution hole.

[0025] By adopting the above technical solution, the heat exchange jacket is installed outside the water distribution branch pipe, which can effectively increase the water temperature inside the water distribution branch pipe and prevent oil contaminants inside the water distribution branch pipe from solidifying due to excessively low temperature in low-temperature environments, thereby avoiding blockage problems caused by this. The design of the clearance hole ensures the normal operation of the water distribution hole and avoids affecting the uniformity of water distribution due to the jacket obstruction, thus ensuring the effectiveness of temperature control without affecting the normal operation of the water distribution system.

[0026] Optionally, an insulation layer is provided on the inner wall of the infiltration tank.

[0027] By adopting the above technical solution, the insulation layer installed on the inner wall of the infiltration tank can effectively reduce the impact of temperature changes on the internal environment of the infiltration tank, improving the system's stability and treatment efficiency. Especially in cold seasons, the insulation layer can prevent the temperature inside the tank from becoming too low, which would lead to a decrease in microbial activity and ensure effective wastewater treatment.

[0028] In summary, this application includes at least one of the following beneficial effects:

[0029] 1. In this application, the first and second intercepting components are used to allow water to enter the first and second inlet pipes alternately, thereby achieving the purpose of intermittently changing the water flow direction in the water distribution branch pipe, effectively backwashing residual impurities, and reducing the risk of blockage;

[0030] 2. In this application, the wall-scraping cleaning component inside the water distribution branch pipe slides with the water flow, driving the wall-scraping blade to clean the inner wall of the water distribution branch pipe, scraping off and removing contaminants on the inner wall, thereby improving the self-cleaning ability of the system and extending the service life of the equipment.

[0031] 3. The design of the slag discharge pipe and the on / off components in this application enables the cleaned impurities to be smoothly discharged from the system, avoiding secondary pollution and ensuring the stable operation and processing efficiency of the system. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of a multi-household combined domestic sewage treatment system according to an embodiment of this application;

[0033] Figure 2 This is a cross-sectional structural diagram of the infiltration tank in the embodiments of this application;

[0034] Figure 3 This is a cross-sectional view of the water distribution branch pipe in an embodiment of this application;

[0035] Figure 4 yes Figure 3 A magnified schematic diagram of the local structure at point A;

[0036] Explanation of reference numerals in the attached drawings: 1. Pretreatment unit; 11. Grille; 12. Sedimentation tank; 13. Equalization tank; 2. Infiltration tank; 21. Topsoil layer; 22. Water distribution layer; 23. Infiltration layer; 231. Sand and gravel filter layer; 232. Main infiltration layer; 233. Fine sand buffer layer; 24. Soil treatment layer; 25. Insulation layer; 3. Water distribution assembly; 31. Water distribution network; 311. Main inlet pipe; 312. First inlet pipe; 313. Second inlet pipe; 314. Main water distribution pipe; 315. Water distribution pipe. Branch pipe; 3151, water distribution hole; 32, first interceptor; 33, second interceptor; 34, slag discharge pipe; 35, on / off component; 36, drive source; 4, wall scraping and cleaning component; 41, elastic support; 42, wall scraping blade; 43, stress plate; 5, first concentrator; 6, second concentrator; 61, narrow section; 62, widening section; 7, temperature regulating component; 71, underground heat collection pipe; 72, geothermal pump; 73, heat exchanger tube assembly in the pool; 731, heat exchanger tube; 732, heat exchange jacket; 7321, clearance hole. Detailed Implementation

[0037] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0038] This application provides a multi-household domestic sewage treatment system.

[0039] Reference Figure 1 and Figure 2The multi-household domestic wastewater treatment system includes a pretreatment unit 1, a percolation tank 2, and a water distribution assembly 3. The pretreatment unit 1 comprises a screen trough 11, a grit chamber 12, and a regulating tank 13 connected in sequence. Wastewater flows sequentially along the screen trough 11 and grit chamber 12 into the regulating tank 13 to initially remove large particulate impurities and suspended solids, providing clean water for subsequent treatment. The percolation tank 2 consists of a topsoil layer 21, a water distribution layer 22, a percolation layer 23, and a soil treatment layer 24, arranged from top to bottom. The topsoil layer 21 is mainly used for planting plants to absorb water and nutrients. The water distribution layer 22 is responsible for evenly distributing wastewater. The percolation layer 23 mainly includes a sand and gravel filter layer 231, a main percolation layer 232, and a fine sand buffer layer 233. The main percolation layer 232 is filled with filter media. The filler materials are mostly natural or synthetic materials with good air and water permeability, such as ceramsite, zeolite, and coconut shell charcoal, to enhance biological activity and adsorption performance, thus playing a role in filtration and purification. The treated wastewater then permeates into the soil treatment layer 24, where it is completely purified before being discharged.

[0040] Reference Figure 1 and Figure 2 The water distribution assembly 3 mainly includes a water distribution network 31 and a drive source 36. The drive source 36 is specifically configured as a booster pump, located within the regulating tank 13. The water distribution network 31 is located within the water distribution layer 22, which is filled with sand and gravel. The water distribution network 31 specifically includes an inlet main pipe 311, a first inlet pipe 312, a second inlet pipe 313, and a water distribution main pipe 314. The inlet main pipe 311 is located outside the infiltration tank 2 and is connected to the drive source 36. The other end of the inlet main pipe 311 is connected to both the first inlet pipe 312 and the second inlet pipe 313. A first interceptor 32 is installed on the first inlet pipe 312, and a second interceptor 33 is installed on the second inlet pipe 313. In this embodiment, both the first interceptor 32 and the second interceptor 33 are configured as flow-stopping valves. Two main water distribution pipes 314 are spaced apart within the water distribution layer 22. A first inlet pipe 312 is connected to one main water distribution pipe 314, and a second inlet pipe 313 is connected to the other main water distribution pipe 314. Each main water distribution pipe 314 has several slag discharge pipes 34 connected to its bottom. A switching element 35 is installed at the connection point between the main water distribution pipe 314 and the slag discharge pipes 34. The switching element 35 controls the opening and closing of the main water distribution pipe 314 and the slag discharge pipes 34. In this embodiment, the switching element 35 is specifically configured as a solenoid valve fixed to the slag discharge pipe 34. (Refer to...) Figure 3 and Figure 4Multiple water distribution branch pipes 315 are connected between the two main water distribution pipes 314, and the multiple water distribution branch pipes 315 are arranged in parallel. Each water distribution branch pipe 315 has multiple water distribution holes 3151. The drive source 36 is used to drive the water in the regulating tank 13 to flow into the main water inlet pipe 311. When the drive source 36 is started, the water in the regulating tank 13 is driven to enter the first water inlet pipe 312 or the second water inlet pipe 313 along the main water inlet pipe 311 and then flow into the main water distribution pipe 314, and then into the water distribution branch pipes 315, and is discharged along the water distribution holes 3151 on the water distribution branch pipes 315.

[0041] In this embodiment, the diameters of the first inlet pipe 312 and the second inlet pipe 313 can be selected according to specific needs to ensure sufficient flow supply. The drive source 36 is specifically configured as a booster pump located within the regulating tank 13.

[0042] Reference Figure 4 The wall-scraping cleaning component 4 is slidably disposed within the water distribution branch pipe 315. The wall-scraping cleaning component 4 includes an elastic support 41 and multiple scraping blades 42 fixed to the periphery of the elastic support 41. The outer walls of the scraping blades 42 abut against the inner wall of the water distribution branch pipe 315. The elastic support 41 can be made of spring or rubber, providing good elasticity and durability. The scraping blades 42 can be made of soft plastic or nylon, effectively removing dirt without damaging the inner wall of the pipe. A force-bearing plate 43 is also fixed in the middle of the elastic support 41, and the force-bearing plate 43 is inclined relative to the length of the water distribution branch pipe 315. This design allows the water flow to more effectively push the wall-scraping cleaning component 4, ensuring its smooth sliding within the pipe.

[0043] During water distribution, water is alternately introduced through the first inlet pipe 312 and the second inlet pipe 313 to intermittently change the water flow direction within the water distribution branch pipe 315, thereby achieving reverse flushing of residual impurities within the water distribution branch pipe 315. Furthermore, during the water introduction process within the water distribution branch pipe 315, the water flow pushes the wall-scraping cleaning component 4 to slide within the water distribution branch pipe 315, causing the wall-scraping blades 42 to clean the inner wall of the water distribution branch pipe 315, scraping away contaminants from the inner wall, facilitating the flow of contaminants into the slag discharge pipe 34 under the impact of the incoming water.

[0044] Reference Figure 3Each water distribution main pipe 314 and water distribution branch pipe 315 has a first converging cylinder 5 fixed at its connection point. In this embodiment, the first converging cylinder 5 is located in the section of the water distribution branch pipe 315 near the end of the water distribution main pipe 314, and the cross-sectional area of ​​the first converging cylinder 5 gradually decreases in the direction away from the water distribution main pipe 314, which helps to increase the water flow velocity and improve the cleaning effect. In this embodiment, two first converging cylinders 5 are provided in one water distribution branch pipe 315. A second converging cylinder 6 is also fixed in the middle of the water distribution branch pipe 315. The second converging cylinder 6 includes a narrow cylindrical section 61 and an expanding cylindrical section 62 disposed at both ends of the narrow cylindrical section 61. The cross-sectional area of ​​the expanding cylindrical section 62 gradually decreases in the direction close to the narrow cylindrical section 61. The wall scraping cleaning component 4 is located between the first converging cylinder 5 and the second converging cylinder 6. When the water flow passes through and forms a vortex effect, it helps to push the wall scraping cleaning component 4 to move, further enhancing the cleaning force.

[0045] Reference Figure 1 and Figure 2 To further improve the reliability and stability of the system, a temperature control component 7 is added. The temperature control component 7 includes an underground heat collection pipe 71, a geothermal pump 72, and an in-pool heat exchange pipe assembly 73. The underground heat collection pipe 71 is located below the in-pool heat exchange pipe assembly 73 and is deeply buried underground in a serpentine pattern. The in-pool heat exchange pipe assembly 73 includes heat exchange pipes 731 and heat exchange jackets 732. Multiple heat exchange pipes 731 are spaced apart along the height of the infiltration tank 2, and each heat exchange pipe 731 is arranged in a serpentine pattern. Multiple heat exchange jackets 732 are provided, and each heat exchange jacket 732 corresponds to a water distribution branch pipe 315. The heat exchange jacket 732 is cylindrical and fits over the corresponding water distribution branch pipe 315. The heat exchange jacket 732 is also provided with clearance holes 7321 corresponding to the water distribution holes 3151. One end of the underground heat collector pipe 71 is connected to the geothermal pump 72, and the other end is connected to the heat exchange pipe 731 and heat exchange jacket 732 in the pool. The end of the heat exchange pipe 731 and heat exchange jacket 732 away from the underground heat collector pipe 71 is connected to the geothermal pump 72. When the geothermal pump 72 is started, it can drive the heat exchange medium in the underground heat collector pipe 71 to move into the heat exchange pipe group 73 in the pool, so as to realize the circulation heat exchange.

[0046] An insulation layer 25 is also fixed on the inner wall of the infiltration tank 2, which can reduce heat loss and maintain the normal operation of the system.

[0047] The implementation principle of this embodiment is as follows: During water distribution, the first and second inlet pipes 312 and 313 are controlled by the first and second shut-off valves to alternately supply water, thereby intermittently changing the water flow direction within the distribution branch pipe 315; thus achieving reverse flushing of residual impurities within the distribution branch pipe 315. When water is supplied through the first inlet pipe 312, the on / off element 35 near the first inlet pipe 312 is in a closed state, and the on / off element 35 near the second inlet pipe 313 is in an open state; when water is supplied through the second inlet pipe 313, the on / off element 35 near the second inlet pipe 313 is in a closed state. The on / off element 35 near the first inlet pipe 312 is in an open state. This design prevents wastewater from being directly discharged through the slag discharge pipe 34 connected to the main water distribution pipe 314 during water intake. Instead, the wastewater flows along one side of the water distribution pipe to the branch water distribution pipe 315 for distribution before flowing back into the main water distribution pipe 314 on the other side. This pushes impurities towards the other side of the main water distribution pipe 314, where they are then discharged through the corresponding slag discharge pipe 34. During water intake in the branch water distribution pipe 315, the water flow causes the wall-scraping cleaning component 4 to slide within the branch water distribution pipe 315, driving the wall-scraping blades 42 to clean the inner wall of the branch water distribution pipe 315, scraping away contaminants. This allows the contaminants to flow into the slag discharge pipe 34 under the impact of the incoming water. This method not only reduces the wear and corrosion problems caused by traditional cleaning brushes and their driving mechanisms but also significantly reduces the difficulty and cost of subsequent maintenance.

[0048] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A multi-household combined domestic sewage treatment system, characterized in that, include: The pretreatment unit (1) includes a grid channel (11), a grit chamber (12) and an equalization tank (13) connected in sequence. The infiltration pond (2) is connected to the regulating pond (13). The infiltration pond (2) includes a planting topsoil layer (21), a water distribution layer (22), an infiltration layer (23), and a soil treatment layer (24) arranged from top to bottom. The water distribution assembly (3) includes a water distribution network (31) and a drive source (36). The water distribution network (31) includes a main water inlet pipe (311), a first water inlet pipe (312), a second water inlet pipe (313), a main water distribution pipe (314), and a branch water distribution pipe (315). The main water inlet pipe (311) is connected to both the first water inlet pipe (312) and the second water inlet pipe (313). A first interceptor (32) is provided on the first water inlet pipe (312), and a second interceptor (33) is provided on the second water inlet pipe (313). The main water distribution pipe (314) and the branch water distribution pipe (315) are located within the water distribution layer (22). Two main water distribution pipes (314) are spaced apart. The first water inlet pipe (312) is connected to one of the main water distribution pipes (314), and the second water inlet pipe (314) is connected to the branch water distribution pipe (315). 13) Connected to another main water distribution pipe (314), the bottom of the main water distribution pipe (314) is connected to a slag discharge pipe (34), and a switch (35) is provided at the connection between the main water distribution pipe (314) and the slag discharge pipe (34). The switch (35) is used to control the opening and closing of the main water distribution pipe (314) and the slag discharge pipe (34); multiple water distribution branch pipes (315) are provided at intervals between the two main water distribution pipes (314); one end of the water distribution branch pipe (315) is connected to one main water distribution pipe (314), and the other end is connected to another main water distribution pipe (314). Multiple water distribution holes (3151) are opened on each water distribution branch pipe (315). The driving source (36) is used to drive the water in the regulating tank (13) to flow into the inlet main pipe (311). The wall-scraping cleaning component (4) is slidably disposed inside the water distribution branch pipe (315), including an elastic support (41) and a wall-scraping blade (42) disposed around the elastic support (41), the wall-scraping blade (42) abutting against the inner wall of the water distribution branch pipe (315).

2. The multi-household combined domestic sewage treatment system according to claim 1, characterized in that, A first concentrator (5) is provided at the connection between the main water distribution pipe (314) and the branch water distribution pipe (315), and the cross-sectional area of ​​the first concentrator (5) gradually decreases toward the branch water distribution pipe (315).

3. A multi-household combined domestic sewage treatment system according to claim 2, characterized in that, The water distribution branch pipe (315) is also provided with a second flow-gathering cylinder (6), which includes a narrow cylinder section (61) and an expansion cylinder section (62) provided at both ends of the narrow cylinder section (61). The cross-sectional area of ​​the expansion cylinder section (62) gradually decreases in the direction close to the narrow cylinder section (61). The wall-scraping cleaning component (4) is provided between the first flow-collecting cylinder (5) and the second flow-collecting cylinder (6).

4. A multi-household combined domestic sewage treatment system according to claim 2, characterized in that, A force-bearing plate (43) is also fixed on the elastic support (41), and the force-bearing plate (43) is inclined relative to the length direction of the water distribution branch pipe (315).

5. A multi-household combined domestic sewage treatment system according to claim 1, characterized in that, The permeation layer (23) includes a sand and gravel filter layer (231), a main permeation layer (232), and a fine sand buffer layer (233).

6. A multi-household combined domestic sewage treatment system according to claim 1, characterized in that, It also includes a temperature control component (7), which includes an underground heat collection pipe (71), a geothermal pump (72), and a heat exchange tube group (73) in the pool. The underground heat collection pipe (71) is located below the heat exchange tube group (73) in the pool and is connected to the heat exchange tube group (73) in the pool. The heat exchange tube group (73) in the pool is located in the infiltration pool (2). The geothermal pump (72) is used to drive the heat exchange medium in the underground heat collection pipe (71) to move into the heat exchange tube group (73) in the pool.

7. A multi-household combined domestic sewage treatment system according to claim 6, characterized in that, The heat exchange tube assembly (73) in the pool includes a heat exchange tube (731) and a heat exchange jacket (732). The heat exchange jacket (732) is sleeved outside the water distribution branch pipe (315), and the heat exchange jacket (732) is also provided with a clearance hole (7321) corresponding to the water distribution hole (3151).

8. A multi-household combined domestic sewage treatment system according to claim 6, characterized in that, An insulation layer (25) is provided on the inner wall of the infiltration tank (2).

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