CN107162353B

CN107162353B - Multistage river sewage treatment system and method

Info

Publication number: CN107162353B
Application number: CN201710605616.5A
Authority: CN
Inventors: 李华
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-07-24
Filing date: 2017-07-24
Publication date: 2020-09-08
Anticipated expiration: 2037-07-24
Also published as: CN107162353A

Abstract

The invention discloses a multistage river sewage treatment system and a method, comprising a base, a cylinder and a top cover which are connected in sequence; the interior of the barrel is sequentially divided into a facultative treatment cavity, an aerobic treatment cavity and a sedimentation cavity from top to bottom along the axial direction through a first partition plate and a second partition plate, and the facultative treatment cavity, the aerobic treatment cavity and the sedimentation cavity are sequentially communicated; the barrel is also provided with a water inlet pipe and a water outlet pipe, the water inlet pipe is used for guiding river water into the facultative treatment cavity, and the water outlet pipe is used for discharging purified water in the sedimentation cavity. Multistage river course sewage treatment system is the comprehensive sewage treatment device that an integration is convenient for remove, the storage of being convenient for, transportation and management, only need drop into one or more above-mentioned sewage treatment device during the use in pending river water region, through facultative aerobe, aerobic biotechnology handles, and deposit multistage integrated treatment, obtain the purified water and be fountain form blowout, can promote regional water circulation flow again, the fine purifying effect of performance, be favorable to reduce cost, guarantee city river course quality of water improves.

Description

Multistage river sewage treatment system and method

Technical Field

The invention relates to the technical field of sewage treatment, in particular to a multistage river sewage treatment system and method.

Background

Along with the development of cities, people are more and more concentrated, river channels of many cities are polluted by domestic sewage, and due to the fact that the mobility of an urban river network is small, river channels and water systems are not communicated, particularly, the river bed is improved, the water blocking bottleneck is led out, the river channel siltation is serious, the self-cleaning capacity of the water body is weak, and the restoration is difficult only through methods of planting floating bed plants through an ecological system and the like. At present, a treatment method for river pollution in large and medium-sized cities is generally to build a treatment system on the river side, and animals and plants cannot survive due to the serious degree of sewage in urban river channels, so that only after the urban river channels are polluted to a certain degree, the river water is lifted to the system for treatment and then is discharged back to the river channels. The method for treating the river sewage not only occupies land and has high construction cost, but also has low treatment efficiency and is particularly remarkable when purifying the whole river basin because the river sewage needs to be pumped into the sewage treatment system by a pump through a water pipe and then discharged into the river after being treated by the pump during sewage treatment. The method of pumping the sewage into the sewage treatment plant by the pump not only causes difficulty in pipeline laying because the sewage treatment plant is far away from a river channel, but also has high energy consumption, and the polluted urban inland river cannot be effectively treated because some small and medium-sized cities or counties do not have the sewage treatment plants.

Disclosure of Invention

The invention aims to solve the technical problems that the existing sewage treatment system constructed on the edge of an urban river has high construction difficulty and cost, low treatment efficiency and secondary pollution, and aims to provide a multi-stage river sewage treatment system and a method.

The invention is realized by the following technical scheme:

the multi-stage riverway sewage treatment system comprises a base, a cylinder and a top cover which are connected in sequence; the interior of the barrel is sequentially divided into a facultative treatment cavity, an aerobic treatment cavity and a sedimentation cavity from top to bottom along the axial direction through a first partition plate and a second partition plate, the facultative treatment cavity, the aerobic treatment cavity and the sedimentation cavity are sequentially communicated, and a flocculating agent is arranged in the sedimentation cavity; still be equipped with inlet tube and drain pipe on the barrel, the inlet tube is used for leading-in facultative anaerobic treatment chamber with river, the drain pipe is used for the discharge of the water purification of settling the intracavity.

The whole sewage treatment equipment is arranged into a cylinder structure, so that the balance of the sewage treatment equipment under the action of water flow is facilitated, and the relatively stable arrangement of the whole structure in a water body can be ensured due to the small river mobility of the urban river; and overall structure is convenient for save, transportation and management, only need during the use drop into one or more above-mentioned sewage treatment device and treat in the river water region, through facultative, aerobic biotechnology handles and deposit multistage integrated treatment, obtains the purified water and is fountain form blowout, can promote regional water circulation flow again, plays good purifying effect, is favorable to reduce cost, ensures that city river course quality of water improves.

Preferably, an overflow pipe is arranged in the facultative treatment cavity, one axial end of the overflow pipe penetrates through the first partition plate to be communicated with the aerobic treatment cavity, and the contact surface of the overflow pipe and the first partition plate is fixed in a sealing mode.

The facultative treatment cavity is used as a primary treatment section and plays a main role in purifying river water; the overflow pipe is arranged to increase the retention time of the river water to be treated in the facultative treatment cavity and ensure the full contact and the full reaction of macromolecular organic matters in the river water and the facultative biological filler; the purified river water flows into the aerobic treatment cavity through the overflow pipe for further treatment.

Preferably, an open slot is formed in the second partition plate, a baffle plate is connected to the open slot and located in the sedimentation chamber, and the aerobic treatment chamber and the sedimentation chamber are communicated with each other through a channel in the open slot and the baffle plate in sequence.

The aerobic treatment cavity is communicated with the sedimentation cavity mainly through the baffle plate channel, and when river water further treated by the aerobic treatment cavity flows through the baffle plate, the flow speed is reduced due to the change of the flow direction, so that the sedimentation of impurities in water is promoted, and the situation that the river water subjected to sedimentation separation in the sedimentation cavity is greatly impacted to influence the purification quality of finally discharged water can be prevented.

Preferably, the baffle comprises three baffles connected end to end in sequence, and the included angles between the plane where the three baffles are located and the horizontal line are α =45 °, β =20 °, and γ =70 ° in sequence along the water flow direction.

Through the inclination that sets up each baffle, can ensure that the river has sufficient dwell time and promote the sediment of aquatic impurity in the aerobic treatment intracavity, still need ensure rivers simultaneously smoothly, prevent at baffling board department rivers undersize, reduce purification efficiency.

Preferably, the inner side walls of the facultative treatment cavity and the aerobic treatment cavity are respectively provided with a net basket, the net basket of the facultative treatment cavity is filled with facultative biological filler, and the net basket of the aerobic treatment cavity is filled with aerobic biological filler; the side wall of the aerobic treatment cavity is also provided with an aeration pipe, and the aeration pipe is used for introducing air above the water surface of the river into the aerobic treatment cavity through a blower; the air outlet end of the aeration pipe is positioned below the net basket and is provided with a microporous aerator; and an exhaust pipe is arranged at the top of the cylinder and is used for communicating the upper space of the liquid level in the facultative treatment cavity with the atmospheric environment at the upper part of the water surface of the river channel.

The aeration pipe and the microporous aerator are mainly used for ensuring that sufficient oxygen is provided for the further purification treatment of the river water containing small molecular impurities in the aerobic treatment cavity; the facultative biological filler and the aerobic biological filler are arranged in the net basket, so that the facultative biological filler and the aerobic biological filler can be fully contacted with river water and expand in volume, the macromolecular organic matters and the biomembrane can be fully reacted, a certain vulcanization state is formed, and meanwhile, the facultative biological filler and the aerobic biological filler are limited in the space of the net basket, the overflow pipe is guaranteed to smoothly drain water, and the replacement and treatment are convenient. Meanwhile, the exhaust pipe is arranged for discharging waste gas generated by the facultative biological filler during sewage treatment, and is also used for discharging redundant air in the aerobic treatment cavity.

Preferably, set up two at least inlet tubes on the barrel the end of intaking of inlet tube is located the bottom of barrel, and a plurality of inlet tubes evenly distributed is on the lateral wall of barrel.

Because the river water at the bottom of the river channel is low in oxygen content and high in pollutants, the water inlet end of the water inlet pipe is arranged at the bottom of the cylinder body and is mainly used for extracting the river water at the bottom of the river channel for purification, and the sufficient purification treatment of the river channel sewage is guaranteed; meanwhile, water at the bottom of the river channel is extracted for purification, and the purified water is sprayed out from the surface of the river, so that a vertical circulating flow process is favorably formed, the exchange of a surface water body and a bottom water body is promoted, the micro-ecological environment is improved, the self-purification capacity of the water body is enhanced, and the water quality is improved in a short period. Meanwhile, a plurality of water purifying pipes are distributed along the circumferential direction of the cylinder body, and water can be purified, so that strong stirring effect can be formed on river water intercepted by the overflow pipe in the facultative treatment cavity, the river water can fully react with the facultative biomembrane, and finally the river water is discharged through the overflow pipe.

Preferably, the drain pipe comprises a main pipe and a branch pipe, and the main pipe is communicated with the branch pipe through the multi-way pipeline distributor; the branch pipe sequentially passes through the second partition plate, the first partition plate and the top of the cylinder body and extends out of the geometric center of the top cover; the top cap is the hemisphere casing, the lateral pipe stretches for the basic point along the geometric centre of top cap and is radial distribution and locate on the top cap, and all is equipped with the shower nozzle on the lateral pipe that is located on the top cap.

Through setting up the person in charge and the lateral pipe drain pipe reaches, set up the radial distribution of lateral pipe on the top cap, the purified water is the fountain form and gushes out, can promote purified water and air fully to contact, promotes dissolved oxygen volume, still can form the view simultaneously, and the pedestrian in the river course both sides of being convenient for is vwatched.

Preferably, the base is an inflatable floating mat, and an inflating nozzle of the inflatable floating mat is connected to the aeration pipe in a bypass mode through an inflating pipe.

The base is designed into the inflatable floating cushion, when the sewage treatment barrel integral equipment needs to be moved, only the inflatable floating cushion needs to be inflated, the gravity of the integral equipment structure of the barrel is balanced by utilizing the buoyancy effect of the inflatable floating cushion, and the whole sewage treatment equipment system is convenient for workers to move.

Preferably, the sewage treatment system further comprises a control system, the control system comprises a liquid level sensor and a control terminal, and the liquid level sensor is used for detecting liquid level information in the facultative treatment cavity, the aerobic treatment cavity and the sedimentation cavity in real time and transmitting the liquid level information to the control terminal; the control terminal is used for controlling the operation of the motor and the valve on the water inlet pipe and the operation of the motor and the valve on the aeration pipe according to the liquid level heights in the facultative treatment cavity and the aerobic treatment cavity; the control terminal controls the operation of a motor and a valve on the exhaust pipe according to the liquid level height in the sedimentation cavity; the control terminal is also used for controlling the operation of the valve on the inflation tube and the operation of the exhaust valve of the inflatable floating cushion.

The sewage treatment method based on the multistage river sewage treatment system comprises the following steps:

step A, placing a cylinder body provided with a base in river water to be treated, and ensuring that a top cover is positioned above the river water surface;

step B, water inlet: introducing river wastewater into the facultative treatment cavity through a water inlet pipe;

step C, facultative treatment: the river water in the river channel is fully contacted with the facultative biological filler, macromolecular organic matters in the river water are decomposed into easily biochemical micromolecular organic matters, and waste gas is discharged through an exhaust pipe;

step D, aerobic treatment: river water treated by the facultative treatment cavity enters the aerobic treatment cavity through the overflow pipe, and is treated by aerobic biological fillers under the aeration action of the aeration pipe, so that residual pollutants are further removed;

step E, precipitation: the river water treated by the aerobic treatment cavity flows into the sedimentation cavity through the open slot and the baffle plate for sedimentation;

step F, draining: the upper part purified water in the sedimentation cavity is sprayed out from the upper part of the top cover through the main pipe, the branch pipe and the spray head in sequence.

Compared with the prior art, the invention has the following advantages and beneficial effects:

the invention provides a multistage river sewage treatment system and a multistage river sewage treatment method, wherein the whole sewage treatment equipment is set into a cylinder structure, which is favorable for balancing the action of water flow; the integral structure is convenient for storage, transportation and management, when in use, only one or more sewage treatment devices are needed to be put into a river water area to be treated, and purified water is sprayed out in a fountain shape through facultative, aerobic biotechnology treatment and multi-stage sedimentation comprehensive treatment, so that the circulating flow of the water body in the area can be promoted, a good purification effect is achieved, the cost is reduced, and the improvement of the water quality of the urban river is guaranteed; because the river water at the bottom of the river channel is low in oxygen content and high in pollutants, the water inlet end of the water inlet pipe is arranged at the bottom of the cylinder body and is mainly used for extracting the river water at the bottom of the river channel for purification, and the sufficient purification treatment of the river channel sewage is guaranteed; meanwhile, water at the bottom of the river channel is extracted for purification, and the purified water is sprayed out from the surface of the river, so that a vertical circulating flow process is favorably formed, the exchange of a surface water body and a bottom water body is promoted, the micro-ecological environment is improved, the self-purification capacity of the water body is enhanced, and the water quality is improved in a short period. Meanwhile, a plurality of water purifying pipes are distributed along the circumferential direction of the cylinder body, and water can be purified, so that strong stirring effect can be formed on river water intercepted by the overflow pipe in the facultative treatment cavity, the river water can fully react with the facultative biomembrane, and finally the river water is discharged through the overflow pipe.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:

FIG. 1 is a schematic view of the overall structure of a multi-stage river sewage treatment system according to the present invention;

FIG. 2 is a schematic cross-sectional view of the barrel of the present invention;

FIG. 3 is a schematic top view of the top cover of the present invention;

FIG. 4 is a schematic view of a partial cross-sectional structure of a baffle according to the present invention.

Reference numbers and corresponding part names in the drawings: 1-base, 2-barrel, 21-first clapboard, 22-second clapboard, 23-facultative treatment cavity, 24-aerobic treatment cavity, 25-sedimentation cavity, 26-baffle plate, 27-net basket, 28-sludge discharge pipe, 3-top cover, 4-water inlet pipe, 5-water outlet pipe, 51-main pipe, 52-branch pipe, 53-multi-way pipeline distributor, 54-spray head, 6-overflow pipe, 7-aeration pipe, 8-exhaust pipe.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples and accompanying drawings, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not meant to limit the present invention.

Example 1

As shown in fig. 1 to 4, the invention provides a multistage river sewage treatment system, which comprises a base 1, a cylinder 2 and a top cover 3 which are sequentially connected, wherein the cylinder 2 is of a cylindrical structure with a closed axial bottom end, the axial top end of the cylinder can be sealed by a detachably connected cover plate, and the top cover 3 is hermetically connected with the axial top end of the cylinder 2 through a flange. The interior of the cylinder body 2 is sequentially divided into a facultative treatment cavity 23, an aerobic treatment cavity 24 and a sedimentation cavity 25 from top to bottom along the axial direction by a first partition plate 21 and a second partition plate 22. The facultative treatment cavity 23, the aerobic treatment cavity 24 and the sedimentation cavity 25 are communicated in sequence, and a flocculating agent is put into the sedimentation cavity 25; the side wall of the cylinder body 2 is also provided with a water inlet pipe 4 and a water outlet pipe 5, the water inlet pipe 4 is used for guiding river water into the facultative treatment cavity 23, and the water outlet pipe 5 is used for discharging purified water in the sedimentation cavity 25.

Example 2

The improvement is further carried out on the basis of the embodiment 1, an overflow pipe 6 is arranged in the facultative treatment cavity 23, one axial end of the overflow pipe 6 penetrates through the first partition plate 21 to be communicated with the aerobic treatment cavity 24, and the contact surface of the overflow pipe 6 and the first partition plate 21 is fixed in a sealing mode through welding. The second partition board 22 is provided with a rectangular open slot, the open slot is integrally connected with a baffle board 26, the baffle board 26 is positioned in the sedimentation cavity 25, and the aerobic treatment cavity 24 and the sedimentation cavity 25 are communicated with each other through a channel on the open slot and the baffle board 26 in sequence. The baffle 26 comprises three baffles connected end to end in sequence, and along the water flow direction, the included angles between the plane where the three baffles are located and the horizontal line are α =45 °, β =20 °, and γ =70 ° in sequence.

Example 3

In addition to the improvement of the embodiment 2, the inner side walls of the facultative treatment cavity 23 and the aerobic treatment cavity 24 can be detachably connected with and provided with a net basket 27, and the net basket 27 of the facultative treatment cavity 23 is filled with the facultative biological filler. The net basket 27 of the aerobic treatment cavity 24 is filled with aerobic biological filler. The side wall of the aerobic treatment cavity 24 is also provided with an aeration pipe 7, and the aeration pipe 7 is used for introducing air above the water surface of the river into the aerobic treatment cavity 24 through a blower; the air outlet end of the aeration pipe 7 is positioned below the net basket 27 and is provided with a microporous aerator. The top of barrel 2 is equipped with blast pipe 8, and blast pipe 8 is used for communicateing facultative anaerobic treatment chamber 23 inner liquid level upper portion space and river course surface of water upper portion atmospheric environment.

Example 4

Further improve on embodiment 3's basis, set up to four inlet tube 4 on the barrel 2, the end of intaking of inlet tube 4 is located the bottom of barrel 2, and four inlet tube 4 evenly distributed are on the lateral wall of barrel 2.

Example 5

In a further improvement of embodiment 4, the water discharge pipe 5 includes a main pipe 51 and branch pipes 52, and the main pipe 51 is communicated with the eight branch pipes 52 through an eight-way pipeline distributor 53. The branch pipe 52 passes through the second partition 22, the first partition 21, and the top of the can 2 in this order, and extends out through the geometric center of the top cover 3. The top cover 3 is a hemispherical shell, the branch pipes 52 extend along the geometric center of the top cover 3 as a base point and are radially distributed on the top cover 3, and the spray heads 54 are arranged on the branch pipes 52 on the top cover 3.

Example 6

The improved structure is further improved on the basis of the embodiment 5, the base 1 is an inflatable floating mat, and an inflating nozzle of the inflatable floating mat is connected to an aeration pipe 7 through an inflating pipe in a bypass mode.

Example 7

The sewage treatment system is further improved on the basis of the embodiment 6, and the sewage treatment system also comprises a control system for controlling the whole sewage treatment system to normally operate, so that the situation that redundant air in the aerobic treatment cavity cannot be smoothly discharged is prevented, and the continuous sewage treatment is ensured; meanwhile, the remote switch control is facilitated, and the movement and management are facilitated. The control system comprises a liquid level sensor and a control terminal, wherein the liquid level sensor is used for detecting liquid level information in the facultative treatment cavity 23, the aerobic treatment cavity 24 and the sedimentation cavity 25 in real time and transmitting the liquid level information to the control terminal; the control terminal is used for controlling the operation of the motor and the valve on the water inlet pipe 4 and the operation of the motor and the valve on the aeration pipe 7 according to the liquid level heights in the facultative treatment cavity 23 and the aerobic treatment cavity 24; the control terminal controls the operation of the motor and the valve on the exhaust pipe 8 according to the liquid level height in the sedimentation cavity 25; the control terminal is also used for controlling the operation of the valve on the inflation tube and the operation of the exhaust valve of the inflatable floating cushion.

Example 8

The sewage treatment method of the multistage river sewage treatment system based on the embodiment 7 comprises the following specific steps:

step A, placing a cylinder body 2 provided with a base 1 in river water to be treated, and ensuring that a top cover 3 is positioned above the river water surface;

step B, water inlet: river wastewater is guided into the facultative treatment cavity 23 through the water inlet pipe 4;

step C, facultative treatment: river water in the river channel is fully contacted with the facultative biological filler, macromolecular organic matters in the river water are decomposed into easily biochemical micromolecular organic matters, and waste gas is discharged through the exhaust pipe 8;

step D, aerobic treatment: river water treated by the facultative treatment cavity 23 enters the aerobic treatment cavity 24 through the overflow pipe 6, and is further removed with residual pollutants through aerobic biological filler treatment under the aeration action of the aeration pipe 7;

step E, precipitation: the river water treated by the aerobic treatment cavity 24 flows into the sedimentation cavity 25 through the open slot and the baffle plate 26 for sedimentation;

step F, draining: the upper purified water in the sedimentation chamber 25 is discharged from the upper part of the top cover 3 through the main pipe 51, the branch pipe 52 and the shower head 54 in this order.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. The multi-stage riverway sewage treatment system is characterized by comprising a base (1), a cylinder body (2) and a top cover (3) which are connected in sequence; the interior of the barrel body (2) is sequentially divided into a facultative treatment cavity (23), an aerobic treatment cavity (24) and a sedimentation cavity (25) from top to bottom through a first partition plate (21) and a second partition plate (22) along the axial direction, the facultative treatment cavity (23), the aerobic treatment cavity (24) and the sedimentation cavity (25) are sequentially communicated, and a flocculating agent is arranged in the sedimentation cavity (25); the barrel (2) is also provided with a water inlet pipe (4) and a water outlet pipe (5), the water inlet pipe (4) is used for guiding river water into the facultative treatment cavity (23), and the water outlet pipe (5) is used for discharging purified water in the sedimentation cavity (25);

the barrel (2) is provided with at least two water inlet pipes (4), the water inlet ends of the water inlet pipes (4) are positioned at the bottom of the barrel (2), and the water inlet pipes (4) are uniformly distributed on the side wall of the barrel (2); the water discharge pipe (5) comprises a main pipe (51) and branch pipes (52), and the main pipe (51) is communicated with the branch pipes (52) through a multi-way pipeline distributor (53); the branch pipe (52) sequentially passes through the second partition plate (22), the first partition plate (21) and the top of the barrel (2) and extends out of the geometric center of the top cover (3); the top cover (3) is a hemispherical shell, the branch pipes (52) extend along the geometric center of the top cover (3) as a base point and are radially distributed on the top cover (3), and the branch pipes (52) on the top cover (3) are provided with spray heads (54);

an overflow pipe (6) is arranged in the facultative treatment cavity (23), one axial end of the overflow pipe (6) penetrates through the first partition plate (21) to be communicated with the aerobic treatment cavity (24), and the overflow pipe (6) is fixed with the contact surface of the first partition plate (21) in a sealing manner;

the base (1) is an inflatable floating mat.

2. The multistage riverway sewage treatment system according to claim 1, wherein the second partition plate (22) is provided with an open slot, the open slot is connected with a baffle plate (26), the baffle plate (26) is positioned in the sedimentation chamber (25), and the aerobic treatment chamber (24) and the sedimentation chamber (25) are communicated with each other through a channel on the open slot and the baffle plate (26) in sequence.

3. The multistage riverway sewage treatment system according to claim 2, wherein the baffle plate (26) comprises three baffle plates which are sequentially connected end to end, and the included angles between the plane of the three baffle plates and the horizontal line are sequentially alpha =45 °, beta =20 ° and gamma =70 ° along the water flow direction.

4. The multi-stage riverway sewage treatment system according to claim 1, wherein the facultative treatment chamber (23) and the aerobic treatment chamber (24) are provided with mesh baskets (27) on the inner side walls, the mesh baskets (27) of the facultative treatment chamber (23) are filled with facultative biological filler, and the mesh baskets (27) of the aerobic treatment chamber (24) are filled with aerobic biological filler; an aeration pipe (7) is further arranged on the side wall of the aerobic treatment cavity (24), and the aeration pipe (7) is used for introducing air above the water surface of the river into the aerobic treatment cavity (24) through a blower; the air outlet end of the aeration pipe (7) is positioned below the net basket (27) and is provided with a microporous aerator; the top of barrel (2) is equipped with blast pipe (8), blast pipe (8) are used for communicateing liquid level upper portion space and river course surface of water upper portion atmospheric environment in facultative treatment chamber (23).

5. The multi-stage riverway sewage treatment system according to claim 4, wherein the base (1) is an inflatable floating mat, and an inflation nozzle of the inflatable floating mat is connected to the aeration pipe (7) in a bypass mode through an inflation pipe.

6. The multi-stage riverway sewage treatment system according to claim 5, further comprising a control system, wherein the control system comprises a liquid level sensor and a control terminal, and the liquid level sensor is used for detecting liquid level information in the facultative treatment chamber (23), the aerobic treatment chamber (24) and the sedimentation chamber (25) in real time and transmitting the liquid level information to the control terminal; the control terminal is used for controlling the operation of the motor and the valve on the water inlet pipe (4) and the operation of the motor and the valve on the aeration pipe (7) according to the liquid level heights in the facultative treatment cavity (23) and the aerobic treatment cavity (24); the control terminal controls the operation of a motor and a valve on the exhaust pipe (8) according to the liquid level height in the sedimentation cavity (25); the control terminal is also used for controlling the operation of the valve on the inflation tube and the operation of the exhaust valve of the inflatable floating cushion.

7. The sewage treatment method of the multistage riverway sewage treatment system according to any one of claims 1 to 6, which comprises the following steps:

step A, placing a cylinder (2) provided with a base (1) in river water to be treated, and ensuring that a top cover (3) is positioned above the river water surface;

step B, water inlet: river wastewater is led into the facultative treatment cavity (23) through the water inlet pipe (4);

step C, facultative treatment: river water in the river channel is fully contacted with the facultative biological filler, macromolecular organic matters in the river water are decomposed into easily biochemical micromolecular organic matters, and waste gas is discharged through an exhaust pipe (8);

step D, aerobic treatment: river water treated by the facultative treatment cavity (23) enters the aerobic treatment cavity (24) through the overflow pipe (6), and is further removed by aerobic biological filler treatment under the aeration action of the aeration pipe (7);

step E, precipitation: river water treated by the aerobic treatment cavity (24) flows into the sedimentation cavity (25) through the open slot and the baffle plate (26) for sedimentation;

step F, draining: purified water at the upper part in the sedimentation cavity (25) is sprayed out from the upper part of the top cover (3) through the main pipe (51), the branch pipe (52) and the spray head (54) in sequence.