Sewage treatment system as well as treatment method and application thereof

Abstract

The invention provides a sewage treatment system as well as a treatment method and application thereof. The system comprises a baffling type front tank, a circulating type aeration tank, an intermediate sedimentation tank and a deep treatment tank which are connected in sequence, the baffling type front pool is used for intercepting and decomposing sewage, so that sludge in the sewage is intercepted in the reaction pool, macromolecular organic matters in the sewage are decomposed into micromolecular organic matters, and insoluble organic matters are converted into soluble organic matters; the circulating aeration tank is used for carrying out aeration and flow pushing on the sewage and enabling the sewage to circularly flow so as to generate a treatment effect of an oxidation ditch process; the intermediate settling pond is used for settling sewage, and clear water after settling is discharged into the deep treatment pond; one part of the settled sludge flows back to the baffling type front pool, and the other part of the settled sludge enters a sludge treatment pool to be treated; and the deep treatment tank is used for sequentially carrying out oxidation, adsorption, absorption, precipitation and filtration treatment on the sewage and then discharging the sewage, and discharging or recycling the sewage after reaching the standard.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and in particular relates to a sewage treatment system and a treatment method and application thereof. Background Art

[0002] Urban sewage is mainly mixed sewage. Mixed sewage includes industrial sewage discharged during the production of dyes, medicines, pesticide intermediates and other chemical products. Mixed sewage has the characteristics of complex water quality, deep color, high acidity and high content of organic toxic substances.

[0003] It is difficult to achieve the requirements of high efficiency, energy saving, low cost and environmental protection by using traditional physical, chemical and biochemical treatment processes to treat mixed sewage. Therefore, the research and development of new combined processes based on improved or innovative traditional physical, chemical and biochemical treatment processes has become a hot topic in the research of urban mixed sewage treatment technology. Summary of the invention

[0004] The technical problem to be solved by the present invention is: the present invention provides a sewage treatment system with simple operation and low investment, which collects and treats urban mixed sewage so that it can be discharged or reused in compliance with standards.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] The first aspect of the present invention provides a sewage treatment system, which includes a baffled pre-tank, a circulating aeration tank, an intermediate sedimentation tank and a deep treatment tank connected in sequence; the baffled pre-tank is used to intercept and decompose the sewage entering the treatment system, so that the sludge in the sewage is intercepted in the reaction tank, and the macromolecular organic matter in the sewage is decomposed into small molecular organic matter, and the insoluble organic matter is converted into soluble organic matter; the circulating aeration tank is used to aerate and push the sewage treated by the baffled pre-tank and make the sewage circulate to produce the treatment effect of the oxidation ditch process; the intermediate sedimentation tank is used to precipitate the sewage treated by the circulating aeration tank, and the clear water after precipitation is discharged into the deep treatment tank; a part of the precipitated sludge is returned to the baffled pre-tank, and the other part enters the sludge treatment tank for treatment; the deep treatment tank is used to oxidize, adsorb and absorb, precipitate and filter the sewage treated by the intermediate sedimentation tank in sequence, and then discharge it, discharge it to meet the standards or reuse it.

[0007] Furthermore, the deep treatment pool includes an advanced oxidation chamber, an adsorption chamber, a filtration chamber arranged at the upper part, and a separation chamber arranged at the lower part; the advanced oxidation chamber is used to aerate the sewage so that the pollutants in the sewage are oxidized into substances that are easily absorbed and adsorbed, and the treated sewage is transported to the adsorption chamber; the adsorption chamber is used to adsorb and absorb the pollutants in the sewage, and transport the treated sewage to the separation chamber; the separation chamber is used to separate the sewage by gravity, and transport the separated sewage to the filtration chamber and discharge the bottom sediment; the filtration chamber is used to filter the sewage and then discharge it.

[0008] Furthermore, an ozone aeration plate is provided at the bottom of the advanced oxidation chamber, a water distribution pipe is provided below the ozone aeration plate, the water distribution pipe is connected to the water inlet pipe of the deepening treatment tank, and the water inlet pipe of the deepening treatment tank is connected to the drainage pipe of the intermediate sedimentation tank; the ozone aeration plate is connected to an ozone blower, and the ozone blower is connected to an ozone generator; the adsorption chamber is located outside the advanced oxidation chamber; an adsorption filler is provided inside the adsorption chamber; the filter chamber is located outside the adsorption chamber, filter material is provided inside the filter chamber, an overflow weir of the deepening treatment tank is provided on the upper part of the filter chamber, and the overflow weir of the deepening treatment tank is connected to the outlet pipe of the deepening treatment tank; a sediment discharge pipe is provided at the bottom of the separation chamber.

[0009] Furthermore, the adsorption filler is prepared by the following steps: S1, harvesting and drying reed straw; crushing the reed straw after drying and passing it through a 100-mesh sieve; S2, washing and drying the sieved reed straw, and then putting it into a tubular furnace, introducing nitrogen at a flow rate of 200 mL / min, heating at a rate of 20°C / min, setting the temperature to 800°C for a constant temperature time of 4 hours, and then cooling to room temperature to obtain reed straw charcoal; S3, immersing the reed straw charcoal in a hydrogen peroxide solution with a mass concentration of 4%, and heating at room temperature. Stir and soak at 80℃ for 2 hours, then filter and wash until neutral; S4, immerse the washed reed straw charcoal in 3mol / L hydrochloric acid, soak at 80℃ for 3 hours, then filter and wash until neutral; S5, immerse in 10% aluminum sulfate solution, stir at 80℃ for 30 minutes; filter and dry; S6, anaerobic cracking of the dried reed straw charcoal at 800℃ for 60 minutes; cool to room temperature; pass through a 100-mesh sieve to obtain the adsorption filler.

[0010] Furthermore, the baffled pre-tank comprises an anaerobic chamber, an anoxic chamber and an anaerobic chamber which are separated by an outer tank wall and a plurality of baffle walls and connected in sequence; the head end of the anaerobic chamber is provided with a baffled pre-tank water inlet for supplying sewage, and the end of the anaerobic chamber is provided with a baffled pre-tank water outlet; the upper parts of the anaerobic chamber, the anoxic chamber and the anaerobic chamber are all provided with an upper cover and a methane gas collecting and discharging pipe; the baffle wall is arranged vertically to the outer tank wall; wherein, the baffle wall is used to produce a blocking effect and cooperate with the sedimentation effect of the sludge itself to intercept the sludge in the reaction tank, so that the pollutants in the sewage are fully in contact with the microorganisms; the anaerobic chamber, the anoxic chamber and the anaerobic chamber are used to use facultative bacteria and heterotrophic bacteria to decompose the macromolecular organic matter in the sewage into small molecular organic matter and convert the insoluble organic matter into soluble organic matter.

[0011] Furthermore, the circulating aeration tank includes a neutral plate, a surface aerator, a drum aerator, a biochemical filler, an overflow plate and an interception grid; the neutral plate is arranged at the middle position of the circulating aeration tank; the surface aerator is arranged at both ends of the neutral plate, and the surface aerator is used to push the sewage in the circulating aeration tank to flow around the neutral plate; the drum aerator is arranged on one side of the neutral plate, and the drum aerator is provided with an aeration head and an air distribution pipe, and the air distribution pipe is connected to a blower; the biochemical filler is filled in the circulating aeration tank; the overflow plate is located at the end of the circulating aeration tank; the interception grid covers the upper part and the front end of the overflow plate, and is arranged parallel to the overflow plate.

[0012] Furthermore, the biochemical filler is made of polyethylene and is spherical in shape; the mesh size of the interception grid is smaller than the diameter of the biochemical filler.

[0013] Furthermore, the intermediate sedimentation tank is connected to the overflow plate; an overflow platform is provided at the tail of the intermediate sedimentation tank, and the outflow of the overflow platform is collected and discharged by the drainage pipe of the intermediate sedimentation tank; a sludge pump and a sludge discharge pipe are also provided at the bottom of the intermediate sedimentation tank.

[0014] The second aspect of the present invention provides a sewage treatment method, which uses the sewage treatment system as mentioned above, and the treatment method includes: the sewage enters the baffled pre-tank from the water inlet of the baffled pre-tank and then moves back and forth along the baffle wall, passing through the anaerobic chamber, the anoxic chamber and the anaerobic chamber in turn, the sludge in the reaction tank moves with the flow of sewage and the rising effect of biogas, the blocking effect of the baffle wall and the sedimentation effect of the sludge itself reduce the flow rate of the sludge, so that a large amount of sludge is trapped in the reaction tank, the microorganisms in the reaction tank are fully in contact with the pollutants in the sewage, the facultative bacteria in the anaerobic chamber, the heterotrophic bacteria in the anoxic chamber and the anaerobic chamber decompose the macromolecular organic matter in the sewage into small molecular organic matter, and convert the insoluble organic matter into soluble organic matter; the sewage then enters the circulating aeration tank, the surface aerator aerates the sewage on the one hand, and promotes the water flow to accelerate the flow on the other hand, the drum aerator strengthens the aeration of the sewage, the biochemical filler becomes the carrier of the activated sludge, the sewage circulates along the neutral plate, and produces The treatment effect of the oxidation ditch process is that the interception grid prevents the biochemical filler from flowing into the downstream; the sewage then enters the intermediate sedimentation tank through the overflow plate, and the clean water after sedimentation flows into the drainage pipe of the intermediate sedimentation tank through the overflow platform. Part of the precipitated sludge flows back to the baffled front tank through the sludge pump and the sludge discharge pipe, and part of it enters the sludge treatment tank for treatment; the sewage in the drainage pipe of the intermediate sedimentation tank enters the advanced oxidation chamber through the inlet pipe and water distribution pipe of the deepening treatment tank, and the ozone aeration disk produces a large number of fine bubbles, and the pollutants in the sewage are oxidized into substances that are easy to absorb and adsorb; then the water enters the adsorption chamber, and the adsorption filler adsorbs and absorbs the pollutants in the sewage; the water after adsorption enters the separation chamber, and the solids in the water sink under the action of gravity, and are discharged to through the sediment discharge pipe at the bottom, and enter the sludge treatment tank for treatment; then the sewage enters the filter chamber, the filter material filters the water, and the filtered water is discharged through the overflow weir of the deepening treatment tank and the outlet pipe of the deepening treatment tank, and is discharged or reused in compliance with the standards.

[0015] The second aspect of the present invention provides an application of the sewage treatment system as mentioned above in the field of urban sewage treatment, wherein the sewage is specifically mixed sewage composed of industrial sewage discharged during the production of dyes, medicines, pesticide intermediates and other chemical products; wherein the water quality indicators of the mixed sewage before treatment are COD 500 mg / L, BOD5350 mg / L, NH4-N45 mg / L, TN 70 mg / L, TP 8 mg / L, SS 350 mg / L; the water quality indicators after treatment are COD<50 mg / L, BOD5<10 mg / L, NH4-N<5(8) mg / L, TN<15 mg / L, TP<0.5 mg / L.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) The present invention has a simple structure and a low manufacturing cost; (2) The adsorption filler is prepared by using reed straw as raw material, which has a relatively good adsorption effect on mixed sewage; (3) The operation and management are simple and convenient; (4) The sewage is deeply treated and the effluent can be reused. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplifications do not constitute limitations on the embodiments. Unless otherwise stated, the pictures in the drawings do not constitute proportional limitations.

[0019] Figure 1 It is a structural schematic diagram of a specific embodiment of the present invention;

[0020] Figure 2 It is a longitudinal cross-sectional view of the advanced oxidation chamber of the present invention taken along line AA.

[0021] Figure 1 , Figure 2 Middle: 1 baffled pre-tank, 11 outer tank wall, 12 baffle wall, 13 facultative aerobic chamber, 14 anoxic chamber, 15 anaerobic chamber, 16 baffled pre-tank water inlet, 17 baffled pre-tank water outlet, 2 circulating aeration tank, 21 neutral plate, 22 surface aerator, 23 drum aerator, 24 biochemical filler, 25 overflow plate, 26 interception grid, 3 intermediate sedimentation tank, 31 overflow platform, 4 deep treatment tank, 41 advanced oxidation chamber, 411 ozone aeration disc, 412 water distribution pipe, 413 deep treatment tank water inlet pipe, 42 adsorption chamber, 421 adsorption filler, 43 filter chamber, 431 filter material, 432 deep treatment tank overflow weir, 44 separation chamber, 441 sediment discharge pipe. DETAILED DESCRIPTION

[0022] The present invention is described in detail below in conjunction with specific implementation modes.

[0023] like Figure 1 , Figure 2 As shown, a sewage treatment system includes: a baffled front tank 1, a circulating aeration tank 2, an intermediate sedimentation tank 3 and a deep treatment tank 4.

[0024] The baffled pre-tank 1 is located at the front end of the entire sewage treatment system and is a rectangular parallelepiped structure; the baffled pre-tank 1 includes an anaerobic chamber 13, an anoxic chamber 14 and an anaerobic chamber 15 which are separated by an outer tank wall 11 and a plurality of baffle walls 12; a baffled pre-tank water inlet 16 for supplying sewage is provided at the head end of the anaerobic chamber 13; the end of the anaerobic chamber 13 is communicated with the head end of the anoxic chamber 14; the end of the anoxic chamber 14 is communicated with the head end of the anaerobic chamber 15; a baffled pre-tank water outlet 17 is provided at the end of the anaerobic chamber 15; the upper parts of the anaerobic chamber 13, the anoxic chamber 14 and the anaerobic chamber 15 of the baffled pre-tank are all provided with an upper cover and a methane gas collecting and discharging pipe; the baffle wall 12 is made of sandless concrete and is vertically arranged with the outer tank wall 11.

[0025] The circulating aeration tank 2 is located at the rear end of the baffled front tank 1 and is connected to the baffled front tank outlet 17. The circulating aeration tank 2 is a rectangular structure; the circulating aeration tank includes a neutral plate 21, a surface aerator 22, a drum aerator 23, a biochemical filler 24, an overflow plate 25 and an interception screen 26.

[0026] The neutral plate 21 is located in the middle of the circulating aeration tank 2 , is made of a stainless steel plate, and is parallel to the outer tank wall 11 .

[0027] The surface aerator 22 is arranged at both ends of the neutral plate 21, and the rotating brush of the surface aerator 22 pushes the sewage in the circulating aeration tank 2 to flow around the neutral plate 21; the drum aerator 23 is installed on one side of the neutral plate 21, and the drum aerator 23 is provided with an aeration head and an air distribution pipe, and the air distribution pipe is connected to the blower outside the circulating aeration tank 2.

[0028] The biochemical filler 24 is filled in the circulating aeration tank 2, and the biochemical filler 24 meets the following requirements: ① The specific gravity is close to that of water, and its specific gravity is slightly less than 1 after biofilm formation, and it floats on the surface of the water when there is no aeration; ② After biofilm formation, it can be fluidized in water under normal aeration intensity; ③ The aged biofilm automatically falls off by hydraulic flushing and aeration stirring to ensure the activity of the biofilm; ④ It can be directly added to the water; ⑤ Its flow is guided by water flow; ⑥ It is made of polyethylene; ⑦ The shape of the biochemical filler is spherical.

[0029] The overflow plate 25 is located at the end of the circulating aeration tank 2 , is made of a stainless steel plate, and is vertically arranged with respect to the outer tank wall 11 .

[0030] The interception grid 26 is located at the upper part and front end of the overflow plate 25 , is arranged parallel to the overflow plate 25 , is made of metal, and the size of its mesh is slightly smaller than the diameter of the biochemical filler 24 .

[0031] The intermediate sedimentation tank 3 is located at the rear end of the circulating aeration tank 2 and connected to the overflow plate 25 of the circulating aeration tank 2. The intermediate sedimentation tank 3 is a rectangular parallelepiped structure. An overflow platform 31 is provided at the tail of the intermediate sedimentation tank 3, and the effluent of the overflow platform 31 is collected and discharged by the drainage pipe of the intermediate sedimentation tank 3. The overflow platform 31 is made of sandless concrete and is vertically arranged with the outer tank wall 11 of the intermediate sedimentation tank 3; a sludge pump and a sludge discharge pipe are provided at the bottom of the intermediate sedimentation tank 3.

[0032] The in-depth treatment tank 4 is located at the rear end of the intermediate sedimentation tank 3 ; the in-depth treatment tank 4 is provided with an advanced oxidation chamber 41 , an adsorption chamber 42 , a filtration chamber 43 and a separation chamber 44 .

[0033] The advanced oxidation chamber 41 is located at the center of the deep treatment tank 4. The advanced oxidation chamber 41 is provided with an ozone aeration plate 411. A water distribution pipe 412 is provided below the ozone aeration plate 411. The water distribution pipe 412 is a concentric circle or grid structure. The water distribution pipe 412 is connected to the deep treatment tank water inlet pipe 413. The deep treatment tank water inlet pipe 413 is connected to the middle sedimentation tank drainage pipe. The ozone aeration plate 411 is connected to the ozone fan outside the deep treatment tank through a pipeline, and the ozone fan is connected to the ozone generator through a pipeline.

[0034] The adsorption chamber 42 is located outside the advanced oxidation chamber 41 ; an adsorption filler 421 is provided inside the adsorption chamber 42 .

[0035] The manufacturing process of the adsorption filler 421 is as follows:

[0036] (1) harvesting and drying the reed straw; crushing the reed straw after drying and passing it through a 100-mesh sieve;

[0037] (2) washing and drying the sieved reed straw, placing it in a tubular furnace, introducing nitrogen at a flow rate of 200 mL / min, heating at a rate of 20 °C / min, setting the temperature to 800 °C for a constant temperature time of 4 h, and then cooling it to room temperature to obtain reed straw charcoal;

[0038] (3) immersing the reed straw charcoal in a hydrogen peroxide solution with a mass concentration of 4%, stirring and soaking at a temperature of 80° C. for 2 hours, and then filtering and washing until neutral;

[0039] (4) immersing the washed reed straw charcoal in 3 mol / L hydrochloric acid at 80°C for 3 hours, then filtering and washing until neutral;

[0040] (5) immersing the mixture in a 10% aluminum sulfate solution, stirring the mixture at 80° C. for 30 minutes, filtering the mixture, and drying the mixture;

[0041] (6) The dried reed straw charcoal is anaerobicly cracked at 800° C. for 60 minutes; cooled to room temperature; and sieved through a 100-mesh sieve to obtain an adsorption filler.

[0042] The filter chamber 43 is located outside the adsorption chamber 42, and a filter material 431 is arranged in the filter chamber. A deepening treatment pool overflow weir 432 is arranged on the upper part of the filter material 431. The deepening treatment pool overflow weir 432 is connected to the deepening treatment pool outlet pipe, and the water discharged from the deepening treatment pool outlet pipe meets the standards for discharge or reuse. The filter material 431 is gravel or sand.

[0043] The separation chamber 44 is located at the lower part of the deep treatment tank 4 , and a sediment discharge pipe 441 is provided at the bottom of the separation chamber 44 .

[0044] The process of treating sewage in the sewage treatment system is as follows:

[0045] ① After the mixed sewage enters the baffled pre-tank from the baffled pre-tank water inlet 16, it moves back and forth along the baffle wall 12, and passes through the facultative anaerobic chamber 13, the anoxic chamber 14 and the anaerobic chamber 15 in turn. The sludge in the reaction tank moves with the flow of sewage and the rising effect of biogas. The blocking effect of the baffle wall 12 and the sedimentation effect of the sludge itself reduce the flow rate of the sludge. Therefore, a large amount of sludge is retained in the reaction tank. The microorganisms in the reaction tank are in full contact with the pollutants in the sewage. The facultative bacteria in the facultative anaerobic chamber 13 and the heterotrophic bacteria in the anoxic chamber 14 and the anaerobic chamber 15 decompose the macromolecular organic matter in the sewage into small molecular organic matter, and convert the insoluble organic matter into soluble organic matter.

[0046] ② The sewage then enters the circulating aeration tank 2. The surface aerator 22 aerates the sewage on the one hand and accelerates the flow of water on the other hand. The drum aerator 23 strengthens the aeration of the sewage. The biochemical filler 24 becomes the carrier of the activated sludge. The sewage circulates along the neutral plate 21 to produce the treatment effect of the oxidation ditch process. The interception grid 26 prevents the biochemical filler from flowing into the downstream.

[0047] ③ The water treated in the circulating aeration tank enters the intermediate sedimentation tank 3 through the overflow plate 25, and the clean water after sedimentation flows into the drainage pipe of the intermediate sedimentation tank through the overflow platform 31. Part of the precipitated sludge flows back to the baffled front tank 1 through the sludge pump and the sludge discharge pipe, and part of it enters the sludge treatment tank for treatment.

[0048] ④ The sewage from the drainage pipe of the intermediate sedimentation tank enters the advanced oxidation chamber 41 through the inlet pipe 413 and the water distribution pipe 412 of the deepening treatment tank. The ozone aeration plate 411 produces a large number of fine bubbles, and the pollutants in the sewage are oxidized into substances that are easy to absorb and adsorb; then the water enters the adsorption chamber 42, and the adsorption filler 421 adsorbs and absorbs the pollutants in the sewage; the adsorbed water enters the separation chamber 44, and the solid matter in the water sinks under the action of gravity, and is discharged to 441 through the sediment discharge pipe at the bottom, and enters the sludge treatment tank for treatment. Then the sewage enters the filter chamber 43, and the filter material 431 filters the water. The filtered water is discharged through the overflow weir 432 of the deepening treatment tank and the outlet pipe of the deepening treatment tank, and is discharged or reused in compliance with the standards.

[0049] It should be noted that the sewage treatment system and method provided in this application is specifically applicable to mixed sewage composed of industrial sewage discharged during the production of dyes, medicines, pesticide intermediates and other chemical products; the water quality indicators of the mixed sewage before treatment are COD500mg / L, BOD5350 mg / L, NH4-N 45mg / L, TN 70mg / L, TP 8mg / L, SS350mg / L. It is understandable that the above water quality indicators fluctuate around this value. The water quality indicators after treatment are COD<50mg / L, BOD5<10mg / L, NH4-N<5 or 8mg / L, TN<15mg / L, TP<0.5mg / L. Among them, the treatment standards that need to be achieved by NH4-N are different according to the season, so there will be two values.

[0050] Those skilled in the art can understand that the above-mentioned embodiments are specific examples for implementing the present application, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of the present application. Any person skilled in the art can make their own changes and modifications without departing from the spirit and scope of the present application, so the scope of protection of the present application shall be based on the scope defined in the claims.

Claims

1. A sewage treatment system, characterized in that: The treatment system comprises a baffled front tank (1), a circulating aeration tank (2), an intermediate sedimentation tank (3) and a deepening treatment tank (4) which are connected in sequence; The baffled pre-tank (1) is used to intercept and decompose the sewage entering the treatment system, so that the sludge in the sewage is intercepted in the reaction tank, and the macromolecular organic matter in the sewage is decomposed into small molecular organic matter, and the insoluble organic matter is converted into soluble organic matter; The circulating aeration tank (2) is used to aerate and push the sewage treated by the baffled front tank (1) and to circulate the sewage to produce the treatment effect of the oxidation ditch process; The intermediate sedimentation tank (3) is used to precipitate the sewage after being treated in the circulating aeration tank (2), and the clear water after precipitation is discharged into the deep treatment tank (4); a part of the precipitated sludge flows back to the baffled front tank (1), and the other part enters the sludge treatment tank for treatment; The further treatment tank (4) is used to sequentially perform oxidation, adsorption and absorption, sedimentation and filtration on the sewage treated by the intermediate sedimentation tank (3), and then discharge it to meet the discharge standards or reuse it.

2. The sewage treatment system according to claim 1, characterized in that: The deep treatment tank (4) comprises an advanced oxidation chamber (41), an adsorption chamber (42), a filtration chamber (43) arranged at the upper part, and a separation chamber (44) arranged at the lower part; The advanced oxidation chamber (41) is used to aerate the sewage so that the pollutants in the sewage are oxidized into substances that are easily absorbed and adsorbed, and the treated sewage is transported to the adsorption chamber (42); The adsorption chamber (42) is used to adsorb and absorb pollutants in the sewage and transport the treated sewage to the separation chamber (44); The separation chamber (44) is used to separate the sewage by gravity, and transport the separated sewage to the filter chamber (43) and discharge the bottom sediment; The filter chamber (43) is used to filter sewage and then discharge it.

3. The sewage treatment system according to claim 2, characterized in that: An ozone aeration plate (411) is provided at the bottom of the advanced oxidation chamber (41), a water distribution pipe (412) is provided below the ozone aeration plate (411), the water distribution pipe (412) is connected to a water inlet pipe (413) of a further treatment tank, and the water inlet pipe (413) of the further treatment tank is connected to a drainage pipe of the intermediate sedimentation tank (3); The ozone aeration plate (411) is connected to an ozone blower, and the ozone blower is connected to an ozone generator; The adsorption chamber (42) is located outside the advanced oxidation chamber (41); an adsorption filler (421) is provided inside the adsorption chamber (42); The filter chamber (43) is located outside the adsorption chamber (42), a filter material (431) is arranged in the filter chamber (43), an overflow weir (432) of the deepening treatment pool is arranged on the upper part of the filter chamber (43), and the overflow weir (432) of the deepening treatment pool is connected to the outlet pipe of the deepening treatment pool; A sediment discharge pipe (441) is provided at the bottom of the separation chamber (44).

4. The sewage treatment system according to claim 3, characterized in that: The adsorption filler (421) is prepared by the following steps: S1. harvesting and drying the reed straw; crushing the reed straw after drying and passing it through a 100-mesh sieve; S2, washing and drying the sieved reed straw, and then putting it into a tubular furnace, introducing nitrogen at a flow rate of 200 mL / min, heating rate of 20 ° C / min, setting the temperature to 800 ° C for 4 h, and then cooling to room temperature to obtain reed straw charcoal; S3, immersing the reed straw charcoal in a hydrogen peroxide solution with a mass concentration of 4%, stirring and soaking at a temperature of 80°C for 2 hours, and then filtering and washing until neutral; S4, immerse the washed reed straw charcoal in 3 mol / L hydrochloric acid at 80°C for 3 hours, then filter and wash until neutral; S5, immerse in a 10% aluminum sulfate solution, stir at 80°C for 30 minutes; filter and dry; S6. Pyrolyze the dried reed straw charcoal under 800° C. for 60 minutes without oxygen; cool to room temperature; and sieve through a 100-mesh sieve to obtain the adsorption filler (421).

5. The sewage treatment system according to claim 1, characterized in that: The baffled front pool (1) comprises an anaerobic chamber (13), an anoxic chamber (14) and an anaerobic chamber (15) which are separated by an outer pool wall (11) and a plurality of baffle walls (12) and are connected in sequence; The head end of the aerobic chamber (13) is provided with a baffled pre-tank water inlet (16) for supplying sewage, and the tail end of the anaerobic chamber (15) is provided with a baffled pre-tank water outlet (17); The upper parts of the anaerobic chamber (13), the anoxic chamber (14) and the anaerobic chamber (15) are all provided with an upper cover and a methane gas collecting and discharging pipe; the baffle wall (12) is vertically arranged with the outer pool wall (11); The baffle wall (12) is used to produce a blocking effect and cooperate with the sedimentation effect of the sludge itself to intercept the sludge in the reaction tank, so that the pollutants in the sewage are fully in contact with the microorganisms; The facultative oxygen chamber (13), the anoxic chamber (14) and the anaerobic chamber (15) are used to decompose macromolecular organic matter in sewage into micromolecular organic matter and convert insoluble organic matter into soluble organic matter by using facultative bacteria and heterotrophic bacteria.

6. The sewage treatment system according to claim 1, characterized in that: The circulating aeration tank comprises a neutral plate (21), a surface aerator (22), a drum aerator (23), a biochemical filler (24), an overflow plate (25) and an interception grid (26); The neutral plate (21) is arranged at the middle position of the circulating aeration tank (2); The surface aerator (22) is arranged at both ends of the neutral plate (21), and the surface aerator (22) is used to push the sewage in the circulating aeration tank (2) to flow around the neutral plate (21); The aerator (23) is arranged on one side of the neutral plate (21), and the aerator (23) is provided with an aeration head and an air distribution pipe, and the air distribution pipe is connected to a blower; The biochemical filler (24) is filled in the circulating aeration tank (2); The overflow plate (25) is located at the end of the circulating aeration tank (2); The interception grid (26) covers the upper part and the front end of the overflow plate (25), and is arranged parallel to the overflow plate (25).

7. The sewage treatment system according to claim 6, characterized in that: The biochemical filler (24) is made of polyethylene and is spherical in shape; The mesh size of the interception grid (26) is smaller than the diameter of the biochemical filler (24).

8. The sewage treatment system according to claim 1, characterized in that: The intermediate sedimentation tank (3) is connected to the overflow plate (25); an overflow platform (31) is provided at the tail of the intermediate sedimentation tank (3), and the outflow water of the overflow platform (31) is collected and discharged by the drainage pipe of the intermediate sedimentation tank; a sludge pump and a sludge discharge pipe are also provided at the bottom of the intermediate sedimentation tank (3).

9. A method for treating sewage, characterized in that: Using the sewage treatment system as described in any one of claims 1 to 8, the treatment method comprises: After the sewage enters the baffled pre-tank from the baffled pre-tank water inlet (16), it moves back and forth along the baffle wall (12), and passes through the facultative anaerobic chamber (13), the anoxic chamber (14) and the anaerobic chamber (15) in sequence. The sludge in the reaction tank moves with the flow of the sewage and the rising action of the methane. The blocking action of the baffle wall (12) and the sedimentation action of the sludge itself reduce the flow rate of the sludge, so that a large amount of sludge is trapped in the reaction tank. The microorganisms in the reaction tank are in full contact with the pollutants in the sewage. The facultative bacteria in the facultative anaerobic chamber (13) and the heterotrophic bacteria in the anoxic chamber (14) and the anaerobic chamber (15) decompose the macromolecular organic matter in the sewage into small molecular organic matter, and convert the insoluble organic matter into soluble organic matter. The sewage then enters the circulating aeration tank (2). The surface aerator (22) aerates the sewage and accelerates the flow of water. The drum aerator (23) intensifies the aeration of the sewage. The biochemical filler (24) becomes a carrier of the activated sludge. The sewage circulates along the neutral plate (21) to produce the treatment effect of the oxidation ditch process. The interception grid (26) prevents the biochemical filler from flowing into the downstream. The sewage then enters the intermediate sedimentation tank (3) through the overflow plate (25), and the clear water after sedimentation flows into the drainage pipe of the intermediate sedimentation tank through the overflow platform (31). Part of the sludge after sedimentation flows back to the baffled front tank (1) through the sludge pump and the sludge discharge pipe, and part of it enters the sludge treatment tank for treatment; The sewage from the drainage pipe of the intermediate sedimentation tank enters the advanced oxidation chamber (41) through the inlet pipe (413) and the water distribution pipe (412) of the deepening treatment tank, and the ozone aeration plate (411) generates a large number of fine bubbles, and the pollutants in the sewage are oxidized into substances that are easy to absorb and adsorb; then the water enters the adsorption chamber (42), and the adsorption filler (421) adsorbs and absorbs the pollutants in the sewage; the adsorbed water enters the separation chamber (44), and the solid matter in the water sinks under the action of gravity, and is discharged to (441) through the sediment discharge pipe at the bottom, and enters the sludge treatment tank for treatment; then the sewage enters the filter chamber (43), and the filter material (431) filters the water, and the filtered water is discharged through the overflow weir (432) of the deepening treatment tank and the outlet pipe of the deepening treatment tank, and is discharged or reused in compliance with the standards.

10. Application of the sewage treatment system according to any one of claims 1 to 8 in the field of urban sewage treatment, characterized in that: The sewage is specifically mixed sewage composed of industrial sewage discharged during the production of dyes, medicines, pesticide intermediates and other chemical products; wherein the water quality indicators of the mixed sewage before treatment are COD 500mg / L, BOD5350mg / L, NH4-N 45mg / L, TN 70mg / L, TP 8mg / L, SS 350mg / L; the water quality indicators after treatment are COD<50mg / L, BOD5<10mg / L, NH4-N<5(8)mg / L, TN<15mg / L, TP<0.5mg / L.

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