Container formula electro-Fenton biochemical pond MBR membrane allies oneself with uses water treatment system
Technical Field
The invention belongs to the technical field of water treatment, and particularly relates to a container type electro-Fenton biochemical pool MBR membrane combined water treatment system.
Background
Along with the acceleration of the national urbanization process, the quality of urban domestic sewage and industrial wastewater is increasingly deteriorated, and especially, main pollution indexes such as organic matters, ammonia nitrogen and the like are continuously increased, so that huge pressure is brought to the treatment of the wastewater. Organic matters in the water body are mainly caused by discharge of urban domestic sewage, industrial wastewater of food, paper making and the like, organic pollutants are often subjected to anaerobic reaction to generate various reducing gases, and the gases cause that animals and plants in the water are difficult to survive, generate stink and seriously pollute the ecological environment of the water body. The main sources of ammonia nitrogen in the water body comprise domestic sewage, petrochemical industry, chemical fertilizer industry and the like, the pH value of the water body can be changed to destroy the ecological balance when the content is too high, the toxicity of the ammonia nitrogen is far higher than that of ammonium salt, and the probability of human and other organisms suffering from diseases is greatly improved.
The existing mature water treatment methods mainly comprise three major methods, namely a physical adsorption method, a chemical oxidation method and a biological method, and the most common method is an activated sludge method in the biological method. The main methods for removing ammonia nitrogen are physical stripping, chemical oxidation, biological methods and the like. Under the actual production condition, the content of organic matters and ammonia nitrogen in the water body is often required to be reduced at the same time, so a biological method is often adopted for water treatment, such as A2The O process mainly comprises an anaerobic section, an anoxic section, an aerobic section and a sedimentation tank, and although the process is widely applied, the process still has obvious defects, such as the problems of contradiction between sludge ages of various strains, interference of dissolved oxygen in circulating water, sludge expansion, floating and the like, directly results in long wastewater treatment period and unsatisfactory effect, and the large construction amount and the wide occupied area in the construction process further limit the application universality.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provides a container type electro-Fenton biochemical pool MBR membrane combined water treatment system.
This kind of container formula electro-fenton biochemical pond MBR membrane allies oneself with uses water treatment system includes: the device comprises a reaction tank body, a dosing device, a backwashing device, a sludge pump, a PLC control cabinet and a container body; the reaction tank body, the dosing device, the backwashing device, the sludge pump and the PLC control cabinet are all arranged in the container body so as to be convenient for integral movement and arrangement;
the side vertical surface of the container body is provided with an exhaust fan, the top of the container body is provided with a plurality of maintenance holes for personnel to check and maintain, and the top and the side of the container body are respectively provided with a longitudinal reinforcing rib and a transverse reinforcing square tube so as to enhance the strength of the container body; an XPS extruded sheet heat-insulating layer is additionally arranged on the inner side of the container body;
the PLC control cabinet is connected with a power supply and is electrically connected with the reflux pump, the suction pump, the backwashing water pump, the dosing pump, the aeration fan, the stirrer, the sludge pump and the exhaust fan and used for starting and stopping the whole equipment and regulating and controlling parameters; the dosing device comprises a NaOH dosing barrel, an HCl dosing barrel and a dosing pump; the backwashing device comprises a chemical backwashing chemical feeding barrel and a backwashing water pump; the chemical backwashing chemical dosing barrel is connected with an outlet pipe of the backwashing water pump through a dosing pump, and a branch is provided with an electromagnetic valve;
the reaction tank body comprises a primary regulating tank, an electro-Fenton oxidation tank, a secondary regulating tank, an anoxic tank, an aerobic tank, an MBR membrane tank and a clean water tank; the primary regulating tank, the electro-Fenton oxidation tank, the secondary regulating tank, the anoxic tank, the aerobic tank and the MBR membrane tank are connected in series to be integrated for wastewater treatment; the bottoms of the secondary regulating tank, the anoxic tank, the aerobic tank and the MBR membrane tank are provided with sludge discharge pipelines connected with a sludge discharge pump; manual valves are arranged on the sludge discharge pipelines, and sludge is uniformly discharged to a sludge recovery barrel outside the container body through a sludge discharge pump; a variable-frequency aeration fan is arranged at one side of an inlet of the incoming water in the reaction tank body; the outer side of the primary regulating tank is provided with an incoming water inlet, the top of the inner side of the primary regulating tank is provided with a stirrer and a dosing pipe, and the tail end of the dosing pipe is connected with a dosing pump and an HCl dosing barrel;
the top of the electro-Fenton oxidation tank is provided with an electrolysis power supply; the underwater part of the electro-Fenton oxidation pond is provided with a Fenton water distributor and an oxidation pond aeration pipe connected with the outlet of the aeration fan;
the top of the inner side of the secondary regulating tank is provided with a stirrer and a dosing pipe, and the tail end of the dosing pipe is connected with a dosing pump and a NaOH dosing barrel;
elastic filler is arranged in the anoxic tank to provide attachment points for microorganisms, and the elastic filler is supported and suspended in the anoxic tank by a stainless steel filler frame;
the aerobic tank is internally provided with combined fillers, and the bottom of the aerobic tank is provided with an aerobic tank aeration pipe connected with the outlet of the aeration fan;
a PVDF hollow fiber curtain type membrane group is arranged in the MBR membrane tank, and membrane backwashing equipment is arranged outside the MBR membrane tank; the hollow fiber curtain type membrane group comprises a membrane frame and an MBR membrane arranged on the membrane frame; a suction upright post and a perforated water collecting beam are arranged on the membrane frame, a suction interface is arranged at the top end of the suction upright post, the suction interface is connected with a suction pump inlet pipe and a backwash water pump outlet pipe, an aeration pipeline connected with an outlet of an aeration fan is arranged at the bottom of the MBR membrane tank, and an aeration pipeline at the bottom of the MBR membrane tank is aerated by adopting a membrane tank aeration disc;
the upper part of the inner side of the clean water tank is provided with a water inlet pipe and a water pumping pipe, and the bottom of the clean water tank is provided with a water producing port; the water inlet end of the backwashing water pump is connected with the clean water tank through a water pumping pipe, and the water outlet end of the backwashing water pump is connected with a suction interface of the MBR membrane tank membrane frame through an outlet pipe; the clean water tank is connected with the water outlet end of the suction pump through a water inlet pipe.
As preferred, the bottom plate, the wallboard and the inner baffle of reaction cell body all adopt 6 ~ 8 mm's carbon steel board (stainless steel material), and the reaction cell body inner wall is handled by epoxy anticorrosion, and the reaction cell body outer wall is handled by perchloroethylene anticorrosive paint, ensures firm corrosion-resistant and each processing unit is separated by the stainless steel baffle.
Preferably, the anode of an electrolytic power supply at the top of the electro-Fenton oxidation tank is connected with a carbon steel anode electrode (iron electrode), and the cathode of the electrolytic power supply is connected with a graphite cathode electrode (graphite electrode); the electrode is replaced in time according to the electrode consumption condition in the using process.
Preferably, the aeration pipe of the oxidation pond adopts pipe type aeration, and the aeration pipe of the aerobic pond also adopts pipe type aeration.
Preferably, the suction upright column and the perforated water collecting beam arranged on the membrane frame of the MBR membrane tank are both made of square stainless steel tubes.
Preferably, the water producing port at the bottom of the clean water pond is used for discharging water produced by the clean water pond.
The working method of the container type electro-Fenton biochemical pool MBR membrane combined water treatment system specifically comprises the following steps:
step 1, incoming water firstly enters a primary regulating reservoir through an incoming water inlet, since the oxidative decomposition of organic matters by a Fenton reagent needs to be carried out under a weak acidic condition, dilute hydrochloric acid needs to be added into the primary regulating reservoir through an HCl dosing barrel and a dosing pump to maintain the pH value of the incoming water at a set value, and the incoming water is uniformly stirred by a stirrer to regulate the water quality in the primary regulating reservoir to be weak acidic; when the first-stage regulating reservoir needs chemical backwashing, introducing NaClO solution or HCl solution through an HCl dosing barrel by a dosing pump;
step 2, water in the primary regulating tank automatically flows into the electro-Fenton oxidation tank from the bottom of the primary regulating tank, and the variable-frequency aeration fan aerates the electro-Fenton oxidation tank through an aeration pipe of the oxidation tank; the Fenton (Fenton) reagent method is an effective method for oxidizing and treating refractory organic pollutants, and the Fenton reagent (Fe)2+/H2O2) The reaction principle of the system is H2O2In Fe2+Generates hydroxyl free radicals with extremely high oxidation potential to oxidize and degrade organic pollutants in water under the catalytic action, has more thorough COD removal effect and higher pollutant concentration load compared with the traditional biochemical method, and utilizes Fe generated by the electrochemical method in the electro-Fenton method2+And H2O2Therefore, no additional Fenton reagent is needed in the treatment process; o at the cathode of the electrolytic power supply at the top of the electro-Fenton oxidation cell2The molecule gains electrons and is reduced to H2O2And Fe obtained by oxidation at the same time3+Reduction of the electrons to Fe is likewise obtained2+Adjusting the intensity of applied voltage to make Fe2+And H2O2The quantity concentration ratio of the substances is controlled at a set value, Fe2+Continuing the catalytic reaction; oxidizing and decomposing organic components in the water into micromolecular organic matters or inorganic components by a Fenton reagent so as to provide conditions for subsequent biochemical treatment;
step 3,The water after the electro-Fenton oxidation pond is handled flows automatically from the overflow weir of electro-Fenton oxidation pond upper portion and gets into the second grade equalizing basin, and the NaOH adds the explosive barrel and adds the NaOH solution in to the second grade equalizing basin through adding the pencil and adding the medicine pump, adjusts the pH in the second grade equalizing basin to neutrality (between 6 ~ 9), and Fe2+And Fe3+Respectively with Fe (OH)2And Fe (OH)3Precipitation in the form of (1);
step 4, the biochemical treatment system is mainly an AO process, namely, the biochemical treatment system is formed by connecting an anoxic tank and an aerobic tank in series, and ammonia nitrogen is effectively converted into nitrogen by utilizing the nitrification and denitrification of bacteria; sewage in the secondary regulating tank automatically flows into an anoxic tank from an overflow weir at the upper part of the secondary regulating tank, the anoxic tank is favorable for growth of anoxic microorganisms, a proper amount of nutrient substances and trace elements are added at an anoxic section to maintain nutrients required by normal metabolism of the microorganisms, denitrifying bacteria in the anoxic tank utilize organic matters as electron donors under anaerobic conditions to reduce nitrate nitrogen and nitrite nitrogen into nitrogen, and the obtained nitrogen is discharged into the air;
wastewater in the anoxic tank automatically flows into the aerobic tank from an overflow weir at the upper part of the anoxic tank, and the variable-frequency aeration fan aerates the aerobic tank through an aeration pipe of the aerobic tank; in the aerobic tank, nitrifying bacteria convert ammonia nitrogen into nitrate nitrogen and nitrite nitrogen, and part of wastewater treated by the nitrifying bacteria flows back to the anoxic tank through a reflux pump according to a reflux ratio to perform denitrification;
step 5, enabling the water subjected to biochemical treatment in the aerobic tank to automatically flow into an MBR membrane tank, retaining suspended particulate matters and bacteria existing in the wastewater on the surface of an MBR membrane in the MBR membrane tank, and enabling the produced water (final produced water) in the MBR membrane tank to enter a clean water tank through a suction pump; in the working process of the MBR membrane tank, the variable-frequency aeration fan vibrates and cleans the MBR membrane in an intermittent aeration mode through a membrane tank aeration disc at the bottom of the MBR membrane tank;
step 6, lifting one part of produced water in the clean water tank to an MBR membrane tank by a backwash water pump for chemical backwash of an MBR membrane, and discharging the other part of the produced water through a water producing port for continuous utilization;
and 7, periodically discharging the sludge generated by the secondary regulating tank, the anoxic tank, the aerobic tank and the MBR membrane tank out by a sludge discharge pump through branch pipes.
Preferably, the stepsThe pH value of the inlet water in the primary regulating tank in the step 1 is about 4; in the step 2, the pH value in the electro-Fenton oxidation tank is controlled to be 3-4, the temperature is controlled to be 15-40 ℃, and the contact time of the incoming water and the Fenton reagent in the primary regulating tank is not less than 30 min; fe2+And H2O2The quantitative concentration ratio of the substances is set to (1:5) - (1:25), H2O2The mass concentration ratio of the water to COD is 1:1, and the specific concentration is adjusted according to the COD of the incoming water.
Preferably, in the step 4, the concentration of dissolved oxygen in the aerobic pool is controlled to be 2-4 mg/L; the reflux ratio of partial wastewater treated by nitrobacteria is about 200 to 300 percent; considering the biochemical activity of the strain, the sewage temperature of the secondary regulating tank is 15-35 ℃.
Preferably, in step 5, the MBR membrane is a UF hollow fiber curtain membrane made of PVDF material, and the membrane pore diameter is 0.01-0.1 μm.
The invention has the beneficial effects that:
the integrated container equipment adopted by the invention is mainly used for treating the organic ammonia nitrogen wastewater with different water qualities, and experiments prove that the integrated container equipment is especially COD (chemical oxygen demand)crLess than or equal to 5000mg/L and NH4 +The removal efficiency of agricultural production wastewater and urban domestic sewage with-N less than or equal to 100mg/L can respectively reach more than 90% under the stable operation condition.
The method utilizes the Fenton technology to carry out oxidative decomposition on the organic matters without manually adding a Fenton reagent, particularly, the organic matters which are difficult to degrade can be directly degraded into an inorganic state, and the method is combined with a biological treatment method, so that the removal efficiency and the removal load of the system on the organic matters are greatly improved. Utilize the advantage of membrane separation technique and biological treatment technique, not only can get rid of the suspended solid completely in order to improve out water quality of water, can keep apart the free bacterium that can't be held back in the secondary sedimentation pond among the traditional approach and macromolecule organic matter in the biological pond completely through membrane separation's effect moreover, also can effectively filter the suspended solid when guaranteeing the water yield.
The whole set of processing equipment and the control equipment of the device are reasonably installed in the reinforced container, so that the device is convenient for batch production and has the advantages of short construction period, simple and compact structure and convenient movement.
Drawings
FIG. 1 is a schematic view of the internal structure of MBR membrane combined water treatment equipment for a container type electro-Fenton biochemical tank;
FIG. 2 is a top view of the internal structure of the MBR membrane combined water treatment device in the container type electro-Fenton biochemical tank;
FIG. 3 is a top view of the external structure of the MBR membrane combined water treatment device in the container type electro-Fenton biochemical tank;
FIG. 4 is a flow chart of the water treatment apparatus.
Description of reference numerals: the device comprises a reaction tank body 1, a primary regulating tank 2, an electro-Fenton oxidation tank 3, a secondary regulating tank 4, an anoxic tank 5, an aerobic tank 6, an MBR membrane tank 7, a clean water tank 8, an incoming water inlet 9, an electrolysis power supply 10, an oxidation tank aeration pipe 11, an elastic filler 12, a combined filler 13, an aerobic tank aeration pipe 14, a reflux pump 15, a hollow fiber curtain type membrane group 16, a membrane tank aeration disc 17, a suction pump 18, a water production port 19, a backwash water pump 20, a dosing pump 21, a chemical backwash dosing barrel 22, an NaOH dosing barrel 23, an HCl dosing barrel 24, an aeration fan 25, a stirrer 26, a sludge discharge pump 27, a PLC control cabinet 28, an exhaust fan 29, a container body 30, a maintenance hole 31, a reinforcing rib 32 and a reinforcing square pipe 33.
Detailed Description
The present invention will be further described with reference to the following examples. The following examples are set forth merely to aid in the understanding of the invention. It should be noted that, for a person skilled in the art, several modifications can be made to the invention without departing from the principle of the invention, and these modifications and modifications also fall within the protection scope of the claims of the present invention.
Example 1:
as shown in fig. 1 to 3, a container type electro-fenton biochemical pond MBR membrane combined water treatment system comprises: the device comprises a reaction tank body 1, a dosing device, a backwashing device, a sludge pump 27, a PLC control cabinet 28 and a container body 30; the reaction tank body 1, the dosing device, the backwashing device, the sludge pump 27 and the PLC control cabinet 28 are all arranged in a container body 30 so as to be integrally moved and placed;
an exhaust fan 29 is arranged on the vertical surface of the side of the container body 30, a plurality of maintenance holes 31 for personnel to check and maintain are arranged on the top of the container body 30, and a longitudinal reinforcing rib 32 and a transverse reinforcing square tube 33 are additionally arranged on the top and the side of the container body 30 so as to enhance the strength of the container body; an XPS extruded sheet heat-insulating layer is additionally arranged on the inner side of the container body 30;
the PLC control cabinet 28 is connected with a power supply, and the PLC control cabinet 28 is electrically connected with the reflux pump 15, the suction pump 18, the backwashing water pump 20, the dosing pump 21, the aeration fan 25, the stirrer 26, the sludge pump 27 and the exhaust fan 29 and is used for starting and stopping the whole equipment and regulating and controlling parameters; the dosing devices are a NaOH dosing barrel 23, an HCl dosing barrel 24 and a dosing pump 21; the backwashing device comprises a chemical backwashing dosing barrel 22 and a backwashing water pump 20; the chemical backwashing dosing barrel 22 is connected with an outlet pipe of a backwashing water pump 20 through a dosing pump 21, and a branch is provided with an electromagnetic valve;
the reaction tank body 1 comprises a primary regulating tank 2, an electro-Fenton oxidation tank 3, a secondary regulating tank 4, an anoxic tank 5, an aerobic tank 6, an MBR membrane tank 7 and a clean water tank 8; the primary regulating tank 2, the electro-Fenton oxidation tank 3, the secondary regulating tank 4, the anoxic tank 5, the aerobic tank 6 and the MBR membrane tank 7 are connected in series to be integrated for wastewater treatment; the bottoms of the secondary regulating tank 4, the anoxic tank 5, the aerobic tank 6 and the MBR membrane tank 7 are provided with sludge discharge pipelines connected with a sludge discharge pump 27; each sludge discharge pipeline is provided with a manual valve, and sludge is uniformly discharged to a sludge recovery barrel outside the container body by a sludge discharge pump 27; a variable-frequency aeration fan 25 is arranged at one side of an incoming water inlet 9 in the reaction tank body 1; an incoming water inlet 9 is arranged on the outer side of the primary regulating tank 2, a stirrer 26 and a dosing pipe are arranged at the top of the inner side of the primary regulating tank 2, and the tail end of the dosing pipe is connected with a dosing pump 21 and an HCl dosing barrel 24;
the top of the electro-Fenton oxidation tank 3 is provided with an electrolysis power supply 10; the underwater part of the electro-Fenton oxidation pond 3 is provided with a Fenton water distributor and an oxidation pond aeration pipe 11 connected with the outlet of an aeration fan 25;
the top of the inner side of the secondary regulating tank 4 is provided with a stirrer 26 and a dosing pipe, and the tail end of the dosing pipe is connected with a dosing pump 21 and a NaOH dosing barrel 23;
an elastic filler 12 is arranged in the anoxic tank 5 to provide attachment points for microorganisms, and the elastic filler 12 is supported and suspended in the anoxic tank 5 by a stainless steel filler frame;
the aerobic tank 6 is internally provided with combined fillers 13, and the bottom of the aerobic tank 6 is provided with an aerobic tank aeration pipe 14 connected with the outlet of an aeration fan 25;
a PVDF hollow fiber curtain type membrane group 16 is arranged in the MBR membrane tank 7, and membrane backwashing equipment is arranged outside the MBR membrane tank 7; the hollow fiber curtain type membrane module 16 comprises a membrane frame and an MBR membrane arranged on the membrane frame; a suction upright post and a perforated water collecting beam are arranged on the membrane frame, the top end of the suction upright post is provided with a suction interface, the suction interface is connected with an inlet pipe of a suction pump 18 and an outlet pipe of a backwashing water pump 20, the bottom of the MBR membrane tank 7 is provided with an aeration pipeline connected with an outlet of an aeration fan 25, and the aeration pipeline at the bottom of the MBR membrane tank 7 is aerated by adopting a membrane tank aeration disc 17;
the upper part of the inner side of the clean water tank 8 is provided with a water inlet pipe and a water pumping pipe, and the bottom of the clean water tank 8 is provided with a water producing port 19; the water inlet end of the backwashing water pump 20 is connected with the clean water tank 8 through a water pumping pipe, and the water outlet end of the backwashing water pump 20 is connected with a suction interface of the membrane frame of the MBR membrane tank 7 through an outlet pipe; the clean water tank 8 is connected with the water outlet end of the suction pump 18 through a water inlet pipe.
Example 2:
in addition to example 1, as shown in fig. 4, the MBR membrane-coupled water treatment device in the container-type electro-Fenton biochemical tank adopted in this example has a daily average sewage treatment capacity of 35m3The inner tank body is made of 316L type stainless steel and an anticorrosive coating, the total effective size L multiplied by B multiplied by H of the tank body is 9.1 multiplied by 2m multiplied by 1.7m, wherein the effective length of an adjusting tank 1 is 0.6m, the effective length of an electro-Fenton tank is 2.6m, the effective length of an adjusting tank 2 is 0.6m, the effective length of an anoxic tank is 1.4m, the effective length of an aerobic tank is 1.7m, the effective length of an MBR membrane tank is 1.4m, the effective length of a clean water tank is 0.8m, the material of an external customized container is carbon steel, and the size L multiplied by B multiplied by H is 12 multiplied by 3.2m multiplied by 3 m. The total hydraulic retention time of the device is about 21.2h, wherein the respective hydraulic retention times of the electro-Fenton pool, the anoxic pool and the aerobic pool are 6h, 3.3h and 4.0 h. The sludge age is 45d, the sludge concentration is maintained at about 3800mg/L, the Dissolved Oxygen (DO) in an aerobic zone is 3.4mg/L, the Dissolved Oxygen (DO) in an anoxic zone is 0.6mg/L, and a UF hollow fiber curtain type membrane made of PVDF material is adopted in a membrane pool, and the aperture is 0.01 mu m.
Table 1 example 2 mean water inflow and production parameters for one and two weeks after smooth operation
As shown in Table 1, the apparatus described in example 2 was put into operation after the procedures of preliminary installation and debugging and acclimation of activated sludge, and H in the electro-Fenton cell was determined based on the results of the pilot plant2O2The concentration is maintained at about 25mmol/L, Fe2+The ion concentration is maintained at about 3 mmol/L. And (4) continuously detecting the quality of the inlet and outlet water for two weeks after the operation is stable, wherein the raw water is the wastewater of a certain nearby slaughterhouse. As shown in Table 1, COD in the first weekCrThe average removal rate was 92%; NH (NH)4 +-an average value of N removal of 94%; the average TN removal was 71%. COD in the second weekCrThe average removal rate was 93%; NH (NH)4 +-an average value of N removal of 96%; the average value of TN removal rate is 72%, so that the running condition of the equipment is good, and the effluent quality is stable and is slightly improved. A
Example 3:
based on example 1, the MBR membrane combined water treatment device of the container type electro-Fenton biochemical tank adopted in the present example has a daily average sewage treatment capacity of 26m3The inner tank body is made of 316L type stainless steel and an anticorrosive coating, the total effective size L multiplied by B multiplied by H of the tank body is 6.5m multiplied by 1.6m multiplied by 1.5m, wherein the effective length of an adjusting tank 1 is 0.4m, the effective length of an electro-Fenton tank is 1.8m, the effective length of an adjusting tank 2 is 0.4m, the effective length of an anoxic tank is 1m, the effective length of an aerobic tank is 1.3m, the effective length of an MBR membrane tank is 1m, the effective length of a clean water tank is 0.6m, the material of an external customized container is carbon steel, and the size L multiplied by B multiplied by H is 8.4m multiplied by 2.4 m. The total hydraulic retention time of the device is about 14.5h, wherein the respective hydraulic retention times of the electro-Fenton pool, the anoxic pool and the aerobic pool are 4h, 2.2h and 2.9 h. The sludge age was 50 days, the sludge concentration was maintained at about 4200mg/L, the Dissolved Oxygen (DO) in the aerobic zone was 3.7mg/L, the Dissolved Oxygen (DO) in the anoxic zone was 0.5mg/L, and the membrane tank was made of a PVDF UF hollow fiber curtain membrane with a pore diameter of 0.01. mu.m.
Table 2 example 3 average water intake and production parameters for one and two weeks after smooth operation
The device described in example 3 was put into operation after the procedures of preliminary installation and debugging and acclimation of activated sludge, and the H in the electro-Fenton cell was determined according to the bench test results2O2The concentration is maintained at about 14mmol/L, Fe2+The ion concentration is maintained at about 2 mmol/L. And (4) detecting the quality of inlet and outlet water continuously for two weeks after the operation is stable, wherein the raw water is biological sewage of a certain nearby residential area. As shown in Table 2 above, the first cycle CODCrThe average removal rate was 94%; NH (NH)4 +The average N removal was 97%; the average TN removal was 72%. COD in the second weekCrThe average removal rate is 95%; NH (NH)4 +The average N removal was 97%; the average value of TN removal rate is 71%, so that the operation condition of the equipment is good, the effluent quality is stable, and the effluent quality reaches the first-class A standard.