CN112479368A

CN112479368A - Sewage treatment device of biofilm reactor and treatment method thereof

Info

Publication number: CN112479368A
Application number: CN202011238972.6A
Authority: CN
Inventors: 辛刚
Original assignee: Shandong Youwei Environmental Protection Service Co ltd
Current assignee: Shandong Youwei Environmental Protection Service Co ltd
Priority date: 2020-11-09
Filing date: 2020-11-09
Publication date: 2021-03-12

Abstract

The invention discloses a sewage treatment device of a biofilm reactor and a treatment method thereof, the sewage treatment device of the biofilm reactor comprises an improved biofilm reactor, the improved biofilm reactor is respectively provided with an aeration system, a stirring device, a suspended filler and a screen, the water outlet end of the improved biofilm reactor is communicated with a membrane pool, the membrane pool is internally provided with a membrane component, a mud-water separation unit is arranged between the membrane pool and the improved biofilm reactor and is communicated with the membrane pool through a reflux pump, the reflux pump is used for conveying sludge and sewage in the membrane pool to the mud-water separation unit, supernatant obtained after the mud-water separation unit separates the sludge flows back to the improved biofilm reactor through gravity, the improved biofilm reaction treatment process and the membrane treatment process are combined, the sewage treatment effect is improved, the effluent quality is good, the subsequent structures such as a secondary sedimentation tank are saved, the occupied area is reduced.

Description

Sewage treatment device of biofilm reactor and treatment method thereof

Technical Field

The invention relates to a sewage treatment device, in particular to a sewage treatment device of a biofilm reactor and a treatment method thereof, and belongs to the technical field of sewage treatment.

Background

In recent years, with the development of modern industry and the requirements of production and living of people, the discharge amount of industrial wastewater and domestic sewage is increased day by day, a large amount of domestic and industrial sewage flows into rivers, lakes or underground water, the water environment pollution is serious day by day, the water resource shortage caused by the pollution is one of important restriction factors of sustainable development and progress of the economy and the society in China, in order to improve the conditions of water pollution and water resource deficiency, a large amount of manpower and material resources are input in China, a large amount of sewage treatment plants are built to treat the sewage, and primary effects are obtained.

As a traditional sewage treatment process, an activated sludge method is widely applied to various large sewage treatment plants, but the traditional activated sludge method has the problems of large floor area, long construction period, unsatisfactory treatment effect, impact load intolerance of a sewage treatment system, unstable effluent quality, large production amount of excess sludge, high sludge treatment cost and the like.

At present, the traditional Activated Sludge Process and its modification Process mainly comprise ApO (Anaerobic/aerobic), ANO (Anaerobic/aerobic), A2/O (Anaerobic/aerobic), CASS (Cyclic Activated Sludge System), SBR (Sequencing Batch Reactor Activated Sludge Process), oxidation ditch and the like, and the purpose is mainly to remove suspended matters, organic pollutants and a part of nitrogen and phosphorus in sewage, reach the standard and discharge, thereby reducing the harm to the environment.

With the development of economy and the improvement of the living standard of people in recent years, the national requirements on environmental protection are increasingly improved, the sewage discharge standard is further improved, and the traditional sewage treatment process has poor treatment effect on nitrogen and phosphorus and cannot meet the sewage discharge requirement.

To solve the above problems occurring in the sewage treatment process, more and more new sewage treatment processes are applied to sewage treatment, such as MBR, MBBR, and the like. In addition, an MBBR and MBR integrated process appears in the prior art, and the process has the following patent numbers: 201710628555.4 discloses an MBBR and MBR integrated process and equipment for water treatment plant, wherein an aeration system is arranged in the water treatment plant, MBBR suspended filler and MBR membrane modules are arranged, a gap allowing the MBBR suspended filler to pass through is kept between each MBR membrane, the MBBR filler rubs the MBR membranes in the flowing process, attachments on the surfaces of the MBR membranes are rubbed and cleaned by the MBBR filler, and a sludge discharge system is arranged at the bottom of the tank.

The MBBR and MBR integrated process and equipment can be used for treating sewage, and the MBBR filler and the MBR membrane are rubbed to ensure that attachments on the surface of the MBR membrane are rubbed and cleaned by the MBBR filler, the MBR membrane is placed to be blocked by the attachments, but the sewage treatment equipment is easy to generate membrane pollution in the operation process, suspended pollutants, soluble organic matters and microorganisms in the sewage are deposited on the surface of the membrane to greatly reduce the membrane flux, secondly, the investment cost is high, the manufacturing cost of the MBR membrane is high, the investment cost of the MBR process is high, the operation cost is high, when the membrane is polluted, the MBR membrane needs to be cleaned, chemical agents used in membrane cleaning also increase the sewage treatment cost, the MBBR filler is distributed around the MBR membrane, the MBR filler and the MBR friction membrane can be used for cleaning the attachments on the MBR membrane, and the MBBR filler rubs the membrane for a long time, can shorten the life of MBR membrane with MBR membrane scratch to owing to add in the washing water that washs the MBR membrane has chemical agent, chemical agent's use causes the damage to the MBR membrane easily, shortens the life of MBR membrane greatly, increases the change frequency of MBR membrane, thereby further increases sewage treatment working costs.

And the MBBR technology in the sewage treatment equipment also has the problems of low oxygen transfer rate, high energy consumption, poor TP removal effect and the like.

Disclosure of Invention

The invention aims to solve the main technical problem of providing a sewage treatment device of a biofilm reactor, which has the advantages of small occupied area, high volume load, good treatment effect, impact load resistance, good effluent quality, low investment cost, low operation cost and convenient operation and maintenance.

In order to solve the technical problems, the invention provides the following technical scheme:

a sewage treatment device of a biofilm reactor comprises an improved biofilm reactor, wherein an aeration system, a stirring device, a suspended filler and a screen are respectively arranged on the improved biofilm reactor, a water outlet end of the improved biofilm reactor is communicated with a membrane pool, a membrane component is arranged in the membrane pool, a mud-water separation unit is arranged between the membrane pool and the improved biofilm reactor, the mud-water separation unit is communicated with the membrane pool through a reflux pump, the reflux pump is used for conveying sludge and sewage in the membrane pool to the mud-water separation unit, and supernatant obtained after the sludge is separated by the mud-water separation unit flows back to the improved biofilm reactor through gravity.

The following is a further optimization of the above technical solution of the present invention:

the improved biomembrane reactor comprises a tank body, wherein at least one stage of denitrification tank and at least one stage of aerobic tank are sequentially arranged in the tank body according to the treatment trend of sewage, the water outlet end of the aerobic tank is communicated with a post-positioned denitrification tank, and the last stage of aerobic tank is communicated with the denitrification tank through a sewage circulating pipeline.

Further optimization: the denitrification tank, the aerobic tank and the post-positioned denitrification tank are respectively filled with suspended fillers, the filling amount of the suspended fillers in each tank is 60-80%, the specific gravity is 0.96-0.98, and the specific surface area is 300-800 m²/m³。

Further optimization: the sewage circulating pipeline comprises an internal circulating pump, a water inlet of the internal circulating pump is communicated with the aerobic tank through a water inlet pipe, and a water outlet of the internal circulating pump is communicated with the denitrification tank through a water outlet pipe.

Further optimization: the water outlet of the improved biomembrane reactor is communicated with a membrane tank through a water outlet pipeline, a chemical reaction tank is connected in series on the water outlet pipeline, and a phosphorus removing agent feeding device is arranged on the chemical reaction tank.

Further optimization: the aeration component is arranged outside the membrane pool, high-pressure gas is conveyed into the membrane pool by the aeration component and is used for colliding the membrane component to clean the membrane component, and the flushing component used for flushing the membrane component is arranged on the membrane pool.

Further optimization: the liquid level in the mud-water separation unit is higher than that of the aerobic tank, and the water outlet end of the mud-water separation unit is communicated with the aerobic tank through a supernatant liquid water conveying pipeline.

Further optimization: the liquid level in the mud-water separation unit is lower than that of the denitrification tank, the liquid outlet of the denitrification tank is communicated with the denitrification tank through a washing water return pipeline, and the washing water in the denitrification tank flows back to the mud-water separation unit through gravity flow and a washing water return pipeline.

The invention also provides a sewage treatment method of the biofilm reactor, based on the sewage treatment device of the biofilm reactor, the treatment method comprises the following steps:

s1, the sewage to be treated enters a denitrification tank through a main water inlet pipeline, the sewage in the denitrification tank is mixed with the nitrifying liquid flowing back from the aerobic tank, part of total nitrogen in the sewage is removed through denitrification, and part of BOD is removed simultaneously₅And CODcr;

s2, the effluent of the denitrification tank automatically flows into an aerobic tank by gravity, and organic pollutants in the sewage are degraded under the action of aerobic microorganisms to remove BOD (biochemical oxygen demand) contained in the sewage₅CODcr and ammonia nitrogen, wherein part of the effluent treated by the aerobic tank enters the subsequent process, and the other part of the effluent returns to the denitrification tank through an internal circulating pump;

s3, under the conditions that the carbon-nitrogen ratio of inlet water is lower than 3.5 and the requirement on the total nitrogen concentration of outlet water is high, the outlet water of the aerobic tank enters a post-denitrification tank, ammonia nitrogen contained in sewage is converted into nitrogen to be removed under the action of denitrifying bacteria, and a carbon source feeding device works to provide a carbon source required by post-denitrification and ensure that the denitrification is normally carried out;

s4, feeding the sewage treated by the improved bio-membrane reactor into a water outlet pipeline, feeding a phosphorus removing agent into a phosphorus removing agent feeding device for removing phosphate in the sewage, and then feeding the sewage into a membrane pool, wherein the membrane module is used for further biochemical treatment and physical filtration of the sewage after biochemical treatment;

s5, conveying the sludge part in the membrane tank to a mud-water separation unit through a return pump, performing solid-liquid separation to obtain sludge and supernatant, discharging the sludge through a sludge discharge pipe, and returning the supernatant to the aerobic tank through a supernatant water conveying pipeline for biochemical treatment.

and S4, conveying the sludge separated by the membrane module to a mud-water separation unit through a reflux pump, and aerating the membrane module by an aeration module of the membrane module for washing the surface of the membrane module.

This adopts above-mentioned technical scheme, has following beneficial effect:

(1) compared with the traditional sewage treatment device and process, the improved biological membrane reaction treatment process and the membrane treatment process can be combined, the sewage treatment effect is improved, the biomass concentration in the improved biological membrane reactor is high, the activity is high, the volume load is high, the occupied area is greatly reduced, at least 100% of the occupied area can be reduced compared with the active sludge process, suspended matters in water are intercepted by the membrane component, the effluent quality is good, the subsequent structures such as a secondary sedimentation tank and the like are saved, the occupied area is further reduced, and the civil engineering cost is saved.

(2) The membrane tank is a split type, sewage to be treated firstly enters the improved biofilm reactor, organic pollutants, ammonia nitrogen and total nitrogen in the sewage are decomposed and metabolized in the improved biofilm reactor, and then the concentration of the organic pollutants entering the membrane tank is low, so that the pollution to the membrane component is reduced, and the service life of the membrane component is prolonged.

(3) The improved biomembrane reactor has high concentration of biomass, mainly takes the biomembrane loaded on the suspended filler as the main material, has low concentration of suspended matters, has lower suspended matters entering a membrane tank compared with other sewage treatment devices and processes, and has the concentration of the suspended matters in the membrane tank which is one tenth or lower than that of the suspended matters in the MBR process, so that the membrane module is not easy to block, the chemical cleaning period of the membrane module is prolonged, the dosage of the medicament is reduced, and the service life of the membrane module is prolonged due to the reduction of the chemical cleaning frequency and the dosage of the medicament, thereby reducing the replacement cost of the membrane module and saving the operation cost of the system.

(4) Compared with an MBR sewage treatment device and process, the sludge reflux system is not arranged in the invention, but the reflux from the membrane tank to the sludge-water separation tank is arranged, and the reflux flow is 200-300% lower than that of the sludge in the MBR process, so that the sludge reflux energy consumption is saved, and the operation cost can be further reduced by the membrane tank.

(5) Because the amount of suspended sludge in the membrane tank is low, in order to ensure the membrane flux of the membrane component and prevent membrane blockage, the bottom of the membrane tank is additionally provided with the aeration component which can be used for generating aeration bubbles, and the aeration bubbles collide with the membrane component to make suspended matters adhered on the membrane component fall off on the membrane component and be used for cleaning the membrane component.

(6) The sewage treatment device of the biofilm reactor can resist impact load, and when the sewage treatment of the biofilm reactor is impacted, the quality of the effluent can still be kept stable.

(7) The biomembrane reactor sewage treatment device has high oxygen transmission rate, the oxygen transmission rate in the improved biomembrane reactor is twice of that of the MBBR reactor, and the energy consumption of a fan is saved; the operation cost is reduced.

(8) The sewage treatment device of the biofilm reactor adopts a modular design, and is convenient to transport and install on site as a whole.

(9) The sewage treatment device of the biofilm reactor is simple in operation and management and simple in integral structure, can reduce the occupied area, saves the civil engineering cost and is convenient to use.

The invention is further illustrated with reference to the following figures and examples.

Drawings

FIG. 1 is a schematic diagram of the overall structure of an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an improved biofilm reactor in an embodiment of the invention;

FIG. 3 is a schematic structural diagram of a membrane tank in an embodiment of the present invention.

In the figure: 1-improved biofilm reactor; 101-a denitrification tank; 102-an aerobic tank; 103-a post-denitrification pool; 104-suspended fillers; 105-a main water inlet pipeline; 106-internal circulation pump; 107-emptying pipeline; 108-emptying the screen; 109-a blow-down valve; 110-intercepting screen; 111-a stirring device; 2-an aeration system; 201-a first aeration fan; 202-gas transmission pipeline; 203-an aerator pipe; 204-a second aeration fan; 205-air supply line; 206-membrane tank aeration pipe; 3-a membrane tank; 301-a flushing assembly; 4-a membrane module; 5-a mud-water separation unit; 501-supernatant liquid water conveying pipeline; 502-sludge discharge pipe; 6-reflux pump; 601-concentrated water suction line; 602-concentrated water conveying pipeline; 7-water outlet pipeline; 701-a phosphorus removing agent feeding device; 712-a chemical reaction tank; 8-a carbon source feeding device; 9-a vacuum pump; 10-flush water return line.

Detailed Description

Example (b): referring to fig. 1-3, a biofilm reactor sewage treatment plant comprises an improved biofilm reactor 1, wherein the improved biofilm reactor 1 is provided with an aeration system 2, a stirring device 111, a suspended filler 104 and a screen; the improved biofilm reactor 1 is characterized in that the water outlet end of the improved biofilm reactor 1 is communicated with a membrane pool 3, a membrane component 4 is arranged in the membrane pool 3, a mud-water separation unit 5 is arranged between the membrane pool 3 and the improved biofilm reactor 1, the mud-water separation unit 5 is communicated with the membrane pool 3 through a reflux pump 6, the reflux pump 6 is used for conveying sludge and sewage in the membrane pool 3 to the mud-water separation unit 5, and supernatant obtained after the sludge is separated by the mud-water separation unit 5 flows back into the improved biofilm reactor 1 through gravity.

The improved biomembrane reactor 1 comprises a tank body, wherein at least one stage of denitrification tank 101 and at least one stage of aerobic tank 102 are sequentially arranged in the tank body according to the treatment trend of sewage, the water outlet end of the aerobic tank 102 is communicated with a post-positioned denitrification tank 103, and the last stage of aerobic tank 102 is communicated with the denitrification tank 101 through a sewage circulating pipeline.

The denitrification tank 101, the aerobic tank 102 and the post-positioned denitrification tank 103 are respectively filled with suspended fillers 104.

The suspended filler 104 in the denitrification tank 101 is attached with facultative microorganisms such as denitrifying bacteria, nitrifying bacteria, yeast, protozoa, metazoans and the like, the filling amount of the suspended filler 104 in the denitrification tank 101 is 60-80%, the specific gravity is 0.96-0.98, and the specific surface area is 300-800 m²/m³。

Aerobic microorganisms such as bacteria, fungi, protozoa and metazoan are attached to the suspended filler 104 in the aerobic tank 102, the filling amount of the suspended filler 104 in the aerobic tank 102 is 60-80%, the specific gravity is 0.96-0.98, and the specific surface area is 300-800 m²/m³。

The denitrification tank 101, the aerobic tank 102 and the post-denitrification tank 103 are respectively communicated in sequence, and the liquid levels in the denitrification tank 101, the aerobic tank 102 and the post-denitrification tank 103 are gradually reduced in sequence, so that the sewage to be treated in the denitrification tank 101, the aerobic tank 102 and the post-denitrification tank 103 flows in sequence through gravity flow.

The stirring devices 111 are respectively arranged in the denitrification tank 101 and the post-denitrification tank 103 of the improved biofilm reactor 1.

Agitating unit 111 is prior art, and its concrete structure includes agitator motor, (mixing) shaft and stirring vane, agitator motor output power drive (mixing) shaft drives stirring vane and rotates, agitating unit 111 is used for stirring the suspended filler 104 in denitrification pond 101 and the rearmounted denitrification pond 103.

The denitrification tank 101 is communicated with external sewage to be treated through a main water inlet pipeline 105, the sewage enters the denitrification tank 101, and then the sewage in the denitrification tank 101 automatically flows into the aerobic tank 102 and the post-denitrification tank 103 in sequence through gravity flow.

After the sewage enters the denitrification tank 101, the sewage can be adjusted through the denitrification tank 101, and the facultative microorganisms in the denitrification tank 101 are used for treating the sewage.

Then the sewage treated in the denitrification tank 101 automatically flows into the aerobic tank 102 through gravity flow, and aerobic microorganisms in the aerobic tank 102 are used for converting ammonia nitrogen in the sewage into nitrate nitrogen and simultaneously reducing COD in the water.

At the moment, the sewage treated in the aerobic tank 102 flows back to the denitrification tank 101 through a sewage circulating pipeline, and the facultative microorganisms in the denitrification tank 101 are used for converting nitrate nitrogen in the sewage into nitrogen, so that the purpose of reducing total nitrogen is achieved.

And the sewage treated in the aerobic tank 102 automatically flows into the post-positioned denitrification tank 103 for further treatment through gravity flow, so that the sewage treatment effect is improved.

The whole shape of the suspended filler 104 in the denitrification tank 101, the aerobic tank 102 and the post-denitrification tank 103 is cylindrical, and a plurality of through holes are formed in the suspended filler.

The suspended filler 104 in the denitrification tank 101, the aerobic tank 102 and the post-denitrification tank 103 all form a micro-reactor, thereby improving the degradation effect on pollutants in the sewage.

And the biomembrane on the suspended filler 104 can be used for adsorbing and degrading organic matters in the sewage to purify the water quality, and the improved biomembrane reactor 1 has no blocking phenomenon, and can realize backwashing with less power.

The sewage circulating pipeline comprises an inner circulating pump 106, a water inlet of the inner circulating pump 106 is communicated with the aerobic tank 102 through a water inlet pipe, and a water outlet of the inner circulating pump 106 is communicated with the denitrification tank 101 through a water outlet pipe.

By the design, the sewage treated in the aerobic tank 102 can be sucked by the internal circulating pump 106, the sewage sucked by the internal circulating pump in the aerobic tank 102 is conveyed into the denitrification tank 101 through the water outlet pipe, and the facultative microorganisms in the denitrification tank 101 are used for converting nitrate nitrogen in the sewage into nitrogen, so that the purpose of reducing total nitrogen is achieved.

In this embodiment, the denitrification tank 101, the aerobic tank 102 and the post-denitrification tank 103 are communicated in sequence.

In addition to this embodiment, there may be a plurality of aerobic tanks 102, and the plurality of aerobic tanks 102 are respectively and sequentially communicated, and the use of the post-denitrification tank 103 may be eliminated according to the water quality requirement.

The aeration system 2 comprises a first aeration fan 201, the air outlet of the first aeration fan 201 is communicated with two groups of air pipelines 202, and the air pipelines 202 are respectively communicated with aeration pipes 203 in the denitrification tank 101 and the aerobic tank 102.

The first aeration fan 201 generates wind power after being started, and the wind power is conveyed into the aeration pipe 203 in the aerobic tank 102 through the air conveying pipeline 202, at the moment, the aeration pipe 203 in the aerobic tank 102 aerates the aerobic tank 102, so that the suspended filler 104 in the aerobic tank 102 can enable a biological film on the surface of the suspended filler 104 to adsorb a large amount of organic pollutants in the sewage under the action of aeration and water flow lifting, and the pollutants are decomposed and metabolized for treating the sewage to purify the sewage.

An electromagnetic switch valve is serially arranged on a communication pipeline between the gas pipeline 202 and the aeration pipe 203 in the denitrification tank 101 and is used for controlling whether the gas pipeline 202 supplies gas to the aeration pipe 203 in the denitrification tank 101.

By the design, when the denitrification tank 101 is used for normally treating wastewater, the electromagnetic switch valve is closed to cut off the communication between the gas pipeline 202 and the aeration pipe 203 in the denitrification tank 101, and the aeration pipe 203 in the denitrification tank 101 does not output aeration at the moment;

when the denitrification tank 101 needs forward flushing, the electromagnetic switch valve is opened to communicate the air pipeline 202 with the aeration pipe 203 in the denitrification tank 101, at the moment, the wind power generated by the first aeration fan 201 is conveyed into the aeration pipe 203 in the denitrification tank 101 through the air pipeline 202, at the moment, the aeration pipe 203 aerates the inside of the denitrification tank 101 to enable the suspended filler 104 to move actively, so that the attachments on the suspended filler 104 are flushed forward, and the use is convenient.

The first aeration fan 201 is a variable frequency fan, and the air quantity of the first aeration fan 201 can be adjusted according to the water inlet water quality, so that the aeration quantity is adjusted, and the DO content in the tank is ensured to be 2-3 mg/L.

The material of aeration pipe 203 is 304L stainless steel or UPVC material, can prolong aeration pipe 203's life, improves the result of use.

The water outlets of the denitrification tank 101, the aerobic tank 102 and the post-denitrification tank 103 are respectively provided with an interception screen 110, and the interception screens 110 are used for intercepting the suspended fillers 104 in the tanks to prevent the suspended fillers 104 from entering the next stage.

An emptying pipeline 107 is arranged below the improved biofilm reactor 1, and an emptying screen 108 is arranged in the improved biofilm reactor 1 at the emptying pipeline 107.

An air release valve 109 is connected in series on the air release pipeline 107, and the air release valve 109 is used for controlling the on-off of the air release pipeline 107.

And a carbon source feeding device 8 for feeding a carbon source into the improved biofilm reactor 1 is arranged above the improved biofilm reactor 1.

Carbon sources are stored in the carbon source feeding device 8, the carbon source feeding device 8 is used for feeding carbon sources into the improved biofilm reactor 1, and denitrifying bacteria in the carbon source improved biofilm reactor 1 provide required nutrients, so that the denitrification efficiency is improved, and the total nitrogen removal effect is enhanced.

The water outlet of the improved biomembrane reactor 1 is communicated with the membrane tank 3 through a water outlet pipeline 7, a chemical reaction tank 702 is connected in series on the water outlet pipeline 7 between the improved biomembrane reactor 1 and the membrane tank 3, and a phosphorus removing agent feeding device 701 is arranged on the chemical reaction tank 702.

The phosphorus removal agent feeding device 701 stores a phosphorus removal agent, wastewater after biochemical treatment and output from a water outlet of the improved bio-membrane reactor 1 is conveyed into the chemical reaction tank 702 through the water outlet pipeline 7, at the moment, the phosphorus removal agent feeding device 701 works to convey the phosphorus removal agent into the chemical reaction tank 702 and mix the phosphorus removal agent with the wastewater to remove phosphorus from the wastewater and improve the sewage treatment effect, and then the effluent of the chemical reaction tank 702 is conveyed into the membrane tank 3 through the water outlet pipeline 7.

In this embodiment, the chemical reaction tank 702 and the phosphorus removing agent feeding device 701 are selectively installed, and whether the chemical reaction tank 702 and the phosphorus removing agent feeding device 701 are installed or not can be selected according to the characteristics of the wastewater to be treated.

The water outlet of the improved biofilm reactor 1 is communicated with the membrane tank 3 through the water outlet pipeline 7, the improved biofilm reactor 1 is used for removing organic matters in sewage, reducing the sludge concentration in the sewage entering the membrane tank 3, further reducing the cleaning times of the membrane component 4 and prolonging the service life of the membrane component 4.

The aeration component is arranged outside the membrane tank 3 and comprises a second aeration fan 204, the air outlet end of the second aeration fan 204 is communicated with an air supply pipeline 205, the air supply pipeline 205 is communicated with a membrane tank aeration pipe 206, and the membrane tank aeration pipe 206 is arranged at the bottom of the membrane tank 3.

The second aeration fan 204 generates high-pressure gas after being started, and the high-pressure gas is respectively conveyed into the membrane tank 3 through the air supply pipeline 205, at the moment, aeration bubbles can collide with the membrane assembly 4, so that suspended matters adhered to the membrane assembly 4 fall off from the membrane assembly 4 for cleaning the membrane assembly 4, the service cycle of the membrane assembly 4 is further prolonged, the cleaning times of the membrane assembly 4 are reduced, and the service life of the membrane assembly 4 is prolonged.

The second aeration fan 204 is a variable frequency fan, and the air volume of the second aeration fan 204 can be adjusted according to the water quality of the inlet water, so that the aeration volume can be adjusted.

The membrane tank aeration pipe 206 is made of 304L stainless steel or UPVC material, so that the service life of the membrane tank aeration pipe 206 can be prolonged, and the use effect can be improved.

The air outlet end of the second aeration fan 204 can also be communicated with an air supply branch pipe, the air supply branch pipe is communicated with an aeration pipe in the rear denitrification tank 103, and the second aeration fan 204 works to aerate the rear denitrification tank 103 through the air supply branch pipe and the aeration pipe.

And the air supply branch pipes are connected in series with electromagnetic switch valves which are used for controlling whether the air supply branch pipes are communicated or not.

By the design, when the post-denitrification tank 103 is in normal wastewater treatment, the electromagnetic switch valve is closed to cut off the air supply branch pipe, and the aeration pipe in the post-denitrification tank 103 does not output aeration;

when the rear denitrification tank 103 needs to be washed forwards, the electromagnetic switch valve is opened to communicate the air supply branch pipe, and at the moment, the second aeration fan 204 works to aerate the rear denitrification tank 103 through the air supply branch pipe and the aeration pipe, so that the suspended filler 104 in the rear denitrification tank 103 moves actively, and the suspended filler 104 is used for washing the attachments on the suspended filler 104 forwards, and the use is convenient.

This forward flushing is so called because the feed water is continuously fed into the reactor during the flushing and is effectively treated.

And a flushing assembly 301 for back flushing the membrane assembly 4 is arranged on the membrane tank 3, and an acid washing solution and an alkali washing solution are stored in the flushing assembly 301.

The flushing assembly 301 is operative for delivering an acid wash and a base wash to the membrane modules 4 of the membrane tank 3 for back flushing the membrane modules 4.

By the design, the sewage purified by the improved biomembrane reactor 1 is conveyed into the membrane tank 3 through the outlet screen and the water outlet pipeline 7, the sewage in the membrane tank 3 is subjected to solid-liquid separation under the action of the membrane component 4, and the filtered filtrate is discharged after removing suspended matters.

The water outlet of the membrane tank 3 is communicated with a vacuum pump 9, and the vacuum pump 9 is used for outputting filtrate which is obtained by performing solid-liquid separation on the membrane module 4 in the membrane tank 3.

The inlet intercommunication of backwash pump 6 has dense water suction pipeline 601, the one end that reflux pump 6 was kept away from to dense water suction pipeline 601 extends to in the membrane cisterna 3 and is close to the bottom of the pool of membrane cisterna 3, the liquid outlet intercommunication of backwash pump 6 has dense water conveying pipeline 602, the other end and the mud-water separation unit 5 intercommunication of dense water conveying pipeline 602.

By means of the design, power is output by the reflux pump 6, the concentrated sludge water at the position close to the membrane tank 3 can be sucked by the concentrated sludge water suction pipeline 601, and is conveyed to the sludge-water separation unit 5 by the concentrated sludge water conveying pipeline 602, and the sludge-water separation unit 5 is used for performing solid-liquid separation on the concentrated sludge water and separating sludge in the concentrated sludge water.

The water outlet end of the mud-water separation unit 5 is communicated with a supernatant water conveying pipeline 501, and one end of the supernatant water conveying pipeline 501, which is far away from the mud-water separation unit 5, is communicated with the aerobic tank 102 of the improved biofilm reactor 1.

The liquid level in the mud-water separation unit 5 is higher than the liquid level of the aerobic tank 102 of the improved biofilm reactor 1, and the liquid level in the mud-water separation unit 5 is lower than the liquid level of the denitrification tank 101 of the improved biofilm reactor 1.

By the design, the sludge-water separation unit 5 can separate sludge concentrated water into supernatant after solid-liquid separation, the liquid level in the sludge-water separation unit 5 is higher than that in the aerobic tank 102, the supernatant in the sludge-water separation unit 5 enters the supernatant water conveying pipeline 501 under the action of gravity flow, and then automatically flows into the aerobic tank 102 under the guidance of the supernatant water conveying pipeline 501 to positively flush the suspended filler 104 in the aerobic tank 102.

And the flushing water in the aerobic tank 102 flows back to the denitrification tank 101 under the action of the internal circulation pump 106 to flush the suspended filler 104 in the denitrification tank 101 in the forward direction, so that the sludge concentration in the improved biofilm reactor 1 can be greatly reduced.

And the supernatant in the mud-water separation unit 5 automatically flows into the aerobic tank 102 by the gravity flow and the guidance of the supernatant water pipeline 501, and the supernatant is conveyed without a power assembly, so that the power energy consumption is not needed, and the operation cost is greatly reduced.

The sludge precipitated in the membrane tank 3 is conveyed into the mud-water separation unit 5 through the concentrated water suction pipeline 601, the reflux pump 6 and the concentrated water conveying pipeline 602, solid-liquid separation is carried out, so that the sludge in the concentrated sludge is separated, and further a small amount of sludge precipitated in the membrane tank 3 does not flow back, so that the sludge concentration in the whole system is reduced, the cleaning times of the membrane component 4 can be reduced, and the service life of the membrane component 4 is prolonged.

A liquid outlet of a denitrification tank 101 of the improved biomembrane reactor 1 is communicated with a flushing water return pipeline 10, one end, far away from the denitrification tank 101, of the flushing water return pipeline 10 is communicated with a mud-water separation unit 5, and flushing water in the denitrification tank 101 flows back to the mud-water separation unit 5 through gravity flow and the flushing water return pipeline 10.

By the design, the washing water in the denitrification tank 101 can flow back to the mud-water separation unit 5 through the gravity flow and the washing water return pipeline 10, the mud-water separation unit 5 performs solid-liquid separation on the washing water to separate suspended matters in the washing water, so that the sludge concentration and sludge age in the improved biofilm reactor 1 can be greatly reduced, the sludge concentration in the sewage which is treated by the improved biofilm reactor 1 and is conveyed to the membrane tank 3 is low, the cleaning frequency of the membrane module 4 can be reduced, and the service life of the membrane module 4 is prolonged.

The sludge outlet of the sludge-water separation unit 5 is communicated with a sludge discharge pipe 502, and the sludge separated in the sludge-water separation unit 5 is conveyed outwards through the sludge discharge pipe 502.

Due to the design, the sludge obtained after solid-liquid separation in the sludge separation unit 5 is conveyed into the sludge discharge pipe 502, the sludge discharge pipe 502 conveys the sludge outwards for outward transportation treatment, so that the sludge in the sewage treatment device of the integral biofilm reactor does not flow back, the concentration of the sludge in the membrane tank 3 is reduced, the treatment difficulty of the membrane module 4 is reduced, the cleaning frequency of the membrane module 4 can be reduced, and the service life of the membrane module 4 is prolonged.

The mud separation unit 5 is one or a combination of a sloping plate sedimentation tank, a mud concentration tank and a mud separator.

Referring to fig. 1-3, the invention discloses a biofilm reactor sewage treatment method based on the biofilm reactor sewage treatment device, and the treatment method specifically comprises the following steps:

s1, the sewage to be treated enters an improved biofilm reactor 1 through a main water inlet pipeline 105, a suspended filler 104 is filled in the improved biofilm reactor 1, a biofilm grows on the surface of the suspended filler 104, the sewage firstly enters a denitrification tank 101 of the improved biofilm reactor 1, the sewage in the denitrification tank 101 is mixed with a nitrifying liquid flowing back from an aerobic tank 102, a part of total nitrogen in the sewage is removed through denitrification, and a part of BOD is removed at the same time₅And CODcr, reducing the subsequent treatment load of the aerobic tank 102.

S2, the effluent of the denitrification tank 101 automatically flows into the aerobic tank 102 by gravity, the organic pollutants in the sewage are degraded under the action of aerobic microorganisms, and the BOD contained in the sewage is removed by oxidative decomposition and anabolism₅And CODcr and ammonia nitrogen, purifying the sewage, feeding part of the effluent treated by the aerobic tank 102 into a subsequent process, returning part of the effluent to the denitrification tank 101 through an internal circulating pump 106, and adjusting the flow of the internal circulating pump according to the carbon-nitrogen ratio of the inlet water and the total nitrogen concentration of the outlet water.

S3, under the conditions that the carbon-nitrogen ratio of inlet water is lower than 3.5 and the TN concentration requirement of outlet water is high, the outlet water of the aerobic tank 102 enters the post-denitrification tank 103, and NO contained in the sewage is treated by denitrifying bacteria in the post-denitrification tank 103₃And N is converted into nitrogen to be removed, the total nitrogen content is further reduced, the effluent quality is ensured to reach the standard, and the carbon source feeding device 8 works to provide a carbon source required by post denitrification for the improved biomembrane reactor 1, so that the denitrification is ensured to be normally carried out.

In the step S3, if the carbon-nitrogen content of the inlet water is higher than 3.5, the outlet water of the aerobic tank 102 can directly enter the membrane tank 3.

S4, enabling the sewage subjected to three-stage or multi-stage treatment by the improved bio-membrane reactor 1 to enter a water outlet pipeline 7, connecting a phosphorus removing agent feeding device 701 to the water outlet pipeline 7, feeding a phosphorus removing agent by the phosphorus removing agent feeding device 701 and mixing the phosphorus removing agent with the sewage in the water outlet pipeline 7 to remove phosphate in the sewage, then enabling the sewage to enter a membrane pool 3 together, and further performing biochemical treatment and physical filtration on the sewage subjected to the biochemical treatment in the membrane pool 3 through a membrane component 4, wherein the physical filtration is realized in the membrane component by vacuumizing through a vacuum pump; suspended matters and turbidity in the effluent water separated by the membrane module 4 are close to zero, and bacteria and viruses are greatly removed, so that the discharge requirement is met.

The sludge separated and separated by the membrane module 4 in the step S4 is sent to the sludge-water separation unit 5 by the reflux pump 6.

In the step S4, an aeration pipeline is installed at the bottom of the membrane tank 3, aeration is performed by the second aeration fan 204, the surface of the membrane module 4 is washed away, the membrane blockage speed is slowed down, chemical deep cleaning is periodically performed on the biological membrane module by the washing module, and a higher membrane flux rate is further maintained.

S5, conveying the sludge in the membrane tank 3 to the mud-water separation unit 5 through the reflux pump 6, performing solid-liquid separation in the mud-water separation unit 5, discharging the sludge generated by bottom concentration after solid-liquid separation through the sludge discharge pipe 502, performing subsequent treatment, and returning the supernatant obtained at the upper part in the mud-water separation unit 5 to the aerobic tank 102 through the supernatant water conveying pipeline 501 for biochemical treatment.

In the step S5, the sludge-water separation unit 5 is backwashed at regular intervals by the effluent of the denitrification tank 101, and the whole backwashing process is completed by the liquid level difference between the denitrification tank 101 and the sludge-water separation unit 5, so that power is not consumed, and energy consumption is saved.

By adopting the technical scheme, the improved biomembrane reaction treatment process and the membrane treatment process can be combined, the treatment effect on sewage is improved, the sewage to be treated firstly enters the improved biomembrane reactor for biochemical treatment, so that organic pollutants in the sewage are decomposed and metabolized in the improved biomembrane reactor, the concentration of the organic pollutants in the sewage entering a subsequent membrane pool is very low, the pollution to the membrane component is further reduced, the service life of the membrane component is prolonged, the operation cost is reduced, the biomass concentration in the improved biomembrane reactor is high, the volume load is high, the occupied area is greatly reduced, suspended matters in water are intercepted by the membrane component, the effluent quality is good, the subsequent structures such as a secondary sedimentation tank are saved, the occupied area is further reduced, and the civil engineering cost is saved.

It will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in the embodiments described above without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims.

Claims

1. A sewage treatment device of a biofilm reactor is characterized in that: the improved biological membrane reactor comprises an improved biological membrane reactor (1), wherein an aeration system (2), a stirring device (111), a suspended filler (104) and a screen are respectively arranged on the improved biological membrane reactor (1), the water outlet end of the improved biological membrane reactor (1) is communicated with a membrane pool (3), a membrane component (4) is arranged in the membrane pool (3), a mud-water separation unit (5) is arranged between the membrane pool (3) and the improved biological membrane reactor (1), the mud-water separation unit (5) is communicated with the membrane pool (3) through a reflux pump (6), the reflux pump (6) is used for conveying sludge and sewage in the membrane pool (3) to the mud-water separation unit (5), and supernatant obtained after the sludge is separated by the mud-water separation unit (5) flows back into the improved biological membrane reactor (1) through gravity.

2. A biofilm reactor wastewater treatment plant according to claim 1, wherein: the improved biomembrane reactor (1) comprises a tank body, wherein at least one stage of denitrification tank (101) and at least one stage of aerobic tank (102) are sequentially arranged in the tank body according to the treatment trend of sewage, the water outlet end of the aerobic tank (102) is communicated with a post-positioned denitrification tank (103), and the last stage of aerobic tank (102) is communicated with the denitrification tank (101) through a sewage circulating pipeline.

3. A biofilm reactor wastewater treatment plant according to claim 2, wherein: the denitrification tank (101), the aerobic tank (102) and the post-positioned denitrification tank (103) are respectively filled with suspended fillers (104), the filling amount of the suspended fillers (104) in each tank is 60-80%, the specific gravity is 0.96-0.98, and the specific surface area is 300-800 m²/m³。

4. A biofilm reactor wastewater treatment plant according to claim 3, wherein: the sewage circulating pipeline comprises an internal circulating pump (106), a water inlet of the internal circulating pump (106) is communicated with the aerobic tank (102) through a water inlet pipe, and a water outlet of the internal circulating pump (106) is communicated with the denitrification tank (101) through a water outlet pipe.

5. The biofilm reactor wastewater treatment plant of claim 4, wherein: the water outlet of the improved biomembrane reactor (1) is communicated with the membrane tank (3) through a water outlet pipeline (7), a chemical reaction tank (702) is connected in series on the water outlet pipeline (7), and a phosphorus removing agent feeding device (701) is arranged on the chemical reaction tank (702).

6. The biofilm reactor wastewater treatment plant of claim 5, wherein: an aeration component is arranged outside the membrane tank (3), the aeration component conveys high-pressure gas into the membrane tank (3) and is used for colliding the membrane component (4) to clean the membrane component (4), and a flushing component (301) for flushing the membrane component (4) is arranged on the membrane tank (3).

7. The biofilm reactor wastewater treatment plant of claim 6, wherein: the liquid level in the mud-water separation unit (5) is higher than the liquid level of the aerobic pool (102), and the water outlet end of the mud-water separation unit (5) is communicated with the aerobic pool (102) through a supernatant water conveying pipeline (501).

8. A biofilm reactor wastewater treatment plant according to claim 7, wherein: the liquid level in the mud-water separation unit (5) is lower than that of the denitrification tank (101), the liquid outlet of the denitrification tank (101) is communicated with the denitrification tank (101) through a washing water return pipeline (10), and washing water in the denitrification tank (101) flows back to the mud-water separation unit (5) through gravity flow and the washing water return pipeline (10).

9. A sewage treatment method of a biofilm reactor is characterized in that: a biofilm reactor wastewater treatment plant according to any of claims 1 to 8, the treatment process comprising in particular the steps of:

s1, the sewage to be treated enters a denitrification tank (101) through a main water inlet pipeline (105), the sewage in the denitrification tank (101) is mixed with the nitrified liquid flowing back from the aerobic tank (102), part of total nitrogen in the sewage is removed through denitrification, and part of BOD is removed simultaneously₅And CODcr;

s2, the effluent of the denitrification tank (101) automatically flows into the aerobic tank (102) by gravity, and the organic pollutants in the sewage are degraded under the action of aerobic microorganisms to remove BOD contained in the sewage₅CODcr and ammonia nitrogen, wherein part of the effluent treated by the aerobic tank (102) enters the subsequent process, and the other part of the effluent returns to the denitrification tank (101) through an internal circulating pump (106);

s3, under the conditions that the carbon-nitrogen ratio of inlet water is lower than 3.5 and the requirement on the total nitrogen concentration of outlet water is high, outlet water of an aerobic tank (102) enters a post-denitrification tank (103), ammonia nitrogen contained in sewage is converted into nitrogen to be removed under the action of denitrifying bacteria, and a carbon source feeding device (8) works to provide a carbon source required by post-denitrification and ensure that denitrification is normally carried out;

s4, feeding the sewage treated by the improved bio-membrane reactor (1) into a water outlet pipeline (7), feeding a phosphorus removing agent into a phosphorus removing agent feeding device (701) for removing phosphate in the sewage, then feeding the sewage into a membrane pool (3), and performing further biochemical treatment and physical filtration on the sewage subjected to the biochemical treatment by a membrane module (4);

s5, conveying the sludge part in the membrane tank (3) to a mud-water separation unit (5) through a reflux pump (6) for solid-liquid separation, obtaining sludge and supernatant after the solid-liquid separation, discharging the sludge through a sludge discharge pipe (502), and returning the supernatant to the aerobic tank (102) through a supernatant water conveying pipeline (501) for biochemical treatment.

10. The biofilm reactor wastewater treatment method of claim 9, wherein: and S4, conveying the sludge separated by the membrane module (4) to a sludge-water separation unit (5) through a reflux pump (6), and aerating the membrane tank (3) by an aeration module of the membrane tank (3) for flushing the surface of the membrane module (4).