291 results about "Backwashing" patented technology

The utility model relates to water purification technical field discloses a big flow ultrafiltration membrane water purifier with self -cleaning and backwash function, including prefilter and two or more than two parallel connection's ultrafiltration membrane water purifier, water purifier purifying water export is equipped with the three ways, and the three ways are connected with the loose joint and become two water purifier's purifying water cavity intercommunication, and the water inlet and sewage water mouth of water purifier are equipped with control valve and three ways, and the three ways are connected with the loose joint and become water inlet channel and sewage water channel respectively, through closing or opening corresponding water inlet control valve and sewage water control valve, the purifying water of water purifier automatic backwash is carried out to the filter core of another water purifier, and backwash is crossed and is carried out between two or more than two water purifiers, and sewage water pipeline communication is often used water's wash vegetables pool, mop pool, such as toilet equipment, and the function of backwash and sewage water at any time is superimposed, makes filter core more clean, if maintaining properly, the service life of water purifier filter core reaches at least ten years or more.

This invention discloses a method and system for purifying and treating release agents, belonging to the field of release agent purification and treatment. The treatment method is as follows: S1, raw release agent wastewater is introduced into a treatment tank for hydraulic cavitation treatment, while ozone is simultaneously introduced. Floating oil, waste wax, and solid particulate matter in the wastewater float to the surface of the treatment tank and overflow into a scum tank; S2, after cavitation treatment, when there is very little scum on the surface of the treatment tank, the treated liquid in the treatment tank is introduced into a media filter for further filtration. The filtered clean liquid is then transported to a supply tank; S3, when the media packing adsorbs a thick wax layer, the pressure in the filter tank reaches a threshold. Water from the circulating water tank is introduced into the filter tank to backwash the wax layer. The water containing wax after backwashing enters the circulating water tank; S4, when the wax content in the circulating water in the circulating water tank reaches a threshold, a low-temperature steel roller is used to cool the water, causing wax to precipitate onto the steel roller. The wax is scraped off and collected, and the water is reused. This invention uses hydraulic cavitation to break out and remove oil and wax from waste liquid, and further removes residual waste wax from the treated liquid through media filtration, ensuring the cleanliness of the recycled mold release agent liquid.

The invention provides a direct water purification system with an automatic backwashing function, which comprises a raw water inlet part, a first pressure valve, a filtering device, a second pressure valve, a purified water outlet part, a waste water outlet part and an energy recovery waterway, and the energy recovery waterway is in liquid communication with the filtering device, the second pressure valve and the first pressure valve. Wherein the energy recovery waterway is configured to accumulate the purified water to accumulate pressure when the purified water outlet part is closed, and to reversely flow the purified water to the filtering water outlet through the accumulated pressure to clean the filtering assembly. The direct-delivery water purification system with the automatic backwashing function is suitable for automatically cleaning the direct-delivery water purification system after purified water is used and output every time.

The present application relates to the technical field of filtration and discloses a raw water filter, which comprises a tank body, a first hole plate and a second hole plate, a fiber bundle assembly, a driving assembly and a flushing assembly, the first hole plate and the second hole plate are arranged in the tank body in a direction along a central axis of the tank body and are spaced apart from each other, a filter chamber is formed at the spacing, the driving assembly is used for driving the first hole plate to move reciprocally along a height direction of the tank body and to rotate around the central axis of the tank body, the fiber bundle assembly is arranged between the first hole plate and the second hole plate, and rotation and / or movement of the first hole plate can cause the fiber bundle assembly to deform so as to change a porosity of the fiber bundle assembly, and the flushing assembly is used for spraying cleaning medium to clean impurities on the fiber bundle assembly. The raw water filter of the embodiment of the present application realizes further compression and stretching of the fiber bundle during filtration and backwashing, and improves filtration effect and self-cleaning effect.

The utility model discloses a kind of pressure tank reverse washing water purification equipment, it includes: shell, the inner wall of shell is fixedly connected with water purification tank, the inner wall of water purification tank is fixedly connected with water inlet pipe, the inner wall of water purification tank is fixedly connected with filter screen, reverse osmosis membrane and several filter core, the inner wall of shell is fixedly connected with storage tank, the inner wall of storage tank is fixedly connected with connecting pipe, the inner wall of storage tank is fixedly connected with water outlet pipe;The inner wall of water purification tank is fixedly connected with flushing pipe, flushing nozzle, first flushing pump, second flushing pump, first drainage device and second drainage device, the inner wall of water purification tank is rotatably connected with change road board, the inner wall of water purification tank is fixedly connected with water purification chamber and wastewater chamber, the inner wall of wastewater chamber is fixedly connected with wastewater pipe.Through above-mentioned structure, accurate individual flushing can be carried out to filter water purification assembly according to need, can save purified water resource used in backwashing cleaning, while also can prevent filter core from being damaged due to flushing, prolong the service life of water purifier.

The utility model provides a kind of shrimp pond bottom sewage system, it is related to aquaculture equipment technical field, including bucket shell and rotary filter assembly, its inside is provided with basin, and basin is enclosed to form filter chamber, and basin is enclosed with bucket shell to form backwashing chamber;Rotary filter assembly includes rotatably being arranged in the drum of the basin, and the circumferential surface of the drum is equipped with mesh hole;Wherein, the filter chamber is communicated with backwashing chamber by the mesh hole;When sewage enters filter chamber, it is guided to backwashing chamber discharge by the mesh hole;When mesh hole is blocked, drive the drum rotates predetermined angle, so that blocked mesh hole turns into backwashing chamber and carries out hydraulic self-cleaning.The utility model has the beneficial effect that the isolation effect of drum to fish and shrimp, the rotation function of drum can also realize hydraulic self-cleaning, can effectively solve mesh hole blockage problem, without frequent cleaning by hand, reduce maintenance cost and manpower investment, improve sewage efficiency.

The application relates to the field of membrane products and relates to a filter membrane backwashing service life determination method. The method comprises the following steps: backwashing a filter membrane under n different backwashing pressures, measuring n first backwashing times corresponding to the n different backwashing pressures and capable of being tolerated by the filter membrane; performing mathematical model fitting on the n backwashing pressures and the n backwashing times, establishing a function relationship between the backwashing pressure and the backwashing time; backwashing the filter membrane under the n different backwashing pressures in a pilot environment, measuring n second backwashing times corresponding to the n different backwashing pressures; comparing each first backwashing time with each second backwashing time to obtain a deviation; determining the backwashing service life of the filter membrane by using the function relationship and the deviation; and n is greater than or equal to 3. The service life is predicted by testing the actual backwashing times of the filter membrane under any pressure value.

This invention discloses an application device and method for high-efficiency, anti-fouling MBR membrane modules in wastewater treatment. The MBR tank of this device employs special materials and structural design, resulting in a reasonable hydraulic retention time. The MBR membrane module is made of modified PVDF, with precisely controlled membrane pore size and reinforced ribs and a unique encapsulation structure. Combined with an aeration device featuring a central aeration nozzle, it effectively solves problems such as membrane breakage, entanglement, and aeration dead zones. It is also equipped with comprehensive supporting equipment, and automated operation and precise control are achieved through an online monitoring and control system. The application method covers steps including biological wastewater treatment, membrane filtration, air scrubbing, backwashing, and chemical cleaning, and maintenance and optimization are performed based on water quality and equipment conditions. This invention significantly improves wastewater treatment efficiency and water quality stability, reduces membrane fouling and operating costs, extends membrane module lifespan, is highly adaptable, and offers intelligent and simple operation, providing an innovative and efficient solution for wastewater treatment.

This invention discloses a valve for easy cleaning and sewage discharge, and its usage method. The valve body includes an inlet and an outlet, and also has a through-hole. The inlet is connected to the outlet via the through-hole. A valve core, slidably connected to the valve body, is located above the through-hole. A main shaft is movably mounted on the valve body, with a handwheel connected to its upper end after passing through the valve body. A first gear is fixedly mounted on the bottom end of the main shaft. A second gear, cooperating with the first gear, is rotatably connected to the valve body and threadedly connected to the valve core. A filter screen is installed inside the through-hole. A rotating rod is movably mounted inside the valve core, with a brush fixedly connected to its bottom end below the filter screen. A third gear, cooperating with the first gear, is fixedly connected to the upper end of the rotating rod. This device can clean the filter screen inside the valve, and the included backwashing channel allows for backwashing of the filter screen, facilitating the discharge of impurities from the valve.

This utility model belongs to the technical field of interior decoration equipment and discloses an indoor putty spraying machine with a backwashing structure. It solves the problems of easy pipe blockage, uneven putty mixing, and inconvenient backwashing operation in existing putty spraying machines. By setting up a backwashing device, the supply and discharge pipes can be quickly and effectively flushed, removing residual putty from the pipes, preventing blockage, extending the service life of the equipment, and reducing equipment maintenance time and costs. The stirring mechanism in the storage tank adopts a combined upper and lower stirring method. The blade assembly, spiral blades, and stirring auxiliary blades work together to fully stir the putty, preventing sedimentation and stratification, ensuring uniform mixing, thereby improving the putty spraying quality and making the putty spraying effect on walls and ceilings smoother and more uniform. Integrating stirring, spraying, and backwashing functions into one unit reduces the equipment's footprint and improves its practicality and versatility.

This invention relates to the field of chillers, and more particularly to a chilled water device. Technical solution: It includes an interconnected liquid storage system and a heat exchange system. The liquid storage system includes a tank with an outlet and a replenishment port. The tank is connected to the heat exchange system via a liquid inlet assembly. A filter assembly, which interfaces with the liquid inlet assembly, is installed inside the tank to filter the circulating medium flowing into the tank. Technical effect: This device reduces backwashing time and improves the cleaning effect on the filter screen, avoiding system flow and temperature fluctuations caused by traditional long-term backwashing.

This invention discloses a self-cleaning pretreatment system for a water analyzer, comprising a housing and a self-cleaning assembly. The housing contains a filter module within its filter chamber. The self-cleaning assembly includes a multi-way valve group connected to a cleaning chamber and a discharge chamber. The multi-way valve group is connected to a backwash water pump, a compressed air source module, and a dosing pump. The self-cleaning module also includes a discharge valve connected to the cleaning chamber and the discharge chamber. This invention employs pulsed gas-liquid backwashing combined with chemical cleaning, significantly improving the cleaning effect on the filter element compared to traditional methods and extending its service life. During operation, the equipment uses a PLC controller for fully automated control, eliminating the need for manual intervention. Remote monitoring and operation are possible, reducing maintenance costs. Compared to traditional methods, it saves on reagent consumption and reduces wastewater discharge.

The present application belongs to the technical field of water treatment, and specifically relates to a siphon valveless filter tank for water treatment and a backwashing method. The filter tank comprises a filter tank main body, a water inlet system, a filtering system, a backwashing system, a clean water collecting system and a control valve assembly. The inside of the filter tank is provided with, from top to bottom, a clean water area, an ultra-high space, a sand washing tank, a filter material layer, a supporting layer, an air-water distributor and a water distribution area, and a vertical shaft water distribution channel is arranged in parallel on the side. The water inlet system eliminates the air entrainment phenomenon through the vertical shaft water distribution channel. The backwashing of the filter tank comprises two modes of hydraulic automatic control and program control, and both modes integrate air-water combined backwashing operation. The present application combines the advantages of homogeneous filter material deep bed filtration and hydraulic automatic control, realizes air-water combined backwashing, and efficiently removes impurities in the filter layer. The filter tank has compact structure, is easy to operate and maintain, and can expand the treatment capacity of a single tank as needed, and is suitable for water treatment scenes such as water supply treatment, sewage treatment and water purification, and is especially suitable for new construction and old plant reconstruction of medium and small water plants.

The application relates to a double-gate-valve-based drainage anti-backflow and anti-blocking device. The double-gate-valve-based drainage anti-backflow and anti-blocking device comprises the following: a secondary pipeline is installed on a primary pipeline through a flange plate, a primary gate valve is installed on the secondary pipeline, a drain pipe is arranged on the secondary pipeline between the flange plate and the primary gate valve, the drain pipe is vertically downward, and a secondary gate valve is arranged on the drain pipe; the other end of the secondary pipeline is connected with a water pump through a hose, and the water pump is installed in a water collecting pit. The scheme provided by the application can physically isolate a backflow path through the primary gate valve arranged on the secondary pipeline, can reduce the leakage risk compared with a traditional check valve, can effectively reduce the damage of the water pump caused by the backflow of water flow in the pipeline, can drive a backwashing pipeline by using gravitational potential energy through the arrangement of the drain pipe and the secondary gate valve, can prevent the deposition of silt, can realize the anti-backflow and anti-blocking functions through the time sequence action of the double gate valves, and can empty the water flow in the main pipeline, and can reduce the starting load and starting current of the water pump.

The utility model discloses a marine water treatment ultrafiltration membrane assembly which comprises an ultrafiltration liquid outlet seat, an ultrafiltration liquid inlet seat fixedly arranged at one end in the ultrafiltration liquid outlet seat in a penetrating manner, an ultrafiltration outer sleeve fixedly arranged at one end of the ultrafiltration liquid outlet seat, and an ultrafiltration membrane rod fixedly arranged at one end of the ultrafiltration liquid inlet seat in a penetrating manner; according to the utility model, by closing the electromagnetic valves at the ultrafiltration liquid outlet flange pipe and the ultrafiltration liquid inlet flange pipe, purified water is pumped in from the back-flushing flange pipe and the front-flushing flange pipe through flushing equipment; at the moment, flushing water is pumped in through a forward flushing flange pipe, is pumped into an ultrafiltration inner liquid inlet hole and an ultrafiltration outer liquid inlet hole by a pressure pump through an inner annular groove and an outer annular groove which are connected with an ultrafiltration liquid inlet pipe, and flows out into an ultrafiltration outer sleeve for forward flushing; meanwhile, washing water is pumped into the ultrafiltration membrane rods from a cavity between the ultrafiltration liquid outlet seat and the ultrafiltration liquid inlet seat body for backwashing after being pumped through a backwashing flange pipe, so that the ultrafiltration membrane assembly can be washed more efficiently.

This invention discloses a membrane bioreactor (MBR) treatment method and a field return system for wastewater from sheep slaughterhouses. After three-stage pretreatment, the wastewater undergoes two-stage anoxic-aerobic denitrification, with segmented influent and two-stage internal recirculation. A short-range nitrification window is created in the first-stage aerobic zone with low dissolved oxygen through intermittent aeration, while stable nitrification occurs in the second-stage aerobic zone. The biochemically treated effluent enters a PVDF submerged ultrafiltration (MBR), where the mixed liquor suspended solids concentration and flux are controlled. Backwashing / relaxation and chemical cleaning sequences are triggered by the increase in transmembrane pressure difference per unit time, enhancing shock and fouling resistance. MBR permeate is fed into a field return tank and connected to the field return system. Precise water and fertilizer return and salt control are achieved through rapid nitrogen and phosphorus measurement, application decision-making, and stratified drip irrigation valve control. This scheme can achieve effluent ammonia nitrogen ≤3 mg / L, high total nitrogen removal, and reduced membrane fouling and nitrogen loss.

This invention belongs to the field of water filtration and purification technology, specifically a repair device adapted to water purifier filter cartridges. It includes a valve head with multiple telescopic modules arranged on its inner outer edge. A cleaning module is located on the side of the telescopic modules closest to the ground, and a wear self-inspection module is located on the side of the cleaning module furthest from the telescopic modules. This invention provides relatively flexible shearing force through a nylon brush plate and an inner arc silicone plate, physically peeling away oil stains adhering to the filter wall. At the macroscopic level, the spiral distribution and circumferential rotation of the nylon brush plate and the inner arc silicone plate create an overall primary spiral flow field. At the microscopic level, the jet holes arranged in a circumferential gradient on the nylon brush plate and the silicone plate generate local tangential jets, creating a double spiral flow field shearing force that effectively flushes away colloidal impurities embedded in the filter screen pores while avoiding the positive pressure effect of backwashing.

The utility model relates to a kind of automatic backflushing large-flow filter, it is equipped with backflushing mechanism for flushing filter screen, backflushing mechanism includes mounting plate, spray cavity, extraction cylinder, piston plate, extraction rod, mounting plate is fixedly connected at the back of filter screen, spray cavity is slidably connected on the inner side wall of mounting plate, multiple water outlets are opened in the end of spray cavity close to filter screen, extraction cylinder is fixedly connected on the side wall of mounting plate, fixedly communicated with water inlet pipe on the side wall of extraction cylinder, water outlet pipe is fixedly connected between extraction cylinder and spray cavity, water inlet pipe and water outlet pipe are all connected with one-way valve;Piston plate is sealingly slidably connected on the inner side wall of extraction cylinder, the utility model is realized to filter screen by the action of mounting plate and spray cavity inside shell, automatic backflushing to filter screen is realized, improve filter screen service life, avoid frequent shutdown disassembly, replace filter screen, and additional backflushing channel does not need to be set, overall structure layout is reasonable.

This utility model discloses a pipeline water supply filtration device, including a water supply pipe, a filter screen rotatably connected to the water supply pipe, a water-stop plate for sealing the water supply pipe inside the water supply pipe, and a slag outlet located between the filter screen and the water-stop plate in the water supply pipe. After the water-stop plate seals the water supply pipe, it can release the filter screen from its confinement, allowing the filter screen to rotate freely. This device is easy to operate. By rotating the filter screen and simultaneously opening the slag outlet, backwashing of the filter screen can be achieved, thereby effectively reducing filter screen clogging and cleaning up the intercepted debris in the water supply pipe. It does not require disassembling the water supply pipe, and offers excellent filtration effect and high filtration efficiency.

This application discloses a dual-fluid, dual-channel nozzle specifically designed for large roll and support roll spraying quenching machines. It mainly comprises a nozzle body, spiral guide vanes, a mixing chamber, and a diffusion nozzle. This invention features gas-liquid swirling mixing, filtration, backwashing, and self-cleaning effects. Clean water passes through the filter element and is spirally turbulent by an array of spiral turbulence vanes A, creating a central spiral flow field. The airflow, after being guided through the annular cavity between the nozzle body and the guide chamber, enters the space between the fixed sleeve and the outer wall of the cavity, where it is spirally turbulent by the spiral array of spiral turbulence vanes B, forming a uniformly distributed annular swirling field. The gas and liquid phases ultimately mix and contact inside the diffusion nozzle of the mixing chamber. The gas swirling flow, carrying tangential velocity, surrounds the water flow on its outer edge, while the water swirling flow, carrying circumferential velocity, diffuses from the center outwards, creating a collisional envelopment with the annular airflow. The velocity difference between the two swirling flows generates continuous shear force at the gas-liquid interface, constantly breaking up the water flow.

The application discloses an intelligent aquaculture wastewater treatment device and method based on water pollution treatment, and relates to the technical field of wastewater treatment.The device comprises a treatment bin, at least one water inlet, a grid, a driving part, a first filter module and a second filter module.The water inlet is in communication with the treatment bin.The grid is arranged between the water inlet and the treatment bin.The driving part is located inside the treatment bin and can stretch and retract along the height.The first filter module and the second filter module are installed in a back-to-back and superimposed manner.The first filter module and the second filter module are connected with the driving part and driven by the driving part to realize overturning.The synergistic control of the grid pre-interception, bubble-assisted separation, telescopic overturning double-layer filter module, magnetic floating self-cleaning and annular brush mechanical cleaning and backflow backwashing realizes efficient interception, online self-cleaning and water resource recycling of suspended solids and particulate pollutants in wastewater.

The utility model relates to water treatment technical field, and disclose a kind of high density land melas sedimentation tank equipment of uniform distribution, including sedimentation tank body, the water inlet pipe is fixedly installed in the side of sedimentation tank body near upper end, the rear end of water inlet pipe is installed in the inside of sedimentation tank body near, and the rear end of uniform distribution water distribution channel system is installed in the inside of sedimentation tank body near, the rear end of long water distribution channel module is installed in the inside of sedimentation tank body near uniform distribution water distribution channel system, the utility model is provided with uniform distribution water distribution channel system and lengthening formula high stability pry installation customized inclined plate module, so that in flow state aspect, water body flow state distribution is uniform, and effective sedimentation area is compared traditional multiplicate increase, and sedimentation inclined plate contact area increases, efficiency also thus increases, simultaneously by being provided with center transmission dead angle free mud scraping module and high -efficient backwashing system, sedimentation effluent water is close to zero disturbance to sedimentation mud or not easy sedimentation sludge, so that the equipment can be in sewage treatment materialization sedimentation treatment process, efficiency multiplicate promotion.

This utility model discloses a ball valve, comprising: a main valve body, a valve ball, a drain pipe, and a filter assembly. A secondary valve body is connected to one side of the main valve body. The valve ball is installed between the main valve body and the secondary valve body. A drain port is provided at the bottom of the drain pipe. The filter assembly is installed between the main valve body and the drain pipe, and includes: a first flow port, a second flow port, a filter screen, a sealing cap, a first connecting arm, and a second connecting arm. The first and second flow ports are respectively located in the main valve body and the drain pipe. The filter screen rotates between the first and second flow ports, the sealing cap rotates at the drain port, and the first and second connecting arms rotate on the filter screen and the sealing cap, respectively, and are slidably arranged between each other. This utility model, through its coherent structural design, allows for backwashing of the filter screen, thereby reducing impurities remaining on the filter screen, improving the filtration efficiency of the filter screen, and extending the service life of the ball valve.

The application discloses a kind of aquaculture wastewater treatment equipment, including filtering mechanism, water inlet mechanism, backwashing mechanism, drive mechanism and residue discharge mechanism, filtering mechanism includes processing box and the filter plate being installed in the inside of processing box;Water inlet mechanism is set at the top of processing box, for when wastewater in rearing pond is introduced into processing box during work;Backwashing mechanism is installed in the inside of processing box and is located below filter plate, for when the bottom of filter plate is washed during work;Drive mechanism is installed on the outside of processing box and is transmission connection with backwashing mechanism, for when filter plate is blocked, drive backwashing mechanism to work;Residue discharge mechanism is set in processing box, for when the residue on the top of filter plate is too much and backwashing mechanism cannot work, residue on the top of filter plate is discharged in processing box, solve the problem that staff needs to clean or replace filter plate frequently, it is more troublesome.

The utility model discloses a piezometric tube with a backwashing structure, which comprises a tube body, a washing assembly and a positioning assembly, the tube body comprises a guide tube section and a permeable section which are of an up-down structure, the washing assembly is arranged in the tube body and is provided with a water outlet tube, the positioning assembly comprises a sleeve, a positioning plate and an elastic piece, and the sleeve is connected to the water outlet tube. The sleeve is provided with a sliding way facing the inner wall of the pipe body, the positioning plate is slidably arranged on the sliding way, the elastic piece is arranged between the sleeve and the positioning plate, and the positioning plate keeps making contact with the inner wall of the pipe body under the elastic force of the elastic piece. By means of continuous elastic pressing of the elastic piece on the positioning plate, a constraint structure is formed between the water outlet pipe and the inner wall of the pipe body, the structure can effectively restrain transverse shaking caused by fluid impact in backwashing operation, vibration energy is absorbed through deformation of the elastic piece, and therefore the vibration amplitude and frequency of the washing assembly are reduced, and the washing efficiency is improved. The dynamic load impact of the joint part is obviously reduced, and the stability and durability of the whole structure are enhanced.

The application discloses a filtering system, relates to the technical field of water treatment, and can be applied to an integrated pump station.The filtering system comprises a filtering water tank, a backwashing water tank, a communication pipe, a filtering membrane group, a driving piece, a fan and a blowdown structure.The filtering water tank is connected with the backwashing water tank through the communication pipe.The filtering membrane group is composed of multiple filtering membranes which are arranged at intervals and a water collecting pipe, and the water collecting pipe is communicated with the communication pipe.The backwashing water tank adopts a structure with water inlet at the bottom and water outlet at the top, the filtering water tank is provided with the blowdown structure at the bottom, and the filtering system is integrally installed on a support.In normal filtering, raw water enters the filtering water tank, is purified by the filtering membrane group and is collected into the backwashing water tank through the water collecting pipe.When the filtering membrane is blocked and the water production decreases, the system starts backwashing: the driving piece drives clean water in the backwashing water tank to flow back to wash the filtering membrane, and after backwashing is completed, sludge is discharged, and the system restores water production.The filtering system provided by the application has the advantages of compact structure, complete backwashing, difficulty in blocking, and effective improvement of filtering efficiency and operation stability.

This application relates to the field of construction wastewater treatment technology, and in particular to a multi-layer filtration structure for construction wastewater, including a primary filtration mechanism, a fine filtration mechanism, a backwashing mechanism, and a collection tank; the primary filtration mechanism includes a filter tank, and stainless steel grids and sieve plates arranged sequentially from top to bottom on the inner wall of the filter tank; the fine filtration mechanism includes a fine filter cartridge arranged on the side of the filter tank, a limiting ring fixedly provided on the inner wall of the fine filter cartridge, and a sliding ring corresponding to the limiting ring slidably provided on the inner wall of the fine filter cartridge, and a stainless steel filter screen fixedly provided on the lower surface of the sliding ring; by setting up a primary filtration mechanism, a fine filtration mechanism, and a backwashing mechanism, this filtration structure can achieve staged filtration of construction wastewater with significantly improved efficiency, especially significantly improving the interception rate of small particles; moreover, the backwashing system effectively extends the service life of the filter cartridge; and the overall energy consumption is greatly reduced, and it supports long-term uninterrupted operation.

This application discloses a deep denitrification system for ultra-low C / N ratio kitchen waste slurry, belonging to the field of kitchen wastewater treatment technology. The system comprises three sequentially connected stages: pretreatment, fine treatment, and deep treatment. The pretreatment stage involves pretreatment, hydrolysis, acidification, and centrifugation, followed by pumping into an anaerobic external circulation membrane bioreactor composed of an anaerobic fermenter and an external PVDF tubular membrane. The PVDF tubular membrane effluent is divided into three streams: one is returned to the anaerobic fermenter, the other directly enters the flotation unit, or the third enters a combined deep denitrification coupling device consisting of an anaerobic reactor-membrane aeration biofilm reactor-anaerobic ammonia oxidation reactor. After deep denitrification, the effluent flows into the flotation unit, and after two-stage nitrification, it enters the ultrafiltration system. Part of the ultrafiltration permeate is reused for backwashing, and the concentrate is returned to the deep denitrification coupling device to adjust the C / N ratio. This application achieves differentiated efficiency enhancement, resource reuse, and energy saving of ultra-low C / N ratio kitchen waste slurry through three-stage gradient synergy and precise seasonal control, enabling deep denitrification without the need for an external carbon source.