77results about How to "Improve air flotation effect" patented technology

The invention discloses an air floatation device and belongs to the field of water treating equipment. The air floatation device comprises a micro nanometer bubble generation device, a micro nanometer bubble generator, an air control valve and an air floatation tank, wherein a water inlet tube, an air inlet tube and a water outlet tube are arranged on the micro nanometer bubble generation device, the water inlet tube is used for leading in water, the air control valve is connected onto the air inlet tube, an opening for being connected with an air source is arranged on the air control valve, and the water outlet tube is connected with the micro nanometer bubble generator. A water inlet is arranged on the micro nanometer bubble generator which is arranged in the air floatation tank. The air floatation device is a forcing dissolved gas air floatation device, uses the micro nanometer bubble generator to produce small bubble water and improves air dissolution efficiency. Simultaneously produced small bubbles have negative charge, have good adsorption effect on greasy dirt and particles and greatly improve air floatation effect. The whole device does not need to increase extra operating cost, and the air floatation device is a revolutionary improvement compared with a traditional air floatation method.

The invention discloses a totally-dissolved deep-layer air flotation combined device and a sewage treatment method thereof, relating to the technical field of environmental protection and aiming at solving the technical problem of unstable air floatation effect of various air floatation processes so as to further effectively improve the air floatation effect. The combined device comprises a sewage tank, a drug feeding groove, a lifting pump, a totally-dissolved air floatation pot and an air floatation tank, wherein the air floatation tank with the depth of 6 to 9m, is divided into a releasing zone and a separating zone. The upper layer of the releasing zone is connected with a mud layer of the separating zone, the middle layer is a padding layer, and a releaser arranged at the lower layer is connected (communicated) with the lower part of the totally-dissolved air floatation pot by a pipeline; the upper part of the separating zone is the mud layer for discharging floating residues, a water discharging pipe arranged at the middle part is used for discharging treated water out of the air floatation tank, and a mud bucket zone arranged at the lower part is used for discharging sinking mud residues. The invention has the characteristics of stable air floatation, good effect, high COD, color and SS removing rate, good transparency of outgoing water and less drug feeding quantity.

The invention provides an inclined tube floating device for waste water treatment, belonging to the technical field of environmental protection, which is characterized in that: a water inlet is communicated with a whirl mixer arranged at the front end of the device; a mud bucket is arranged on the bottom end of the device body; the device is internally provided with a perforated dredge pipe above which is mounted with a depression area; the depression area is internally provided with an inclined plate and communicated with an absorption area which is arranged at the back end of a buffer area, the absorption area is internally provided with a releasing device of air flotation microbubbles, namely, an activated ploy-oxygen aerator; a mud collecting tank is also mounted on the top end of the absorption area; a catchment area is mounted on the top end of the buffer area, and water collecting equipment is mounted in the catchment area; the upper part of a reaction area is provided with an electric scraping vehicle for removing scum generated by air flotation, and the tail part thereof is provided with an effluent tank which is internally provided with a liquid level regulator; the bottom of the liquid level regulator is provided with a drain pipe. The invention has the beneficial effects of improving treatment effect, evenly mixing medicament and waste water, saving occupied area and materials consumption, increasing air flotation effect, lowering dramatically moisture content of the scum, eliminating dead zones in sludge discharging of devices, optimizing the effluent water quality and reducing moisture content of the sludge.

The invention discloses a water purification system and a water purification method for an inclined tube floating sedimentation tank. The bottom of a flocculating chamber is communicated with the bottom of an air flotation contact chamber, the bottom of the air flotation contact chamber is provided with a water inlet of a sedimentation water distribution area, a gate plate is arranged at the water inlet, an inclined tube sedimentation area is positioned above the sedimentation water distribution area, an air flotation separation chamber is positioned above the inclined tube sedimentation area, and the inclined tube sedimentation area is communicated with the sedimentation water distribution area and the air flotation separation chamber. The water purification method comprises the following steps of: (1) adjusting the state of each tube orifice of the water purification system; (2) mixing raw water and a coagulant; (3) performing flocculation; (4) performing air flotation contact; and (5) performing air flotation separation and sedimentation to obtain purified water. When an air flotation and sedimentation combined process and a single sedimentation process are operated, the converting operation of the two processes is simple. By selecting different operating units for water of a yellow water introduction reservoir according to the water quality, the water temperature and the water quantity changed with season and climate, the effect of double results with half work can be achieved.

A process for cleaning the used bath water includes filter, flocculating, air floating, solid-liquid separation, adsorption and filtering again. Its advantage is high cleaning effect.

The invention discloses a micro-nano air floatation tank which comprises an air floatation head (1), a partition wall (2), a scum tank (3), a water inlet (4), a water outlet (5), a scum scraping machine (6) and a micro-nano bubble generator (7), wherein a cavity structure is arranged in a main body; the scum scraping machine (6) arranged at the top opening of the main body can remove scum produced on the water surface of a reactor in the fluidization air floatation process; the interior of an air floatation tank body is divided into a contact chamber (8) and a separation chamber (9) by the partition wall (2) to fulfill the full contact, adhesion and floatation of micro-bubbles and impurities in water. The micro-nano air floatation tank is low in failure rate, easy to maintain and good in scraping and air floatation effect, and has the outstanding advantages of low manufacturing cost and operation cost and the like.

The invention discloses a method for treating acidic dye printing and dyeing wastewater, which belongs to the field of wastewater treatment. The method comprises the steps of (1) filtering collected acidic printing and dyeing wastewater through a screen, then enabling the acidic printing and dyeing wastewater to enter a regulation tank, and using alkali waste to regulate the pH value of the acidic printing and dyeing wastewater to be 6.0-8.0; (2) feeding anionic surfactants into the regulation tank, and performing aeration decoloring treatment through a micro-nano aeration device; (3) enabling wastewater after aeration decoloring treatment to flowing through a sepiolite device of immobilized catalysts from bottom to top, wherein chemical oxygen demand (COD) in processed outlet water is lower than 100mg / L, the chromaticity is lower than 40mg / L, and the COD and the chromaticity both reach level 1 emission standards in Discharge standard of water pollutant for dyeing and finishing of textile industry. By means of combination of the anionic surfactants and the micro-nano aeration device, the method performs the aeration decoloring treatment on the acidic dye printing and dyeing wastewater, and absorption-catalysis is performed through the sepiolite device of the immobilized catalysts to further reduce the COD content in the wastewater. The method has the advantages of being simple in process flow, small in floor area, remarkable in effect of treatment on the COD and the chromaticity in the acidic dye printing and dyeing wastewater, and the like.

The invention discloses floatation equipment which relates to the field of mechanical equipment and comprises a barrel, a mud bucket and a gas dissolving device, wherein the barrel is provided with a water inlet and a water outlet, the mud bucket is arranged at the bottom of the barrel and is provided with a mud discharge hole, a drossing device and a slag hole are arranged on the top of the barrel, an inclined plate section is arranged in the barrel and is arranged between the water inlet and the water outlet, a micro-nano bubble generator is arranged between the inclined plate section and the water outlet and is connected with the gas dissolving device, and a micro-nano bubble generating device is arranged in the gas dissolving device. Due to the dual actions of an inclined plate and the gas dissolving device, large-particle flocculating constituents settle to form sludge, and small-particle flocculating constituents float on the water surface; clear water after dual solid-liquid separation is high in recycling standard; since the micro-nano bubble generator is utilized, not only is the gas dissolving efficiency improved, but also the adsorption effect can be realized on grease dirt and other substances, and the floatation effect is greatly improved.

The invention belongs to a pressure reduction release eddy flow air floatation tank. An air dissolution water inlet, a waste water inlet, a scum discharge port, an exhaust port, a water outlet and a backflow port are formed in a tank body. A center pipe is arranged inside the tank body and is perpendicular to the tank bottom, a supporting plate is arranged at the bottom of the center pipe, a partition plate is arranged on the center pipe, blades are arranged on the upper portion of the partition plate, and small holes are formed in the pipe wall between the lower portion of the portion plate and an air dissolution water inlet pipe. A water outlet pipe is arranged on one side inside the thank and connected with the water outlet. A scum tank is arranged on the upper portion of the other side inside the tank and communicated with the scum discharge port. An exhaust pipe is arranged in the center of a tank body end socket. A unique structure is adopted for the air floatation tank, and all functional zones are independent in position and are closely combined in treatment function, so that waste water and agents are mixed more fully under hydraulic power, and the utilization rate of the agents is increased. Under the action of an eddy flow field, the scum-water separation process is intensified, and the scum separation efficiency is improved. The air floatation tank is simple in structure, the size of the air floatation tank can reduced, and the air floatation effect can be improved.

The invention belongs to the field of environmental engineering wastewater purification, and specifically relates to a coating wastewater treatment system and method. The coating wastewater treatmentsystem comprises an adjusting tank, a coagulation reaction sedimentation tank, a flocculation air flotation device, a neutral reaction tank, a water collecting tank, a hydroxyl solution generating system, a filtration adsorber and a clear water recycling tank which are connected with one another; a first dosing device is used for dosing for the coagulation reaction sedimentation tank, and a seconddosing device is used for dosing for the flocculation air flotation device. According to the coating wastewater treatment method provided by the invention, coating wastewater enters into the adjusting tank, the coagulation reaction sedimentation tank, the flocculation air flotation device, the neutral reaction tank, the water collecting tank, the hydroxyl solution generating system, the filtration adsorber and the clear water recycling tank in sequence to complete primary treatment process and deep treatment process on wastewater. The coating wastewater integral treatment equipment designed in the invention is thorough in treatment, free of secondary pollution and short in period, and the effluent quality meets wastewater recycling and up-to-standard discharge standards, so that the equipment is expected to be used for industrial treatment of coating wastewater.

The invention relates to a method for removing algae by applying micro-bubble air flotation of a multiphase flow pump. The method comprises the following step of releasing air dissolved water below a water body containing an algal layer, wherein the air dissolved water is formed in such a way that air and natural water simultaneously enter the multiphase flow pump under the action of negative pressure, dispersed air is cut many times by using a multistage impeller rotating at high speed in the multiphase flow pump, the air is instantly dissolved into the natural water in a highly dispersed state in a high pressure environment in the multiphase flow pump and rapidly saturated, and then is stabilized and contacted by an air dissolved tank for 50seconds-1hour, and the air dissolved water contains a great number of micro air bubbles with the diameter of small than 30mum, and the air dissolved water is released by decompressing to a position 0.3-1.2m away from the downside of the water body containing the algal layer. The method has the advantages of ideal air flotation effect achieved without adding a coagulant, no secondary pollution, no limitation of minimum water treatment quantity, simple process equipment, low device energy consumption and high system operation stability.

The invention discloses a disposing device of oil field waste water especially heavy crude waste water with cryogenic plasma technology, which comprises the following steps: compositing air feeder thread valve 1, inlet pipe thread valve 2, dissolved pump 3 and stabilized voltage pot 4 as dissolved system; compositing container 6, distributor 7, scum system 8, slag outlet 9 and water outlet 10 as multiple function reactor 5; setting discharged electrode system 11 in the reactor 5; connecting upper end of electrode with impulsing power source 12.This device possesses functions of air-float, highly effective sterilization and advanced oxidation, which can realize higher effective sterilization and polymerization and matter spice degradation.

The invention discloses an efficient oil-containing sewage electric flocculation purification device which comprises a water storage tank, an electric flocculation area and a purification area, wherein a water flow inlet and a water flow outlet are formed in the water storage tank; the water flow outlet is connected with the electric flocculation area through a first water outlet tube; a pluralityof cylindrical multi-loop electric flocculation devices are arranged inside the electric flocculation area; water outlets of the cylindrical multi-loop electric flocculation devices are connected with the purification area through second water outlet tubes; a compulsive air floating area, an inclined plate sedimentation area and a foam capturing area are arranged inside the purification area; aninclined plate sedimentation device is arranged inside the inclined plate sedimentation area; the compulsive air floating area is positioned below the inclined plate sedimentation area; a pressurizingair floating device is arranged inside the compulsive air floating area; the foam capturing area is positioned above the inclined plate sedimentation area; a foam capturing device is arranged insidethe foam capturing area. The device is good in separation effect, high in integration degree and relatively simple and convenient in mounting management, and the overall height of the device can be lowered while an electric flocculation effect is ensured.

The invention discloses a preparation method of cellophane and belongs to the field of cellophane. Sodium oleate is taken as a main material, a biopolymer anionic surfactant, which is a polymer fattyacid trapping agent, is synthesized through aqueous solution free radical polymerization and is mainly used for electrostatic adsorption of printing ink particles containing anion groups and anions inthe polymer in bivalent calcium ions, formed calcium bridges can gather printing ink particles and remove the particles through flotation to play the role in trapping the printing ink particles, theprinting ink removal rate is high, meanwhile, the agent has the capacity of emulsification, permeability, high fouling removal performance and low surface tension and can remove a large amount of waste paper printing ink, and the utilization rate of recycled paper is improved. The defects that existing cellophane can be torn easily and softened after absorbing water are overcome, and the problemsthat the cellophane consumes a large quantity of waste paper, a large amount of printing ink in the paper is difficult to remove, and most of existing cellophane has the problems of poorer damp-proof,water-proof and mold-proof performance are solved.

The invention provides a method using a coagulation air floatation machine to treat sewage. The method includes: the filtered and flocculently precipitated sewage is guided into the coagulation air floatation machine, and coagulant is added; the motor of the coagulation air floatation machine drives blades to rotate through a rotary shaft so as to allow the coagulant to have mixed reaction with the impurities in the sewage to form floc; an ultrasonic transmitter cavitates air entering the coagulation air floatation machine through an air inlet pipe to generate fine bubbles; the fine bubbles floats and adheres and carries away the floc during floatation; the floc floats to the water surface along with the fine bubbles and forms floating residues, the floating residues are removed, and the water treated by the fine bubbles is discharged from the water outlet in the bottom of the coagulation air floatation machine. The method has the advantages that the water treatment method is simple, low in cost and capable of effectively removing the impurities such as suspended particles, emulsified oil, fibers and heavy metal in the sewage, environmentally friendly, free of pollution and high in market application value.

The invention provides a radial-flow air-flotation thickening apparatus for sludge. The apparatus comprises a contact area 1, a separation zone 2, a water outlet channel 3, a scum tank 4, a sludge tank 5, an air-dissolved water inlet pipe 6, a sludge inlet pipe 7, an effluent collecting pipe 8, a water outlet pipe 9, a slag discharge pipe 10, a sludge discharge pipe 11, a sludge and slag scraping machine 12 and a micro-nano bubble releaser 13, wherein the bottom of the sludge and slag scraping machine 12 is equipped with a sludge scraping plate 15 which is used for scraping sludge deposited at the bottom of a pool into the sludge tank 5, a slag scraping plate 14 is installed on a water surface and used for scraping thickened sludge into the scum tank 4, the micro-nano bubble releaser 13 introduces air-dissolved water into the bottom of the contact area 1, the effluent collecting pipe 8 introduces clear water at the bottom of the separation zone into the water outlet channel 3, the contact area 1 is located at the center of the separation zone 2, the water outlet channel 3 is located at the inner side of the separation zone 2, the scum tank 4 is hung on the sidewall of the water outlet channel 3, and the sludge tank 5 is located at the bottom of the separation zone 2. The apparatus has the advantages of a simple structure, easy maintenance, low cost, an ideal sludge thickening effect and applicability to large-scale sewage treatment plants.

The invention discloses a sludge oil removal system. The sludge oil removal system comprises a stirring device, a reaction device, a middle water tank and a dissolved gas tank, wherein a sludge inlet is formed in the top of the stirring device, and a sludge discharging opening is formed in the bottom of the stirring device; the lower part of the stirring device is communicated with the bottom of the reaction device by virtue of a first communication pipe, the reaction device is communicated with the top of the middle water tank, the bottom of the middle water tank is communicated with the top of the dissolved gas tank, the bottom of the dissolved gas tank is communicated with a gas floatation releaser which is arranged on the inner bottom of the reaction device, and the gas floatation releaser is arranged below a sludge outlet of the communication pipe; an oil discharging opening is formed in the top of the reaction device, and a sludge discharging opening is formed in the bottom of the reaction device. The invention also discloses a sludge oil removal method. Oil is removed by virtue of dissolved gas floatation, partial sludge in the reaction device enters the stirring device so as to further remove the oil, the oil content in the sludge is further reduced, and the oil removal effect is greatly improved; meanwhile, the utilization rate of a charged chemical reagent is increased; partial gas floatation water backflows to the middle water tank to be recycled, so that the water consumption is greatly reduced.

The invention relates to a mechanical stirring type co-coagulation flotation coupled two-layer horizontal sedimentation tank water purifying system and a method thereof. Dissolved air flotation is organically combined with a two-layer horizontal sedimentation tank to form a novel floatation and sedimentation tank. Mechanical flocculation and the dissolved air floatation are organically combined through a co-coagulation flotation technology to form co-coagulation dissolved air floatation in order to enhance the stability of a bubble floc. The air floatation are organically combined with ozone oxidation to realize full contact with polluting substances in water in order to greatly enhance the ozone oxidation effect. Mechanical flocculation, co-coagulation flotation and two-layer horizontal sedimentation are organically combined, so the operation is convenient, and the stable bubble floc is formed while effectively controlling the rotating speed and reducing the water conservancy loss. The method has the advantages of flexible running manner, effective reduction of the running cost, high water quality change adaptability, simple structure, high efficiency, convenience in running, and wide application prospect.

The invention discloses an environment-friendly dissolved-gas gas floatation machine for treating sewage by mixing oxygen and ozone. The environment-friendly dissolved-gas gas floatation machine for treating sewage by mixing oxygen and ozone comprises a baffling water inlet area, a gas floatation machine main body, a mixed reaction area and a gas floatation area; the baffling water inlet area is arranged at one end, near a third water pump, of the internal part of the gas floatation machine main body; the mixed reaction area is arranged on one side of the baffling water inlet area and in the gas floatation area; the gas floatation area is arranged on one side of the mixed reaction and in the gas floatation machine main body; a transmission caterpillar track is arranged at the top end in the gas floatation area; slag scraping plates are arranged on the surface of the transmission caterpillar track uniformly; a slag discharge port is formed in the middle position of one side, far away from the mixed reaction area, of the gas floatation area; and a sludge collecting groove is fixed in the outer wall of the gas floatation area and below the slag discharge port. A dissolved gas tank is arranged, mixed gas of oxygen and ozone is introduced into the dissolved gas tank, and the gas dissolution effect of the mixed gas of oxygen and ozone is better than that of the air, so that the gas floatation effect is better.

The invention discloses an air foot. The air foot comprises an air foot body, the air foot body is in a rectangular plate shape, and chamfered faces are arranged at the four corners of a rectangular plate; a first annular air leakage groove and a second annular air leakage groove are formed at the bottom face of the air foot body, the first annular air leakage groove and the second annular air leakage groove are coaxially formed and are spaced inwards in the radial direction relative to the second annular air leakage groove, and an air floating area is formed between the first annular air leakage groove and the second annular air leakage groove; the bottom surface of the rectangular air foot body is further provided with a vacuum preloading area located in the second annular air leakage groove; each side face and / or each chamfered face of the air foot body are / is provided with an air leakage port; a plurality of air leakage channels communicated with the first annular air leakage groove and the second annular air leakage groove are formed in the air foot body; the plurality of air leakage channels are respectively communicated with the air leakage ports; and compared with the priorart, the air foot is stable in performance, simple in structure, convenient to install and use and low in machining cost.

The invention relates to an outgassing demulsification device of an ultrasonic air floatation system. An ultrasonic reaction region is arranged on one side of the inner of a demulsification pool, a separating region is arranged on the other side of the inner of the demulsification pool, and a water inlet is installed on the demulsification pool which is arranged on the lower portion of the ultrasonic reaction region. The device is characterized in that the outgassing demulsification device is arranged in the ultrasonic reaction region, and the outgassing demulsification device is installed on an ultrasonic generator outside the demulsification pool through a wire. The device is simple in structure, scientific in design, good in air floatation effect and good in controllability. The outgassing and the demulsification can be completed at the same time, the contact area of a transduction plate is large, bubble amounts of the device are more than those generated through a normal ultrasonic method obviously, and the device can be applied to fields such as petro, chemical industry, mechanical production, smelting and power generation widely and is suitable to treatment of high-concentration emulsified liquid.

The invention discloses an overall process method of a Fenton-like air-flotation process. The whole process method is divided into two sections: in a first stage: a main Fenton-like reaction is completed, organic pollutants in wastewater are oxidatively decomposed, a novel pure fluid static pipeline reactor is disposed in a water absorbing well or a water collecting well, a Fenton-like medicamentand a liquid caustic soda are added in the pipeline reactor, the Fenton-like medicament is thoroughly mixed and then the organic pollutants in the printing and dyeing wastewater are oxidatively decomposed, and the pH is adjusted by the liquid caustic soda; and in a second stage: completion of mud-water separation: the mixed liquid after the Fenton-like reaction enters an air flotation machine through a lift pump, the mud-water separation is completed with the aid of an air flotation auxiliary agent. The purpose of adding the PAM (Polyacrylamide) is to enable small particles in the mixed liquidto form floccules with larger particles through flocculation, and the thorough mud-water separation is facilitated. The process method not only absorbs the technical advantages of the traditional Fenton process and the air floatation process, but also solves the technical problems existing in the two conventional processes.

The invention discloses a nano-floating-island water remediation system device. The nano-floating-island water remediation system device comprises a water collecting tank, a regulation pool, an anaerobic tank, an anoxic tank, an aerobic pool and a micro- / nano-aeration biological tank which are sequentially connected, wherein a micro- / nano-aeration device, a micro- / nano-bubble generator and a plurality of solidified microbial columns are arranged in the micro- / nano-aeration biological tank, the micro- / nano-bubble generator is connected with the micro- / nano-aeration device, the solidified microbial columns are fixed on a fixed body, and a plurality of floating bodies are arranged on the fixed body. The nano-floating-island water remediation system device disclosed by the invention has the advantages that the structure is compact, the energy consumption is low, and microbes are supplemented conveniently.

The invention discloses a sedimentation air floatation composite tank which solves the problem that the land occupation area of a sedimentation tank and an air floatation tank is large at the presentstage. Main points of the technical scheme are that the sedimentation air floatation composite tank includes a sedimentation groove, a guide groove which is disposed along the top edge of the sedimentation groove and does not communicate with the sedimentation groove, and an air floatation groove which is located at one side of the sedimentation groove and communicates with the guide groove at theupper end, wherein the bottom surface of the guide groove is a guiding inclined plane which is inclined downward in a direction of the air floatation groove; the sedimentation groove is further provided with a water inlet pipe for introducing sewage into the sedimentation groove, and a discharge pipe for discharging pollutants at the bottom of the sedimentation groove; the air floatation groove is further provided with a first aeration device for increasing the bubble content of the sewage in the air floatation groove; and one side of the air floatation groove is provided with a dirt discharge groove, the top of the air floatation groove is provided with a sediment scraper that sweeps the pollutants on the water surface of the air floatation groove into the dirt discharge groove, and theair floatation groove is also provided with a water outlet pipe. The sedimentation air floatation composite tank is small in land occupied area, and can perform a purification process of sedimentationand air floatation on the sewage.

The invention provides an ultrasonic air dissolving system which has a simple structure, can guarantee gas-liquid full contact and has relatively good air flotation effect; the ultrasonic air dissolving system includes an air dissolving tank; an air dissolving tank body is a vertical column type structure; the lower side wall body of one end of the air dissolving tank is provided with a water outlet; the wall body, located at the same side of the water outlet, of the upper end of the air dissolving tank is provided with a liquid level floating ball switch; the upper side wall body of the other end of the air dissolving tank is provided with an air inlet; the top end of the air dissolving tank is provided with a water inlet; a spray nozzle with a downward opening is arranged below the water inlet and is located in the air dissolving tank; the middle of the interior of the air dissolving tank is filled with a filler; a floater of the liquid level floating ball switch is located above the filler in the air dissolving tank; the bottom of the interior of the air dissolving tank is provided with an ultrasonic generator; baffle blocks are arranged on the inner side wall of the air dissolving tank at interval.

The invention relates to a multi-stage thermal washing and screening method and system for oily sludge-containing impurities. According to the method, the oily sludge-containing impurities are screened, and screened undersize materials and oversize materials are subjected to different oil removal treatments. The system comprises a feeding subsystem, a thermal washing and screening subsystem, a centrifugal separation subsystem and an auxiliary subsystem which are connected according to working procedures; the feeding subsystem comprises an impurity screening device; the thermal washing and screening subsystem comprises small-particle material thermal washing equipment and multi-stage screening equipment which are connected in sequence; the centrifugal separation subsystem comprises solid-liquid separation equipment and oil-liquid-solid three-phase separation equipment, and a liquid-phase outlet of the solid-liquid separation equipment is connected with a feeding hole of the oil-liquid-solid three-phase separation equipment; and the auxiliary subsystem comprises large-particle material thermal washing equipment. According to the multi-stage thermal washing and screening method and system, the materials with different sizes in the oily sludge-containing impurities can be screened and classified according to sizes, different oil removal treatments can be respectively carried out, the materials with large surface areas can be cleaned more, the materials with different sizes can be respectively cleaned, the oil content of the discharged materials is ensured to be less than 2%, and sump oil recovery and water cyclic utilization are realized.

In order to solve the technical problem that in the prior art, an air dissolving device for air flotation is low in air dissolving efficiency, the invention provides an air dissolving system, an air dissolving method, a sewage treatment system and an air dissolving system. The air dissolving system comprises a sealed tank body, a water outlet is formed in the tank body, and at least two air dissolving areas including an air dissolving water area and a specific surface area increasing area are arranged in the tank body; the specific surface area increasing area is arranged above the air dissolving water area, the sewage treatment system comprises an air flotation device, a filtering system and the air dissolving system, an air flotation releaser is arranged between a water outlet of the air dissolving system and a water inlet of the air flotation device, According to the air dissolving method, after the specific surface area of water is increased, the water meets high-pressure gas to form gas dissolving water, then gas is dissolved again through an aerator, and by means of the gas dissolving system, the gas dissolving method and the sewage treatment system, more gas can be dissolved, and thin bubbles are formed. The dissolving efficiency is high, the gas utilization rate is large, bubbles are tiny, and the air flotation effect is good.

The invention discloses a novel water distribution device applicable to an air floatation tank. A plurality of U-shaped plates are distributed in the air floatation tank in parallel; two sides of theU-shaped plates are fixedly connected with inner walls at two sides of the air floatation tank respectively; a flow channel cavity is formed between the two adjacent U-shaped plates; a water inlet isformed in the air floatation tank; the water inlet is connected with one end of a water inlet pipe located in the air floatation tank; the water inlet pipe is horizontally distributed in the air floatation tank; a plurality of holes are formed in a pipe wall of the water inlet pipe; a plurality of water outlet holes are formed in a tank wall of the air floatation tank; each water outlet hole corresponds to one water discharging cavity; each water outlet hole is communicated with a side end of the corresponding water discharging cavity. The plurality of U-shaped plates are distributed in the air floatation tank in parallel and are fixed at two sides of a tank body; a certain gap is kept between the U-shaped plates; a flow direction of water flow is guided and a forward movement path of thewater flow is prolonged, so that the action time of air floatation is prolonged, the air floatation effect is effectively improved and the water quality of air floatation output water is improved. Thewater distribution device has the advantages of simple structure, simplicity and convenience for installation, relatively low cost and remarkable effect.

The invention discloses an oxidation-type air-flotation coupling ultrafiltration water purification system. The oxidation-type air-flotation coupling ultrafiltration water purification system comprises an improved CCDAF technology air-flotation pond integrating same-direction flow and different-direction flow, the improved CCDAF technology air-flotation pond is internally provided with a reverse flow collision contact chamber, a same-direction flow adhesion contact chamber, an air-flotation separation chamber and an ultrasonic chamber in sequence in the water flow direction, an immersed ultrafiltration membrane pond is connected to the improved CCDAF technology air-flotation pond, and a clear water pond is connected to the immersed ultrafiltration membrane pond; two air dissolving systemsare connected to the clear water pond and connected with the improved CCDAF technology air-flotation pond and the immersed ultrafiltration membrane pond to provide high-pressure air-dissolving water for the improved CCDAF technology air-flotation pond and the immersed ultrafiltration membrane pond. The oxidation-type air-flotation coupling ultrafiltration water purification system achieves combined use of air flotation and ultrafiltration membranes, each other's advantages can be complemented, thus particulate matter with a wider diameter range is removed, and the purpose of advanced treatmentof raw water is achieved.

The invention discloses a net stretching device. The net stretching device comprises a bearing frame and a plurality of air floating assemblies, wherein the bearing frame has an installation surface;and the plurality of air floating assemblies are arranged on a mounting surface. Each air floating assembly comprises an air floating base fixed on the mounting surface, a bearing disc, an air hole and a limiting component, wherein the bearing disc is arranged on one side, deviating from the mounting surface, of the air floatation base, the bearing disc is provided with a first surface facing theair floatation base and a second surface arranged opposite to the first surface, and the second surface can bear a mask plate frame; the air hole is formed in the air floating base and faces the firstsurface of the bearing disc so that the bearing disc floats during air blowing; and the limiting component is connected between the air floatation base and the bearing disc, and the limiting component can limit a displaceable amount of the bearing disc in a direction parallel to the mounting surface. According to the net stretching device provided by the embodiment of the invention, air floatingsupport of the air floating assembly on the mask plate frame is more stable and reliable, and an air floating effect on the mask plate frame is improved.