88results about How to "High cut-off" patented technology

The invention relates to a method for in-situ polymerization and modification of a polyvinylidene fluoride microporous membrane. In the method, polyvinylidene fluoride microporous is dissolved in triethyl phosphate at first to prepare membrane-forming precursor solution, active solution is added into the membrane-forming precursor solution for in-situ polymerization under nitrogen protection, the mixture is kept static for 18-36 hours at the reaction temperature after reaction, membrane casting solution is prepared via deaeration and is processed by a membrane forming machine to prepare a primary membrane, the primary membrane is soaked in a coagulating bath for 0-3 hour(s) and is then transferred into an deionized water bath to be immersed for 1-48 hour(s) so as to be cured into a membrane, the membrane is naturally dried in the air at the room temperature, and thus the dry hydrophilic polyvinylidene fluoride membrane is prepared. The method is environmentally friendly, the reaction conditions are mild, the preparation method is simple, modification and preparation are completed simultaneously, the repeatability is good, the method cannot be limited by the type of the microporous membrane, a high-flux separating membrane can be obtained with no needs for external pore-forming agents, and the prepared microporous membrane is a dry hydrophilic membrane.

The invention relates to the field of membrane technology, in particular to a high-temperature-resistant precision molecular weight cut-off ultrafiltration membrane and a preparation method thereof. The composition of raw materials and the definition of parameters in the preparation process of the base film ensure that the performance of the prepared wet base film is stable after the subsequent modification treatment, and can effectively improve its high temperature resistance; at the same time, combined with the modification process The definition of time, temperature and treatment method in the process makes the rejection rate of the ultrafiltration membrane to the molecular weight range of 2000-4000 reach more than 90%, which effectively improves the interception of the ultrafiltration membrane to low molecular weight substances and improves the quality of the filtration product .

The invention relates to a novel Janus polymer hollow fiber membrane and a preparation method and application thereof. Hole structures are formed in the outer surface and the inner surface of the Janus polymer hollow fiber membrane respectively, the outer surface has hydrophilic performance, the inner surface has hydrophobic performance, and the water contact angle of the outer surface is smallerthan 70 degrees. The novel Janus polymer hollow fiber membrane is prepared through the steps that 1, the two ends of the polymer hollow fiber membrane are blocked, and a blocked fiber membrane is obtained; 2, the blocked fiber membrane is immersed into an initiator solution; 3, the blocked fiber membrane supported with an initiator obtained in the step 2 is placed in a modifying solution for a reaction; 4, the modified membrane obtained in the step 3 is washed. The Janus membrane is high in flux, high in rejection and resistant to pollution, and the preparation technology is simple, easy to operate, mild in condition and high in universality.

The invention discloses a method for preparing braided tube / polymer composite hollow fibrous membrane by a thermal induced method. The method comprises the following steps of: preparing membrane-casting liquid 1 and membrane-casting liquid 2; dipping a polyethylene glycol terephthalate (PET) braided tube in a boiling NaOH solution with certain concentration to remove oil stains remained on the braided tube; modifying the braided tube of a supporting layer with a modifier; coating the high-molecular polymer membrane-casting liquid 1 onto the filament surface of the braided tube by a one-time dipping and one-time rolling method, thermoforming the round tube, and curing the tube in a gel bath; uniformly coating the membrane-casting liquid 2 on the outer surface of the membrane-laminated fibrous braided tube with spinning equipment, and curing composite filaments in cooling liquid; and displacing a diluent from a formed membrane with an extracting agent, and rinsing the membrane filamentsto obtain the braided tube / polymer composite hollow fibrous membrane. The braided tube / polymer composite hollow fibrous membrane prepared by the method has the characteristics of high flux, strength and interception and high-pressure backwash resistance; and moreover, the supporting layer and the coating layer are difficult to separate.

The invention discloses a high-throughput polyamide nanofiltration composite membrane and a preparation method thereof, which belong to the field of polymeric membrane materials. The composite membrane is prepared by the interfacial polymerization reaction between 5-(N-sulfonamido)isophthaloyl dichloride or a mixture of 5-(N-sulfonamido)isophthaloyl dichloride and 1,3,5-trimesoyl chloride and piperazine monomer, and can be widely used in a water softening process for removing bivalent cations such as Ca<2+> and Mg<2+>. The high-throughput polyamide nanofiltration composite membrane is structurally provided with an ultrathin (10nm) release layer, surface charge are low in electronegativity, the membrane surface property is smooth and hydrophilic, high throughput is shown in terms of properties, the high-throughput polyamide nanofiltration composite membrane has an excellent trapping effect on bivalent and polyvalent cations and good pollution resistance, and the high-throughput polyamide nanofiltration composite membrane can be widely applied in high-throughput domestic water purifiers, sea water desalination, brackish water pretreatment, removal of COD (chemical oxygen demand) suchas dye molecules and phenol molecules in wastewater, separation of dye / salt and material separation and concentration processes in pharmaceutical and food industries.

The invention provides a method for preparing a nanofiltration membrane with high desalination selectivity and high flux. The method comprises the following steps: S10, preparation of an aqueous phase solution and an organic phase solution, wherein the aqueous phase solution containing multifunctional polyamines, reactive hydroxyl polymer and hydrophilic polymer salt, and the organic phase solution of polyfunctional acyl chloride with at least two reactive acyl halide groups are prepared; S20, interfacial polymerization reaction, wherein an ultrafiltration diaphragm is fixed on a glass plate, then the aqueous phase solution is poured onto the surface of the ultrafiltration diaphragm, and is poured away after placed for 10-30s, the organic phase solution is poured onto the surface of the ultrafiltration diaphragm after the aqueous phase solution on the surface of the diaphragm is dry, and poured away after placed for 10-30s, the ultrafiltration diaphragm is then placed in an oven at a temperature of 40-120 DEG C for thermal treatment, and a finished product is obtained. The method for preparing the nanofiltration membrane has the advantages that while the water flux of the nanofiltration membrane is improved, the desalination selectivity of the nanofiltration membrane is expanded to a relatively large extent.

This is a kind of riverbed and seabed bedload withholding, silt promoting and anti-scouring device belonging to the water conservancy technologic field. The present invention includes: floating shade, floating body, sand permeating window and anchoring member. The floating body is equipped at the upper of the floating shade, the sand permeating window is equipped at the bottom of the floating shade, and the anchoring member is equipped at the lower part of the floating shade. The water preventing effect of the present invention is small, not flood detention, won't minify the moving motivity of silt, and won't change the original flowing direction. Therefore it will become a kind of effective silt promoting device with good flood preventing effect, little change of sideway flowing field, and without obvious partial scour.

The invention discloses an energy-saving nanofiltration membrane for a water purification system and a preparation method of the energy-saving nanofiltration membrane. The energy-saving nanofiltration membrane is composed of non-woven cloth, a polysulfone supporting layer, a loose polyamide separating layer and a dense positive charge thin layer. By properly hydrolyzing the dense nanofiltration membrane, the molecular weight cut-off of the nanofiltration membrane can be increased, and part of monovalent ions are selectively allowed to permeate while it is guaranteed that small organic molecules are effectively intercepted, so that the nanofiltration membrane still has a high permeation flux under high-salinity water inlet or a high recovery rate, and it is unnecessary to additionally increase operating pressure. By depositing the dense positive charge thin layer on the surface of the loose polyamide separating layer through electrostatic adsorption-chemical crosslinking, interception of the nanofiltration membrane on multivalent cations (such as calcium ions, magnesium ions, heavy metal and other substances harmful to the human body) in water can be easily improved, and drinking water safety can be guaranteed to a great degree; meanwhile, the thickness of the deposition coating can be effectively controlled within a certain range with the electrostatic adsorption technology, and thus substantial increase of permeation resistance can be avoided as far as possible.

The invention belongs to the technical field of sewage disposal technology and particularly relates to a concentrated and integrated sand and water separation device. The concentrated and integrated sand and water separation device aims at separating sand and water in sand and water mixed liquid discharged from a grit chamber of a sewage disposal plant, reinforcing removal of fine sand and reducing organic content on sand surfaces to further release a carbon resource. According to the technical scheme, the concentrated and integrated sand and water separation device comprises a sand concentrator and a sand and water separator; the sand and water separator comprises a collection hopper water tank and a spiral sand washing device; the sand concentrator is connected to the collection hopper water tank. The concentrated and integrated sand and water separation device is used for separating the sand and the water in the sewage disposal plant, reinforcing the removal of the sand, reducing the organic content on the sand surfaces and promoting organic entrapment.

The invention discloses a nanofiltration membrane, a preparation method and application thereof. The nanofiltration membrane comprises a support bottom membrane and an active separation layer arrangedon the support bottom membrane, wherein the active separation layer has an interpenetrating network structure, and the interpenetrating network structure is mainly formed by interpenetrating polyamide formed by an interfacial polycondensation reaction of a polyethyleneimine monomer and an acyl chloride monomer with ultrafine nanofibers. The preparation method comprises the following steps: arranging an ultrafine nano-fiber layer on a micro-filtration membrane to prepare an ultrafine nano-fiber / micro-filtration membrane composite substrate; and carrying out an interfacial polycondensation reaction on a polyethyleneimine monomer and an acyl chloride monomer on the surface of the superfine nanofiber / micro-filtration membrane composite substrate, and carrying out heat treatment to obtain thenano-filtration membrane. The preparation method of the nanofiltration membrane is simple, and the obtained nanofiltration membrane has high flux and high salt rejection performance, so that the desalination energy consumption cost is reduced, and the nanofiltration membrane has a wide application prospect in the aspects of seawater desalination pretreatment, water softening and the like.

The invention relates to a preparation method of a two-dimensional temperature-sensitive metal organic framework nanosheet-based filter membrane. The preparation method comprises the following steps:firstly, inhibiting the growth of metal organic framework nanoparticles in the Z-axis direction by utilizing the interaction of a polymer and the metal organic framework nanoparticles, and modifying the surfaces of the metal organic framework nanoparticles to obtain two-dimensional temperature-sensitive metal organic framework nanosheets; preparing a film, and carrying out surface polymerization.The novel filter membrane has the intelligent property that the flux is variable along with the temperature and the salt concentration. Meanwhile, due to the high specific surface area and high porosity of the two-dimensional metal organic framework nanosheet and the modification effect of the surface polymerization layer, the novel membrane has excellent separation performance of high flux and high interception. The method disclosed by the invention is simple and convenient to operate, environment-friendly and easy for batch and large-scale production, and has a good industrial production basis and a wide application prospect.

The invention provides an initial rainwater pollutant interception facility and an interception operation method. The whole main body of the facility is in barrel shape. Two sides of the upper part of the facility main body are provided with a water inlet pipe and a water outlet pipe. The water inlet pipe is inclined and is inserted in the facility main body and is connected with a peripheral body tangent insertion inner wall of the facility main body. A supporting frame in the facility main body is provided with a diversion cylinder. Rainwater forms an eddy state between a porous inner wall main body and the diversion cylinder, to generate centrifugal force. Foreign matters in rainwater fall in a sediment collection region from a lower ventage of a guide plate, and are discharged by opening a discharge hole. Pollutants intercepted in the porous inner wall are eliminated through microbial decomposition. The facility is simple in structure, good in reliability, and simple in installation and maintenance, and improves an original initial rainwater pollutant interception device, and interception and treatment efficiency on rainwater runoff pollutants is improved. The pollutants intercepted in the porous inner wall are fully decomposed and treated by microorganism, and a filter layer in the water outlet pipe can fully filter rest pollutants. The improved facility main body still maintains to be integrated, and installation and overhaul are convenient, and just regular checking and desilting and pollution discharge are needed.

The invention provides an unpowered rainfall runoff pollutant intercepting facility and a pollutant intercepting operation method. A facility main body is barrel-shaped in the whole, a water inlet pipe and a water outlet pipe are mounted at two sides of the upper part of the facility main body, respectively, the water inlet pipe is inserted into the facility main body in the form of an inclination angle and is connected with the circumferential tangent insertion inner wall of the facility main body, a flow guide barrel is mounted on a support frame in the facility main body, rainwater forms the vortex state between the inner wall of the facility main body and the flow guide barrel, then centrifugal force is generated, sundries in the rainwater fall into a sediment collecting area from a lower leaking hole of a flow guide plate, then a deslagging hole is opened, and the sundries are discharged. The unpowered rainfall runoff pollutant intercepting facility is simple in structure, good in reliability, and simple and convenient to mount and maintain, through the improvement on the original initial rainwater pollutant intercepting facility, the intercepting and processing efficacies for the rainfall runoff pollutants are improved, the improved facility main body is integrated, and is convenient to mount and overhaul, and only regular checking, desilting and pollutant discharge are needed.

The invention discloses a method and device for sterilizing a water body in combination with three-dimensional electrode and photocatalysis, and application of the method and the device. The method comprises the steps of: firstly, treating the water body to be treated by electrochemical reaction of the three-dimensional electrode; and then, sequentially treating the water body by photocatalytic reaction agent under the excitation of ultraviolet light to obtain the sterilized water body. The device for realizing the method comprises a three-dimensional electrode electrochemical sterilization pool and an ultraviolet light catalytic sterilization pool, which are sequentially connected with each other; the two pool walls of the three-dimensional electrode electrochemical sterilization pool are respectively provided with a cathode and an anode, which are connected with a power supply, and the three-dimensional electrode electrochemical sterilization pool is internally provided with three-dimensional electrode filler; and the pool wall of the ultraviolet light catalytic sterilization pool is fixedly provided with a photocatalyst layer, and the ultraviolet light catalytic sterilization pool is internally provided with a plurality of ultraviolet lamps used for exciting photocatalyst. After the technology for combining the three-dimensional electrode sterilization and ultraviolet lightcatalysis is adopted, the lower voltage and the ultraviolet light catalysis is carried out, waste water with higher bacteria-containing concentration can be treated efficiently, and the effect of continuous and efficient sterilization can be achieved by a one-step method, so that the bright and clear in application prospect is realized.

The invention discloses preparation and application of a whisker-shaped ceramic membrane with low cost and high permeability, and belongs to the technical field of preparation of high-permeability membranes. According to the method, tungsten oxide is added to form thewhisker-shaped ceramic membrane; the ceramic membranehas lower mullite forming temperature, and the sintering cost is greatly reduced; higher porosity, higher mechanical strength and better mechanical strength are achieved, and the permeability is improved; and the surface is rougher, so that the wettability of the membrane is effectively enhanced, and the membrane has higher oil pollution resistance in the oil-water separation process. In the preparation process, a phase inversion method or an extrusion molding method is adopted, so that hollow fibrous, tubular or hollow flat-plate-shaped and large-size tubular or flat-plate-shaped whisker structure mullite ceramic membranes can be respectively obtained, and can be used for large-scale industrial application. The whisker-shaped mullite ceramic membrane shows stable high permeation flux and high oil retention rate for oil-water separation (such as high-concentration and high-acid-base environments and complex oily wastewater), and has a wide application prospect.

The invention relates to sulfonated polyethyleneimine and a nanofiltration membrane, and preparation methods thereof. The sulfonated polyethyleneimine is obtained by a ring-opening reaction of polyethyleneimine and sultone. The sulfonated polyethyleneimine is used as a water-phase monomer to prepare the loose nanofiltration membrane through interfacial polymerization. Due to introduction of sulfonic acid groups, the polarity of the monomer is improved, and the solubility of the monomer in an oil phase is reduced, so the process of interfacial polymerization is inhibited; and finally, a polyamide separation surface layer with a loose structure is obtained. Based on the unique structure and properties of the sulfonated polyethyleneimine, the prepared nanofiltration membrane has the characteristics of high water flux, high dye interception and high salt permeation, and is suitable for treatment of printing and dyeing wastewater.

The invention discloses an artificial wetland system and a method for treating wastewater containing nitrogen and phosphor with the artificial wetland system. The system comprises a water distribution region which is used for introducing the wastewater containing nitrogen and phosphor into the artificial wetland system, a functional region which is used for removing nitrogen and phosphor elements in the wastewater and a drainage region which is used for draining nitrogen and phosphor removed wastewater out of the artificial wetland system, which are arranged from top to bottom sequentially. According to the artificial wetland system, the proportion of ion content in the wastewater containing nitrogen and phosphor can be regulated, so that a struvite seed crystal can be formed by the wastewater containing nitrogen and phosphor in the functional region, struvite fertilizer can be effectively formed by nitrogen and phosphor elements and deposited on the filler surface, entrapment, adsorption and enrichment of the system on nitrogen and phosphor elements in the wastewater can be promoted, and the wetland plant roots can constantly decompose and absorb nitrogen and phosphorous substances and constantly generate struvite to achieve dynamic balance. The artificial wetland system can stably run for a long time, has high denitrification and dephosphorization efficiency, can sustainably supply fertilizer to plants, and can meet environment protection requirement and realize resource reasonable utilization.

A biological treatment apparatus of high-concentration organic matter and ammonia nitrogen wastewater is characterized in that the apparatus comprises a reaction container, the internal of the reaction container is divided into a high-efficiency anaerobic chamber in the middle, a short-cut nitrification chamber arranged around the high-efficiency anaerobic chamber and an anaerobic ammoxidation chamber arranged around the short-cut nitrification chamber by separator plates, the high-efficiency anaerobic chamber is sequentially provided with a first water distribution zone, a first reaction zone, a three-phase separation zone and a first water outlet zone from bottom to top, and the first reaction zone is provided with anaerobic granular sludge; the short-cut nitrification chamber is sequentially provided with a second water inlet zone, a second reaction zone and a second water outlet zone from top to bottom, the second reaction zone is provided with a biological filler, the second water outlet zone is provided with an aeration device, and the second water inlet zone communicates with the first water outlet zone; and the anaerobic ammoxidation chamber is sequentially provided with a third water inlet zone, a third reaction zone and a third water outlet zone from bottom to top, the third reaction zone is sequentially provided with anaerobic ammoxidation granular sludge and an anaerobic ammoxidation biological filler from bottom to top, and the third water inlet zone communicates with the second water outlet zone.

The invention relates to a modifier for a filter membrane for filter removal of leucocytes and a modification method of the filter membrane. The modifier for the filter membrane is composed of amidated modified silk fibroin, polyvinyl pyrrolidone and an acrylate copolymer with the mass ratio of (0.05-2):(0.2-1):1, wherein the acrylate copolymer is composed of a methyl methacrylate monomer and a dimethylaminoethyl methacrylate monomer. The modifier for the filter membrane can be dissolved in a polar solvent such as water to prepare a solution, and the filter membrane is subjected to coating treatment by an infiltration modification method; the filter membrane after being treated by the modifier for the filter membrane has relatively good wettability, stability and compatibility, has relatively high filter removal rate on both the leukocytes and platelets, and has relatively low modifier washout rate, and avoids soluble substance pollution.

The invention relates to a preparation method of a hot-method polyvinylidene fluoride hollow fiber membrane for drinking water treatment and belongs to the technical field of membrane separation and drinking water treatment. The preparation method comprises the following steps: drying polyvinylidene fluoride and polyether sulfone; proportionally weighing, stirring and dissolving the polyvinylidene fluoride, the polyether sulfone, polyethylene glycol 400, triethyl phosphate and calcium chloride; putting a product into a double-screw extruder for extrusion to form a hollow nascent fiber; cooling and solidifying the nascent fiber in a cold extraction liquid tank; soaking the nascent fiber into ultrapure water, removing a diluent, and performing airing to obtain the polyvinylidene fluoride hollow fiber membrane. According to the method, raw materials are safe, sanitary and environment-friendly, are high in heat resistance, chemical stability, weather resistance, ozone resistance, ultraviolet radiation resistance and chemical corrosion resistance, and are high-end membrane materials for the drinking water treatment with excellent performance; the hot-method polyvinylidene fluoride hollow fiber membrane is high in retention and stable in performance, produced water is good in quality, and when the membrane is used, yarns are not broken.

The present invention is concerned with the treatment of produced water, obtained from a chemically enhanced oil recovery process using viscosity-increasing polymeric compounds. Said treatment comprises particularly the steps of obtaining a produced water, from an oil-water mixture recovered from an oil-bearing formation, wherein the produced water comprises the viscosity-increasing polymeric compounds; and, of directing the produced water to a specific filtration device, and subjecting the produced water to filtration, for obtaining a retentate stream and a permeate stream. Said process allows particularly obtaining a permeate comprising the viscosity-increasing polymeric compounds, said permeate being substantially free of suspended solids, free oil and emulsified oil.

The invention relates to a rainwater runoff pollution sewage interception facility and a sewage interception operation method. An integrated facility main body is in a barrel shape. Two sides of the upper part of the facility main body are provided with a water inlet pipe and a water outlet pipe. The water inlet pipe has an inclination angle and is inserted in the facility main body, and is tangent with the peripheral body of the facility main body and is inserted into an inner wall. A supporting frame in the facility main body is provided with a guide cylinder. Rainwater forms an eddy state between the inner wall of the facility main body and the guide cylinder, to generate centrifugal force. Foreign matters in rainwater fall into a sediment collecting region from a lower ventage of a guide plate, and the foreign matters are discharged after a slag-drip opening is opened. The facility is simple in structure, good in reliability, and simple in installation and maintenance. Improvement on an original initial rainwater sewage interception device improves interception and processing efficiency of rainwater runoff pollution, and a filter layer in a water outlet pipe can fully filter surplus pollutants, and the improved facility main body still keeps integrated. The facility is convenient in installation and overhaul, and just needs regular checking and dredging and pollution discharge.

The invention belongs to the technical field of sewage treatment, and particularly relates to a preparation method of a polyvinylidene fluoride microfiltration membrane. In the preparation process, polyvinylidene fluoride, additives and polar solvents are used as raw materials to be prepared into membrane casting liquid; then, sequentially through defoaming, coating, gel bath, hole protection, drying and the like, the polyvinylidene fluoride microfiltration membrane is formed. The prepared polyvinylidene fluoride microfiltration membrane has the characteristics of high flux, high retention rate and excellent mechanical property; the preparation technological process is simple and continuous; the industrialization is easy.

The invention discloses a fresh air device and belongs to the technical field of air purification. The fresh air device comprises a heat exchange system, a purification system, a temperature adjustment system and a humidification system; the heat exchange system is used for making fresh air entering the fresh air device from the outdoor and exhaust air discharged from the fresh air device exchangeheat in the fresh air device; the purification system is used for purifying the fresh air subjected to heat exchange of the heat exchange system; the temperature adjustment system is used for heatingand / or cooling the fresh air after heat exchange of the heat exchange system, and the humidifying system is used for dehumidifying fresh air. According to the fresh air device, the cold quantity or heat in the exhaust air can be recycled through the heat exchange system, the temperature and humidity of indoor air can be adjusted to make a user feel comfortable through the temperature adjustment system and the humidification system, energy is saved, and the user experience is good; in addition, the purification system is arranged behind the heat exchange system, after heat exchange and coolingof the high-temperature fresh air and the exhaust air of a fresh air system, the flow speed of the fresh air is reduced, and the purification effect is improved.

The invention discloses a carbon nitride (g-C3N4) nanosheet-based photocatalytic composite membrane and a preparation method and application thereof, and belongs to the technical field of photocatalysis and water treatment. The preparation method comprises the following steps: preparing g-C3N4 nanosheets from dicyandiamide and ammonium chloride, mixing a dispersion liquid of the g-C3N4 nanosheetswith a high polymer material chloromethylated polyethersulfone (CMPES) to prepare a membrane liquid, and carrying out phase inversion to obtain the g-C3N4 nanosheet-based photocatalytic composite membrane. As a composite water treatment technology integrating membrane separation and photocatalysis self-cleaning, the obtained photocatalysis composite membrane has the characteristics of environmental friendliness, low operation cost and high water treatment efficiency, has high pollutant interception and removal rate, good stability and strong anti-pollution performance, and has a wide application prospect in the field of water treatment.

The invention discloses a vertical sieve plate type air purification device, and belongs to the technical field of air purification devices. The vertical sieve plate type air purification device comprises a purifier body, a primary filter element arranged at an air inlet, and a fan arranged at an air outlet, wherein several layers of vertical sieve plates are gradually arranged in the purifier body in an air flow direction; the vertical sieve plates are filled with purifying liquid for purifying the air; each layer of vertical sieve plate supplements liquid through a liquid feeding device communicated with a liquid feeding opening; the liquid feeding opening is arranged above the first layer of vertical sieve plate; a water tank communicated with the liquid feeding device through a motor is arranged below the last layer of vertical sieve plate; a liquid outlet is formed in the purifier body corresponding to a lower wall surface of the water tank, and a backwashing device is also arranged at the same position; the purifying liquid contains an effective catalyst. The vertical sieve plate type air purification device provided by the invention is simple in structure, easy to maintain, low in cost, high in contact possibility between the air and the purifying liquid, small in fluctuation of pressure drop, stable to operate, and strong in processing capability.

The invention relates to a preparation method of a polyvinylidene fluoride hollow fiber ultra-filtration membrane for drinking water treatment and belongs to the technical field of membrane separation and drinking water treatment. The preparation method comprises the following steps: respectively drying polyvinylidene fluoride and polyarylene sulfide sulfone in a drying machine; proportionally weighing the polyvinylidene fluoride, the polyarylene sulfide sulfone, tetraglycol, N-methyl-2-pyrrolidinone and polyvinylpyrrolidone, and putting into a stirring kettle for stirring and dissolving to obtain a uniform blended high polymer solution; extruding the uniform blended high polymer solution through a filter and a spinning pump, and then extruding a hollow nascent fiber from an annular opening mold; performing cooling and solidification through a cold extraction solution; soaking into reverse osmosis water to remove a membrane diluent mixture, and performing airing to obtain a hollow fiber ultra-filtration membrane product. According to the hollow fiber ultra-filtration membrane prepared through the method, raw materials are safe, sanitary and environment-friendly, and are high in heat resistance and chemical stability. The polyvinylidene fluoride hollow fiber ultra-filtration membrane is high in retention, stable in performance and suitable for being applied to municipal drinking water treatment, produced water is good in quality, and when the membrane is used, yarns are not broken.

The invention discloses a low temperature denitration reactor, belonging to the technical field of low temperature flue gas denitration. The invention is mainly to provide the denitration reactor for low temperature denitration technology by a new catalysis method. The reactor is characterized by comprising a vertically installed cuboid-shaped denitration reactor main body, wherein a horizontal flue gas inlet is arranged in the side lower part of the main body, a horizontal flue gas outlet is arranged in the side upper part, and a renewable liquid outlet is arranged at the bottom; a second denitration catalyst packing grid frame, a first denitration catalyst packing grid frame and a preprocessing packing grid frame are arranged inside a main body from top to bottom; a spraying device is arranged above the second and first denitration catalyst packing grid frames and the preprocessing packing grid frame; and a manhole is arranged at the upper side wall of the main body. The reactor integrates flue gas pretreatment, denitration main reaction and catalyst regeneration, has the advantages of convenient operation and small occupied area, and is mainly used for flue gas treatment by using a low-temperature denitration catalyst.

The invention provides a polyvinylidene fluoride hollow fiber membrane and a preparation method thereof. The hollow fiber membrane is a porous structure prepared by taking polyvinylidene fluoride (PVDF) as a raw material under the action of a diluent. The outer surface layer of the porous structure is of a pit structure, and the pit structure comprises a plurality of pits; the diameter of each pit is 0.1 [mu]m-1 [mu]m, a large number of small holes formed by piling PVDF spherocrystals are uniformly distributed in the pits, and the aperture of the small holes is 0.02 [mu]m-0. 04 [mu]m; a spongy macroporous structure with non-uniform pore diameter is arranged below the outer surface layer, the pore diameter of the spongy macroporous structure is gradually changed from the outer surface layer to the inside, and a change value is gradually increased from 1 micron to 10 microns. According to the PVDF hollow fiber membrane with the hourglass-like pore structure, provided by the invention, the effective filtering surface area of the hollow fiber membrane is obviously increased, so the hollow fiber membrane is large in filtering flux and has a good interception effect; namely, the unification of large flux and high interception of the PVDF hollow fiber membrane is realized.

The invention discloses a carbon fiber / polyester hemodialysis membrane and a preparation method thereof, and relates to the field of biological materials. The hemodialysis membrane is a hollow fiber membrane, the diameter of a hollow fiber is 0.5-5 micrometers, the bore diameter of the hollow fiber is 1.4-4.3 micrometers, the wall thickness of the hollow fiber is 35-60 micrometers, the hemodialysis membrane is prepared from components including, by weight, 26-38 parts of polyester, 5-12 parts of carbon fibers, 8-18 parts of acetic acid, 10-17 parts of tetrahydrofuran, 2-5 parts of catalysts and 25-42 parts of solvents. The preparation method of the carbon fiber / polyester hemodialysis membrane includes the preparation steps: (1) preparing spinning solution; (2) performing electrostatic spinning. The carbon fiber / polyester hemodialysis membrane is prepared by an electrostatic spinning process, the diameter of the hollow fiber and the bore diameter of the fiber membrane are ideal, the wall thickness is proper, the hemodialysis membrane has fine biological compatibility, allergy and coagulation are greatly reduced, and the hemodialysis membrane is ideal.