2102 results about "Membrane surface" patented technology

The invention relates to the field of wastewater treatment, and provides an industrial wastewater membrane process intelligent optimization method and system based on multi-dimensional data modeling. The method comprises the following steps: acquiring wastewater quality parameters of a target scene and a production line equipment state in real time through a multi-dimensional sensor network, and constructing a digital twinborn model of a wastewater treatment system in the target scene; the membrane surface pollution type of each node in the wastewater treatment system is identified through a digital twin model, and the inner membrane pollution evolution condition in the future preset duration is predicted; a multi-strategy evolutionary reinforcement learning algorithm is adopted, the wastewater quality parameters, the production line equipment state and the membrane pollution prediction result are combined, multi-target dynamic optimization is conducted on a wastewater treatment system through a multi-agent collaborative decision-making algorithm, an optimization strategy is generated based on the multi-target dynamic optimization result, and membrane process operation parameters and production control parameters are dynamically adjusted. According to the method, real-time intelligent adjustment of membrane process operation can be realized, the stability of membrane process operation is guaranteed, and the treatment efficiency of membrane process operation is improved.

The invention discloses a defoaming agent foam distribution analysis method based on image feature recognition, and particularly relates to the field of industrial foam behavior perception and analysis for recognizing an image object with a random mode as a feature, and the method comprises the following steps: obtaining a foam image sequence in a target area, and collecting the foam image sequence through imaging equipment, the image frames of the foam image sequence have time continuity; and performing disturbance feature extraction operation on the foam image sequence to obtain local disturbance speed information, membrane surface tension change trend information and form boundary fluctuation information of the foam edge within a preset time. According to the method, foam structure disturbance characteristics are extracted from an image time sequence, a structure evolution graph memory bank is constructed, and irregular sudden change image behaviors are identified in combination with a trend matching mechanism, so that dynamic perception and abnormal response of a sudden foam state without prior support are realized, and the problem that a random mode foam state cannot be identified is solved.

The invention discloses a modification method of a PVDF (Polyvinylidene Fluoride) separation membrane, and belongs to the technical field of water treatment. The modification method provided by the invention comprises the step of impacting the PVDF separation membrane by adopting high-pressure liquid, so that high-pressure micro-droplets are in high-speed friction with the surface of the PVDF separation membrane. According to the modification method provided by the invention, the hydrophilicity, the surface potential and the dye retention rate of the PVDF separation membrane can be effectively improved.

The invention relates to a preparation method for improving a sodium alginate pervaporation membrane by using a two-dimensional leaf-shaped zeolite imidazole framework (ZIF-L) material, and particularly relates to a preparation method for improving a sodium alginate pervaporation membrane by using a two-dimensional leaf-shaped zeolite imidazole framework (ZIF-L) material. The pervaporation mixed matrix membrane comprises a base membrane and a separation layer membrane, the base membrane adopts a polyacrylonitrile (PAN) membrane, and the separation layer is composed of ZIF-L and sodium alginate. According to the invention, the distribution of ZIF-L in the membrane is improved, directional arrangement is formed, and the separation effect and selectivity of the composite membrane are improved. A novel process is adopted, the defect problem of the ZIF-L-SA membrane is eliminated, the continuous ultrathin ZIF-L membrane is prepared through a secondary seed growth method, and the performance of the two-dimensional ZIF-L membrane is improved. The ZIF-L synthesis conditions are mild, the method is simple, hydrophilic modification of the membrane surface is achieved, an internal water molecule transmission channel is constructed, and the separation factor and stability of the membrane are improved. The prepared high-flux pervaporation membrane has a wide application prospect.

The invention discloses a multifunctional electronic product screen protective film and a preparation method thereof. The protective film comprises a modified base film and a multifunctional composite layer compounded on the surface of the modified base film, the multifunctional composite layer comprises an elastic buffer layer and a self-repairing layer which are sequentially arranged from inside to outside; wherein the elastic buffer layer is an elastic buffer layer with gradient density; the elastic buffer layer comprises the following components in parts by weight: 100 parts of a thermoplastic polyurethane elastomer, 15-25 parts of hollow glass microspheres, 10-15 parts of polyethylene glycol and 3-6 parts of an isocyanate cross-linking agent; the self-repairing layer comprises the following components in parts by weight: 100 parts of a dynamic reversible covalent bond polymer, 30-40 parts of phase change material microcapsules, 10-15 parts of nano cellulose, 5-8 parts of a near-infrared photosensitive initiator and 2-4 parts of an antioxidant. Compared with the prior art, the protective film provided by the invention has excellent scratch self-repairing performance, good adhesion and high anti-explosion screen performance.

The preparation method comprises the following steps: obtaining a ZnO nano-particle seed crystal layer by a dip-coating-calcining method, and growing the ZnO nano-particle seed crystal layer on a porous ceramic membrane; inducing growth of ZnO nano-clusters on the surface of the ceramic membrane on which the ZnO nano-particles grow and in pore channels of the ceramic membrane through a hydrothermal reaction; and finally, soaking the ceramic membrane on which the ZnO nano-cluster grows in an n-octyltriethoxysilane-absolute ethyl alcohol solution, and carrying out silane chemical grafting treatment. A firm micro-nano composite multilevel structure is obtained on the surface and in pore channels of the ceramic membrane after modification through the method, meanwhile, the surface free energy of the surface and pore channels of the ceramic membrane is reduced through n-octyltriethoxysilane, the surface and the pore channels of the ceramic membrane have super-hydrophobic performance, and the preparation method is simple in preparation process, short in period and suitable for industrial production. And the universality is high.

The invention relates to the technical field of skin-touch coatings, in particular to a preparation method of a paint film of an excimer UV skin-touch coating which comprises the following components in percentage by mass: 30%-90% of resin, 5%-40% of monomers, 0.01%-10% of a photoinitiator and 0.01%-10% of an auxiliary agent, the prepared paint film is soft and smooth in surface, low in glossiness, good in wear-resistant effect and good in chemical resistance, the uneven structure formed by the difference of curing of the surface layer and the inner layer of the paint and the effect of microcosmic wrinkles caused by shrinkage of the surface layer achieves the effects that the surface glossiness is low, and the glossiness is lower than 10 degrees when the incident angle is tested to be 60 degrees; and the generated wrinkles are very fine and are naturally generated radians, so that the hand feeling is very smooth, the dynamic friction coefficient of the surface is very low, and the wrinkles on the surface of the coating are caused because the surface curing speed and the bottom curing speed are different, the surface shrinkage is large and the inside shrinkage is small.

The invention relates to the technical field of water resource purification, in particular to a control method and equipment of a reverse osmosis water purification system.The control method comprises the steps that firstly, on the fluctuation dimension of the pre-membrane pressure, the adjusting requirement of the frequency of a high-pressure pump is preliminarily determined on the dimension of the pre-membrane pressure according to an obtained pressure fluctuation index; determining a membrane resistance increase factor representing the pollution state of the reverse osmosis membrane on the basis of the transmembrane pressure difference on the dimension of separation function failure of the reverse osmosis membrane; finally, a membrane separation abnormal value is comprehensively represented by combining a pressure fluctuation index and a membrane resistance increase factor, and a purified water recovery rate is introduced to a membrane separation result end, so that the finally obtained frequency reduction demand degree is more accurate, and the control effect of the reverse osmosis water purification system is improved; therefore, the stable, efficient and sustainable operation of the reverse osmosis water purification system can be ensured while the membrane surface pollutant deposition driving force can be effectively reduced and the membrane pollution speed can be slowed down.

The invention discloses a method for preparing a polymer anti-pollution membrane, which is characterized in that a'fluorine-containing polymer / styrene-maleic anhydride 'porous membrane is prepared by taking a styrene-maleic anhydride copolymer and a fluorine-containing polymer as base materials and adopting a thermally induced phase separation technology. And loading chitosan on the surface of the porous membrane by utilizing a chemical reaction between anhydride on the surface of the membrane and a small part of amino groups in a chitosan chain. The chitosan molecular chain with pH responsiveness not only improves the hydrophilicity of the membrane and slows down the deposition of inorganic scales on the surface of the membrane, but also has the conformation subjected to'curl-stretch 'reversible transformation (similar to'curl-stretch' motion of earthworms in soil so as to soften the soil) in the'acid washing-alkali washing 'cleaning process of the membrane; hardened inorganic scale deposited on the surface of the membrane becomes loose, the binding force between the inorganic scale and the surface of the membrane becomes weak, and the inorganic scale can be effectively removed through surface water cleaning in the follow-up process. The prepared cleaning agent has the advantages of being high in pollution resistance, good in inorganic dirt removal effect after cleaning and the like.

The invention discloses a preparation method of a photocatalytic nanofiltration membrane based on IL-GQDs. The method comprises the following steps: pretreating bagasse, and applying the pretreated bagasse and imidazole ionic liquid (IL) to preparation of ionic liquid functionalized graphene quantum dots (IL-GQDs); the IL-GQDs are uniformly distributed on the surface of the base membrane by utilizing a vacuum-assisted low-temperature interfacial polymerization technology to form an ultrathin photocatalytic active layer; and finally, curing and cleaning to obtain the photocatalytic nanofiltration membrane based on the IL-GQDs. According to the prepared IL-GQDs, the membrane surface is endowed with high specific surface area and excellent photocatalytic activity, and meanwhile, an additional water transmission channel can be established under the condition that the pore diameter of the membrane is not changed, so that the problem of trade-off of a traditional membrane is solved. In addition, through combination of low-temperature and vacuum-assisted interfacial polymerization technologies, the membrane structure is more uniform and compact, defects on the surface of the membrane are reduced, and the stability and the anti-pollution capacity of the membrane are improved. The membrane disclosed by the invention shows relatively high water flux, salt recovery rate and long-term stability in water treatment application.

The invention discloses a preparation method of a crown ether functionalized anti-pollution nanofiltration membrane, which comprises the following steps: soaking a membrane of a commercial nanofiltration membrane in pure water, and coating the surface with a double-end epoxy compound ethanol solution; uniformly coating the surface of the membrane with an aza 12-crown-4 methanol solution; and drying the membrane in an atmosphere of 40-90 DEG C to obtain the crown ether functionalized anti-pollution nanofiltration membrane. The nano-filtration membrane is realized by chemically grafting aza 12-crown-4 on the membrane surface of a commercial nano-filtration membrane by utilizing a double-end epoxy compound; compared with a traditional nanofiltration membrane, the crown ether functionalized nanofiltration membrane provided by the invention has the advantages that the electronegativity of the surface is reduced, and the surface is similar to an aquatic plant molecular brush structure, so that the deposition of pollutants on the surface of the membrane can be effectively improved, and the anti-pollution performance of the membrane is enhanced; meanwhile, due to the complexing effect of 12-crown-4 molecules on lithium ions, the lithium ions can be effectively captured, concentration polarization of the lithium ions on the surface of the diaphragm is improved, and then the magnesium-lithium separation efficiency of the diaphragm is improved.

The invention relates to the technical field of water treatment, in particular to a high-recovery-rate short-process salt-tolerant reverse osmosis system and treatment method.The system comprises a pretreatment unit, a sensor monitoring unit, a self-adaptive pressure-flow coupling control unit, an intelligent operation and maintenance unit and a gradient boosting reverse osmosis membrane set. According to the invention, ultrahigh recovery rate and desalination performance are realized, gradient boost membrane module design is combined with concentration polarization inhibition technology, membrane surface flow state distribution is optimized, osmotic pressure influence is significantly reduced, pressure-flow coupling control and concentrated water excess pressure energy recovery technology are integrated, energy dynamic cyclic utilization is realized, energy consumption is reduced, and the method is suitable for industrial production. By monitoring the membrane flux attenuation rate and the transmembrane pressure difference in real time and dynamically optimizing a pulse cleaning strategy, dynamic optimization of high-salinity wastewater treatment is realized, and the problems of low recovery rate, high energy consumption and quick membrane pollution in high-salinity wastewater treatment are solved.

The invention discloses a silicon dioxide reinforced high-hydrophobicity polyvinylidene fluoride membrane as well as a preparation method and application thereof, SiO2 nanoparticles are taken as a mechanical reinforcing agent and a structure regulator and are directly added into a membrane casting solution system, and solid-liquid phase separation is preliminarily induced on the surface of a primary membrane in combination with non-solvent spraying ethanol, so that the high-hydrophobicity PVDF membrane is successfully prepared. A unique multi-stage micro-nano structure consisting of mutually connected spherocrystals is constructed on the surface of the membrane, the hydrophobicity, aperture, porosity and mechanical property of the membrane are effectively improved, and the membrane shows excellent and stable separation performance in performance tests of seawater desalination and erythritol concentration, and has good application prospects in seawater desalination and erythritol concentration. The method shows huge application potential in the fields of wastewater treatment, food production and the like.

The invention discloses a composite isolating membrane based on synergistic modification of a porous material and an ionic conductor material and a preparation method of the composite isolating membrane. The composite isolating membrane comprises a base membrane and a coating which is coated on the surface of the base membrane and comprises a porous material and an ion conductor material. The composite isolating membrane has multiple ion transmission paths including ion diffusion or migration transmission, lattice diffusion transmission and ion seepage transmission, the ion transmission efficiency is synergistically enhanced, and the problem that the ion transmission mechanism is single is solved. In addition, the composite separation membrane has accessory functionality, and migration of transition metal can be inhibited. The composite isolating membrane disclosed by the invention is suitable for a high-capacity-density and high-rate battery system, and meets the requirements of battery development.

The invention discloses a flexible pressure sensor with a multistage hemispherical structure and a preparation method thereof, the sensor comprises an electrode layer, and an upper friction layer, a separation layer and a lower friction layer which are sequentially arranged below the electrode layer from top to bottom, the separation layer is used for providing a space for full contact and separation of the upper friction layer and the lower friction layer, and the separation layer is used for providing a space for full contact and separation of the upper friction layer and the lower friction layer. And the lower friction layer is formed by a multi-stage hemispherical structure constructed on the surface of a flexible film. The sensor has the remarkable effects that benefited from the characteristics of a triboelectric sensing mechanism, the sensor has the advantages of self power supply, stable output and simple structure, and meanwhile, the upper friction layer and the lower friction layer of the sensor are in step-by-step contact under the action of pressure through the surface microstructure of the lower friction layer of the multi-stage hemispherical structure; the compressibility is enhanced, and the contact and separation process of the sensor is optimized, so that the sensitivity of the sensor is improved.

The invention discloses an advanced treatment and recycling method for cold-rolled silicon steel magnesium oxide wastewater, and particularly relates to the technical field of wastewater treatment. Through pH adjustment, coagulation pretreatment, pre-membrane fine filtration and medicament stabilization of wastewater, stable control of inlet water quality is realized; a two-stage reverse osmosis system is combined with a dynamic flow and cross flow structure, so that the risks of concentration polarization and local stress corrosion are remarkably inhibited; by combining real-time monitoring of membrane surface pressure difference and recovery rate and an intelligent algorithm, self-adaptive optimization regulation and control of operation parameters of the system are realized; according to the method, the problems of serious membrane pollution, poor system stability, low recycling efficiency and the like in the prior art are effectively solved, and the wastewater resource utilization level and the system operation safety are remarkably improved.

The invention relates to a base membrane for a composite current collector based on SiO2 nano composite modification and a preparation method of the base membrane. Synergistic modified nano SiO2 is compounded with aluminum hypophosphite, montmorillonite and the like to form modified auxiliary particles, the modified auxiliary particles and PET master batches are subjected to blending extrusion, and meanwhile, the surface of the base membrane is coated with a modified coating containing nano SiO2, so that the composite current collector is obtained. The mechanical property, the thermal stability and the flame retardance of the base film are obviously improved.

The invention discloses a gradient membrane based on continuous distribution of PVDF-HFP-silicon dioxide electronic injection microspheres and a construction method of the gradient membrane, and belongs to the field of gradient membranes, an improved electrostatic spinning and electrostatic spraying technology is utilized, a PVDF-HFP fiber membrane is prepared through the electrostatic spinning technology, PVDF-HFP / SiO2 composite microspheres are electrostatically sprayed, and a collector receiving device is combined, so that the gradient membrane is obtained. The traction speed change of the substrate film is controlled on the blade electrode, and a wettability gradient film with the continuously-changed surface appearance is constructed; on the surface of the prepared fiber membrane, the distribution form of the polyvinylidene fluoride-hexafluoropropylene / silicon dioxide composite microspheres on the surface of the membrane is in gradient change, a microstructure with continuous change is constructed, the contact angle of the fiber membrane is increased from 128 degrees to 153 degrees along with the change of the surface position, and a gradient surface gradually changing from hydrophobicity to super-hydrophobicity is obtained. And the preparation method has an excellent application prospect in the field of gradient films, bubble transmission and bubble micro-reaction.

The invention relates to the field of decorative films, in particular to an indented pattern color scraping decorative film and a preparation method thereof.The indented pattern color scraping decorative film comprises a skin feeling functional layer, a pattern developing layer, a supporting strengthening layer and a coloring strengthening layer, the skin feeling functional layer, the pattern developing layer and the supporting strengthening layer are composited into an integrated structure through hot pressing, and micron-sized air guide grooves are formed in the bonding faces of all the layers; the air guide grooves are arranged in parallel along the extending direction of the dimpled grains, the 60-degree glossiness of the surface of the decorative film is less than 3GU, the pencil hardness is greater than 1H, and the texture spacing difference between the outline edge of the dimpled grains and the printed pattern layer is 0.1-0.5 mm, so that the decorative film is endowed with excellent stereoscopic visual effect and physical property. The dimpled grain structure in the skin-touch functional layer is directly formed on the surface of the skin-touch coating, the problem of interlayer dislocation caused by traditional composite embossing is avoided, it is ensured that the dimpled grain outline is clear, the peeling strength between layers is high, bonding is tighter, and no bubble is left on the bonding face between the layers.

The invention relates to the technical field of preparation of medical supplies, in particular to a surgical membrane and a preparation process. During specific use, firstly, a polyurethane base membrane is selected and subjected to plasma treatment; spraying a nano SiO2 dispersion liquid containing a photoinitiator on the surface of the treated polyurethane base film, and then performing ultraviolet patterning irradiation to form a micro-bulge structure to obtain a base material layer; projecting the colloidal fluid to a temperature gradient mask through a digital micromirror device, so that the colloidal fluid is subjected to regional thermal polymerization on the substrate layer to form an intelligent adhesive layer with viscosity gradient; by adopting an aerosol jet printing technology, super absorbent fibers and polyvinyl alcohol-borax dynamic crosslinking hydrogel are co-deposited to form a drainage layer, so that the technical problems that a surgical membrane prepared by a surgical membrane preparation mode in the prior art is inflexible in adhesion and poor in surface structure performance, and a preparation process is difficult to accurately control are solved.

The invention relates to the technical field of water treatment, and provides a reverse osmosis membrane cleaning method, a cleaning agent composition and application. According to the method, whether cleaning is needed or not is determined by comparing initial operation parameters and current operation parameters of a system; the pollutant type is accurately judged by observing the appearance characteristics of the membrane surface and detecting related index parameters; and selecting a corresponding cleaning agent formula according to the pollutant type, and sequentially performing physical washing and chemical cleaning. The cleaning agent composition comprises a biological pollution cleaning agent, an organic pollution cleaning agent and / or an inorganic scaling cleaning agent. By establishing a scientific pollution diagnosis system and a targeted cleaning strategy, the problems of fixed cleaning scheme and low pertinence in the prior art are solved, the pressure difference recovery rate after cleaning can reach 90% or above, the desalination rate recovery rate can reach 99% or above, the cleaning efficiency is remarkably improved, the operation cost is reduced, and the service life of the membrane is prolonged.

The invention discloses an MLCC release film base film and a preparation method thereof, and relates to the technical field of release films, the MLCC release film base film comprises a core layer and a functional coating layer arranged on the outer surface of the core layer; the core layer is prepared from the following raw materials: PET (Polyethylene Terephthalate) resin, functional polyester containing triazolyl tetrafluorophenyl, a coupling agent, reinforced fibers, an antioxidant and a lubricant; the functional coating layer is prepared from the following components: hydroxyl-terminated hyperbranched polyester, isocyano ethyl methacrylate, vinyl trimethoxy silane, nano filler, 3, 3 '-diamino-4, 4'-difluorodiphenyl sulfone, 2, 2 '-bis (trifluoromethyl) diaminobiphenyl, a photoinitiator, a catalyst A and a diluent. The base film is low in surface roughness and warping degree, good in high temperature resistance, high in flatness and appropriate in stiffness.

The invention relates to the technical field of reverse osmosis membranes, and particularly discloses an anti-pollution reverse osmosis membrane and a preparation method thereof.The preparation method comprises the steps that organic amine and organic acyl chloride are used for conducting interfacial polymerization reaction on a bottom membrane to prepare a polyamide layer; the photoinitiator containing amino or phenolic hydroxyl reacts with acyl chloride groups left on the polyamide layer after interfacial polymerization, and the photoinitiator is introduced into the surface of the film; pouring a zwitterionic solution on the surface of the membrane at a constant speed, and irradiating under ultraviolet to initiate a polymerization reaction; performing heat treatment on the membrane in a drying oven to obtain the anti-pollution reverse osmosis membrane. The zwitterionic polymer is efficiently grafted on the surface of the membrane by utilizing a photo-initiation free radical polymerization strategy, compared with a traditional grafting method, the operation process is simple, the grafting speed is high (within 5min), the use of an organic solvent is reduced, and the prepared reverse osmosis membrane has excellent anti-pollution performance and huge industrial application potential.

The invention discloses a preparation method and device of a composite current collector, and the preparation method of the composite current collector comprises the following steps: carrying out baking treatment on a polymer film raw material to obtain a base film; the preparation method comprises the following steps: adding a pre-plating layer on the surface of a base film through pre-plating treatment, carrying out film plating treatment on one side, far away from the base film, of the pre-plating layer, and plating a metal thickening layer to obtain a base material; winding the base material to obtain a roll material, and after winding of the roll material is completed, slitting the whole roll material through a slitting machine to obtain a sub-roll material; and carrying out surface modification treatment on the split coil material to obtain the composite current collector. According to the preparation method of the composite current collector, a single evaporation process is adopted for film coating, the process is simple, the film coating efficiency is high, the film forming quality is high, the film coating efficiency is improved through one-time film coating on the front face and the back face, meanwhile, the interface bonding force can be improved through pre-coating in an induction type heating mode, and the film forming quality is improved. And the coating efficiency is ensured, and the coating quality is improved.

The invention discloses an automatic pure water ultrafiltration treatment device, and relates to the technical field of pure water graded filtering and cleaning, the automatic pure water ultrafiltration treatment device comprises a filtering bin, a pure water liquid injection device is mounted on one side of the upper surface of the filtering bin, and a cleaning liquid injection device is mounted on the other side of the upper surface of the filtering bin; compared with the prior art that pure water is pressurized to an ultrafiltration membrane in a fixed mode for ultrafiltration of the pure water, the rotation direction of the motor is automatically recognized and controlled through the sensor, so that the liquid spraying chamber can conduct ultrafiltration at different positions and heights of the ultrafiltration membrane cylinder, and excessive accumulation of the pure water on the surface of the membrane can be avoided; meanwhile, the membrane surface can be cleaned and maintained in time, the service life of the ultrafiltration membrane can be remarkably prolonged, and the replacement cost can be reduced. Compared with fixed pressurization, the automatic adjusting system can be flexibly adjusted according to different water quality, water quantity and treatment requirements. Due to the flexibility, the system can better adapt to various complex and changeable working environments, and the overall treatment effect is improved.

The invention provides a reverse osmosis membrane cleaning system which is characterized in that a variable-frequency water pump control system is adopted to adjust water flow momentum according to cleaning parameters output by a matching algorithm, differential impact strength control of different areas on the surface of a membrane is realized through a flow adjusting valve group, and a stress distribution mode adaptive to pollution distribution is obtained; mechanical stress data of the membrane surface in the cleaning process are collected in real time through a membrane material stress monitoring sensor, if the stress value exceeds a membrane material safety threshold value, a stress protection mechanism is triggered, and the impact strength of a corresponding area is automatically reduced; establishing an adaptive parameter optimization algorithm according to pressure feedback data and a pollutant stripping effect evaluation result in the cleaning process, and calculating a parameter adjustment scheme of the next cleaning period through a tradeoff function of the cleaning effect and mechanical damage; a membrane performance degradation prediction model is established through accumulation of historical cleaning data, the remaining service life of a membrane material is predicted according to accumulated mechanical stress and cleaning frequency data, and a quantitative judgment basis of the membrane replacement opportunity is obtained.

The invention provides a composite nanofiltration membrane as well as a preparation method and application thereof, and the preparation method comprises the following steps: reacting a water phase solution and an oil phase solution on the surface of a base membrane to obtain a primary composite nanofiltration membrane; wherein the water phase solution contains piperazine and polyacrylamide, and the oil phase solution contains trimesoyl chloride. The nanofiltration membrane provided by the invention is high in pure water flux, good in membrane surface hydrophilicity, strong in pollution resistance, high in mechanical strength and durability, low in cost and capable of stably running for a long time.

The utility model discloses a membrane surface greasy dirt detection and cleaning system, which comprises a greasy dirt detection mechanism arranged on one side of a membrane surface and used for marking and detecting greasy dirt on the membrane surface; the oil stain cleaning mechanism is arranged on one side of the membrane surface and is used for removing the oil stain marked by the oil stain detection mechanism; the oil stain detection mechanism detects and marks oil stains attached to the membrane surface, and the oil stain cleaning mechanism correspondingly cleans according to mark points, so that the oil stains attached to the membrane surface are removed; therefore, the oil stain is prevented from polluting the membrane surface, reducing the surface energy of the membrane surface and influencing the performance of the lithium battery.

The present invention discloses a method for synergistically preparing a superhydrophobic membrane by spray-induced nonsolvent phase inversion and click chemistry. The method uses a polymer with a polyvinylidene fluoride as the main structure as a raw material, constructs a micro-nano hierarchical structure in bulk by the spray-induced nonsolvent phase inversion method, and covalently bonds a low surface energy substance to the membrane surface with the assistance of click chemistry technology to achieve the superhydrophobicity of the membrane. The superhydrophobic membrane of the present invention can resist the wetting of liquids with different surface tensions, has good anti-wetting and anti-inorganic fouling properties as well as excellent wastewater treatment capabilities, and can be applied to fields such as membrane distillation seawater desalination, deep treatment of shale gas wastewater and clean water regeneration, etc., broadening the types and application ranges of MD membrane materials.

The present invention relates to the technical field of nanofiltration membranes, and particularly relates to a preparation method for a nanofiltration membrane for regulating and controlling membrane surface charges. The preparation method comprises: step 1: (1) sequentially adding piperazine, a fiber additive, an ionic liquid and polyvinyl pyrrolidone into deionized water to obtain a water phase; and (2) adding trimesoyl chloride into normal hexane to serve as an oil phase; step 2, dipping a base membrane in the water phase for 1-3 minutes, and removing the redundant water phase; transferring same into the oil phase and subjecting same to polymerization for 2-3 minutes, and removing the redundant solution; and curing same at 80-85ºC for 5-6 minutes, and dipping same in deionized water for 1-2 days, so as to obtain a composite base membrane; and step 3, firstly placing the composite base membrane in a sodium hypochlorite solution for a primary post-treatment, and cleaning same; and transferring same into a sodium hydrosulfide solution for a secondary post-treatment, washing same until neutral, soaking same in deionized water for 1-3 days, and drying same to obtain a nanofiltration membrane.