1641results about "Reverse osmosis" patented technology

The invention relates to a composite reverse osmosis membrane acidic cleaning agent, a preparation method and a cleaning process thereof, and belongs to the technical field of environment-friendly water treatment. The cleaning agent comprises the following components in percentage by mass: 4-8% of inorganic acid, 20-40% of organic acid, 1-3% of a surfactant, 0.5-1% of a chelating agent, 0.5-1% of a compound corrosion inhibitor and the balance of deionized water. The composite corrosion inhibitor is formed by compounding 2-mercaptobenzothiazole and the like according to a specific mass ratio, the molecular weight of polyaspartic acid is 5000, and the molar ratio of Zn to Mo in the zinc-molybdate compound is 2: 1. The preparation method comprises the following four steps: firstly preparing a compound corrosion inhibitor premix, then preparing an acidic base solution, and then sequentially adding the components to finally obtain the cleaning solution. According to the cleaning process, a cleaning agent and deionized water are mixed, the membrane flux recovery rate is larger than or equal to 85% through cleaning of a specific process, the reverse osmosis membrane can be effectively cleaned, and the performance of the reverse osmosis membrane can be recovered.

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 relates to the technical field of membrane separation and seawater desalination, in particular to a high-boron-removal-rate reverse osmosis membrane and a preparation method and application thereof. The polyamide reverse osmosis membrane with at least 70% nodular areas on the surface is prepared by introducing the ethylenediamine tetraacetic acid metal salt into the water phase solution as a complexing additive, and the boron removal rate of the membrane can be improved on the basis of ensuring the retention rate and flux of the membrane.

According to the efficient water treatment system based on the reverse osmosis membrane and the control method provided by the invention, gradient anti-pollution membrane arrangement and reconfigurable intelligent waterway design are creatively combined, so that a foundation is laid for high-flux and low-pollution operation from a physical structure; meanwhile, a full-closed-loop intelligent control system is constructed, and by fusing fuzzy logic, an optimization algorithm and a neural network prediction model, the system can integrate multi-dimensional information such as inlet water quality, membrane pressure difference and water yield, judge pollution risks in real time and adaptively and seamlessly switch among a high recovery mode, a segmented flushing mode and a prediction cleaning mode, so that the system is high in recovery efficiency and high in reliability. Meanwhile, parameters such as pump frequency and valves are dynamically optimized to find an optimal balance point of recovery rate and energy consumption; according to the invention, the recovery rate can be stably improved, the membrane pollution rate is greatly reduced, the chemical cleaning period and the service life of the membrane element are prolonged, and finally, the comprehensive operation and maintenance cost of the system is remarkably reduced while the water treatment efficiency and the water quality safety are improved.

The present invention relates to a method for automated data processing to assess the state of multiple filtration membranes used in liquid filtration. The method involves receiving data from state sensors positioned within or near a set of membranes, which process incoming water into permeate and concentrate flows. This data, collected as time series at predefined frequencies, pertains to external physical parameters. An operating indicator is determined from this data, forming a second time series. Both the first and second time series are recorded as point clouds over a specified acquisition period. An intermediate operating indicator is generated, representing the state of new, clean, or cleaned membranes, using a learned normalization model. Finally, a normalized operating indicator is produced, characterizing membrane fouling and aging, independent of environmental variations, and forming a third time series. This method enhances the accuracy of membrane state assessment in filtration systems.

A membrane includes a polysulfone-based support, a polydopamine (PDA) layer disposed on a surface of the polysulfone-based support, and a silver / polydopamine (Ag / PDA) composite layer disposed on a surface of the polydopamine layer. The polysulfone-based support has a pore size of up to 600 nanometers (nm). The Ag / PDA composite layer contains core-shell structure particles and spherical particles. The core-shell structure particles have a silver nanoparticle core and a polydopamine shell. The spherical particles are silver-decorated polydopamine particles. The membrane can at least partially separate an Erichrome Black T (EBT) dye from an EBT dye / salt containing mixture by rejecting the EBT dye and allowing the EBT dye / salt containing mixture to pass through the membrane.

A membrane made of a polymeric support, and an active layer with a polyamide grafted with a copolymer on the polymeric support. The copolymer is reacted units of a diallyldimethylammonium chloride (DADMAC), 3-(N,N-diallyl-N-methylammonio)propanesulfonate (DAMAPS), and N,N-diallyldodecane-1,12-diamine (DADA), and the copolymer is grafted to the polyamide with a linking molecule. Further, a method of making the membrane by dissolving an amine and the copolymer in water to form an aqueous solution, dissolving TMC in an organic solvent to form an organic mixture, pouring the aqueous solution onto a polymeric support and then pouring the organic mixture onto the same support for form a coated support, and heating the coated support to form a membrane.

The invention relates to the technical field of data processing, and discloses an automatic control method and system for wastewater desalination treatment based on the Internet of Things. The method comprises the following steps: acquiring a membrane surface image, an interface potential, an infrared spectrum, a transmembrane pressure difference, a feeding flow rate and a flocculation image; calculating a salt gradient attention feature vector according to the salt concentration difference value and the Beckey number; inputting the multi-modal data into a membrane pollution time sequence memory network to obtain a pollution development rate and a flocculant adding proportion; extracting a floc particle size parameter to obtain a flocculation effect score; and constructing a multi-objective function optimization solution to obtain a control instruction. The salt gradient attention mechanism and the membrane pollution time sequence memory network are introduced, and visual image recognition and multi-modal data fusion are combined, so that the problems of inaccurate membrane pollution state evaluation, low intelligent level of a control algorithm and insufficient multi-target collaborative optimization capability in the prior art are solved; the automation level and the treatment efficiency of wastewater desalination treatment are improved.

The invention relates to the technical field of reverse osmosis membranes, in particular to a multilayer composite anti-biological-pollution reverse osmosis membrane and a preparation method thereof. The reverse osmosis membrane is prepared by the method. The method comprises the following steps: immersing a base membrane into a prepared water phase solution, and sequentially carrying out first immersion treatment and drying treatment in the shade to obtain a first membrane sheet; immersing the first membrane into a prepared organic phase solution, removing the redundant organic phase solution on the first membrane after second immersion treatment, and obtaining a second membrane after interface reaction; and immersing the second membrane into a prepared antibacterial metal ion solution, and carrying out complexation reaction to obtain the multi-layer composite anti-biological-pollution reverse osmosis membrane. According to the invention, the multilayer composite anti-biological pollution reverse osmosis membrane with prolonged antibacterial activity and improved membrane separation performance can be prepared.

The invention provides an intelligent maintenance cleaning device for nanofiltration membrane pollution control and a method thereof, and solves the problems of low maintenance cleaning efficiency, poor adaptability of cleaning parameters and pollution conditions and frequent chemical cleaning of an existing nanofiltration system. Belongs to the technical field of membrane pollution control. According to the invention, the filtering system, the cleaning system and the intelligent decision-making module are integrally designed, so that the closed-loop control of the whole process of real-time monitoring, pollution identification, intelligent decision-making and automatic cleaning of the running state of the nanofiltration membrane is realized. The cleaning effect gating memory neural network model is used as a membrane pollution prediction model, membrane pollution can be accurately predicted, and key cleaning nodes can be identified. The optimal membrane cleaning parameters are generated by adopting a non-dominated sorting genetic algorithm, the usage amount of chemical agents and the cleaning cost are reduced, and the membrane pollution control effect is improved. The invention is applicable to the field of drinking water treatment.

The invention relates to the technical field of membrane separation and water treatment, in particular to an anti-pollution polyurea composite reverse osmosis membrane as well as a preparation method and application thereof. According to the preparation method, a polyamine monomer of a water phase solution and an aromatic polyisocyanate monomer of an organic phase solution are used for constructing a polymerization reaction system to form a urea bond structure, and terminal sealing treatment is cooperatively performed on a polyurea selection layer, so that the compact, flat and hydrophilic polyurea selection layer can be prepared. And the preparation method is simple, mild in condition, low in energy consumption, robust in process, wide in parameter window and suitable for large-scale production. The prepared anti-pollution polyurea composite reverse osmosis membrane has excellent anti-pollution performance and separation performance, can achieve excellent balance between maintenance of initial flux and long-term stability, and has excellent anti-pollution performance and separation performance. The reverse osmosis membrane shows low irreversible pollution rate and good cleaning recoverability to organic / inorganic typical sewage plugging substances, can well meet industrial requirements, and has a good application prospect.

The invention discloses a hollow fiber nanofiltration membrane based on interfacial polymerization regulation and a preparation method thereof. The method comprises the following steps: preparing a water phase system and an oil phase system, and sequentially injecting the water phase system and the oil phase system into a hollow fiber ultrafiltration membrane; performing interfacial polymerization reaction on the water phase system and the oil phase system on the surface of the hollow fiber ultrafiltration membrane; and drying to obtain the hollow fiber nanofiltration membrane. By adopting the method, the interception performance and flux of the nanofiltration membrane can be effectively adjusted, and the stability and applicability of the nanofiltration membrane are improved. The nanofiltration membrane is low in water contact angle and high in oil contact angle. Particularly, the surface porosity, the effective aperture, the sodium sulfate retention rate, the sodium chloride retention rate, the flux of sodium sulfate, the flux of sodium chloride and other properties of the nanofiltration membrane can be designed and accurately controlled according to requirements, and the properties of the nanofiltration membrane can be accurately designed and customized by adopting the method disclosed by the invention; the performance of the green and natural modified hollow fiber ultrafiltration membrane is realized, and an innovative solution is provided for high-salt resource recovery.

The invention discloses a polyamide acid-resistant nanofiltration membrane and arsenic removal application thereof in hair dye preparation. According to the amide acid-resistant nanofiltration membrane, a polyamine monomer and trimesoyl chloride are subjected to an interface reaction on an ultrafiltration supporting bottom membrane, and the polyamide acid-resistant nanofiltration membrane containing the Telogen structure is obtained. According to the method for removing the arsenic in the hydroxyethyl diphosphoric acid, a polyamide acid-resistant nanofiltration membrane containing a Troger structure is adopted for at least one time of filtration treatment, the concentration of arsenate in the hydroxyethyl diphosphoric acid after secondary filtration treatment is reduced to 4.60 mg / kg from 480.02 mg / kg, and the arsenic content of the hair dye prepared from the hydroxyethyl diphosphoric acid is smaller than 0.07 mg / kg. According to the polyamide acid-resistant nanofiltration membrane containing the Troger structure, which is obtained by adopting a limited preparation method, the acid resistance is greatly improved, the separation selectivity is higher, arsenic in hydroxyethyl diphosphate can be effectively removed, and the arsenic content in a hair dye is greatly reduced.

The invention relates to a seawater desalination reverse osmosis membrane and a preparation method thereof, and relates to the field of seawater desalination treatment.The preparation method comprises the following steps that a supporting membrane is cleaned and dried, and the pretreated supporting membrane is obtained for standby application; immersing the pretreated support membrane into the water phase liquid, taking out the support membrane, and scraping off redundant water phase liquid to obtain a base membrane loaded with a water phase; carrying out contact reaction on the base membrane loaded with the water phase and organic phase liquid to obtain a reacted base membrane; carrying out heat treatment on the reacted base film to obtain a cured base film; and immersing the cured base membrane into the grafting modified monomer solution, taking out the cured base membrane, carrying out ultraviolet curing to obtain a modified membrane, washing the modified membrane, and storing the washed modified membrane in water to obtain the seawater desalination reverse osmosis membrane. The seawater desalination reverse osmosis membrane prepared by the invention has high flux, good desalination effect and anti-pollution performance, has good stability, and can keep good working performance for a long time.

The invention belongs to the technical field of membrane separation, and particularly relates to a preparation method and application of a high-permeability polyamide reverse osmosis membrane. According to the invention, the problems of high energy consumption and poor water production quality caused by non-ideal flux and rejection rate of the current reverse osmosis membrane product are solved, tetrabutylammonium bromide and acyl chloride form ion pairs to reduce hydrophobicity, a hydrogen bond network of urea destroys a hydrophobic barrier of an organic phase, and migration of acyl chloride to a water phase interface is promoted; the eutectic solvent is adsorbed on a water phase interface to form a'catalytic microenvironment ', amido of an amine monomer is attracted to be close to the interface, and the concentration of a reaction area is increased. During reaction, tetrabutylammonium bromide enables an amine monomer to stably attack a transition state of acyl chloride through electrostatic interaction, and reaction activation energy is reduced; urea and sodium hydroxide in a water phase can be jointly used as an acid-binding agent to neutralize generated hydrochloric acid so as to prevent amido protonation inactivation. The method is simple to operate and suitable for large-scale production.

The invention belongs to the field of separation membranes, and particularly relates to an anti-pollution and washable reverse osmosis membrane and a preparation method thereof. The reverse osmosis membrane provided by the invention is prepared according to the following steps: soaking a nascent state polyamide reverse osmosis membrane in a first treatment solution, taking out and cleaning, then soaking in a second treatment solution, taking out and draining to obtain the anti-pollution and washing-resistant reverse osmosis membrane, the nascent state polyamide reverse osmosis membrane comprises a non-woven fabric layer, a porous support layer and a polyamide separation layer which are in contact in sequence; the first treating fluid contains double-end amino polyethylene glycol and triethylamine; the second treatment liquid contains polyvinyl alcohol and alpha-aldehyde group-omega-carboxyl polyethylene glycol. Experimental results show that the reverse osmosis membrane provided by the invention has relatively high anti-pollution capacity, desalting rate and acid and alkali cleaning resistance.

The invention relates to the technical field of water treatment membranes, in particular to a polyamide reverse osmosis membrane with anti-fouling performance and a preparation method of the polyamide reverse osmosis membrane. The polyamide reverse osmosis membrane is prepared by the method. The method comprises the following steps: S1, preparing a first diaphragm; and S2, immersing the first membrane into an amino compound solution for interfacial polymerization reaction, and then cleaning to obtain a second membrane, namely the polyamide reverse osmosis membrane. And S3, coating the second membrane with an alcohol polymer solution, and then carrying out second drying treatment to obtain the polyamide reverse osmosis membrane containing the coating. According to the invention, the polyamide reverse osmosis membrane with remarkable anti-pollution performance on cationic pollutants can be prepared.

The precise molecular sieving architectures with Janus-like characteristics via an interpenetrating polymer network combining the hydrophilic cPI polymer and hydrophobic microporous covalent organic framework (COF) exhibit super-high permeances for both polar and nonpolar solvents. A unidirectional diffusion and convection process significantly speeds up chemically stable COFs with uniform and tailorable channels growing on polymeric hollow fibre that can efficiently separate organic solvents under ultrafiltration conditions.

The invention discloses a high-water-permeability anti-pollution reverse osmosis membrane and a preparation method thereof, and belongs to the technical field of water treatment membranes. The reverse osmosis membrane comprises a porous support layer, a polyamide separation layer and a composite anti-pollution functional layer, and the composite anti-pollution functional layer is composed of a polyvinyl alcohol matrix and a nanoscale water channel material uniformly dispersed in the polyvinyl alcohol matrix. Comprising the steps of coating liquid preparation, base membrane pretreatment, composite functional layer construction, cross-linking and curing, a rapid transmission path is provided for water molecules by introducing a nanoscale water channel material, the water flux of the reverse osmosis membrane is greatly improved on the premise that the excellent pollution resistance of a PVA coating and the high selectivity of the membrane are kept, and the service life of the reverse osmosis membrane is prolonged. The technical problem that the membrane flux is severely reduced due to a traditional PVA coating is solved, and the method has wide application prospects in the fields of seawater desalination, brackish water desalination, ultrapure water preparation, wastewater reuse and the like.

The invention relates to a selective nanofiltration membrane as well as a preparation method and application thereof. The selective nanofiltration membrane comprises a support layer and a separation layer, the separation layer is obtained through interfacial polymerization of an oil-phase reactant and a water-phase reactant; the water-phase reactant comprises a negatively charged monomer and a positively charged monomer; the positively charged monomer comprises any one or a combination of at least two of polyvinylamine, polyethyleneimine, diethylenetriamine, water-soluble chitosan, quaternized polyethyleneimine, polyallylamine or triethylene tetramine. According to the method, monomers with different charges are added into a water phase, so that the nanofiltration membrane is wholly charged and neutral, the interception of sodium sulfate can be effectively reduced, the interception of antibiotics is increased, and the separation of the antibiotics and inorganic salts can be efficiently promoted.

The invention belongs to the field of seawater desalination separation membrane preparation, and particularly relates to a preparation method and application of a seawater desalination reverse osmosis membrane with oxidation resistance. The preparation process of the reverse osmosis membrane for seawater desalination is adjusted, and a micromolecular antioxidant containing a phenolic hydroxyl group and a tert-butyl structure is introduced in a swelling-embedding manner after interfacial polymerization is completed, so that on one hand, the oxidation resistance of the reverse osmosis membrane is improved, and on the other hand, the embedding of the micromolecular antioxidant makes up for the defects of a polyamide layer; the desalination and boron removal capabilities are improved. The antioxidant capacity of the polyamide can be improved under the condition that the desalting capacity of the polyamide is not sacrificed. The seawater desalination reverse osmosis membrane prepared by the method provided by the invention has higher oxidation resistance and better desalination and boron removal capabilities than an original membrane.

The utility model discloses a reverse osmosis membrane shell sealing structure. The reverse osmosis membrane shell sealing structure comprises a membrane shell and an end cover assembly arranged in the inner space of the membrane shell, the end cover assembly comprises an end cover bearing plate, an end cover sealing plate and a U-shaped end cover sealing ring; the end cover bearing plate is connected with the membrane shell, the end cover sealing plate is arranged on one side of the end cover bearing plate and connected with the membrane shell, and the middle of the end cover sealing plate penetrates through the end cover bearing plate; one end of the U-shaped end cover sealing ring is connected with one end of the end cover sealing plate and located on the inner wall of the membrane shell, and a U-shaped opening faces the interior of the membrane shell; the U-shaped end cover sealing ring is tightly attached to the inner wall of the membrane shell and the end cover sealing plate under the action of pressure to form self-pressure sealing. According to the device, the self-pressure sealing function of the U-shaped end cover sealing ring is utilized, so that the sealing effect of the reverse osmosis membrane shell during high-pressure operation is improved; and when the equipment is stopped, the pressure of the internal medium is zero, and the pressure between the U-shaped sealing ring and the end cover sealing plate only comes from the natural tension of the U-shaped sealing ring, so that the U-shaped sealing ring is very easy to disassemble.

The invention belongs to the field of inorganic chemical industry, and particularly relates to a method and a system for efficiently utilizing a phosphate fertilizer byproduct, the method comprises the following steps: carrying out acidolysis on fluosilicic acid with the concentration of more than or equal to 45% wt and concentrated sulfuric acid to generate a mixed solution of silicon tetrafluoride gas and fluorosulfonic acid; the mass ratio of the fluosilicic acid to the concentrated sulfuric acid is controlled to be 1: (4-15); pyrolyzing the obtained fluorosulfonic acid to generate dilute sulphuric acid, hydrogen fluoride and water vapor, forming 98% concentrated sulphuric acid from part of dilute sulphuric acid and fuming sulphuric acid, drying hydrogen fluoride to obtain crude hydrogen fluoride gas, and condensing and rectifying to obtain anhydrous hydrogen fluoride; the rest dilute sulphuric acid is partially compounded and then returned for acidolysis, and the rest dilute sulphuric acid is used for producing white carbon black and flows back to a wet-process phosphoric acid system; and circularly absorbing the obtained silicon tetrafluoride gas by using secondary concentrated fluosilicic acid to obtain fluosilicic acid with the mass concentration of more than or equal to 45%, recycling the fluosilicic acid for acidolysis reaction, and modifying the concentrated by-product silicon dioxide to obtain the high-activity white carbon black. The problems of energy consumption and cost are solved, and efficient circulation and poly-generation of fluorine and silicon resources are achieved in the whole process.

The invention relates to a high-effect reverse osmosis membrane as well as a preparation process and application thereof, and belongs to the technical field of water treatment. The preparation method comprises the following steps: soaking a base membrane in a water-phase solution, taking out the base membrane, drying the surface of the base membrane, coating the base membrane with an oil-phase solution for interfacial polymerization reaction, and curing to obtain the reverse osmosis membrane; and coating the surface of the reverse osmosis membrane with the modified liquid, and drying to obtain the high-efficiency reverse osmosis membrane. Wherein the formula of the modified liquid comprises the following components in parts by weight: 3 to 5 parts of polyvinyl alcohol, 1 to 3 parts of polyacrylic acid, 0.3 to 0.5 part of citric acid, 0.1 to 0.3 part of cocamidopropyl hydroxysulfobetaine, 0.05 to 0.1 part of modified carbon nitride quantum dot dispersion liquid and 60 to 80 parts of deionized water. The reverse osmosis membrane prepared by the invention has excellent water flux, salt rejection rate and stain-resistant and self-cleaning functions.

Provided are methods of extracting lithium from a lithium containing solution, as well as the resulting compositions. The method includes supplying a lithium containing solution to a lithium capture step, the lithium capture step being operable to capture lithium from the lithium salt containing solution. The method further includes recovering lithium from the lithium capture step to produce a lithium rich stream. In especially preferred methods, the lithium capture step is performed to increase the lithium to sodium ratio above at least 1:1. Optionally, the lithium rich stream can be purified to remove divalent ions and borate ions. The lithium rich stream is then concentrated by supplying the lithium rich stream to a reverse osmosis step to produce a concentrated lithium rich stream.

A water treatment plant or system for the production of permeate includes a reverse osmosis stage and a permeate stage. The reverse osmosis stage can include a piping system having a supply line for process input water, a reverse osmosis pump, and a reverse osmosis tank. The reverse osmosis tank has an inlet for process input water coming from the reverse osmosis pump, a membrane, and an outlet for permeate. The permeate stage, which can have a line system forming a circuit, can include a permeate tank, a permeate pump, and a tapping point for connecting at least one consumer or user of permeate. The reverse osmosis stage and the permeate stage can be connected to one another via a connecting line in such a way that the reverse osmosis stage feeds the permeate stage with permeate. The circuit of the permeate stage can include a sterile filter.

The invention relates to the technical field of deodorants, and discloses a preparation method and application of an onion extract high-efficiency low-temperature concentrated deodorant, and the preparation method comprises the following steps: S1, dicing onions, soaking in a color protection solution, and draining for later use; s2, putting the diced onions into a supercritical extraction kettle, and extracting by taking ethanol as an entrainer; s3, a mixed system in the extraction kettle is sequentially guided into a first-stage separation kettle and a second-stage separation kettle through a throttling valve; s4, filtering the onion extract crude product through a bifunctional biomimetic membrane, and performing nanofiltration through a nanofiltration system; s5, concentrating the nanofiltration membrane trapped fluid in vacuum low-temperature concentration equipment to obtain an onion extract concentrated solution; s6, preparing microcapsule powder from the onion extract concentrated solution, a solvent, an emulsifier, deionized water and modified beta-cyclodextrin; mixing the microcapsule powder with menthol to prepare a solid deodorant; or compounding with ethanol to prepare liquid spray.

The technology includes a method for removing sulfur dioxide (SO2) from a gas stream, where SO2 gas is contacted by a diluted sulfuric acid (H2SO4) stream and absorption takes place in a quench tower. The dissolved SO2 reacts with the excess of oxygen in the gas stream, where the oxidation results in the formation of sulfurous acid (H2SO3) and dilute H2SO4. For the complete oxidation of the dissolved SO2, an electrolyzer and / or liquid injectants are used. This results in the formation of diluted H2SO4. The diluted H2SO4 is processed in an enrichment unit to produce concentrated H2SO4 and fresh water. A portion of the diluted H2SO4 and / or fresh water is recycled back to the quench tower for the continued acidic absorption of the incoming SO2 in the gas stream, thereby not relying on an external water source.

The invention discloses an organic solvent-resistant nanofiltration membrane and a preparation method thereof, and belongs to the technical field of nanofiltration membranes. The preparation method comprises the following steps: performing plasma treatment on a PE (Poly Ethylene) porous base membrane, vacuumizing, introducing inert gas for plasma activation, introducing amino-containing precursor gas for amination, and performing vacuum impurity removal and normal-pressure inflation to obtain an aminated base membrane; and immersing into a water-phase solution containing a water-phase monomer and an imidazole monomer, taking out, removing redundant solution, covering the plasma treatment surface with an organic-phase solution, carrying out interfacial polymerization to form a polyamide composite desalination layer containing an imidazole structure, and drying to obtain a finished product. The desalination layer in the prepared nanofiltration membrane is connected with the base membrane through a C-N covalent bond, the retention rate of MgSO4 is greater than or equal to 99.16% and the permeability of DMF is greater than or equal to 93.54% for a 10g / L DMF and 2000ppm MgSO4 system under the conditions of 1MPa and 25 DEG C, and the performance is stable after the DMF is soaked for 30 days.

The application discloses a high-precision intelligent control and adjustment method for stachydrine fermentation and purification, and relates to the field of biological fermentation process control. The method comprises the following steps: obtaining a stachydrine mixed solution in a first sugar content interval; inoculating Eurotium cristatum at a first preset temperature after sterilization to start fermentation and obtain an initial fermentation liquor; monitoring the content ratio change of stachydrine and non-target sugars in real time through HPLC to obtain sugar content monitoring data; introducing a membrane separation device for selective dialysis to obtain membrane permeation rate monitoring data; performing dynamic evaluation on stachydrine enrichment according to the sugar content monitoring data and the membrane permeation rate monitoring data, generating a dynamic adjustment strategy for fermentation conditions based on the evaluation results; and performing fermentation process adjustment control. The method solves the technical problem that the existing stachydrine fermentation and purification cannot realize real-time and accurate monitoring and dynamic adjustment of fermentation conditions, resulting in low fermentation efficiency and low purity, and achieves the technical effect of improving the fermentation efficiency and purity of stachydrine through intelligent control of the fermentation process.