59 results about "Cross-flow filtration" patented technology

The invention relates to the technical field, and discloses a product dehydration optimization method based on an inclined box dense grader and an HNS ultrafilter, which comprises the following steps: introducing slurry into a vibration inclined box dense grader through a feed distribution system, and dynamically adjusting the vibration frequency, amplitude and period by combining an intermittent vibration system and a slurry concentration detection control system, the concentration self-adaptive control is realized; overflowing slurry is conveyed into an HNS ultrafilter through a slurry conveying system, and efficient separation is achieved through a centrifugal force field and cross flow filtration; the filtrate is shunted by a clear water self-circulation system and is used for process recycling and equipment cleaning; and the concentrated discharged slurry of the HNS ultrafilter and the underflow of the thickener are mixed and output or return to the previous process. The general drawing arrangement is optimized, the slurry dehydration efficiency is improved, and valuable metal is recycled to the maximum extent.

The utility model relates to a beer filtering device applying a cross-flow filtering technology, which comprises a base, a stock solution tank is fixedly mounted at the top of the base, a storage tank is fixedly mounted at the top of the base, and a filtering mechanism is arranged at the top of the base. According to the beer filtering device applying the cross-flow filtering technology, when beer needs to be filtered, firstly, a controller drives a booster pump outside a first water inlet pipe to be started, at the moment, the beer liquid enters a first filtering tank through the first water inlet pipe, and at the moment, a first filtering membrane group can roughly filter the beer through a porous supporting layer, a transition layer and a separation layer; at the moment, part of the fermented beer liquid flows through the upper end of the first filtering membrane group under the action of flow shearing force, the electromagnetic valve is started, enters the return pipe from the first shunt pipe and returns to the stock solution tank through the return pipe, the rest of the beer liquid enters the second filtering tank through the second water inlet pipe, and the secondarily filtered beer liquid enters the storage tank through the guide pipe, so that filtering is completed.

This product relates to the field of eyewash production technology, providing a filter for eyewash production, including a raw material tank for storing the eyewash concentrate, a coarse filter for filtering large particulate impurities, and a cross-flow filter including a filter tube and a filter membrane. One end of the filter tube is connected to the coarse filter, and the other end passes through the cross-flow filter and connects to the raw material tank. An opening is provided at the bottom of the filter tube located inside the cross-flow filter. The filter membrane is positioned on the opening and parallel to the flow direction of the eyewash through the filter tube, used to filter large molecular impurities in the eyewash. This filter removes large molecules through the opening parallel to the flow direction of the eyewash and the filter membrane, and washes away any remaining large molecules on the filter membrane surface through the flow of the eyewash, preventing large molecules from clogging the filter membrane and improving the utilization rate of the filter membrane.

The invention discloses a device for automatically concentrating bacteria in a water environment, and belongs to the technical field of microbiological detection and enrichment equipment. By arranging a combined structure of the sediment filtering module and the cross-flow enrichment module, large-particle impurities can be removed on the premise that downstream analysis is not affected, meanwhile, bacteria are accurately intercepted, and the overall enrichment efficiency is improved; a cross-flow filtering structure effectively alleviates the problem of filter membrane blockage, and stable enrichment can be carried out on a water sample from several liters to dozens of liters under field or laboratory conditions in cooperation with a circulating design and a high-flux water pump; the automation degree is high, operation is easy and convenient, and on-site enrichment can be achieved; a relay is adopted to control each functional module, and a control system based on an RS-485 bus is combined, so that the functions of multi-segment program control, automatic start and stop, remote monitoring and the like are supported, the manual intervention requirement is reduced, and the operation stability is improved. The system is combined with field communication equipment, can construct a multi-point sampling and centralized control microorganism sampling network, and is suitable for monitoring different water bodies such as rivers, lakes, reservoirs and the like.

This utility model discloses an inlet baffle ring and a cross-flow filter assembly for a multi-channel internal filtration columnar cross-flow filter element, solving the technical problem of easy clogging at the inlet end of the multi-channel internal filtration columnar cross-flow filter element. It includes a baffle ring body, which is detachably installed in the inlet channel before the inlet end of the multi-channel internal filtration columnar cross-flow filter element during use. The baffle ring body is densely covered with inlet through holes, which are used to guide the liquid to be filtered, flowing from the inlet channel to the inlet end of the multi-channel internal filtration columnar cross-flow filter element, into the inlet end of the multi-channel internal filtration columnar cross-flow filter element. The inlet baffle ring of the multi-channel internal filtration columnar cross-flow filter element ensures that the liquid to be filtered passes through the inlet through holes before entering the multi-channel internal filtration columnar cross-flow filter element, preventing large particles of impurities from directly contacting and clogging the inlet end of the multi-channel internal filtration columnar cross-flow filter element.

The invention discloses a gas-liquid-solid three-phase airlift external loop reactor integrated with a cross-flow filtering device and application of the gas-liquid-solid three-phase airlift external loop reactor in dimethyl carbonate synthesis. The core of the invention lies in that a high-temperature-resistant special ceramic membrane cross-flow separator is directly integrated in an outer circulation downcomer of the reactor, so that a liquid-phase product generated by reaction can be efficiently, continuously and stably separated from a micron-sized solid catalyst on line; and the catalyst is efficiently intercepted and directly returns to the reaction zone to form a closed-loop cycle. The process defects that a traditional metal filter is easy to block, needs frequent maintenance and depends on a high-energy-consumption flash evaporation separation catalyst are overcome. Compared with a traditional reactor and a separation process, the device can stably maintain the concentration and activity of the catalyst in the reaction zone, has the remarkable advantages of low energy consumption, high separation efficiency, compact structure and continuous operation, and has a wide industrial application prospect.

The invention discloses a fermentation-membrane separation coupling production method of high-purity lysine, and belongs to the technical field of amino acids, the method comprises the following steps: fermentation: inoculating a corynebacterium glutamicum seed culture solution in a lysine fermentation culture medium, carrying out fermentation culture at 32-34 DEG C for 28-30 hours, and when the fermentation culture is carried out for 17-19 hours, carrying out membrane separation on the fermentation culture medium to obtain the high-purity lysine. N-(4-aminobutyl) acetamide is added; performing membrane separation: performing cross-flow filtration on the fermentation liquor by adopting a surface modified membrane, controlling the inlet pressure to be 0.4-0.5 MPa, the outlet pressure to be 0.2-0.3 MPa and the temperature to be 30-35 DEG C, and obtaining a lysine crude product after the membrane separation is finished; post-treatment: carrying out ion exchange and crystallization on the lysine crude product to obtain a high-purity lysine product; the release of viscous pollutants is reduced from a fermentation source, the pollution resistance of the membrane is improved, the flux recovery rate of the membrane is improved, and efficient coupling of fermentation and separation is realized.

The invention relates to the field of methanol synthesis catalysts, and particularly discloses a high-purity low-sodium methanol synthesis catalyst and a preparation method thereof. The preparation method of the high-purity low-sodium methanol synthesis catalyst comprises the following steps: mixing aluminum nitrate and sodium hydroxide for reaction to obtain pseudo-boehmite colloid; carrying out cross-flow filtration on the pseudo-boehmite colloid by adopting an ultrafiltration membrane under an ultrasonic condition, and carrying out backwashing to obtain sodium-removed alumina gel; mixing sodium carbonate with the copper-zinc mixed solution for co-precipitation, and washing the precipitate to obtain a binary precursor; and mixing the sodium-removed alumina gel with the binary precursor, pulping, aging, washing to further remove sodium, filtering, and drying, granulating, calcining and forming a filter cake to obtain the high-purity low-sodium methanol catalyst. The preparation method of the high-purity low-sodium methanol catalyst has the advantages that the content of impurity sodium can be reduced, and the catalytic activity and selectivity of the methanol synthesis catalyst are improved.

The utility model relates to the field of wine cross flow, in particular to a wine cross flow filter. The filter comprises a filter cartridge, and a filter frame is arranged in the filter cartridge. The cross-flow filter element is carried by the filter frame in the filter cartridge, so that impurities in wine can be effectively filtered; a second gear in the cleaning mechanism drives a filter frame and a cross-flow filter element to synchronously rotate, so that a cleaning brush can timely remove blockages on the surfaces of the filter frame and the filter element, the influence of impurity accumulation on the filter efficiency is avoided, continuous and smooth filtration of wine is ensured, and the product purity is improved; moreover, when the filter frame and the filter element rotate, a flushing system composed of a water injection pipe, a flow dividing column and a spray head can conduct water flow flushing on the filter frame and the filter element, fine particles and viscous substances in filter hole channels and gaps are deeply cleaned, double cleaning of mechanical friction and fluid flushing is achieved in cooperation with a cleaning brush, the cleanliness is improved, and the risk of secondary pollution is reduced.

The application provides a method and a system device for continuous salt removal in a triacetone amine rectification process, and the method comprises the following steps: performing solid-liquid separation treatment on a salt-containing organic liquid obtained in the rectification, and the solid-liquid separation treatment is sedimentation treatment; performing cross-flow filtration treatment on a liquid phase obtained in the solid-liquid separation to obtain a permeate and a concentrated liquid, and the permeate is the salt-removed organic liquid. The method and the system device can ensure the continuity and intensiveness of the rectification process, shorten the high-temperature residence time of the material, reduce the energy consumption, and at the same time, maximize the reduction of high-temperature polymerization of the material, and improve the yield.

The invention relates to the technical field of electronic industrial wastewater, and discloses a grinding wastewater reuse treatment system, which comprises a wastewater collection module, a disc type filtration module, a ceramic membrane filtration module, an RO treatment module, a produced water reuse module and an automatic control module. The water quality and water quantity homogenization adjustment is performed on the grinding wastewater through the wastewater collection module; suspended solids are mechanically intercepted through a disc type filtering module by adopting a filtering disc with a groove; the ceramic membrane filtration module is used for performing cross-flow filtration to separate colloid and pollutants; residual particles are reduced through a security filter of the RO treatment module; and finally, the produced water is stored and conveyed to a pure water system by the produced water recycling module, so that wastewater recycling is realized. And the automatic control module realizes full-automatic chain operation through the PLC unit and the instrument monitoring unit. According to the invention, the wastewater recycling rate and the system reliability are improved, and the requirements and operation and maintenance of the semiconductor industry on water resource recycling are met.

The embodiment of the invention discloses a muddy water treatment system and a muddy water treatment method. The muddy water treatment system comprises a sedimentation tank, a potential mixer, a water pump, a first dosing unit and an ultrafiltration unit, the settling pond is used for settling suspended matters in water; the potential mixer is communicated with the sedimentation tank and is used for mixing fluid and total solids in the potential mixer; the water pump is used for conveying clear liquid containing particles and colloids in the sedimentation tank into the potential mixer; the first dosing unit is communicated with the potential mixer, and the first dosing unit is used for adding cationic polyelectrolyte into the potential mixer; the ultrafiltration unit is communicated with the potential mixer and comprises a hollow fiber ultrafiltration membrane, and the hollow fiber ultrafiltration membrane is used for performing cross-flow filtration on liquid entering the ultrafiltration unit. According to the muddy water treatment system and the muddy water treatment method disclosed by the embodiment of the invention, fine particles and colloidal substances can be effectively prevented from being blocked or adsorbed in membrane holes and inlets, so that membrane pollution is relieved fundamentally.

The application provides a crude oil demetallization method and relates to the technical field of petroleum refining processing. The method avoids the disadvantages of the traditional demetallization method of an electric desalting device, selects the ultrasonic technology to strengthen the crude oil demetallization process before the crude oil enters the electric desalting device, removes the chelate precipitate by using the cross-flow filtration technology and the phase separation technology, improves the utilization rate of the demetallization agent, controls the residence time of the demetallization reaction by using a permeation side control valve, makes the oil agent mixture circulate in the system, realizes the efficient removal of the metal in the crude oil, and constructs a continuous online recyclable demetallization process technology.

The application provides a terephthalic acid bis-hydroxyethyl ester crude product purification method and device and a terephthalic acid bis-hydroxyethyl ester preparation method. The method comprises the following steps: allowing a first mixed solution containing terephthalic acid bis-hydroxyethyl ester crude product to enter a first adsorption unit, performing first adsorption treatment in the presence of a first adsorbent, and obtaining a second mixed solution; allowing at least part of the second mixed solution to enter a cross-flow filtration unit, performing cross-flow filtration through a cross-flow membrane, and obtaining a first filtrate containing terephthalic acid bis-hydroxyethyl ester and a first slurry containing activated carbon; allowing the first filtrate to enter a second adsorption unit, performing second adsorption treatment in the presence of a second adsorbent, and obtaining a purified solution; and allowing the purified solution to enter a crystallization unit to perform crystallization treatment, and obtaining purified terephthalic acid bis-hydroxyethyl ester. The method can avoid filter membrane pollution and blockage, avoid single adsorption effect, maintain stable adsorption efficiency, and realize recycling and recovery of the adsorbent.

The utility model discloses an external circulating treatment device for cross-flow filtration. The external circulating treatment device comprises a reaction kettle, an external filtering assembly and a stirring assembly, the external filtering assembly comprises a cross-flow filter, a circulating feeding pipe, a circulating discharging pipe, a filtrate collecting pipe and a circulating pump; the cross-flow filter is provided with a filtering channel and a filtrate collecting cavity, the two ends of the filtering channel are communicated with the reaction kettle treatment cavity through a circulating feeding pipe and a circulating discharging pipe respectively, a filtrate collecting pipe is communicated with the filtrate collecting cavity, and the circulating pump is arranged on the circulating discharging pipe. The stirring assembly comprises a motor, a stirring shaft, a stirring piece and a rotating joint; the motor is in driving connection with the stirring shaft; the rotary joint is mounted on the stirring shaft and is provided with an air inlet; an air outlet is formed in the outer wall of the stirring shaft, an air guide channel is formed in the stirring shaft and communicated with the air inlet and the air outlet, and the stirring piece is fixedly connected to the stirring shaft. The device can realize continuous treatment of stirring and filtering processes, improves product quality and treatment efficiency, and realizes recycling of solid materials.

This invention relates to the field of oil-water separation technology, and provides a method and system for treating industrial oily wastewater based on dynamic membrane separation. The method includes: performing demulsification and oil removal operations on solids-free wastewater to obtain primary wastewater and demulsifier usage records, and acquiring oil droplet particle size distribution; obtaining the maximum particle size of a preset minimum percentage of oil droplets from the oil droplet particle size distribution to obtain a first particle size, and acquiring a target safety factor; performing a weighted calculation on the first particle size and the target safety factor to obtain the target pore size of the dynamic membrane; querying the type of pre-coating agent corresponding to the target pore size of the dynamic membrane to obtain a desired type; identifying the application instruction sequence based on the desired type and the target pore size of the dynamic membrane; performing a surface modification operation on a cross-flow filter ceramic substrate membrane using the target pre-coating agent according to the application instruction sequence to obtain a target dynamic membrane; and performing oil-water separation. This invention can improve the separation efficiency of oil-water separation in wastewater.

An operation method of a hollow fiber membrane module is described, the operation method including: a filtration step of performing cross-flow filtration by supplying a feed to an outer surface side of a hollow fiber membrane, in which in the filtration step, a ratio of a viscosity μf of the feed to a viscosity μp of a filtrate satisfies a relation of μf / μp≥1.5, and a flow rate ratio of a flow rate vp of the filtrate to a flow rate vf of the feed satisfies a relation of 0.02≤vp / vf≤0.3.

The application discloses a kind of wastewater treatment processes for p-aminophenol production, belong to p-aminophenol wastewater treatment technical field.First by graphene, anion exchange resin and hyperbranched polyether amine as raw material, prepared adsorption material, to wastewater is first step processing, reduce the content of TOC and metal ion, then through Fenton process second step processing, make hydrogen peroxide and ferrous ion reaction produce strong oxidizing hydroxyl radical, to attack difficult degradation organic matter chemical bond, and reduce COD in wastewater, reduce the harm to environment, finally into ceramic membrane filtration, ceramic membrane has good performance in wastewater treatment, by cross-flow filtration mode, can long-term stable in wastewater separation pollutant, complete p-aminophenol production wastewater treatment process.

Self-cleaning filter cartridges comprising an inlet for receiving a fluid and an outlet for discharging contaminants removed from the fluid. The filter cartridge comprising a filter media and a helical structure located within the filter media. The helical structure comprising a first opening and a second opening, at least one rib having an open core and configured as a continuous spiral from the first opening to the second opening with a decreasing radius and at least one scraping element protruding from the at least one rib and configured to contact the filter media. The helical structure is configured to rotate inside the filter media and dislodge contaminants attached to the interior surface of the filter media. A machine, such as a machining containing the self-cleaning filter cartridges, and methods of cleaning fluids using the filter cartridges are also disclosed.

Belonging to the technical field of high purity chemical preparation, the invention provides an electronic grade caustic soda purification production process, which comprises the following steps: S1, preheating a solar photovoltaic NaOH solution to 55 + / -2 DEG C, and then carrying out precision filtration through a titanium sintered felt dynamic cross-flow filter; s2, regulating the temperature of the filtered NaOH solution to 45 + / -2 DEG C, and sequentially carrying out adsorption purification through a strong acid resin column and phosphoramidate chelate resin; s3, heating the purified NaOH solution to 45 + / -1 DEG C, removing residual particles through a polytetrafluoroethylene folded filter element filter, preheating to 60 + / -1 DEG C, and concentrating in a falling film vacuum concentrator; and S4, quickly cooling the concentrated solution to 35 DEG C through a titanium corrugated pipe cooler, and then filling nitrogen for sealed storage. According to the process, the solar photovoltaic NaOH solution can be purified into the electronic-grade caustic soda through the working procedures of dynamic cross-flow filtration, resin enhanced adsorption, precise filtration, vacuum concentration and the like, the concentration reaches 47.0 + / -0.5%, and the ultra-pure reagent requirements of the electronic industry such as semiconductors and display panels are met.

The invention relates to the technical field of cubilose peptide production, and discloses an automatic continuous cubilose peptide production system. A raw material pretreatment unit of the system performs graded cleaning and multi-stage filtering on cubilose raw materials and outputs clean raw materials; the enzymolysis reaction unit adopts a dynamic temperature control technology, and is matched with compound protease for staged enzymolysis according to the characteristics of raw materials; the membrane separation and purification unit screens a target peptide fragment through cross-flow filtration; the concentrating and drying unit performs low-temperature vacuum concentration on the product and then performs spray drying to obtain a powder finished product; the quality monitoring unit collects data in real time and generates a parameter curve, and alarms when abnormity occurs; the central control unit receives data and regulates and controls parameters of all the units, and closed-loop control over the production process is achieved. The system realizes the automatic continuous production of the cubilose peptide, and improves the production efficiency and the product quality. According to the invention, the interference of impurities on the reaction process is avoided, so that the high quality of the final product is ensured.

A fluid filtration system comprising a cross-flow filter is arranged to permit a first pump to recirculate part of the retentate of the filter to the inlet of the cross-flow filter and a second pump to return part of the permeate to the inlet of the cross-flow filter. A third pump is configured supply source fluid to the inlet of the filter. The flow path between the second pump and the cross-flow filter inlet may include an adsorption filter that may selectively remove contaminants, toxins, or pathogens in the permeate. A controller may control the first, second and third pumps to provide predetermined flow ratios among the fluid flow paths of the system in order to achieve a desired filtration level. This system may be applicable to the removal of harmful substances from blood, by first separating the plasma from the blood and then removing harmful substances from the plasma.

The invention discloses a membrane coupling type microalgae reactor in the field of sewage treatment, and the membrane coupling type microalgae reactor comprises a water supply assembly used for supplying to-be-treated sewage; the first reactor is communicated with the water outlet of the water supply assembly, the first reactor comprises a rotatable biological membrane structure and an aeration structure, and the sewage is primarily treated through a biological membrane; the second reactor is communicated with the first reactor; the ceramic membrane separation unit is communicated with the second reactor and is used for carrying out cross-flow filtration on sewage discharged from the second reactor so as to realize collection of a biological membrane and microalgae and conveying the biological membrane back into the first reactor; the invention further discloses a sewage treatment method. The sewage treatment device has the beneficial effects that microalgae growth and biomass accumulation can be enhanced through two-stage mixed culture of the first reaction cylinder body and the second reaction cylinder body, illumination of the biological modified filler is more uniform, the sewage treatment performance is improved, and the device is lower in energy consumption.

The silicon carbide cutting fluid filtering device disclosed in the application comprises a liquid inlet mechanism, a filtering mechanism and a backwashing mechanism, the filtering mechanism comprises a plurality of silicon carbide column membranes, the filtering mechanism can perform cyclic cross-flow filtration on raw water through the silicon carbide column membranes, the raw water is subjected to cross-flow filtration to obtain filtrate and concentrated water after entering the filtering mechanism from the liquid inlet mechanism, the filtrate flows into the backwashing mechanism and is stored in the backwashing mechanism, the concentrated water is discharged outside the filtering mechanism, and the backwashing mechanism can perform backwashing on the filtering mechanism by using part of the filtrate. The application can improve the filtering efficiency, easily maintain a high filtering flux, and still has good filtering performance after long-term use.

The present application relates to the technical field of bacillus subtilis secretion preparation, and discloses a preparation method of a composition containing bacillus subtilis secretion, comprising: physically splitting a sampling flow through a cross-flow filtration module in a sampling period to obtain a first test branch fluid and a second test branch fluid; injecting a fluorescence resonance energy transfer probe into each branch fluid to obtain an enzymatic kinetic signal, determining a kinetic parameter of each branch and calculating a ratio value, providing a preparation trigger instruction based on the ratio value evolution trend, and adding a stabilizer or extracting the composition according to the instruction. The present application uses in-situ two-phase kinetic ratio test logic to decouple the relative distribution of free state activity and attached state activity, offsets background fluorescence noise and sampling fluctuation, solves the determination contradiction between the physical release amount of the secretion and the protein self-degradation effect, and establishes a robustness scale of the composition preparation timing.

The invention belongs to the technical field of ocean wastewater treatment and resource recovery, and particularly discloses an integrated membrane treatment device and method for oil removal and lithium extraction of ocean platform production water.The device body comprises a first-stage oil removal unit and a second-stage lithium extraction unit which are sequentially connected, the first-stage oil removal unit adopts a hydrophilic modified ultrafiltration membrane or microfiltration membrane, and the second-stage lithium extraction unit adopts a hydrophilic modified ultrafiltration membrane or microfiltration membrane; the oil content of inlet water is reduced to below 10mg / L through cross-flow filtration; the secondary lithium extraction unit adopts a composite adsorption film loaded with a lithium ion sieve, selective lithium extraction is carried out on deoiled water, meanwhile, the device is integrated with a monitoring control system and a cleaning regeneration system, and a modular skid-mounted design is adopted. Through cooperation of two stages of functional membranes, deep oil removal and efficient lithium extraction are synchronously completed in a single compact system, the problems that an adsorption method is poor in oil stain resistance and process equipment is dispersed are solved, and the device has the advantages of being high in anti-pollution capacity, high in resource recovery rate, high in automation degree and suitable for offshore platform space limitation.

The invention belongs to the technical field of amino acid separation, and particularly discloses a method for recovering alanine from a high-salt alanine-containing aqueous solution. The pH value of the solution is adjusted to be close to the isoelectric point (5.0-7.0) of alanine, a polyamide nanofiltration membrane with the molecular weight cut-off of 150-300 Da is adopted for cross-flow filtration, and selective separation of alanine (the cut-off rate is larger than or equal to 85%) and sodium chloride (the cut-off rate is smaller than or equal to 40%) is achieved under the operation pressure of 0.5-4.0 MPa. Concentrating the trapped fluid until the concentration of the alanine is greater than or equal to 15%, and then adding a seed crystal at an isoelectric point for gradient crystallization to obtain the high-purity alanine. The preferable scheme comprises microfiltration pretreatment, two-stage nanofiltration series connection (the first stage is 1.0-2.5 MPa desalination and the second stage is 3.0-4.0 MPa concentration) and a seed crystal induced crystallization process. The method is suitable for fermentation waste liquid or pharmaceutical wastewater containing more than or equal to 6wt% of NaCl and 0.1-2wt% of alanine, the recovery rate is more than 90%, the energy consumption is less than 0.5 kWh / m, and no chemical addition is needed in the whole process.

This invention discloses a membrane coupling-based system and method for treating copper complex wastewater. The method includes: S1 pre-oxidation and complex-breaking treatment; S2 adding a heavy collector to the wastewater and performing cross-flow filtration using a membrane separation device equipped with an electrochemically activated membrane module to obtain a concentrated solution of the heavy collector-copper complex; S3 adjusting the pH of the concentrated solution and performing secondary filtration using the same membrane separation device, retaining the heavy collector for reuse, with the permeate being an acidic solution containing free copper ions; S4 chemically depositing and separating the acidic copper-containing solution to recover copper. In the S2 enrichment stage, a reducing electric field is applied using the membrane as the cathode, and in the backwashing stage, an oxidizing electric field is applied as the anode. The heavy collector is a graft copolymer or terpolymer of polyacrylic acid and β-cyclodextrin, which forms a loose, porous gel layer on the membrane surface during enrichment and naturally peels off. This invention achieves efficient complex breaking of copper complexes, high-purity recovery of copper resources, recycling of the heavy collector, and effective control of membrane fouling.

The printing device (1) includes a conveying member (31) capable of conveying a printing medium (M), an ink unit (421) that applies a pigment-containing ink to the printing medium (M) on the conveying member (31), a treatment liquid unit (422) that applies a treatment liquid containing a component that can aggregate the pigment to form an aggregate (A) to the printing medium (M) on the conveying member (31), a liquid tank unit (5) having a transfer member (52) that sends the aggregate (A) present on the conveying member (31) to a liquid tank (51), a settling tank (6) that accumulates the liquid transferred from the liquid tank (51), and a membrane module (7) that performs cross-flow filtration using a membrane (72) on the liquid introduced from the settling tank (6) into a container (71).