CN102160967B

CN102160967B - Lining-reinforced hollow fiber membrane tube as well as preparation device and preparation method thereof

Info

Publication number: CN102160967B
Application number: CN201110067990.7A
Authority: CN
Inventors: 汪朝晖; 汪效祖; 殷俊霞
Original assignee: Nanjing Tech University
Current assignee: Nanjing Jiuying Membrane Technologies Co ltd
Priority date: 2011-03-21
Filing date: 2011-03-21
Publication date: 2013-06-26
Anticipated expiration: 2031-03-21
Also published as: CN102160967A

Abstract

The invention relates to a lining-reinforced hollow fiber membrane tube as well as a preparation device and preparation method thereof, belonging to the field of preparation of polymer hollow fiber microporous membranes. In the membrane tube, a film forming chimney is designed reasonably, a coating layer on a braided tube led from a coating machine is subjected to controllable steam diffusion-induced phase inversion firstly, and then enters a coagulating bath, so that an open-pore surface skin layer with high porosity is formed on a film separation layer, and the radial direction of the membrane layer is in an integral asymmetric and interpenetrating cell-shaped structure; a composite material is selected to prepare a transition layer, so that the transition layer has excellent adhesive force and hardness, excellent compatibility with a surface separation layer and tiny cubical contraction in a phase conversion process at the same time; optimized braided tube size and braiding density are selected to ensure that the braided tube has lower flexibility; and a method capable of maintaining reasonable roundness and the like in the production process ensures that the lining polyvinylidene fluoride (PVDF) hollow ultrafiltration membrane tube has the advantages of integral asymmetric structure with high integrity, high-porosity surface separation layer, higher back pressure enduring capability and the like.

Description

Lining-reinforced hollow fiber membrane tube and preparation facilities thereof and preparation method

Technical field

The invention belongs to polymeric hollow fiber microporous barrier preparation field, relate to a kind of lining-reinforced hollow fiber membrane tube and preparation facilities thereof and preparation method.

Background technology

Along with the continuous lifting of industrialization degree and going from bad to worse of all kinds of water sources quality, chemical stability is good, mechanical strength is high, contamination resistance becomes by force the more and more general requirement of separation membrane performance.Simultaneously, because the degree of depth of a large amount of water bodys is polluted the water quality type lack of water that causes, make the MBR process become the wastewater processing technology that market prospects are arranged most.Since building up from the exemplary engineering of first MBR of nineteen ninety, MBR process dedicated film element is from flat hollow form or the multichannel external form of expanding to.Current hollow form membrane component has occupied than clear superiority in the MBR in whole world engineering is used, especially lining-reinforced hollow membrane element, although the shortcoming that exists the film separating layer to peel off from enhancement layer the fracture of wire situation can occur hardly, thereby market application foreground is good.The inside bearing strip hollow membrane element of developing for the desired high mechanical properties of MBR process mainly is comprised of the surperficial separating layer of coating and braided tube or other type backing material, undertakes respectively and separates and two functions of high strength.

The film forming mechanism of surface separating layer is consistent with immersion phase inversion masking technique, selectable membrane material is also basically identical, comprises that therefore the membrane material commonly used such as polyacrylonitrile (PAN), polyether sulfone (PES) or Kynoar (PVDF) all is used to prepare the lining-reinforced membrane component.United States Patent (USP) 4,061,821 disclose a kind of method for preparing the PAN hollow-fibre membrane of liner braided tube, U.S. KOCH company

The MBR membrane component is take PES as surperficial separating layer material (Judd S.2006, The MBR BOOK), United States Patent (USP) 5,472, and 607 disclose a kind of PVDF solution coating tubular braid to form the method for the hollow-fibre membrane of being strengthened by braid.Thereafter, patent US7,306,105, the equal polymer raw material take PVDF as surperficial separating layer of CN 1829597A, CN 1864828A, CN1281299C, the disclosed enhancement type hollow fiber film elements such as CN 101239281A, CN 101254420A.Although PAN, PES and PVDF have comparatively ideal chemical stability, and aspect anti-oxidant and antioxidant, PAN and polysulfones series material all are weaker than PVDF.The PVDF resin has the characteristic of fluororesin and resins for universal use concurrently, has good high temperature resistant and resistance to chemical corrosion; It is 1～12 even wider that the pH scope that can bear reaches, and is the most outstanding membrane material of oxidation resistance, can stand harsh oxidant cleaning condition, anti-biodegradation and x radiation x.In engineering of water treatment, clorox is generally used for membrane component as the free chlorine source and cleans and former water sterilization.Therefore the membrane component of PVDF material becomes the first-selected core parts of these engineering of water treatment.

The material of surface separating layer has determined the chemical stability of enhancement mode membrane component, and flux and separation factor depend on the microstructure of separating layer.United States Patent (USP) 5,472, thus the surperficial percent opening of 607 disclosed lining-reinforced PVDF hollow fiber ultrafiltration membrane is low and the overlay section has macrovoid and causes filtration flux on the low side.In its follow-up patent, US5 with the casting solution of the method formation blend of poly-(the acetic acid hexenyl ester) that add partial hydrolysis and alpha-alumina particle, compares with the milipore filter that does not contain alpha-alumina particle in 914,039, shows higher water permeability.Yet this class casting solution often physico-chemical property is unstable and be difficult to make, thereby causes relatively poor repeatability.US5, the hydrophilic component poly-(acetic acid hexenyl ester) that the casting solution in 472,607, US5,914,039 and US6,354,444 uses generates through partial hydrolysis.Use the concentrated sulfuric acid to make catalyst, reaction is at high temperature carried out for a long time, and degree of hydrolysis is wayward.And alpha-alumina particle easily from casting solution partly precipitated out, precipitation degree temporal evolution, thus cause the inhomogeneous and relatively poor film reproducibility of overlay.

Said method is all in order to improve the PVDF hydrophobicity by add hydrophilic composition in casting solution, thereby improves Membrane Filtration Flux.Because, in application field of water treatment, have a kind of viewpoint to think: the membrane material of good hydrophilic property just is not easy to be blocked up by dirt, also easily clean after dirty stifled and recover, therefore have many academic documents and patent to adopt such as blend, copolymerization, grafting or crosslinked etc. the hydrophily that modification strengthens the PVDF resin is carried out on film surface or body.In fact there is not specific logical relation between the strainability of the hydrophily of polymer and membrane component.Result of study also shows, comes the antifouling property of evaluated for film that a lot of problems are arranged with hydrophily.Pollutant character in former water is very complicated on the one hand, and hydrophily practical manifestation on film in certain scope does not have conclusive impact; On the other hand, with the structure of concentration polarization, film separating layer and supporting layer, the stability influence of membrane filtration characteristic is compared, the impact of membrane material nature often can be ignored, and in fact people have exaggerated the adverse effect of hydrophobicity to membrane flux to a certain extent.Face inclined to one side with it and emphasize the initial pure water flux of membrane component with making or have much ado, not as pay close attention to more the membrane material surface with the supporting layer structure on the mechanical strength of film and the impact of strainability.Hollow-fibre membrane with unsymmetric structure characteristics is comprised of very thin and relatively fine and close surperficial separating layer and the supporting layer that relatively loosens, under ideal state, pollutant is blocked in outside selective separating, can not enter the inside of film, blocks up thereby alleviated to a certain extent irreversible dirt.The factors such as bridge formation in hole of the inhomogeneities of film surface holes in fact, the absorption between the shape of impurity particle, impurity and membrane material, impurity, winding make the perfect condition of this surface filtration not exist.So flux progressively descends, the necessity of Chemical cleaning etc. is all in esse.Can selectively prepare surperficial separating layer and the supporting layer structure of application-oriented object by designing suitable filming technology, to be adapted to the types of applications field, in fact, membrane structure is controlled the technological core that is film preparation.

But, development trend from membrane preparation technology, thin and fine and close cortex is not best structure for perforated membrane, because the perforated membrane element is usually used in serious pollution water source, as the MBR engineering, enter in the former water of membrane component and contain a large amount of solid particles, and need to bear and clean frequently for a long time and current (or air-flow) washing away on the film surface.Can cause the decline of membrane component separative efficiency after thinner like this top layer wearing and tearing.Therefore quality preferably perforated membrane should be whole asymmetry.On the one hand, surperficial separating layer has the characteristics of open-celled structure and high opening rate; On the other hand, surperficial separating layer and membrane material main body (supporting layer) are an integral body, and both are not significantly boundary at aspects such as structure, porosity, aperture sizes, just radially become gradually large from the top layer to the supporting layer aperture by little.Chinese patent (CN1099309C) discloses a kind of method that dried spray-wet spinning prepares whole asymmetry microporous membrane of polyethersulfone, the supporting layer of the doughnut poly (ether sulfone) film of the method preparation has symmetry polygon cell shape structure, the cell size changes gradually and stably from a side top layer to the opposite side top layer, briefly, composition by casting solution, and film-forming process realize controlled hole gradient, reach the separating layer percent opening high, supporting layer does not contain the purpose that macrovoid and filtration resistance are ignored.

During for the preparation of the PVDF hollow fiber porous film, the hydrophobicity that the PVDF resin is stronger makes and realizes that whole asymmetry structure faces very large difficulty when dried spray-wet spinning.Because the equal phase region of PVDF (1)-solvent (2)-water (3) ternary system is very little, after nascent membrane structure enters coagulating bath, gel occurs and forms compacted zone in the top layer within the extremely short time, thereby having hindered non-solvent spreads in the film main body, the slow the apparent phenomenon of PVDF gelation rate occurs, also caused delayed demixing and the continuous result of growing up of macropore under the top layer.Therefore be difficult to prepare with dried spray-wet spinning the hollow fiber film thread of high surperficial percent opening, and more macrovoid unavoidably appears in supporting layer.Therefore film silk flux is low, and mechanical strength is relatively poor.

Lining-reinforced hollow membrane pipe drawback of greatest concern is: the adhesive effect of surperficial separating layer and enhancement layer.More existing patents and document propose multiple solution pointedly.Wherein representative scheme can be divided three classes: the structural optimization of investment, transition zone bonding method and inner lining material.

Investment: in order to increase the bonding force of two class materials, fortifying fibre and casting solution can pass through spinning head together, then through making hollow-fibre membrane (for example CN1695777A) after the coagulating bath gel, fortifying fibre vertically is embedded in the wall of hollow-fibre membrane in this film.Perhaps, first spin out hollow-fibre membrane with casting solution, then in immersing again polymer material film liquid with synthetic fibers after this film outside is woven into net, strengthen hollow-fibre membrane (CN1864828A) through making reticular fibre after the coagulating bath gel, netted braid is embedded in the supporting layer of hollow-fibre membrane.Due to reinforcing material produce with the swing of film pipe flexible, thereby cause the structural damage of film support, too high retractility can cause non-response damage.

Transition zone bonding method: except surperficial separating layer and enhancement mode, increase a transition zone and be used for improving the adhesive force of surperficial separating layer on enhancement layer.US Patent No. 7,306,105 make enhancing braid and casting solution together by spinning head, and the hollow-fibre membrane of making after gel and the casting solution of another composition are spun into the liner hollow-fibre membrane by spinning head for the second time.Perhaps, hollow braid, adhesive and casting solution are made the liner hollow-fibre membrane by the coating head together, as patent US 7,165,682, wherein applying adhesive is on the hollow braid, casting solution covers on adhesive, and the effect of adhesive is the bond strength that increases between film and braid.Yet all there is consistency problem between layers in above-mentioned two kinds of methods, and transition zone has formed smooth interface through after gel on its surface, and surperficial separating layer can not be very firmly bonding with its formation.And adhesive contacted water as epoxy resin, polyurethane before not solidifying, and more can lose bonding performance.

Transition zone can improve the bonding force of surperficial separating layer and enhancement layer, but need to be between layers the compatibility of remaining of film preparation process, transition zone can be undertaken two other important function in fact, has on the one hand the braiding lines on stronger bonding force and the volume contraction little floating braiding enhancement layer of feature surface with it; On the other hand, transition zone should have fabulous compatibility with surperficial separating layer, becomes an overall structure on chemical feature, and on this basis, transition zone should possess more outstanding hardness and bear the ability of back pressure to improve film pipe integral body.

The structural optimization of inner lining material: United States Patent (USP) 6,354,444 disclose a kind of physical method that rete is peeled off problem that solves, and namely use dissimilar inner lining material as surperficial separating layer supporter, it has different patterns for knitting, for example regular pattern composite, god of unusual strength's type and diamond pattern.It is found that, weavy grain has better rete cohesive than rule and the tighter diamond pattern braid of god of unusual strength's braid.Yet rete is peeled off problem and is still existed.In fact, think that with it weavy grain affects the cohesive of film separating layer and enhancement layer, not as thinking: the tightness degree of weavy grain is larger on fusible impact.

Summary of the invention

For the problem that prior art exists, technical purpose of the present invention is to provide a kind of preparation facilities of lining-reinforced hollow fiber membrane tube; Another technical purpose of the present invention is to provide the method for utilizing this equipment to prepare lining-reinforced hollow fiber membrane tube; Another technical purpose of the present invention is to provide the inside bearing strip hollow fiber film tube product that utilizes the said equipment and method to prepare; By realizing technical purpose of the present invention, make that the lining-reinforced hollow fiber membrane tube that obtains has distinct surperficial separating layer, transition zone and braided tube enhancement layer three-decker.

In order to realize technical purpose of the present invention, technical scheme of the present invention is as follows.

One, a kind of lining-reinforced hollow fiber membrane tube preparation facilities mainly is comprised of casting film flow container (1), Debubbling tank (2), the former liquid storage tank of blend (3), manifold (4), transition zone precoating tank (7), coating head (8), film forming path (9), coagulating bath (10), potcher (11), godet (12) and reel (13); Wherein, described manifold (4) inside is respectively arranged with blend liquid pump (5) and casting film liquid pump (6); Applying head (8) is arranged in film forming path (9);

On the one hand, the liquid outlet of the former liquid storage tank of blend (3) connects the entrance of blend liquid pump (5) by valve, the top lateral opening of the feed liquid distribution grid (202) of the tank body (205) of the outlet connection transition zone precoating tank (7) of blend liquid pump (5), go out (202) of transition zone precoating tank (7) connect the entrance that applies head (8), and apply the outlet of head (8) and the consistent UNICOM of outlet in its residing film forming path (9); The outlet in film forming path (9) connects the entrance of coagulating bath (10), the outlet of coagulating bath (10) connects the entrance of potcher (11), and the outlet of potcher (11) connects reel (13) after connecting godet (12) again;

On the other hand, the outlet of Debubbling tank (2) connects the entrance of casting film flow container (1) by valve, the outlet of casting film flow container (1) connects the entrance of casting film liquid pump (6), and the outlet of casting film liquid pump (6) connects on coating head (8).

Further, the outer temperature and humidity control system (15) that also is connected in described film forming path (9).

Further, described transition zone precoating tank (7) is comprised of feed liquid distribution grid (202), tank body (205), connector (203) and scraping blade (204); Wherein feed liquid distribution grid (202) is arranged on the top of tank body (205), and the tank body lateral location opening above feed liquid distribution grid (202) and the outlet UNICOM of blend liquid pump (5); Connector (203) in tank body (205) is connected to scraping blade (204) interior the feed liquid distribution grid of tank body (205) (202) below, goes out above (206); Tank body (205) bottom sides opening is emptying.

Further, described film forming path (9) is comprised of airflow-distribution board (302), inner chamber (304), coating head (8), permeable wall (306) and delivery pump (303); Wherein, airflow-distribution board (302) is arranged on the top of inner chamber (304), the below of airflow-distribution board (302) arranges coating head (8), and the bottom that permeable wall (306) is arranged at coating head (8) is the bottom of inner chamber (304); Inner chamber (304) is positioned at the lateral opening of airflow-distribution board (302) top, and the lateral opening of permeable wall (306), and this two places opening is by delivery pump (303) UNICOM; The lateral opening in the exit of inner chamber (304) connects nitrogen inlet.

Further, film forming path (9) length is adjustable in 5～100 centimetres, and as preferably, path length is 5～30 centimetres.

Two, utilize lining-reinforced hollow fiber membrane tube preparation facilities claimed in claim 1 to prepare the method for lining-reinforced hollow-fibre membrane, it is characterized in that comprising the following steps.

Step 1, prepare the liner braided tube:

The liner braided tube is formed by the braiding of chemical fibre multifilament, has excellent chemical stability and mechanical strength.Material is one or both shufflings in Fypro, polyester fiber and polyurethane fibre.The factors such as count, chemical-fibres filaments dawn number, braiding number of spindles affect size and the performance of internal lining pipe.Count of the present invention is 20～60 orders, and the internal lining pipe deformation of high count is little, but yields poorly; And the problem during low-density is that percentage elongation is high, and is yielding, and then affects film pipe overall performance, and as preferably, count is 25～40 orders.The braiding number of spindles is 16～32 ingots.When the filament denier of selecting is high, can adopt 16 ingot braidings; And adopted for 24 or 32 ingots whens braiding, can be made into the internal lining pipe that has than large diameter.In addition, higher number of spindles can cause external diameter to increase, and produces the problem that easily is crushed.

Step 2, the allotment casting solution;

Wherein, described casting solution mainly is comprised of PVDF resin, solvent, non-solvent, hydrophilic macromolecule pore former and thickener; And described PVDF resin quality degree is 15%～20%, described solvent quality degree is 50%～65%, described water soluble polymer pore former mass percentage content is 10～20%, described hydrophily thickener qualities degree is 5%～15%, and described non-solvent mass percentage content is 0.5～1.5%; Hydrophily thickener, macromolecule pore former and non-solvent are dissolved in solvent, add wherein again the polyvinylidene fluoride resin raw material, be pressed into the middle vacuum defoamation of Debubbling tank (2) 4～10 hours fully after the dissolving, then change after filtering casting solution storage tank (1) over to.

Step 3, the blend stoste of preparation transition zone:

The composite that inorganic nano-particle and PVDF resin, solvent, additive blend are formed.Hydrophily thickener and water soluble polymer pore former are dissolved in solvent, add wherein again PVDF resin and nano-powder, blend forms viscosity 10,000～30,000 centipoise blend stostes, and the mass percentage content of described PVDF resin is 5%～10%, the mass percentage content of described solvent is 50%～70%, the mass percentage content of described water soluble polymer pore former is 10～20%, described hydrophily thickener qualities degree is 5%～15%, and the mass percentage content of described nano material is 0.5～5%; After being processed through deaeration, blend stoste changes in the former liquid storage tank of blend (3).

Advantage of mixing a small amount of inorganic oxide nanoparticles or macromolecular fibre in transition zone of the present invention is: adding inorganic nano-particle can combine heat-resisting, the chemical stability of inorganic material with pliability and the low cost of polymer, can improve the transition zone rigidity and and the cohesive force of surperficial separating layer and enhancement layer; Adding high polymer nanometer fiber can increase and substrate macromolecule material effect entangled to each other, strengthens intensity and the pliability of transition zone.

The nanoparticle surface active atomic is many, is easy to adsorb fully with polymer, bonding.When being subjected to external force, particle is difficult for breaking away from matrix.And because the interaction of stress field produces a lot of little deformed areas in matrix, absorb a large amount of energy.This just makes the transition zone composite can transmit preferably the external carbuncle of bearing, and can cause matrix yielding again, consumes a large amount of impact energys, thereby reaches simultaneously toughness reinforcing effect with strengthening.But the nanometer powder particle diameter is little, and surface area is large, is easy to reunite.Therefore when the compound transition zone of polymer of nanometer powder is added in preparation, be difficult to obtain the composite of nanostructured with common blending method.In order to increase the interface binding power of nanometer additive and polymer, improve the Uniform Dispersion ability of nanoparticle in macromolecular material, need nanometer powder is carried out surface modification.Surface modified powder has reduced the surperficial energy state of particle, eliminates the surface charge of nano particle, improves the affinity of nano particle and organic phase, weakens the surface polarity of nano particle etc.The present invention uses the inorganic nanometer powder of the surface modifications such as oleic acid, stearic acid, silane coupler, has strengthened nanoparticle dispersibility in polymer matrix, obtains the compound transition zone of nanostructured.The morphology microstructure that uses can be spherical, sheet, bar-shaped, columnar nanometer particle, or even nano wire, nanotube, nanometer film etc.; What the present invention preferentially used is nano wire and nano bar-shape powder, because of nano wire and the fine physical entanglement effect that generates with chain structure and polymer matrix of the existing particle of nanometer rods, have again the chemical bond effect that causes due to surface-active, show good strengthening action in polymer-filled.Adopt the transition zone composite of modified Nano powder preparation, its hot strength can increase, and fracture elongation improves, and young modulus of material increases.Although the porosity of membrane material descends to some extent, pure water flux and hydrophily increase.The present invention with solution or the direct blend of emulsion form, prepares the compound buffer layer material of nano-powder/PVDF with nano unit, macromolecule resin and other additive of modification.

Further, described nano material is hydrophobic silica, aluminium oxide, zirconia, titanium oxide inorganic nano-particle, or high polymer nanometer fiber.

Described transition zone blend stoste has lower viscosity (10,000～30,000 centipoise).At first braided tube applies blend stoste, the rough woven pattern of floating braided tube.Reach on the one hand the surface smoothness that improves surperficial separating layer, on the other hand, the not contractility of nano material causes the integral hardness of film to improve.

Step 4 is coated on the liner braided tube with blend stoste surperficial:

Control the temperature of manifold (4) at 25～95 ℃, enter in tank body (205) blend stoste is pressed into the feed liquid distribution grid (202) of precoating tank (7) from the former liquid storage tank of blend (3) by blend liquid pump (5) after; Simultaneously, liner braided tube (201) penetrates from tank body (205) top, scrape floating whole weavy grain gap through the scraping blade (204) that is fixed in both sides in tank by connector (203) in tank body (205), obtain drawing from tank body (205) outlet at bottom (206) again with the liner braided tube that blend stoste is scraped after smearing.Tank body (205) bottom sides arranges evacuation port, is conducive on the one hand discharge air to the slack tank material feeding time, facilitates on the other hand the cleaning operation of precoating tank, when equipment normally moves, is normally off.

Manifold (4) is the square box of a Plate Welding, in establish the circulating hot water passage.Manifold is provided with the spin manifold temperature demonstration and casting solution pressure shows.The temperature controlled range of manifold is 25～95 ℃, and as preferably, the Temperature Setting of manifold is between 50～80 ℃.Casting film liquid pump (6) all is placed in manifold with blend liquid pump (5), makes the temperature of casting solution and blended liquid keep stable before being coated on braided tube.

At first by precoating tank (7), the essential structure of precoating tank as shown in Figure 4 for braided tube (201).The blended liquid that is mixed with inorganic particulate is pressed into by blend liquid pump (5), through entering after feed liquid distribution grid (202) in tank (205), braided tube penetrates from the tank body top, tank base outlet (206) is drawn, in tank body, two scraping blades (204) are fixed in both sides in tank by connector (203), are used for the weavy grain gap of floating braided tube.

Step 5, the liner braided tube surface that is coated with blend stoste applies casting solution again:

The liner braided tube (201) of passing precoating tank (7) enters film forming path (9), at first passes through airflow-distribution board (302), then continues across coating head (8) in inner chamber (304); By casting film liquid pump (6), casting solution is pressed into by casting solution storage tank (1) on the one hand and applies head (8), apply casting solution by coating head (8) outside being coated with the liner braided tube of blend stoste simultaneously, obtain nascent film pipe (305); Delivery pump (303) will be carried mixed vapour from bottom to up in inner chamber (304), make nascent film pipe (305) process vapor phase conversion process in film forming path (9), namely begin to take shape the surperficial separating layer (101) of film of porous outside nascent film pipe (305); Permeable wall (306) is made as porous ceramics or sintered stainless steel by the anti-solvent material of porous, is used for strengthening the uniformity that air-flow distributes in the path.Control the nitrogen input quantity of the nitrogen inlet humidity in can complementary ground regulation channel.

The braided tube (201) of passing precoating tank (7) enters film forming path (9), and the structure in film forming path as shown in Figure 5.Mainly consisted of by airflow-distribution board (302), inner chamber (304), permeable wall (306).And the outer coating of coating head (8), coating head (8) is placed in the top in film forming path.The bottom, path is near coagulating bath.Braided tube (201) continues across the coating head in the film forming path, the nascent film pipe (305) of outside coating blend stoste and casting solution is process vapor phase conversion process in the path, the film pipe outside begins to take shape the surperficial separating layer of porous, path length is adjustable in 5～100 centimetres, as preferably, path length is 5～30 centimetres, when coating speed is slow, select less length, the solvent on film silk surface and the double diffusive process of non-solvent make the time of staying of film pipe in the path keep stable, because can be completed within the extremely short time.And the long time only can cause the excessive volatilization of film tube outer surface solvent.The path lower ending opening also stretches into coagulating bath, so the solvent in coagulating bath and non-solvent also can spread in the path, thereby affects the content of temperature, solvent and non-solvent in the path.

Temperature in the film forming path, moisture and solvent are strictly controlled.In such a in check atmosphere, the separating layer partial solvent of film tube outer surface volatilizees and absorbs the moisture in surrounding environment and tentatively solidify.Temperature in the path affects the feature that balances each other of volatile quantity and the casting solution of solvent, and the convection current diffusion rate of the moisture in the path and solvent major effect solvent-nonsolvent.

Further, to control temperature by temperature and humidity control system (15) be that in the scope of 40～80 ℃, humidity is 50～90% described film forming path.

By add these parts of path in the coating membrane equipment, vapor phase is transformed with immersion inversion of phases process be combined.Nascent film separating layer is experience vapor phase conversion process in the path at first, be not separated even do not produce, the casting solution on top layer forms also can be because solvent evaporates, moisture penetration change, this variation will help the uniformity of casting solution phase separation speed in coagulating bath, thereby produce the surface of high opening rate.After the internal lining pipe of surface coating casting solution enters coagulating bath, the surface with high opening rate more be conducive to non-solvent by the coagulating bath main body to the overlay diffused inside, make film separating layer and transition zone after moulding be whole asymmetrical cell shape structure.

Step 6, the immersion inversion of phases occurs and the gel typing in nascent film pipe (305) in the coagulating agent of coagulating bath (10), and described coagulating agent is the mixture of solvent and water, and wherein the mass percentage content of solvent is 30%～60%, and the temperature of coagulating agent is 30 ℃～90 ℃; Inner lining film pipe silk journey of process in described coagulating bath is 10～30 meters;

The inner lining film pipe of completing the vapor phase conversion process in the film forming path enters the coagulating basin below the path, and immersion inversion of phases process occurs.The coagulating agent of coagulating basin is the mixture of solvent and non-solvent.

In coagulating bath, the typing of skin covering of the surface separating layer and transition zone generation immersion inversion of phases and gel.Therefore the distance of film pipe process in coagulating bath (silk journey) is decided according to gelation rate and coating speed, and gelation rate is subjected to the composition of coagulating bath and the impact of temperature.Further, the distance of inner lining film pipe process in described coagulating bath (silk journey) is 10～30 meters.According to result of the test, the silk journey of preferred coagulating bath is 5～10 meters.After separating layer and transition zone are separated, form polymer rich stingy with polymer, richness develops into the main body of this double-layer structure mutually, stingyly is comprised of solvent, non-solvent and most additive, can dissolve each other with water.

Step 7, the nascent film pipe that does not solidify fully enters potcher (11).Further complete process of setting, replace simultaneously solvent residual in the membrane pipe and additive.The distance of described film pipe process in potcher is 30～60 meters.Potcher medium be pure water, its temperature is 25 ℃～95 ℃.

Step 8, the film pipe is collected bunchy through godet (12) by reel (13), puts into tank and soaks 24 hours, thoroughly displaces solvent and additive.Water in tank will be incessantly be replaced in the mode that flows, and purpose is to make the solvent in the film pipe and additive is faster removes more up hill and dale.

Step 9, the glycerine moisturizing is processed.Soak being placed in glycerine water solution again after the dried free moisture content of film management and control, the hole of film tube-surface separating layer can further farthest kept in dry run, also reduce the shrinkage factor of film separating layer and transition zone simultaneously.Described film pipe soak time in glycerine water solution is 12～24 hours, and wherein the quality of glycerine is 10%～50% than concentration.As preferably, the quality of glycerine is 20%～30% than concentration.

Step 10 is carried out drying with the film pipe and is processed, and namely obtains described lining-reinforced hollow membrane pipe.

In the method for the invention, the weight average molecular weight of described PVDF resin is between 20～800,000 dalton, and alternative PVDF resin brand has: Kynar 461, Kynar 740, Kynar 760, and Kynar 761, and HSV 900, FR 904, Solef 1010, and Solef 1015, and Solef 6010, Solef 6020, and Solef 6030 and other weight average molecular weight are greater than 200,000 resin.Have as preferred brand: Kynar 760, and Kynar 761, and HSV 900, and FR 904, and Solef 1010, and Solef 1015, and Solef 6020, and Solef 6030.

Further, described solvent is a kind of in 1-METHYLPYRROLIDONE (NMP), dimethyl formamide (DMF), dimethylacetylamide (DMAC), dimethyl sulfoxide (DMSO) (DMSO).These four kinds of fine solvents that reagent is all the PVDF resin be to be simplified the composition of formula, only select wherein a kind of.Because the solvability to PVDF is similar, so consumption is basic identical.As preferably, solvent is selected dimethylacetylamide (DMAC) and 1-METHYLPYRROLIDONE (NMP).

Further, described non-solvent is that one or more of water, ethanol, isopropyl alcohol, glycerine, n-butanol, ethylene glycol, diglycol mix.Non-solvent is the material that causes that casting solution is separated, and causes the overlay gel solidification.Add non-solvent in casting solution, can accelerate the inner phase separation of overlay.Add the amount of non-solvent very crucial.Non-solvent is stronger, and consumption is fewer.In addition, strong, the weak non-solvent use of can arranging in pairs or groups.As preferably, described non-solvent is water or glycerine.When selecting strong non-solvent water, consumption is less than 1.0%.

Further, described hydrophily thickener is one or more mixtures in GBL, phosphorus benzene bis-acid potassium dibutyl ester, low molecular polyethylene glycol (MW:200～600), polyvinyl alcohol (MW:200～600).Add appropriate hydrophily thickener in casting solution after, can regulate and control the viscosity of casting solution, increase equal phase region scope, also can promote the diffusion of non-solvent ecto-entad simultaneously, overall effect is that the finger-like pore that suppresses in supporting layer occurs.

Further, described water soluble polymer pore former is high molecular weight polyethylene glycol (MW:2,000～10,000), PEO (MW:10,000～50,000), polyvinyl alcohol (MW:10,000～50,000), one or more mixtures in polyvinylpyrrolidone (MW:10,000～400,000).Water-soluble pore former except the effect that possesses described thickener, due in the rinse cycle after gelation constantly with solvent elution out, and increase the porosity of supporting layer.As preferably, the macromolecule pore former is that PEG is or/and PVP.The range of choice of the molecular weight of described PVP is between 10000～100000, and the molecular weight of described PEG is between 1000～10000.

Three, the lining-reinforced hollow fiber membrane tube for preparing according to method of the present invention.

Inside bearing strip enhancement type hollow fiber film pipe of the present invention is by the surperficial separating layer (101) of film, transition zone (103) and (104) three layers of formation of braided tube enhancement layer, as shown in Figure 1.Film surface separating layer (101) is the function body of hollow membrane pipe, by the preparation of diffusion phase conversion method, is whole asymmetry structure, and material is the polyvinylidene fluoride resin that pliability is good, oxidation resistance is strong.Transition zone (103) is used for improving the rigidity of film pipe, and the bonding force of overlay and enhancement layer, and thickness is 0.05～0.15mm, and material is the composite of polyvinylidene fluoride resin and inorganic nano-particle, nanometer rods or nano-fibre blend.Braided tube enhancement layer (104) is formed by the braiding of chemical fibre multifilament, has excellent chemical stability and mechanical strength.Thickness is 0.3～0.7mm.

Beneficial effect of the present invention is:

At first, the standby technology of the lining-reinforced hollow membrane control that proposes by the present invention produce the film pipe, overlay has good whole asymmetry, the cell shape structure that is IPN, do not form the macrovoid that affects the membrane material separative efficiency, so the film pipe has improved the ratio in active hole under the prerequisite that does not increase porosity.The transition zone hardness of being made by composite is high, and in film liquid-phase conversion process, the transition zone cubical contraction is little, so the ability that the film pipe bears back pressure has reduced over 0.35MPa the probability that the film separating layer is peeled off from enhancement layer.The enhancement layer count is high, and axial percentage elongation is minimum, so the film pipe also can not damage the overlay of film pipe under fluid impact.

Secondly, the present invention passes through: the film forming path that (1) is reasonable in design, enter coagulating bath after at first overlay on the coating head braided tube of drawing causes inversion of phases through controlled diffusion of vapor, make the film separating layer form the open surface cortex of high porosity, thereby cause the cell shape structure of whole asymmetric and IPN of radially being of rete; (2) select composite to prepare transition zone, make transition zone have simultaneously good bonding force and hardness, possess cubical contraction minimum in the compatibility good with surperficial separating layer, inversion of phases process; (3) select braided tube size and the count of optimization, make braided tube have very low retractility, the methods such as rational roundness be can safeguard in process of production, the good whole asymmetry structure of the standby integrality of inside bearing strip PVDF hollow fiber ultrafiltration film pipe, high opening rate surface separating layer and the higher advantages such as back pressure ability to bear made.

At last, the present invention designs suitable film forming path, diffusion of vapor is caused inversion of phases to be caused the inversion of phases process with sovent diffusion and is combined, make overlay at first form the top layer of high opening rate, with the solvent after quickening overlay immersion coagulating bath and the reverse diffusion process of non-solvent, it is advantageous that: film separating layer structure is tending towards whole asymmetry, as shown in Figure 1.In figure (101), (103) are respectively film separating layer and transition zone.From the cross-section of face, even structure does not have the described macrovoid of Fig. 4 (102), and transition zone is more loose, and desirable film separating layer has the high surface of percent opening (105).In contrast, a lot of diffusions cause the polymeric membrane cross section of inversion of phases method preparation and usually find macrovoid, this structure affects the mechanical performance of membrane material on the one hand, on the other hand can be because shrinkage stress cause defective in dry run, its comprehensive result is to make the membrane module can't be by integrity test.For inside bearing strip film Guan Eryan, although do not affect the overall mechanical properties of membrane material, the disappearance of integrality aspect still merits attention.Have macroporous inner lining film pipe and have feature shown in Figure 2.

Description of drawings

Fig. 1 is lining-reinforced film pipe schematic diagram (24 ingot);

Wherein, 101-film surface separating layer; The 103-transition zone; 104-braided tube enhancement layer; The 105-surface.

Fig. 2 is lining-reinforced film pipe schematic diagram (16 ingot);

Fig. 3 is lining-reinforced film pipe schematic diagram (32 ingot);

Fig. 4 is the lining-reinforced hollow membrane pipe schematic diagram that contains macroporous structure;

Wherein, 101-film surface separating layer; The 102-macrovoid; The 103-transition zone; 104-braided tube enhancement layer; The 105-surface.

Fig. 5 is lining-reinforced hollow fiber membrane tube preparation facilities schematic diagram of the present invention;

Wherein, 1-casting film flow container; The 2-Debubbling tank; The former liquid storage tank of 3-blend; The 4-manifold; 5-blend liquid pump; 6-casting film liquid pump; 7-transition zone precoating tank; 8-applies head; 9-film forming path; The 10-coagulating bath; The 11-potcher; The 12-godet; The 13-reel.

Fig. 6 is precoating tank schematic diagram;

Wherein, 201-liner braided tube; 202-feed liquid distribution grid; The 203-connector; The 204-scraping blade; The 205-tank body; The 206-outlet; 5-blend liquid pump.

Fig. 7 is film forming path and appurtenances schematic diagram;

Wherein, 201-liner braided tube; The 302-airflow-distribution board; The 303-delivery pump; The 304-inner chamber; The 305-film pipe of coming into being; The 306-permeable wall; 8-applies head.

Fig. 8 is the Nano bars of alumina electromicroscopic photograph.

Fig. 9 is lining-reinforced hollow membrane pipe (example 1).

Figure 10 is lining-reinforced hollow membrane pipe (comparative example 1).

The specific embodiment

Embodiment 1

Structure and the structure of the present embodiment explanation lining-reinforced doughnut membrane preparation device of the present invention.

Lining-reinforced doughnut membrane preparation device of the present invention, mainly by casting film flow container 1, Debubbling tank 2, the former liquid storage tank 3 of blend, manifold 4, transition zone precoating tank 7, apply head 8, film forming path 9, coagulating bath 10, potcher 11, godet 12 and reel 13 and form; Wherein, described manifold 4 inside are respectively arranged with blend liquid pump 5 and casting film liquid pump 6; Applying head 8 is arranged in film forming path 9;

On the one hand, the liquid outlet of the former liquid storage tank 3 of blend connects the entrance of blend liquid pump 5 by valve, the top lateral opening of the feed liquid distribution grid 202 on the tank body 205 of the outlet connection transition zone precoating tank 7 of blend liquid pump 5, the outlet 202 of transition zone precoating tank 7 connects the entrance that applies heads 8, and the consistent UNICOM of outlet in the outlet that applies head 8 and its residing film forming path 9; The outlet in film forming path 9 connects the entrance of coagulating bath 10, and the outlet of coagulating bath 10 connects the entrance of potcher 11, and the outlet of potcher 11 connects reel 13 after connecting godet 12 again;

On the other hand, the outlet of Debubbling tank 2 connects the entrance of casting film flow container 1 by valve, and the outlet of casting film flow container 1 connects the entrance of casting film liquid pump 6, and the outlet of casting film liquid pump 6 connects on coating head 8.

Further, the outer temperature and humidity control systems 15 that also are connected in described film forming path 9.

Further, described transition zone precoating tank 7 is comprised of feed liquid distribution grid 202, tank body 205, connector 203 and scraping blade 204; Wherein feed liquid distribution grid 202 is arranged on the top of tank body 205, and the outlet UNICOM of the tank body lateral location opening above feed liquid distribution grid 202 and blend liquid pump 5; Connector 203 in tank body 205 is connected to the interior feed liquid distribution grid of tank body 205 202 belows, outlet 206 tops with scraping blade 204; Tank body 205 bottom sides openings are emptying.

Further, described film forming path 9 by airflow-distribution board 302, inner chamber 304, apply head 8, permeable wall 306 and delivery pump 303 and form; Wherein, airflow-distribution board 302 is arranged on the top of inner chamber 304, and the below of airflow-distribution board 302 arranges coating head 8, and the bottom that permeable wall 306 is arranged at coating head 8 is the bottom of inner chamber 304; Inner chamber 304 is positioned at the lateral opening of airflow-distribution board 302 tops, and the lateral opening of permeable wall 306, and this two places opening is by delivery pump 303 UNICOMs; The lateral opening in the exit of inner chamber 304 connects nitrogen inlet.

Further, film forming path 9 length are adjustable in 5～100 centimetres, and as preferably, path length is 5～30 centimetres.

Embodiment 2

The present embodiment explanation utilizes the described lining-reinforced hollow fiber membrane tube preparation facilities of embodiment 1 to prepare the method for lining-reinforced hollow fiber membrane tube.

Step 1, prepare the liner braided tube:

Step 2, the allotment casting solution;

Step 3, the blend stoste of preparation transition zone:

Step 4 is coated on the liner braided tube with blend stoste surperficial:

Embodiment 3

The present embodiment prepares hollow fiber film tube according to the method for embodiment 2, and the condition of wherein selecting and the film pipe character for preparing are as follows:

Select the chemical-fibres filaments polyester fiber to prepare braided tube, braided tube density is 45 orders, and the braiding number of spindles is 24 ingots, gained braided tube external diameter 1.65mm, internal diameter 0.85mm.Select the polyvinylidene fluoride resin blend of 900 two kinds of different weight average molecular weight of Solef 1010 and HSV to be modulated into casting solution, solvent is selected dimethylacetylamide (DMAC), and content is 56%.Macromolecular water-soluble pore former, hydrophily thickener and non-solvent are selected respectively polyvinylpyrrolidone (PVP) K17, PEG400 and glycerine, and the content of each composition is listed in table 1.Above raw material is by solid after first liquid, and after first small-molecular weight, the order of macromolecule drops in reactor, stirs under 75～80 ℃ and makes uniform buff casting solution, and casting solution viscosity is 58000 centipoises (80 ℃).Changed in the Debubbling tank of uniform temp deaeration after dissolve complete over to 8 hours, it is stand-by that the casting solution after deaeration is pressed into fluid reservoir with clean air.Gear wheel metering pump is clamp-oned coating head with casting solution from fluid reservoir with constant speed.

Blend stoste for the preparation of transition zone adopts the raw material similar to casting solution, and the main content that is not both the PVDF resin is low, and has added the Al of oleic acid modification ₂O ₃Nanometer rods, as shown in Figure 6, particle diameter is 30nm approximately.Each component content in blended liquid is listed in table 1.Concocting method and the casting solution of blended liquid are similar, and each component drops in reactor successively, stir under 75～80 ℃, to change the blended liquid storage tank over to through deaeration, after standing stand-by.Gear wheel metering pump is clamp-oned precoating tank with blended liquid from fluid reservoir with constant speed.

Table 1, casting solution and blended liquid form

Braided tube by precoating tank and coating head, enters the film forming path successively under the traction of reel.The elongated degree in river in Zhejiang Province is 15 centimetres, contains 50% solvent in coagulating bath, and the temperature of coagulating bath is controlled at 80 ℃, and the film silk is 40 seconds in the time of staying of coagulating bath.The medium of potcher is water, and temperature is controlled at 80 ℃, and the film silk is 60 seconds in the time of staying of potcher.Coating speed is 12 meter per seconds.Film Guan Jing solidifies, rinsing and reel after, put into the water rinsing, and the film pipe carried out the glycerine moisturizing, after the drying process, vanning is stand-by.Fig. 9 is the electromicroscopic photograph of the film lining-reinforced film tube section of this example preparation.Can find from the SEM photo, inner liner braiding lines is tight, and overlay (surperficial separating layer and transition zone) average thickness is 0.1mm, there is no macrovoid.The back pressure test result of finished film pipe shows overlay and inner liner anti-peel off pressure, and film envelope point pressure all over 0.3MPa, the pure water stabilized flux of film pipe can reach 450LMH/bar.

Comparative example:

Adopt liner braided tube weaving method and the coated technique identical with embodiment 3, but the braiding number of spindles of internal lining pipe is 32, changes formula of casting and blended liquid formula such as table 2.Therefore, dried film pipe has the external diameter larger than example 3 on macroscopic view, external diameter 2.0mm, internal diameter 1.4mm.Simultaneously cause the cross section to present macroporous structure because the content of polymeric additive is low.When carrying out the integrity test of film pipe, bubble point pressure is lower than 0.02MPa.

Table 2, casting solution and blended liquid form (comparative example)

Embodiment 4

The preparation method of braided tube is consistent with embodiment 3.Select Kynar 761 resins as the main component of casting solution, because the weight average molecular weight of Kynar 761 resins is lower than HSV900, so the total amount of resin is 20% of casting solution gross weight.Solvent is dimethylacetylamide (DMAC), and composition and the proportioning of casting solution and blended liquid are listed in table 3.Above material is by solid after first liquid, and after first small-molecular weight, the order of macromolecule drops in agitator tank, stirs under 75～80 ℃ and makes uniform buff casting solution, and casting solution viscosity is 53000 centipoises (80 ℃).Coating process such as example 3.The back pressure test result of finished film pipe shows overlay and inner liner anti-peel off pressure, and film envelope point pressure all over 0.3MPa, the pure water stabilized flux of film pipe can reach 500LMH/bar.

Table 3, casting solution and blended liquid form

Composition	Casting solution	Blended liquid
			PVDF，Kynar 761	20％	10.0％
DMAC	55.0％	64.0％

PVP，K30	14.0％	14.0％
			PEG 400	10.0％	10.0％
GLY	1.0％	0.0％
			Al ₂O ₃	0.0％	2.0％

Embodiment 5

Select the chemical-fibres filaments polyurethane fibre to prepare braided tube, braided tube density is 20 orders, and the braiding number of spindles is 16 ingots, gained braided tube external diameter 1.50mm, internal diameter 0.50mm.Select the polyvinylidene fluoride resin blend of FR904 and 1,015 two kinds of different weight average molecular weight of Solef, the total amount of resin is that 19%, two kind of resin of casting solution gross weight is mixed with the ratio of 8: 2.Solvent is 1-METHYLPYRROLIDONE (NMP), and composition and the proportioning of casting solution and blended liquid are listed in table 4.Above material is by solid after first liquid, and after first small-molecular weight, the order of macromolecule drops in agitator tank, stirs under 75～80 ℃ and makes uniform buff casting solution, and the viscosity of casting solution is similar to example 4, is 55000 centipoises (80 ℃).Coating process such as example 1, the back pressure test result of finished film pipe show overlay and inner liner anti-peel off pressure, and film envelope point pressure all over 0.3MPa, the pure water stabilized flux of film pipe can reach 500L/ (m ²Hrbar).

Table 4, casting solution and blended liquid form

Composition	Casting solution	Blended liquid
			PVDF，FR904	15.2％	10.0％
PVDF，Solef 1015	3.8％	0.0％
			NMP	56.0％	64.0％
PVP，K17	14.0％	14.0％
			PEG 400	10.0％	10.0％
GLY	1.0％	0.0％

Al ₂O ₃

0.0％

2.0％

Embodiment 6～11

Adopt the equipment and technology of embodiment 2 to prepare lining-reinforced pvdf membrane pipe, material used, technological parameter and film pipe performance are listed in table 5.

Claims

1. a lining-reinforced hollow fiber membrane tube preparation facilities, mainly be comprised of casting film flow container (1), Debubbling tank (2), the former liquid storage tank of blend (3), manifold (4), transition zone precoating tank (7), coating head (8), film forming path (9), coagulating bath (10), potcher (11), godet (12) and reel (13); Wherein, described manifold (4) inside is respectively arranged with blend liquid pump (5) and casting film liquid pump (6); Applying head (8) is arranged in film forming path (9);

On the one hand, the liquid outlet of the former liquid storage tank of blend (3) connects the entrance of blend liquid pump (5) by valve, the top lateral opening of the feed liquid distribution grid (202) on the tank body (205) of the outlet connection transition zone precoating tank (7) of blend liquid pump (5), the outlet of transition zone precoating tank (7) connects the entrance that applies head (8), and applies the outlet of head (8) and the consistent UNICOM of outlet in its residing film forming path (9); The outlet in film forming path (9) connects the entrance of coagulating bath (10), and the outlet of coagulating bath (10) connects the entrance of potcher (11), and the outlet of potcher (11) connects reel (13) after connecting godet (12) again;

On the other hand, the outlet of Debubbling tank (2) connects the entrance of casting film flow container (1) by valve, and the outlet of casting film flow container (1) connects the entrance of casting film liquid pump (6), and the outlet of casting film liquid pump (6) connects coating head (8).

2. lining-reinforced hollow fiber membrane tube preparation facilities according to claim 1, is characterized in that the external temperature and humidity control system in described film forming path (9) (15).

3. lining-reinforced hollow fiber membrane tube preparation facilities according to claim 1, is characterized in that described transition zone precoating tank (7) is comprised of feed liquid distribution grid (202), tank body (205), connector (203) and scraping blade (204); Wherein feed liquid distribution grid (202) is arranged on the top of tank body (205), and the tank body lateral location opening above feed liquid distribution grid (202) and the outlet UNICOM of blend liquid pump (5); Connector (203) in tank body (205) is connected to scraping blade (204) above interior the feed liquid distribution grid of tank body (205) (202) below, outlet (206); Tank body (205) bottom sides opening is emptying.

4. lining-reinforced hollow fiber membrane tube preparation facilities according to claim 1, is characterized in that described film forming path (9) is comprised of airflow-distribution board (302), inner chamber (304), coating head (8), permeable wall (306) and delivery pump (303); Wherein, airflow-distribution board (302) is arranged on the top of inner chamber (304), and the below of airflow-distribution board (302) arranges coating head (8), and the bottom that permeable wall (306) is arranged at coating head (8) is the bottom of inner chamber (304); Inner chamber (304) is positioned at the lateral opening of airflow-distribution board (302) top, and the lateral opening of permeable wall (306), and this two places opening is by delivery pump (303) UNICOM; The lateral opening in the exit of inner chamber (304) connects nitrogen inlet.

5. lining-reinforced hollow fiber membrane tube preparation facilities according to claim 4, is characterized in that described film forming path (9) length is 5～100 centimetres.

6. utilize lining-reinforced hollow fiber membrane tube preparation facilities claimed in claim 1 to prepare the method for lining-reinforced hollow-fibre membrane, it is characterized in that comprising the following steps:

Step 1, prepare the liner braided tube: selecting count is 20～60 orders, the braiding number of spindles is the chemical fibre multifilament of 16～32 ingots; Wherein, the material of chemical fibre multifilament is one or both in Fypro, polyester fiber and polyurethane fibre;

Step 2, the allotment casting solution: wherein, described casting solution mainly is comprised of PVDF resin, solvent, non-solvent, hydrophilic macromolecule pore former and hydrophily thickener; And described PVDF resin quality degree is 15%～20%, described solvent quality degree is 50%～65%, described hydrophilic macromolecule pore former mass percentage content is 10～20%, described hydrophily thickener qualities degree is 5%～15%, and described non-solvent mass percentage content is 0.5～1.5%; Hydrophily thickener, hydrophilic macromolecule pore former and non-solvent are dissolved in solvent, then add wherein the PVDF resin, be pressed into the middle vacuum defoamation of Debubbling tank (2) 4～10 hours fully after the dissolving, then change after filtering casting solution storage tank (1) over to;

step 3, the blend stoste of preparation transition zone: with the hydrophily thickener, the hydrophilic macromolecule pore former is dissolved in solvent, add wherein again PVDF resin and nano-powder, blend forms viscosity 10,000～30,000 centipoise blend stostes, and the mass percentage content of described PVDF resin is 5%～10%, the mass percentage content of described solvent is 50%～70%, the mass percentage content of described hydrophilic macromolecule pore former is 10～20%, described hydrophily thickener qualities degree is 5%～15%, the mass percentage content of described nano-powder is 0.5～5%, after being processed through deaeration, blend stoste changes in the former liquid storage tank of blend (3), wherein, described nano-powder is selected from inorganic oxide nanoparticles or macromolecular fibre,

Step 4, blend stoste is coated on liner braided tube surface: control the temperature of manifold (4) at 25～95 ℃, enter in tank body (205) blend stoste is pressed into the feed liquid distribution grid (202) of precoating tank (7) from the former liquid storage tank of blend (3) by blend liquid pump (5) after; Simultaneously, liner braided tube (201) penetrates from tank body (205) top, scrape floating whole weavy grain gap through the scraping blade (204) that is fixed in both sides in tank by connector (203) in tank body (205), obtain drawing from tank body (205) outlet at bottom (206) again with the liner braided tube that blend stoste is scraped after smearing;

Step 5, the liner braided tube surface that is coated with blend stoste applies casting solution again: the liner braided tube (201) of passing precoating tank (7) enters film forming path (9), at first pass through airflow-distribution board (302), then continue across coating head (8) in inner chamber (304); By casting film liquid pump (6), casting solution is pressed into by casting solution storage tank (1) on the one hand and applies head (8), by applying head (8) being coated with the liner braided tube outside coating casting solution of blend stoste, obtain nascent film pipe (305) simultaneously; Delivery pump (303) will be carried mixed vapour from bottom to up in inner chamber (304), make nascent film pipe (305) process vapor phase conversion process in film forming path (9), namely begin to take shape the surperficial separating layer (101) of film of porous outside nascent film pipe (305); It is 40～80 ℃ that temperature is controlled by temperature and humidity control system (15) in described film forming path, and humidity is 50～90%;

Step 7, the nascent film pipe that does not solidify fully enters potcher (11), further completes process of setting, replaces simultaneously solvent residual in the membrane pipe and additive; Described film pipe silk journey of process in potcher is 30～60 meters; Potcher medium be pure water, its temperature is 25 ℃～95 ℃;

Step 8, the film pipe is collected bunchy through godet (12) by reel (13), puts into tank and soaks 24 hours, thoroughly displaces solvent and additive;

Step 9, the glycerine moisturizing is processed: soak being placed in glycerine water solution after the dried free moisture content of film management and control again, the hole of film tube-surface separating layer can further farthest kept in dry run, also reduce the shrinkage factor of film separating layer and transition zone simultaneously; Described film pipe soak time in glycerine water solution is 12～24 hours, and wherein the mass percent concentration of glycerine is 10%～50%;

Step 10 is carried out drying with the film pipe and is processed, and namely obtains lining-reinforced hollow membrane pipe.

7. method according to claim 6, is characterized in that the establishment density of selecting in described step 1 is 25～40 orders.

8. method according to claim 6, is characterized in that the nano-powder described in described step 3 is hydrophobic silica, aluminium oxide, zirconia, titanium oxide inorganic nano-particle, or high polymer nanometer fiber.

9. method according to claim 6, the temperature that it is characterized in that manifold in described step 4 is 50～80 ℃.

10. method according to claim 6 is characterized in that the weight average molecular weight 20 of the PVDF resin described in described step 2, step 3～800,000 dalton; And be Kynar 461, Kynar 740, and Kynar 760, and Kynar 761, and HSV 900, and FR 904, and Solef 1010, and Solef 1015, and Solef 6010, and Solef 6020, and perhaps Solef 6030.

11. method according to claim 10 is characterized in that described PVDF resin is Kynar 760, Kynar 761, and HSV 900, and FR 904, and Solef 1010, and Solef 1015, and Solef 6020, and perhaps Solef 6030.

12. method according to claim 6 is characterized in that the solvent described in described step 2, step 3 or step 6 is 1-METHYLPYRROLIDONE, dimethyl formamide, dimethylacetylamide or dimethyl sulfoxide (DMSO).

13. method according to claim 6 is characterized in that the solvent described in described step 2, step 3 or step 6 is dimethylacetylamide or 1-METHYLPYRROLIDONE.

14. method according to claim 6 is characterized in that the non-solvent described in described step 2 is water, ethanol, isopropyl alcohol, glycerine, n-butanol, ethylene glycol, diglycol or its combination.

15. method according to claim 14 is characterized in that described non-solvent is water.

16. method according to claim 6, it is characterized in that the hydrophily thickener described in described step 2, step 3 is that GBL, phosphorus benzene bis-acid potassium dibutyl ester, molecular weight are that 200～600 polyethylene glycol, molecular weight are 200～600 polyvinyl alcohol or its combination.

17. method according to claim 6, it is characterized in that the hydrophilic macromolecule pore former described in described step 2, step 3 is that molecular weight is 2,000～10,000 polyethylene glycol, molecular weight are 10,000～50,000 PEO, molecular weight are 10,000～50,000 polyvinyl alcohol, molecular weight are 10,000～400,000 polyvinylpyrrolidone, perhaps its combination.

18. method according to claim 6, it is characterized in that the hydrophilic macromolecule pore former described in described step 2, step 3 is that polyethylene glycol is or/and polyvinylpyrrolidone, and the range of choice of the molecular weight of described polyethylene glycol is 10000～100000, and the molecular weight of described polyvinylpyrrolidone is 1000～10000.

19. the lining-reinforced hollow membrane pipe that method according to claim 6 prepares.