JPH01203004A - Filter system - Google Patents

Abstract

PURPOSE:To filter solution containing considerably rough suspended material with small energy loss by moving a membrane separating unit consisting of a plurality of laminated membrane supporting sheets covered with a semipermeable membrane reciprocatingly in a treatment tank. CONSTITUTION:A membrane unit 3 consisting of membrane sheets 1, constituted of membrane supporting sheets covered with a semipermeable membrane, laminated at given intervals 2, is mounted on support fitments 4, 4' moving reciprocatingly and immersed in a solution tank 5 for filtering. Filtering is carried out by means of suction or pressurizing while the membrane unit 3 is moved reciprocatingly. Fluid having permeated the membrane flows through a permeating fluid flow channel formed between the membrane supporting sheets and the membrane and a collection tube 6 and discharged out of a permeable fluid discharge tube 7. Solution between membrane sheets are fluidized hard by the periodical turnover in the moving direction of the membrane unit generated by its reciprocating movement to control the concentration polarization and carry out filtration with good efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a reciprocating filtration system, and more particularly to a filtration device and a fluid separation device with excellent permeation rates.

(Prior art and problems to be solved by the invention) In general, a separate separation device is installed to control the concentration in a reaction tank such as a bioreactor or a plating bath, to separate biological a-substances outside the system, or to remove inhibitory substances. This is carried out by guiding it out of the system with a pump or the like and treating it. In such a method, the energy required for stirring and the like in the reaction tank is still required, and the equipment is complicated, and a large area is required for the equipment.

In addition, for example, pressure plate modules are used in the filtration process of sewage treatment, but in order to increase the permeation efficiency of the membrane at a certain amount of raw water circulation, the gap between the pressure plates equipped with membranes is extremely large, ranging from 1 to 21 layers. It's narrow. Therefore, before filtration, large suspended particles in the raw water must be removed through fine-grained slits; if large suspended particles are not removed, the module will block the raw water flow path, a simple pretreatment with coarse slits. If membrane filtration is to be performed by using only one membrane, the gap between the pressure plates must be widened to avoid clogging of the raw water passage by suspended matter. However, if the width is increased, the amount of raw water supplied per unit membrane area will increase, resulting in an increase in processing energy. Furthermore, in general, the amount of membrane permeation of these existing membrane modules relative to the amount of circulating raw water is only about 1 to 2%, and the raw water must be circulated several thousand times to achieve several times the concentration.

Furthermore, when filtering a high viscosity solution using an existing module, there is a very large energy loss not only within the module but also in piping, pumps, etc.

It is an object of the present invention to provide a new filtration system that overcomes these difficulties in conventional filtration processes.

(Means for solving problems) The above objectives were achieved by the filtration system described below.

That is, 1. 1) A membrane separation unit consisting of a plurality of membrane support plates laminated at a predetermined interval with translucent and covered permeate fluid passages is installed in a processing tank in a reciprocating manner and immersed in the processing tank. A pressure plate type reciprocating filtration device characterized in that a permeated fluid is taken out by reciprocating motion of a membrane separation unit.

2) One membrane separation unit is fixed in the processing tank, and the movable membrane separation units arranged to alternately engage with the membrane sheet plates of the fixed membrane separation unit are reciprocated to collect permeation from both membrane separation units. A fluid separation device characterized in that the fluid is taken out, and 3) membrane biochemistry involving filtration using either the fixed membrane separation unit or the movable membrane separation unit of 2) above as a stationary phase for bacterial cells or enzymes. It is a reactor.

(Example) Next, the present invention will be explained according to illustrated embodiments.

The filtration system of the present invention is shown in FIG. In the same figure, 1
is a membrane sheet plate formed by covering a membrane support plate with a membrane, and a membrane unit 3 in which these sheets are stacked at a constant interval 2 is attached to a reciprocating support fitting 4.4°..., and a solution tank is used for filtration processing. 5, and filtration is performed by suction or pressurization while reciprocating the membrane unit 3. The reciprocating movement is not limited to the horizontal direction shown in the drawings, but may also be vertical. In the figure, 6 is a liquid collection pipe, 7
is a permeate extraction tube. Below, the constituent elements of the pressure plate type reciprocating filtration device according to the present invention will be explained in order.

The membrane support plate of the invention may be a flat plate. For example, it can be manufactured by covering a perforated plate made of sintered particles, a metal plate, or a plastic plate with a cloth or net that serves as a passage for the permeated fluid. However, the manufacturing process may become complicated, and the membrane support plate may become thick and heavy. As a membrane support plate, the membrane unit moves back and forth during filtration operation! ! It is preferable that the surface of the membrane support plate is uneven so that the solution at the interface is well stirred and filtration is promoted. The membrane support plate is provided with at least one collection port for the permeate fluid. The membrane support must also have a communicating permeate fluid channel groove that allows the fluid that has permeated the membrane to flow out to the liquid collection port. An example of such a membrane support plate is shown in FIG.

FIGS. 2(a), (b), and (c) are a plan view, a vertical cross-sectional view, and a cross-sectional view of the membrane support plate, respectively. 8 is a membrane support plate, 9 is a permeate fluid channel groove, 10 is a liquid collection port into which a permeate fluid collection pipe is inserted, and 11 is a packing pedestal with a smooth surface.

FIG. 3 is an enlarged view of part A of the membrane support plate in FIG. 2. 9
．． 9° is a permeate fluid flow path groove. This groove should be so narrow that when it is covered with a membrane and pressurized, the membrane will not sink into the groove due to the differential pressure, and should be several microns to several hundred microns wide. Note that the groove 9' is omitted in FIG. 2. Further, in FIG. 3, 12 indicates a convex portion (protrusion) on the membrane support plate, and 13 indicates a concave portion (trough). Difference (height) between the convex portion and the concave portion in the distance between the convex portion and the concave portion of the membrane support plate. The ratio is preferably 1 to 10 times. At this time, during the filtration operation, the fluidity of the solution at the membrane interface becomes particularly good, resulting in good filtration efficiency.

FIG. 4 is a plan view (a) and a cross-sectional view (b) of the vicinity of the liquid collection port of the membrane support plate 8. Liquid collection tubes are passed through the liquid collection port of the membrane sheet plate alternately with gaskets that also serve as spacers. When a membrane unit is formed by stacking membrane sheet plates, the gasket pedestal 11 near the liquid collection port is provided with a flow path 9 through which the fluid that has passed through the membrane can flow out to the liquid collection port without resistance, and is completely airtight. It has a smooth surface that allows it to be held securely. If the width of the narrow groove formed in the packing pedestal 11 is large so that the fluid that has passed through the membrane flows out to the liquid collection port 10, the membrane covering the groove may dig into the groove and airtightness may not be ensured. be. In such a case, complete airtightness can be achieved by covering the pedestal with a sheet approximately 100 g or more thick to form a communicating tube. A membrane support plate provided with such a communication tube can be easily molded by injection molding.

Note that the lighter and thinner the membrane support plate is, the better.Since strength is also required, if it is a flat plate with permeate flow channel grooves, it is recommended to use 1 to 2 membrane support plates.
A thickness of about 1 m is sufficient. In addition, in order to improve filtration efficiency, the thickness of the membrane support plate with an uneven surface is preferably 2 to 5 cm from the viewpoint of its strength and degree of unevenness.Also, the material of the membrane support plate should be lightweight and strong enough not to deform. It is desirable to use a material with heat resistance and chemical resistance, but in reality, the workability of the support plate and material cost must also be considered. Considering heat resistance, metals and ceramics are also considered. Sintered materials may be used in terms of light weight and water permeability. - Membrane materials include polyethylene, polypropylene, vinyl chloride, AB resin, polycarbonate, polyphenylene oxide, U-polymer, polyamide, polysulfone, polyethersulfone,
There are peaks, Teflon resin, etc.

FIG. 5 is a cross-sectional view of the membrane sheet plate 1 in which the membrane support plate 8 is covered with IfI 14. In the figure, 15 indicates the stock solution. When the membrane support plate 8 is covered with 1114, the membrane 14 is It does not adhere completely along the unevenness of the membrane support plate 8, but as shown in the figure, it is bridged to some extent along the unevenness of the membrane support plate 8, and the slight gap 16 formed between the membrane and the support plate allows the fluid permeating through the membrane to pass through the membrane. It is a flow path. In addition, the fluid that has permeated through the membrane and the membrane support plate surface is flowed into the nearby permeated fluid flow channel through porous areas formed in the thickness direction of the membrane and weak contact areas. do. When creating a membrane sheet plate by covering a membrane support plate with a membrane, there are methods of creating a bag with the active layer of the membrane facing up, inserting the membrane support plate into it, and then gluing and sealing the insertion opening. After folding a sheet-like membrane to cover the membrane support plate, the joining surface of the membrane and both ends of the membrane are joined, or by setting the membrane support plate between two membranes cut to a predetermined size, There is a way to heat seal the area all at once. Of course, the membrane supporting plate (membrane sheet plate) covered with the membrane must have a liquid collection port (water intake pipe insertion port). This hole may be made in a predetermined position in the membrane before covering the support plate with the membrane, or it may be made after covering the support plate with the membrane.

Cover the membrane support plate with a membrane and 115! When bonding the bonding surface or the surrounding area, there are two possible cases depending on the material of the membrane. If the membrane is made of one material, it can be easily done by overlapping the bonding surfaces and using heat fusion or an adhesive that is adhesive to the polymer. The second is a membrane that forms a semi-permeable membrane and a network made of a different material that reinforces it.

When the support sheet is made of cloth, non-woven fabric, etc., if the support sheet is simply overlapped and fused or bonded with an adhesive, the bonded surfaces may be different or in contact with each other and may peel off. The bonding method will be shown below with reference to FIGS. 6 and 7. Figure 6a
-1, when the membrane is formed only from the same material 14 and is not backed by a different reinforcing sheet, the joining surfaces 17 can be overlapped and bonded by fusion or adhesive suitable for the membrane material.

Figure 6a-2 is the same as Figure 6a-1, when the membranes are made of the same material, a bonding sheet 19 of tens to hundreds of microns made of the same material as the membrane is placed on top or bottom of the bonding surface of the membrane. It can be set on the holder and fused or adhered with an adhesive suitable for the material.

As shown in Fig. 6 b-1 and Fig. 6 b-2, the membrane is the material 14.
On the other hand, in the case of a membrane lined with a different material 18, as shown in the figure, when bonding from the surface of the membrane, set a bonding sheet 19 made of the same material as the membrane, and when bonding from the back side of the membrane, set the bonding sheet 19 on the membrane. A joining sheet 19 made of the same material as the reinforcing material can be set and bonded by fusion or adhesive. Furthermore, since various adhesive tapes have recently been developed, there are cases in which films can be sufficiently adhered to each other even when adhesive tape is used instead of the band-shaped joining sheet. A sketch of covering the membrane support is shown in FIG. Note that the liquid collection port is omitted in this figure.

Semipermeable membranes used in the present invention are mainly used for filtering fine particles, bacteria, etc., and precision membranes with pore sizes ranging from 100 to submicron, used for separating gas and liquid, and for filtrating colloidal particles. Targets include outer filtration membranes, reverse osmosis membranes that separate and filter solutes, and gas separation membranes that selectively separate gases. Membrane materials are acetylcellulose, chitosan, cellulose,
Examples include polyamide, polyimide, polyacrylonitrile, polysulfone, polyethersulfone, polyethylene, polypropylene, vinylidene fluoride, vinyl chloride, polyvinyl alcohol, and Teflon. There are also charged membranes and polyion complex membranes in which these materials have dissociative groups.

The membrane sheet plates and spacers produced as described above are stacked alternately, and a disk body is assembled in which the liquid collection port is penetrated by a liquid collection pipe and a female threaded hole is formed in contact with the outer surface of each of the top and bottom layers. By screwing into the liquid pipe or joining an appropriate stopper member, a membrane unit is produced in which separation of the laminated membrane sheets is prevented and the airtightness of the end-layered membrane sheets is maintained. This liquid collection tube may have the same shape as the liquid collection tube of the laminated sheet membrane previously filed (Japanese Patent Application No. 160623/1982). An example thereof is shown in FIG. 2 in the same figure
0 is a permeated fluid inlet hole formed in the wall of the liquid collecting pipe, and 21 is an outlet. The filtrated fluid passes through the permeate fluid channel groove of the membrane support plate and flows out to the liquid collection port in the packing pedestal, but the outlet of the channel groove leading to the liquid collection port is flush with the pipe wall of the inserted liquid collection tube. Since there is a risk that the flow path may be blocked due to contact with the liquid collecting pipe, it is preferable that the outer peripheral shape of the liquid collecting pipe is polygonal as shown in FIG.

In this way, the permeate fluid can once flow out into the gap between the membrane support plate and the liquid collection tube, and then flow into the tube without resistance through the hole in the liquid collection tube wall. As another method, a cylinder may be used as the liquid collection pipe, and a membrane support plate having a circumscribed polygonal hole may be used.

According to the present invention, if the spacing between the membrane sheets of the membrane unit is small, the fluid between them will be dragged by the reciprocating motion of the membrane unit, resulting in poor flow and extremely large concentration polarization during filtration, reducing filtration efficiency. Therefore, a certain amount of membrane sheet spacing is required, and its size depends on the membrane sheet surface structure,
It is determined by the viscosity of the solution, concentration of suspended matter or solution, stroke length of reciprocating motion, and number of reciprocating motions. Appropriate membrane sheet spacing is about 5 to 30 mm.

As another embodiment of the present invention to suppress concentration polarization at the membrane interface due to filtration, as shown in FIG. 10, the 3.3° membrane sheet plates of two membrane units are alternately combined, and one There is a system that improves the flow of the stock solution between the membrane support plates by fixing the membrane unit and reciprocating the other membrane unit, suppressing concentration polarization at the membrane interface that accompanies filtration as much as possible, and promoting filtration of both units. This filtration system is effective not only for filtering highly suspended and highly viscous solutions, but also as a biochemical reaction device. In other words, if one membrane unit is used as a stationary phase for bacterial cells or enzymes, and the other membrane unit is used as a filtration element to separate and recover metabolites or inhibitors, or to control substrates in the reaction tank, the reaction tank solution can be Constant stirring allows the biochemical reaction tank to be maintained in optimal conditions.

(Function) Efficient filtration can be achieved by fixing the membrane unit manufactured with the above-described configuration to a reciprocating shaft provided in a filtration tank and performing filtration while reciprocating. Although the liquid collection tube may be fixed to fix the membrane unit to the reciprocating shaft, as shown in Figure 1, fixing fittings are attached to the outer surfaces of the top and bottom layers of the membrane sheet plate to prevent the reciprocating motion. Can be fixed to the shaft. Since the membrane unit can be stably fixed with such fixing fittings, the size of the membrane sheet plate is, for example, 500 in width x 1000 in length.
■It is also possible to perform filtration using a large membrane unit that is the size of a dining table and is made up of multiple layers. Of course, considering the ease of handling the membrane unit, for example, the size of the membrane sheet plate is zoox 300 mm or 300 x 500 l.
Therefore, it is appropriate that the number of laminated layers is about 10 to 50 sheets. Filtration by the reciprocating motion of the membrane unit causes the solution to flow between the membrane sheets vigorously due to the periodic reversal of the direction of movement of the membrane unit and the uneven membrane surface, minimizing concentration polarization that reduces filtration efficiency, resulting in highly efficient filtration. enable.

(Effects of the Invention) Conventionally, tubular membrane modules and pressure plate modules have been mainly used to filter highly concentrated solutions, highly viscous solutions, and highly suspended solutions. Unlike the module, it is not necessary to send the stock solution to the module at a high flow rate, and by maintaining the membrane sheet plates at a constant interval, it is possible to handle the filtration treatment of solutions containing quite coarse suspended matter. In addition, in the module of the present invention, the membrane sheet plates can be adjusted to any desired spacing depending on the state of the raw water, so even if there is quite coarse suspended matter, no problem will occur in filtration.

Furthermore, in the filtration device according to the present invention, since the membrane sheet plate is simply moved back and forth within the filtration tank, the only energy loss is due to the flow of the raw water at the contact surface between the membrane surface and the raw water. This flow of raw water on the membrane surface is necessary for increasing the efficiency of any type of filtration. Therefore, the energy required for filtration by shaking the membrane unit in the present invention is mainly the energy required to flow the raw water on the membrane surface.

The filtration system according to the present invention can also be used as a biochemical reaction tank. For example, in an alcohol fermentation process using yeast, the concentration of alcohol increases as the fermentation progresses, weakening the activity of the yeast and reducing the rate of alcohol production. do.

When the filtration system of the present invention equipped with a hydrophobic membrane is installed in such an alcohol fermentation tank, the substrate is uniformly supplied throughout the tank by shaking the membrane unit, and raw and formed alcohols, which inhibit fermentation, are removed. It is vaporized and collected through a hydrophobic membrane, and the alcohol fermenter is always kept in the optimal condition.
Alcoholic fermentation can be carried out continuously. Not only when the products are volatile as in alcoholic fermentation, but also in biochemical reactions, changes in substrate concentration, increase in metabolite concentration, or accumulation of inhibitors occur as the reaction progresses, causing a decrease in reaction efficiency. However, by using this device, the biochemical reactions in the tank can be continuously optimized by constantly stirring the tank uniformly, and at the same time filtering the solution containing products while allowing bacteria and enzymes to remain in the tank. Can be held as it progresses. In addition, although Figure 1O shows a combination of a fixed membrane unit and a movable membrane unit, it is also possible to use one of these membrane units as a stationary phase for bacterial cells or enzymes, and use it as a device that efficiently performs biochemical reactions and separations at the same time. It is. In addition, in reactions involving gas generation, one membrane unit is equipped with a hydrophobic membrane to function as a gas permeation unit, and the other unit functions as a solution permeation unit, allowing the biochemical reaction tank to be maintained in an optimal state.

On the other hand, this device can also perform its function in filtering solutions containing highly concentrated suspended matter. In a solution containing from several thousand pp- to several percent suspended particles, as the solution is concentrated, the single particles of the suspended particles coagulate with each other to form a cake. Therefore, in filtration using existing membrane modules, flow path blockage often occurs, and the concentration limit must be kept low in many cases. For such concentration processing, the filtration system of the present invention can save energy and obtain a high degree of concentration.

Examples of such target liquids include metal surface treatment wastewater such as iron and aluminum, fine particle carbon suspension solutions, cheese whey solutions, and various fermentation solutions.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view of a filtration device according to an embodiment of the present invention, and FIG. Example plan view, longitudinal sectional view,
3 is an enlarged perspective view of part A of the membrane support plate in FIG. 2, FIGS. The figure is a cross-sectional view of the membrane sheet plate, Figure 6 is an explanatory diagram showing the method of adhering the membrane, Figure 7 is an explanatory diagram showing the state in which the membrane support is covered with the membrane, and Figure 8 is a perspective view of the liquid collecting pipe. FIG. 9 is a plan view of a membrane support plate to which a liquid collection tube is attached, and FIG. 10 is a perspective view of the main part of the other side of the filtration device of the present invention. Explanation of symbols 1...Membrane sheet plate, 2...Gap between membrane separation unit,
3... Membrane unit, 4.4''... Support metal fittings, 5...
- Solution tank, 6...Liquid collection pipe, 7...Takeout pipe. 8... Membrane support plate, 9... Permeate fluid channel groove, lO...
・Liquid collection port, 11... Backing pedestal, 12... Convex portion, 13... Concave portion, 14... Membrane, 15... Undiluted liquid patent applicant Kozo Iizuka, Director of the Agency of Industrial Science and Technology Figure 4 (a) Figure 8 Figure 9

Claims (1)

[Scope of Claims] 1. A membrane separation unit comprising a plurality of membrane support plates stacked at predetermined intervals and provided with permeate passages covered with semi-transparent membranes is reciprocally mounted in a processing tank. A pressure plate type reciprocating filtration device, characterized in that a permeated fluid is taken out by reciprocating movement of a membrane separation unit immersed in a processing tank. 2. One membrane separation unit is fixed in the processing tank, and the permeation is collected from both membrane separation units by reciprocating the movable membrane separation units arranged to alternately engage the membrane sheet plates of the fixed membrane separation unit. A fluid separation device characterized in that a fluid is taken out. 3. A membrane biochemical reaction device involving filtration using either the fixed membrane separation unit or the movable membrane separation unit according to claim 2 as a stationary phase for bacterial cells or enzymes. 4. A membrane support plate in which the surface of the membrane support has a wavy uneven shape, and the distance between the depression and the protrusion is 1 to 10 times the difference between the bottom of the depression and the top of the protrusion. 5. A claim in which the liquid collecting pipe that penetrates the membrane support plate is inscribed in the hole in the membrane support plate, and is polygonal so that a part of the inscription is inscribed, or the hole in the support plate is an irregular shape other than a circle. Membrane support plate of Section 4. 6. The membrane support plate according to claim 4, further comprising a convex surface that also serves as a packing so that the membrane sheet plates can be stacked at predetermined intervals. 7. The membrane support according to claim 4, wherein the membrane support plate has at least one liquid collection port, and a permeate fluid channel groove having a width of several tens to hundreds of microns is provided throughout the membrane support plate communicating with this port. Board.