DE1961163A1 - Membrane link - Google Patents

Description

A 119ο

Aqua-Chem., Inc o, 225 North. Grand Avenue, Waukesha,

Wisconsin (VoSt.A.)

"Membrane link"

Considerable effort has been made because of the increasing problems of water scarcity undertaken to find economical methods and devices for removing salt from sea water or for Purifying brackish water to develop. In this respect, the greatest success was achieved with the help of distillation processes or devices or with the aid of electrodialysis methods and devices. However, there is there is also considerable hope in the reverse osmosis process to make drinking water economically viable to establish ο

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To salt water or brackish water with the help of reverse osmosis To clean, the contaminated water is brought into contact with a semipermeable membrane and a pressure above the osmotic pressure of the contaminated Water subject At a typical concentration of salt in sea water, the osmotic one lies Pressure on the order of 350 psig and consequently a pressure differential must be above this amount P can be maintained across the membrane. In this relationship it is not uncommon to create a pressure differential on the order of about 1000 psig and consequently it can be seen that the membrane requires substantial support in order to prevent rupture among such to withstand substantial pressures.

So far, the entire area of a membrane, whether flat or tubular, has been exposed to the non-pure water Druok was exposed, with the help of the wall of a pressure vessel, which supported the existing high pressures can withstand · Depending on the design of the membrane, such a wall can be in the form of a plate or of a pipe, but in any case this wall is of sufficient thickness according to its particular Geometry designed to withstand the extremely high pressures that occur in the reverse osmosis process. As a result, the cleaning device had to be made bulky using reverse osmosis and still required the use of a large one Amount of material that is resistant to high pressures to create pressure vessel walls of sufficient strength to create which can withstand high pressures.

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The first factor gives rise to demands for a large space and so near a relatively high capital investment, while duroh the last factor for an investment required capital investment is similarly increased because of the relatively large amount of required Material that withstands high pressures *

With the help of the invention, in principle, the cost of the equipment used for reverse osmosis processes is reduced, firstly by reducing the size of a unit which has a given capacity and secondly by reducing the amount of material required, which is resistant to high Pressure is when making a support for a membrane structure. The invention accomplishes both objectives duroh use of two or more contacting membrane cells in a device to support itself when a balanced pressure applied to both cells _# w ill. To maintain the pressure difference required for reverse osmosis, a very thin layer of porous material is placed between the membranes of two adjacent cells, and the pure water passing through the respective membranes passes through the pores of the porous material to be collected

In an exemplary embodiment, a plurality of membrane cells are provided and each has a cross-section generally the shape of a tottee. The membrane cells are arranged in a circle to form a cylindrical shape and a porous core is provided around the narrow ends of each membrane cell segment to support. The porous core has a central opening from which purified water can be collected for other

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schilessenden use can be taken · you Surfaces of the large ends of the membrane cell segments are of any suitable, non-perforated Material trimmed, which in any suitable way, for example by coating with fiberglass and resin can be reinforced · As a result, only the core and outer support need be formed to withstand the high pressures normally encountered in reverse osmosis processes with a support for the membranes on the side of each pie-shaped segment through the adjacent pie-shaped membrane cell segment provided is which is to be handled under substantially the same pressure.

The space and material requirements - can be reduced to about 1/3 of a conventionally designed device for reverse osmosis, which has the same ability to purify water.

Accordingly, one object of the invention is a membrane member for use in purification or concentration of contaminated liquids with the help of reverse osmosis, which is a number of tubular membranes having a generally pie-shaped cross-section, the membranes being made of one material are, which is impermeable to the contaminated liquid and are arranged in a generally circular configuration, the longitudinal sides of a each membrane essentially on the long sides of the other membranes rest, with a thin, porous sheet, which the pressures above the osmotic

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Not withstanding the pressure of the contaminated liquid is arranged between adjacent longitudinal sides of adjacent membranes and a passage for through the Membrane penetrating pure liquid is limited, whereby a core, which the pressures above the osmotic pressure can withstand the contaminated liquid, is located in the center of the circular formation and the narrow ends of each membrane is supported, with a housing that allows the pressures above the osmotic Can withstand the pressure of the contaminated liquid, the circular formation surrounds and the big ends of each membrane carries, and wherein a conduit means communicates with the porous sheet to receive the purified liquid and form one To lead assembly point.

Fig «1 is a cross section of a membrane member according to Invention,

Fig. 2 is an enlarged partial view of the diaphragm member;

Fig. 3 shows schematically how the membrane member can be used in series flow,

Fig. 4 shows schematically how the membrane member can be used with parallel flow.

An embodiment of the membrane member 1o according to the invention is shown in cross section in Fig. 1, and it has an outer housing 12 made of impermeable material.

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The outer housing 12 can be made of one material and have a bead which is sufficient, the normal To withstand working pressures in reverse osmosis units, which are greater than the osmotic pressure of the to cleaning liquid or, if used for concentration purposes, are larger than the osmotic liquid Pressure of the liquid mixture including solution), which one to focus on.

TJm to stiffen the outer housing 12, can around his P circumference wound a number of fiberglass strands 14 impregnated with any suitable resin are to hold them in place · The fiberglass and resin techniques are well known and do not need to be detailed to be dealt with

The inner surface of the outer housing 12 has a number of irregularities 16, which are shown in FIG Embodiment a substantially circular Training habenβ Within the membrane member 1o, a core 2o is centrally arranged, which consists of a Thickness and is made of a material such that it can withstand the normal working pressures in reverse osmosis processes. The core 2o is designed and can withstand pressures which are greater than the osmotic pressure of the liquid to be treated are ο

A bore 22 is provided centrally within the core 2o, which serves as a collecting space for the purified liquid, which with the help of the reverse osmosis process is obtained or for the liquid which the membrane

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structures can penetrate, which in detail still is explained below when the device is used for concentration purposes.

The core 2o has a number of irregularities 24 on its outer surface, as shown in FIG Embodiment have a substantially circular shape. Every irregularity is with surveys 26 connected, and in one embodiment, the small bores 28, the points 26 with the bore 22 connect · The core 2o can also be made of a porous material, in which case the bores 28 are not necessary.

You number of irregularities 24 in the core 2o and the number of irregularities 26 in the outer Housings 12 are the same and each serve to support the respective ends of a membrane cell structure.

They are generally designated with 3o membrane cell structures essentially have a pie-shaped shape

Cross-section, its generally circular

large ends each with a corresponding irregularity 16 received in the outer housing 12 and thereof are supported, and with the generally circular, small volumes of a corresponding irregularity 24 can be picked up and worn. The long sides of each membrane structure 3o are in essentially on the longitudinal sides of the neighboring membrane cell structure 3o to »

Each membrane cell structure has a thin porous sheet 32, which the adjacent long sides of the

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adjacent membrane cell, oil structure separates from each other and which delimits a flow path for water penetrating through the membrane to the core 2o, where it is through the holes 28 to the central hole for the purpose of collection or through the forums of the core 2o flows when the latter is made of porous material.

In Pig. 2 it can be seen that each membrane structure has an inner film-like wall 34 which consists of "consists of a material that is suitable for the Liquid or the liquid in a liquid mixture to be concentrated is semipermeable is. As is known in the art, such membrane films 34 normally included as a major component Cellulose acetate and thus chemically bound water.

The thin porous sheet 32 surrounds the membrane film 34 in the shape of a tube and can be made of any suitable porous material such as paper or porous plastics.

The membrane film 34 is poured onto the inner surface of the porous sheet 32, which is in the shape of a tube, using conventional methods

In one embodiment of the invention that can outer housing 12, the core 2o and the membrane structures 3o formed separately and by a suitable Orienting the core 2o with respect to the housing 12

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can be produced so that the membrane structure 3o can be arranged between the core 2o and the housing 12. If other extrusion methods are used, the core 2o and the thin sheet 3ο of a porous material can be extruded simultaneously with the extrusion of the impermeable, non-porous, outer housing 12, so that a uniform structure is formed.In such cases, after the unitary member has been formed, the Membrane film 34 can be cast on the thin porous sheets 32 in the similar manner as mentioned above.

From the foregoing it can be seen that the presence of the thin porous sheet 32, which is in the form of a tube surrounding the dissimilar membrane, creates a flow path around the entire periphery of the film-like membrane wall 34 so that water which diffuses therethrough to the core 2o to be collected in the bore 22 · As a result, the entirety of the surface of the membrane 34 is used.

Because in the embodiment, each membrane cell structure 3o with a tubular thin, porous Sheet 32 is provided at each interface, two layers of the thin porous sheet 32 are provided. However, when using the extrusion method mentioned above only one such layer needs to be present. The only requirement for the thin porous Sheet 32 is that it has to be somewhat rigid to aid installation, that it is porous is to create the desired flow path and that

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it is of such a nature that the pores eioh Do not close if you have the working pressure of a Reverse osmosis unit are subjected. They mentioned above materials, namely paper and porous Plastics that meet these requirements · It is also important to have a very small thickness for the thin porous sheet 32 required is a fraction of 1 cm · For example, is a wall thickness of approximately 0.4 ma satisfactory

If substantially the same pressures are applied in each of the membrane cells 3o, and if their long side is in alignment with the long side of the neighboring cells As is membranes, the relatively thin walls which divide the cells will be substantially the same and subject to opposing balancing forces on opposite sides, so that any tendency to Break off is · Sa the vast majority along the membrane surface of each cell Longitudinal walls is, which in known devices would require substantial reinforcement withstanding the high pressures which generally occur becomes a substantial saving in quantity of the material required to withstand high pressure «Similarly, the entire membrane structure 1o, because a lot of the material that has to withstand high pressure and earlier in the known structures used, is omitted, of considerably smaller size than corresponding ones known devices and then work under the same conditions to get the same amount of purified Generate liquid within a given time,

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Furthermore, the design of the rope is such that it can easily be adapted to any desired flow path. In Fig. 3 it is shown schematically how the part 1o can be used to create a series flow path EU create · part 1o ends are through caps 4o and 42 closed, each having a plurality of reverse channels 44- to the liquid, which flows through each membrane cell in an opposite direction to the adjacent membrane cell conduct·

The end caps 4o and 42 can be on the membrane member 1o can be attached using any two-dimensional device, and the channels 44 can be connected to the corresponding Membrane cells 3o are sealed

In addition, the end cap 4o has a channel 46 which communicates with the bore 22 in the core stands so that the liquid penetrating the membranes 34 can be guided to a point of use. In a similar way, the end cap 42 includes a first channel 48, which with one of the membrane cells 3 o is in connection and through which the input liquid can be fed · Finally, there is a second Channel 5o is provided on the end cap 42, from which the concentrated liquid can be drawn off

Another arrangement is shown in FIG Membrane member 1o with parallel flow of the liquid Can be used · Again, the ends of the

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Membrane member 1o duroh end caps 52 and 54 sealed, the cap 52 having a number of interconnected channels 56 connected to one end · one each membrane cell 3o are in communication. A channel 58 connects the channels 56 so that the icons are entred Liquid can be drawn off End cap 52 provided with an outlet channel 6o, from which the liquid can be collected, which duroh flows through the membranes.

The end cap 54 has a channel inlet 62 in which the liquid can be introduced into, and this channel is in a multitude of interconnected Communicating channels 64- which communicate with the other end of each membrane cell Jo stand in order to direct the liquid into each cell

It can be seen that the membrane member 1o according to the invention in both series and parallel flow devices can be used. Of course, a single piece 10 can be used in both series and parallel flow paths if so desired. Appropriate modifications of the channels within the end caps can be made be carried out by a specialist

The invention is described in connection with What β he cleaning, but it will be apparent to those skilled in the art that it can also be used for other cleaning or concentration processes

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Patent claims e

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Claims (1)

Claims Membrane member for use in cleaning or concentrating contaminated liquids with Aid of reverse osmosis, characterized by a number of tubular membranes (34) essentially pie-shaped cross-section, the membranes are made of a material suitable for the contaminated Liquid is semi-permeable and arranged essentially in a circular configuration, the long sides of each membrane essentially abutting the long sides of the other membranes, through a thin porous sheet (32) which is incapable of pushing above osmotic pressure to withstand the contaminated liquid, which is between the adjacent long sides of adjacent membranes is arranged and delimits a flow path for the purified liquid which the membranes penetrates, through a core (2o), which pressures above the osmotic pressure of the contaminated Can withstand liquid and is located in the center of the circular formation and the narrow Ends of each membrane carries, through a housing (12), which pressures above the osmotic pressure of the can withstand contaminated liquid and the circular formation surrounds and the large ends each membrane carries, and by a conduit means (22,28), which is in connection with the porous sheet in order to take up liquid purified from there and direct them to a collection point. -14-009823 / 1695 -U- 2o) membrane member according to claim 1, characterized in that that the porous sheets (32) the small and large ends of each tubular membrane (34) that the core (2o) is perforated and the housing (12) is not perforated and that the conduit means the perforation (28) in the Core and a bore (22) located substantially centrally therein. ™ 3 ·) Membrane member according to claim 2, characterized in that that the porous leaves (32) are tubular and have a substantially pie-shaped cross-section have, which corresponds to the cross section of the membranes (34), and that the membranes with the porous Scrolls are connected. 4) Membrane member according to claim 3, characterized in that that the inner surface of the housing (12) encloses a multiplicity of clock-rule leaks (16), one for each membrane, each irregularity having a shape that corresponds to the shape of the large one End of the corresponding membrane and porous sheet corresponds to and engages with the corresponding porous sheet is. 5 ·) membrane member according to claim 3 or 4 »characterized in that the outer surface of the core (2o) a Including plurality of clock regularities (24), one for each membrane, each irregularity has a shape corresponding to the shape of the narrow end of the corresponding membrane and the porous sheet and engages the corresponding porous sheet. 009823/1695