DE29624474U1 - Multi-component liquid micro-filtration apparatus with surface cleaning - has vertical skeins formed of a number of equal length hollow fibres each end held in headers where air discharged at skein base produces bubbles in quantity large enough to scrub the fibres. - Google Patents

Abstract

A micro-filtration appts. has first and second headers vertically spaced apart at a fixed distance, the lower within the liq. substrate. Each header securely holds one end of a number of hollow fibre membranes each of equal length which is 0.1 to 5% greater than the length between the headers permitting restricted movement of the central fibre portion independent of the movement of another fibre which are subjected to transmembrane pressure differential in the range 0.1 to 50 psi. Also claimed are: (i) permeate collecting means sealing connected in fluid communication with permeate discharge face of each header and a means to withdraw the permeate; (ii) gas scrubbing assembly; (iii) process for maintaining the outer surfaces of the membranes free from build-up; (iv) method of forming a skein; and (v) a header having potted hollow fibre membranes.

Description

The present invention relates to a membrane device that is an improvement over a frameless Representing array of hollow fiber membranes. The one used in the title Expression "vertical strand" (hereinafter the For brevity called "strand") focus in particular on an integrated combination of structural elements, including (i) a plurality of vertical fibers of substantially the same length; (Ii) two head elements, in the opposite connection areas the fibers are cast in to keep the ends open; and (iii) a permeate collector, those on the periphery in liquid-tight Engagement with each head element is kept to permeate from the Catch the ends of the fibers. Those used in the main filing expressions are summarized in the glossary contained herein.

The present invention relates to especially relatively large ones Systems for microfiltering liquids and sets great Emphasis on the simplicity and efficiency of a configuration the on the manufacture of a module in which the fibers are trapped are waived. As with U.S. Patent No. 5,248,424 in the novel configuration air that is close to the base part of a Strangs emerges in an efficient way to create bubbles in a specific size range and in an amount sufficient to wash the fiber and Effecting a controlled scrubbing of the fibers against each other ("inter-fiber washing"). Different than that in the '424 patent described system, the fibers run vertically in one strand and have no arcuate Configuration via a horizontal plane through the horizontal center line of a Head element. Consequently runs the path of the ascending bubbles is essentially parallel to the Fibers and is not crossed by the fibers of a vertical strand. However, the bubbles wash the fibers.

The limited moving back and forth Fibers do not get tangled due to their defined length and do not abrade one another, as described in the '424 patent Array is likely. The one going from side to side Displacement of an intermediate area of each fiber within the "restriction zone" or "bubble zone" is restricted by the fiber length. The length defined here the fibers minimize (i) shear forces, if the top fibers are held in the top header, (ii) excessive rotation the top of the fibers and (iii) excessive wear between the fibers. Such a reciprocation of a fiber with a shift from one side to another is different from a vibration, that occurs when a fiber is tensioned, i.e. H. if the length of the cast fiber exposed to the substrate is not larger than the distance between the opposite sides of the Upper and lower head elements holding fibers. Such a vibration will according to the US patent No. 5,209,852 to Sunaoka et al in a splitting process and deposition of dense particles induced by bubbles. Different to for fibers that according to the im Process described in the '852 patent are held in the module with our new strand no tension in each fiber since the opposite Sides of the header elements by a distance that is less than the length of one single fiber, are spaced apart.

The use of an array of fibers in the direct treatment of an activated sludge in one Bioreactor is described in an article entitled "Direct Solid-Liquid Separation Using Hollow Fiber Membrane in an Activated Sludge Aeration Tank "by Kazuo Yamamoto et al in Wat. Sci. Tech., Vol. 21, Brighton, pp. 43-54, 1989, and described in the '424 patent, and the description is included by reference as if it were complete here listed. The relatively poor performance that Yamamoto et al achieved was mainly due to the fact that the importance of maintaining one has not been recognized Electricity by supplying a fiber strand with air from within and is below the strand. It has not been recognized that it is necessary to use essentially the entire area flowing through the strand Wash bubbles to keep the fibers flooded with bubbles. This Requirement becomes more important when the number of fibers in the Strand rises.

Tests conducted on the Yamamoto et al device show that if the air is provided outside the string, the current will decrease much faster over a period of only 50 hours, confirming the results achieved by Yamamoto. This goes out 1 which is described in more detail below and in which the graphs show results achieved by Yamamoto et al and with the array described in the '424 patent and with a vertical strand in which the headers are rectangular, in which identical fibers were used under essentially identical conditions in all three arrangements.

The down-hanging fiber study by Yamamoto et al continued, and recent developments were described in an article entitled "Organic Stabilization and Nitrogen Removal in Membrane Separation Bioreactor for Domestic Wastewater Treatment" by C. Chiemchaisri et al Discussion at the Conference on Membrane Technology in Wastewater Management in Cape Town, South Africa, held on March 2-5, 1992 and also described in the '424 patent. The fibers were hung down and it was highly turbulent water in alternating directions electricity important.

It is obvious that the description in the reference of both Yamamoto et al and Chiemchaisri et al has shown that the air flow over the surfaces of the hanging fibers has little or nothing helped the attachment of microorganisms to the substrate to inhibit.

It was later attempted in Yamamori et al. European Patent Application 0 598 909 A1 to avoid the problem of buildup on the fibers by "spreading the hollow fibers in the form of a flat sheet" (see page 4, lines 46-47), and so on gives no indication of how the fibers are held in a spread position when actually used. Furthermore, each array is held in a "structural element for enclosing and holding the fastener" (see page 3, line 42 and lines 51-52), which is contrary to the concept of a frameless array. 14 and 18 highlight the horizontal configuration in which the array is used. Regarding fighting construction shows 13 how the fibers would form troughs if the array were removed from the vibrating or shaking container. A module corresponding to the state of the art is in 16 shown, in which both ends of each fiber are cast into a cylindrical head element, each fiber forming a loop and the ends formed to the loop are free. According to the in 17 Data listed below was less effective than the use of the prior art cylindrical module in which the looped ends were free to move in the substrate 1 shown frameless array with spread fibers formed into loops.

It has been found that for no known reason, fibers longer than 5% but less than 10% longer than the fixed distance between the opposite sides of the headers of a vertical strand tended to shear on the side; and the 10% longer ones tended to clump in the bladder zone; and that a gas scrubbed vertical strand with limited reciprocating fibers provides an optimal configuration of the fibers by blowing a fiber cleaning gas ("scrubbing gas") when they flowed vertically upward, parallel to and along the fiber surfaces. With a strand of any desired area in the range of about 0.1 m ² to 1000 m ² or more formed by densely packed fibers, bubbles in such a configuration are more effective detergents than bubbles made from arcuate fibers which form the Cross the path of the rising bubbles, be caught. A comparison is made between strands with different fiber orientations. Bubbles of an oxygen-containing gas to promote the growth of microbes unexpectedly fail to cause microbes to grow on the surfaces of the reciprocating fibers because the surfaces are "vertically air-washed". Deposits of living and / or non-living particles on the fiber surfaces are minimized if the fibers, which can be moved back and forth, are kept flooded with bubbles rising in the same direction, which rise at a rate sufficient to achieve a physical washing power (the motive power provides the Energy) with which the fibers are kept essentially free of harmful deposits. Thus, an unexpectedly large current is maintained in the fibers over each area of the strand fiber area for a long period of time.

In a "gas-washed arrangement" with one strand and a gas distribution device, the strand fibers in each other spaced headers so that the fibers when they are inserted into the substrate, a substantially vertical one Accept profile in the substrate and in that of at least one bubble column formed bladder zone independently move back and forth from each other. The fiber length between opposite one another surfaces of head elements from which they protrude lies in a critical one Area where it is at least 0.1% (percent) but less than Is 5% larger than the distance between these opposite sides. Usually is the length the fibers are less than 2% larger, in most typical case is less than 1% larger, so the back and forth movement the fibers are restricted within a vertical movement zone, the periphery of this zone from movement of the outer strand fibers is defined from side to side; and the majority of these Fibers moves in a zone that is slightly larger than that zone which is defined by an area that a header element points to others projected. Although the distance between the head elements while operation is fixed, the distance is preferably adjustable, for an optimal fiber length within the aforementioned areas between the head elements produce.

For commercial wastewater treatment of all kinds are the strands typically in the range of 30 m2 to 500 m2; in other specific Applications, such as B. in water treatment in one for leisure purposes used vehicle, an aquarium for aquatic animals or for manufacturing a solid-free sample of a fluid for analysis purposes a strand with a much smaller area from 0.1 m2 to 5 m2, which is referred to as an "independent mini-strand", with its own gas supply facility and permeate extraction pump educated.

Permeate can only be taken from one, usually the upper, permeate collection device (trough or end cap), or for strands with a large surface area of more than 200 m2 from both (upper and lower) troughs or end caps. In the most preferred variant, air is blown from one in one of several configurations cast an air tube between strand fibers, depending on the configuration of the head element in the strand or the configuration of several head elements in a group of strands. Preferably, the air tube provides air to an injection tube near the base of the strand fibers and at the same time forms a spacer for positioning and spacing the lower header at the required distance from the upper header. The injection pipe is part of a gas supply device that supplies cleaning gas.

A new type of composite head element is for a bundle of hollow fiber membranes or "fibers" provided where the composite head element has a molded laminated body has any shape, which is an upper lamination of a "fixing" (casting) material has that with a lower lamination of a "volatile" casting material is laminated. The connection areas of the fibers are in the volatile casting material poured in if this is liquid , preferably a substantially rectangular parallelepiped (Cuboid) is formed, in which the open ends of the fibers (bis for pouring) are embedded and plugged in, which keeps the fibers close together be held substantially parallel to each other. The plugged in The ends of the fibers do not protrude the lower (rear) side of the lower laminating agent, while the remaining lengths of fibers run through the top of the lower lamination. The top lamination runs over a Height along the length of fibers sufficient to space the fibers at a distance from each other to maintain the same spacing in the lower area. If desired the composite head element can be additional Have laminating agents, e.g. B. a "cushion" lamination over the fixing lamination to cushion each fiber around its embedded outer circumference; and a "sealant" lamination as suitable sealing material on which the permeate collecting device can be grown.

Although any for the head element Shape chosen each head element is one for easier production Pairs either as a rectangular parallelepiped (cuboid) or cylindrical Disc formed. Rectangular vertical fibers become rectangular Cast head elements; cylindrical vertical fibers are in cast cylindrical head elements. For maximum use of space in a head element the fibers are densely arranged in rows or in a spiral Rolling up a big one Arrays to spiral Rolls packed with each end of the spiral roll directly into one cylindrical resin sealing device is poured. Such Resin sealing device is typically rectangular or cylindrical trough or end cap. Both header configurations can in a variety of different embodiments, as shown in the explanatory Examples are used.

U.S. Patent No. 3,730,959 a head element and permeate collection device according to the preamble of claim 1, which for Pressure hull systems useful and in which the fibers are sealed by an epoxy resin are a section of a stainless steel tube that goes through into a longer tube a pressure seat is installed.

SUMMARY THE INVENTION

It is the object of the invention to create a head element and permeate interception device that is simple to manufacture.

This task is accomplished by a head element and permeate interception device according to protection claim 1 solved.

The present invention provides a head element and permeate collection device, the cast Contains hollow fiber membranes, the head element and permeate interception device having the following features:

• a) a solid mass made of a casting material, the first surface having;
• b) a plurality of hollow fiber membranes in the molding material are included; and
• c) end sections of the hollow fiber membranes, the end sections are adjacent to open ends of the membranes and from the first area project, whereby
• d) the solid mass of casting material to the inner Periphery of the permeate catcher extends and adheres to the same is attached to form a permeate collection zone; and
• e) the end sections with the open end of the hollow fiber membranes protrude into the permeate collection zone.

The head element preferably comprises the one dampening Layer that embeds the fibers, with the cushioning layer on the molding material sticks and covers the same. The damping layer preferably has a hardship in the range from Shore A 30 to Shore D 45

BRIEF DESCRIPTION

The above and other objects and advantages of the invention are best understood from the following detailed description and the schematic representations of preferred embodiments of the invention in which the same reference numerals designate elements. Show it:

1 a graphical representation in which the change in current is plotted as a function of time, showing three curves for three runs with three different arrays, in each case using the same amount of air, identical membranes and the same membrane surface area. The results obtained by Yamamoto et al are as a curve 2 (under modified conditions to account for issues in question regarding the test procedure used, as explained below); the current achieved with the gas-washed arrangement of the '424 patent is as a curve 1 shown; and the current achieved with the gas-washed arrangement according to the invention is as a curve 3 shown;

2 an exploded perspective view in which a membrane device with strand fibers, which are not held between the head elements and are not connected to one another, is shown schematically, the fiber ends being cast into a lower head element, which is shown during operation of the device, with a permeate collecting trough and a permeate extraction line;

2A an enlarged side view of a section of a side wall of a drip pan showing the profile of a head element retaining step on the periphery of the tub;

2 B a bottom view of the head member showing any pattern of open ends protruding from the rear of a head member when fibers are poured in after being stacked in rows and glued together before pouring;

3 a perspective view of a schematically illustrated single array of a series of substantially coplanar parallel fibers which are attached near their mutually opposite terminal ends between spaced cards. Typically, multiple arrays are assembled before being sequentially cast;

4 an end view of a stack of arrays clamped together, showing that the individual fibers (only the last fiber of each linear array is visible, the remaining fibers in the array are immediately behind the last fiber) of each array by the thickness of one with an adhesive provided strip are spaced from each other when the stack is held vertically in the casting liquid;

5 a perspective view with a schematic representation of a strand with its finished head element, its permeate sump and double air tubes, which are all formed in one piece with the strand, the double air tubes being an integral air distribution line cast into the head element along an outer edge of the strand fibers supply;

6 a side view of a finished one-piece head member showing details of a permeate tub immersed in the substrate, the head member walls resting on the lower part of a container and supplying a plurality of air tubes integrally molded air distribution conduit molded along each outer edge of the strand fibers;

7A a perspective view with a schematic representation of an air manifold from which vertical air pipes rise;

7B a perspective view with a schematic representation of a tubular air manifold with a transverse perforated area which is positioned by mutually opposite connection areas;

8th a perspective view of a finished integrally formed head element with a plurality of strands cast into a common head element, which is molded into an integrally molded permeate collecting device, from the air pipes between adjacent strands and along the outer periphery of the outer strands rise vertically from the head element;

9 an out-of-scale section of a gas distribution device that directs gas between the arrays in a header and optionally along the sides of the lower header;

10 a perspective view with a schematic representation of two strands in a group, the upper head elements are attached with their ends to the vertical wall of a tank. The strands, together with a gas distribution device, form a "gas washing arrangement" which is inserted into the substrate, the fibers hanging essentially vertically in the substrate. By positioning the gas washer between the lower head members (and optionally on the outside of the strand fibers), masses (or "pillars") of bubbles are created that rise vertically in the same direction as the fibers, the bubbles washing the outer surfaces of the fibers;

11 a perspective view of another embodiment of the washing arrangement showing a plurality of strands (only two of which are shown) which are connected in series, a gas distribution device being arranged between successive strands and optionally a further gas distribution device being provided in front of and behind the first or last strands is;

12 a side view with a schematic representation of a group of strands that are attached to the wall of a bioreactor, with all pipe connections are outside the liquid;

13 a top view of the in 12 The bioreactor shown, in which it is shown how several groups of strands can be positioned around the periphery of the bioreactor to allow large permeate removal ne to form, while in the central area a clarification zone is formed from baffles;

14 a cross section with a schematic representation of a cylindrical strand with integrally formed with the end caps upper and lower head elements, each having a fiber array is poured directly into a finished head element, which is sealed at its periphery against the wall of the end cap without a seal;

14A a bottom view of a cast-in array held as a roll in a fiber insert mold before the end of the roll is cast in a ring to form a one-piece header in which the fiber pattern is spiral;

14B a bottom view of a series of cast cylindrical arrays called "ring arrays" since the ends are fixed in rigid cylindrical rings, the arrays being interleaved with each subsequent ring array that is slid over the previous one. These nested rings are then poured into a resin sealing ring;

14C a bottom view of a series of planar arrays, the width of which is selected such that they can be stacked in a strand (ie as successive strands in the resin sealing ring) before the stack is poured into the ring;

15 a cross section with a schematic representation of a cylindrical strand and integrally formed with the end caps head elements, as in 14 shown, with the exception that permeate is only taken from the top header;

15A a perspective view of a cross-shaped injection tube with a centrally arranged air tube and injection arms;

16 a side view with a schematic representation of a cylindrical strand, in which an annular head element is first formed. The ring-shaped head element is then enclosed by an end cap. In addition to the permeate pipe, a rigid air supply pipe is inserted through the upper end cap and the upper head element into the central region of the strand, the lower part of the air supply pipe being cast into the lower head element and thus serving as a spacer and at the same time as a holder for the upper end cap;

17 is a schematic representation of a further embodiment of the strand, in which the permeate tube is arranged concentrically in the air supply tube and both are cast near the lower ends in the lower head element. Ports in the lower end of the air supply tube deliver air near the base part of the strand fibers;

18 a bar graph showing the average current over a period of 24 hours for each of the three different orientations of the strand;

19 a graphical representation of the current as a function of the time until the current reaches an equilibrium value for the same line with internal and external air supply;

20 a graphical representation of the current as a function of the time until the current reaches an equilibrium value, namely for strands with an identical area, with the exception that the fibers are once tensioned and once relaxed.

DETAILED DESCRIPTION PREFERRED EMBODIMENTS

Vertical strand and arrays that form this: the strand according to the invention is used in liquid-liquid microfiltration processes for removing solid suspended matter in the micron, submicron and larger area, such as B. organic molecules, emulsified organic liquids and colloidal or suspended matter, usually used in water. Typical areas of application include (i) in a membrane bioreactor to produce permeate as purified water; (ii) filtering secondary Wastewater from wastewater treatment to remove solid suspended matter and pathogenic bacteria; (iii) Clarifying water flows to the Manufacture of drinking water (removal of colloids, long chain carboxylic acids and Pathogens); (iv) depositing a permeable liquid component in biotechnical nutrient solutions; (v) dewatering of metal hydroxide slurries; and (vi) filtering oily Sewage.

Typically, the strand is like this configured that all Connections for Fluids entering or leaving the strand in the upper head element are provided. Permeate is the most preferred Variant taken through a tube running through the upper head element, if (i) the lower header does not collect permeate (like explained below); or (ii) permeate is found in both the upper and lower Head element accumulates. The strand preferably works in one Substrate that is in a container with atmospheric Pressure (1 bar) or above located in a pressure range up to about 10 bar Vessel without in the housing of a module to be.

One or more arrays are in header elements encapsulated, their upper (or "front") and lower (or "rear") surfaces in horizontal (x-y) planes. Instead of a single continuous Arrays are made up of multiple arrays and are consecutive at the ends connected together to form a much larger array that is expandable.

The operation of the line is through (α) the selected one Fiber, (b) the amount of air used, and (c) that to be filtered Influenced substrate. The goal is to filter yourself out slowly moving or held substrate in a large container underneath Ambient or elevated Pressure, but preferably essentially under ambient pressure, and maximizing the efficiency of this one (the filtering) practical and economical Way performing Train.

By operating at ambient pressure, installing the one-story trained head elements of the strand in a container of Substrate and enabling a restricted Movement of the fibers in the bubble zone in a substrate becomes one damage of fibers minimized. Since at least 10, preferably in a head element of 50 to 50,000 fibers are held, each in the is essentially at least 0.5 m long, is in one strand greater area for the Filtering the substrate provided.

Fibers and like this dense are packed:

The fibers divide a container a "feed zone" and a removal zone, which is referred to as the "permeate zone". The inflow of substrate occurs outside (as "from outside to inside " Stream) of the fibers, and the substrate splits into "permeate" and "concentrate" streams. The strand according to the invention or a group of strands of the invention is most preferred Variant for the Microfiltration with "von Outside inside " Electricity used. Although at least one strand is interchangeable in one small container with a volume of up to approximately 10 l (liters) and even up to about too 100 l or more is arranged, a group of strands is preferred in a relatively large container with a volume of more than 1000 l, such as. B. a flowing watercourse or more typically a pond or tank. In the most typical variant will be one group or several groups of reception facilities for the permeate into a big one Tank with atmospheric Pressure installed and permeate is removed from the tank.

The used to make the strand Fibers can from a conventional Membrane material must be made, provided that the fibers are flexible are and one for the microfiltration average pore diameter have, namely in the range of approximately 1000 Å to 10000 Å. Typically, the fibers are 1 m to about 5 m long, depending on the dimensions of the substrate body (Depth and width) in which the strand is inserted. preferred Fibers work in the area at a transmembrane differential pressure from 7 kPa (1 psi) - 69 kPa (10 psi) and are at ambient pressure, with the permeate below Gravity is removed. These fibers will be from the point of view of the desired Function selected, and the dimensions of the strand are determined by the geometry of the head elements and the length of fibers determined. It is unnecessary, restrict a fiber in a modular housing, and this is also not the case.

With hollow fiber membranes, the outer diameter is ("AD") of a fiber at least 20 μm and can until about Be 3 mm it is typically in the range of approximately 0.1 mm to 2 mm. The bigger the AD, the less desirable is the area ratio per Volume unit of the fiber. The fiber wall thickness is at least 5 μm and can be up to 1.2 mm in size, it typically ranges from about 15% to about 60% the AD of the fiber and in the most preferred variant in the range from 0.5 mm to 1.2 mm.

Any number of fibers can be present in a single array, typically the number ranges from about 1000 to about 10,000 for commercial applications, and the preferred area for a strand is at least> 1 m ² , typically from 10 m ² to 100 m ² . The center distance of adjacent fibers is preferably 1.2- (1.2d) to about 5 times (5d) the AD 'd' of a fiber. A preferred center spacing is between about 1.5d and 2d. The packing density of fibers, ie the number of fibers per unit area of a head element, is preferably in the range from 4 to 50 fibers / cm ² , depending on the fiber diameter.

The special method of fastening the fibers in each head element is not critical, the choice depends on the materials of the head element and the fiber as well as the costs for the Use a different process than pouring. However, it is important that each fiber is fluid-tightly attached to each head member is to avoid contamination of the permeate. this happens by essentially vertical, closely spaced and essentially concentric pouring of the fibers.

Preferred fibers are made from organic polymers and ceramics, they are isotropic or anisotropic and have a thin layer or "skin" on the outer surface of the fibers. The fibers can be made from braided yarn with a cover made of water-insoluble polymer material, as described in US Patent No. 5,472,607. Preferred organic polymers for fibers are polysulfones, polystyrenes, including styrene-containing copolymers, such as e.g. B. acyl nitrile styrene, butadiene styrene and styrene vinyl benzyl halide copolymers, polycarbonates, cellulose polymers, polypropylene, polyvinyl chloride, polyethylene terephthalate and the like, as described in U.S. Patent No. 4,230,463; the description is by reference as if it were fully listed here. Preferred ceramic fibers are made of aluminum oxide from EI duPont de Nemour Co. and are described in U.S. Patent No. 4,069,157.

Header:

A one-piece head element is slidable in one direction relative to the other, namely either lengthways (x-axis) or in the transverse direction (y-axis), but before immersion the strand for surgical purposes. Be using a strand the head elements are vertically spaced apart and parallel to each other in a container arranged, e.g. B. by mounting a head element over the another against a vertical wall of the container, which acts as a spacer serves. This also applies to spacing one head element over the other with another Spacers, such as. B. rods, rods, struts, I-beams, channels and the like, for assembling several strands to a "group or a tuft of strands "(for brevity referred to as a "group"). To assembly into a group is one between the cast ones Ends of each individual fiber lying segment either along the x- or y-axis slidable because the fibers are loose in the strand being held.

The most preferred variant is each in one piece trained head element cast directly into a suitable material, from which the hardened cast resin head element is not removed, with no seal (thus referred to as "sealless") between the hardened Resin of the head element and the inner periphery of the permeate collector is required. If that in one piece trained head element is adhesively attached in a tub or "end cap", again, to form a permeate collection zone is not a seal required, although one can be used if the one-piece head member to be expanded.

The fixing material for fixing the Fibers in a finished head element (or on a fixing laminating agent) is either a thermosetting in the most preferred variant or thermoplastic artificial Resin material, optionally with glass fibers, boron or graphite fibers or similar reinforced is. Thermoplastic materials can be crystalline, such as. B.

Polyolefins, polyamides (nylon), polycarbonates and the like, be semi-crystalline, such as. B. polyether ether ketone (PEEK), or substantially amorphous, such as. B. polyvinyl chloride (PVC), polyurethane and the like. Thermosetting resins typically include polyesters, polyacetals, polyethers, cast acrylates, thermosetting polyurethanes and epoxy resins. In the most preferred variant, a "fixing" material (so called because it fixes the installation sites of the fibers relative to one another) is a material that is substantially rigid after curing over a thickness of approximately 2 cm and due to its hardness is generically referred to as "plastic". Such a plastic has a hardness in the range from approximately Shore D 30 to Rockwell R 110 and is selected from the group consisting of epoxy resins, phenols, acrylic resin derivatives, polycarbonate, nylon, polystyrene, polypropylene and polyethylene with an ultra-high molecular weight (UHMW PE). Polyurethane, which is available from Uniroyal Chemical Company under the brand name Adiprene ^® and Air Products under the brand name Airthane®, and epoxy resins, which are available as Epon 828 commercially are excellent fixing.

The resulting membrane device has: (i) a vertical strand of a plurality of fibers which can be moved back and forth to a limited extent and which together have a surface area in the range from 1 m ² to 1000 m ² , preferably from 10 m ² to 100 m ² , and which are mounted only in spaced-apart head elements; and (ii) a gas scrubber that creates a column of bubbles that rise within and near the base of the strand and envelop the strand. The bubbles produced have an average diameter in the range of about 0.1 mm to about 25 mm or more. A liquid component is selectively removed from the substrate.

Gas washing arrangement:

A gas washing arrangement has: (a) at least one strand or a group of gas-washed fiber strands which separate a desired permeate from a larger body of a multicomponent substrate with particles finely distributed therein with a size in the range from 0.1 μm to 44 μm, (b ) each strand having at least 20 fibers with upper and lower spaced cast-in connection areas in the upper and lower head element, the fibers being able to be moved back and forth to a limited extent in a bubble zone, and (c) an adapted gas distribution device for effecting a distribution of vertically ascending Bubbles in a column above and very near the top of the lower header, the length of the fibers being from at least 0.1% to less than 5% greater than the distance between opposite sides of the header. The adapted gas distribution device has passages through which gas flows continuously or intermittently, with a flow rate that is proportional to the number of fibers. The flow rate is essentially in the range of 0.47 - 14 cm ³ / sec, per fiber (0.001 - 0.03 scfm / fiber) (standard ft ³ per minute per fiber), typically in the range of 1.4 - 4.2 cm ³ / Sec / fiber (0.003 - 0.009 scfm / fiber). With a mini-strand, the area of the fibers is not used to define the amount of air used because the air flows substantially vertically along the length of each fiber.

The gas washing arrangement is as follows used: (i) together with a vertically adjustable spacer for mounting the head elements at a vertical distance from each other and in open fluid communication with (ii) a catcher to collect permeate; and (iii) sufficient air to generate of enough bubbles flowing through the strand between and in parallel flow up to the fibers, around the fiber surfaces essentially free of deposits from living microorganisms as well to keep small non-living particles in the substrate can be present.

With surprisingly little cleaning gas, that of one located between the fibers near their base parts Blown tube is released, the balance is Current over maintained for a long period of time, typically 50 hours to 1500 hours. The injection pipe of a gas distribution device is adjacent to that Top of the lower head element arranged to ascending a column Generate bubbles, with the fibers in the column flooded with bubbles are. A group of strands can also be "gas washed", with a or several air pipes between the lower head elements adjacent strands are arranged, in the most preferred variant also adjacent to the extreme Fibers of the first and last strands, so that at "n" head elements "n + 1" additional Air pipes are provided. The type of gas (air) manifold is not critical, provided that they prefer bubbles in a size range of about Delivers 0.1 mm to 25 mm, measured within a distance of 1 cm to 50 cm from the passages creating the bubbles.

Operation of the system:

The operation of the system is from the Positioning at least one strand, preferably a group, near a source for sufficient air or gas supply to maintain a desired Stroms and to enable the collection of permeate depending on at least one head element. On desired Current is reached and generates the appropriate transmembrane differential pressure the fiber under operating conditions.

The transmembrane differential pressure is preferably with a conventional Non-vacuum pump generated when the transmembrane differential pressure is sufficiently low and in the range of 0.7 kPa (0.1 psi) to 101 kPa (1 bar) is provided that the pump has the required Suction created. A pump that produces minimal suction can be used when there is sufficient "liquid head" between the substrate surface and the permeate extraction point is generated. As detailed below explained is also when a permeate stream has been generated by a pump the pump is not absolutely necessary because of the permeate of a "siphon effect" continues to flow. It is obvious that when operating with fibers that have a transmembrane differential pressure up to 101 kPa (14.7 psi), a non-vacuum pump performs adequately in a container that is not under pressure; and in the range of 101 kPa to about 345 kPa (50 psi) from a large liquid head or a pressurized container generated over the atmospheric pressure horizontal pressure used.

A method of separating Permeate from a substrate while maintaining relatively cleaner fiber surfaces in an array involves immersing a strand from restricted and essentially movable vertical fibers into the substrate, so that the top and bottom end caps of the strand are attached one above the other, with a plurality of fibers attached between headers is and the opposite Connection areas of the fibers in an open fluid connection with at least a head element is cast in; the working of the fibers a transmembrane differential pressure in the range of approximately 0.7 kPa (0.1 psi) to approximately 345 kPa (50 psi), the length the fiber is at least 0.1% to about 2% larger than the direct distance between opposite one another Top and bottom sides of a hardened resin in the head elements, so that the fibers in the inserted state are essentially vertical Form fiber strand; maintaining a substantially constant current, the one essentially equal to that initially achieved Current corresponds to indicating that the fiber surfaces are essentially free of Another buildup of deposits is when the is in equilibrium current is reached; collecting the permeate; and the removal of the permeate.

The method described above can be used when operating an anaerobic or aerobic bioreactor, with the membrane device according to the invention retrofitted has been. The anaerobic reactor is a closed vessel, and that Wash gas is a molecular oxygen-free gas, such as. B. nitrogen.

An aerobic bioreactor can have at least one gas-washed group of vertical cylinders Ranks are upgraded, each strand being made from 500 to 5000 fibers with a length of 1 m to 3 m, further with a permeate collector for operating the reactor without the numerous restrictions and limitations imposed by a secondary treatment system.

Typically it gives up in one one side closed tank no cross flow of the substrate over the Fiber surface. If there is a stream of substrate in a tank closed on one side through the strand is present, the flow is on the air supply below the strand or mechanical .mixing that is applied is used to keep the solids in suspension. As a general rule there is a larger current and a higher one Fluid velocity through the strand in a tank, into the one Substrate flows continuously, the fluid velocity over However, the fibers are generally too insignificant for growing microorganisms to prevent deposits, or suspended matter, e.g. B. microscopic small pebble particles to prevent them from settling on the fiber surfaces.

1 shows the results of a comparison of three runs, with one of the findings of Yamamoto from the 89 publication (curve 2 ) have been used, however, a venting device has been used which introduced air from the side and directed it radially inwards, as shown by Chiemchaisri et al. With a second pass (curve 1 ) the gas-washed arrangement described in the '424 patent is used, and the third pass (curve 3 ) the gas-washed strand described here is used, with the exception that the header elements were rectangular parallelepipeds (cuboids). The one with an arrangement of an inverted parabolic array with an air distribution device (Yamamoto et al), which in Wat. Sci. Tech. Vol. 21, Brighton, pages 43-54, 1989, and a parabolic array by Cote et al described in the '424 patent is compared to the current obtained by the vertical strand of the invention.

The comparison relates to the three arrangements with fibers with a nominal pore size of 0.2 μm with essentially identical bores and surface areas in 80 l tanks which are filled with the same activated sludge substrate. The differences between the Yamamoto et al experiment and the experiment described in the '424 patent are listed in the' 424 patent, and the conditions of the comparison are included by reference as if they were fully set forth here. The vertical strand used here differs from the strand described in the '424 patent only in the vertical configuration of the 280 fibers. each was approximately 1% longer than the distance between the spaced headers during operation. The air flow rate for the vertical line is 1.4 m ³ / hour / m ² when using a coarse bubble diffuser.

In 1 , in which the flow, ie liters per meter ² per hour per pressure unit (conventionally written as (Lmh / kPa)) as a function of the operating time of the three arrangements, is shown by the curve which is marked with the reference symbol 3 for the current in the vertical strand is approximately the same as the current generated by the parabolic strand, which is identified by the reference symbol 1 is designated. Each stream is shown to reach equilibrium in less than 50 hours, but after about 250 hours, it is seen that the current generated by the inverted parabolic array is decreasing, but the other two arrangements are reaching equilibrium.

2 Figure 12 shows an exploded view of a portion of a membrane device, referred to as "vertical strand" 10, and a lower header 11 one pair of head members, the other upper head member (not shown) being substantially identical; a drip pan 20 catches permeate through a line 30 is removed. The head element shown is a rectangular prism, but it can also be cylindrical if desired. Although the fibers 12 are tightly packed, they are not in contact with each other, but are spaced apart from each other by the cured resin arranged between them.

As shown, the open ends of the connection areas are located 12 ' of fibers in the same plane as the bottom of the head element 11 because the fibers are cast in in a conventional manner and the head member is split to expose the open ends. A specific casting process, in which the trough of a U-shaped fiber bundle is cast in, leads to the formation of two head elements. This method is described in the '424 patent (col. 17, lines 44-61); however, even cutting the cast fibers with a thin, high-speed diamond knife often results in damage to the fibers and causing the peripheral wall to collapse. Another conventional method for pouring fibers, described in U.S. Patent No. 5,202,023, has its ends dipped in resin or paint to prevent resin from entering the holes in the fibers during the pouring process. The ends of the bundles are then placed in molds and uncured resin is added to saturate the ends of the fiber bundle and fill the gaps between the individual fibers in the bundle and the flexible tubing in which the bundle is held. The hardened shaped ends are removed from the molds and the shaped ends are cut off (see bridging gaps 11 and 12 ). In any prior art process, disassembling the mold will damage the embedded fibers.

Therefore, a novel method for manufacturing a head element 11 in the shape of a rectangle applied to prisms. The method requires the manufacture of a composite head element with two liquids. A first liquid volatile material forms a "volatile laminating agent" of the composite head element in the solidified (hardened) state; a second liquid made of a non-volatile fixing material forms a "fixing laminating agent".

The first liquid is around connection areas poured from fibers, cools and freezes into a fleeting one laminating; the fibers in the volatile laminating agent then poured in again, this time by pouring the second liquid over that fixed volatile Laminating.

More specifically, the process includes To produce a finished head element for strand fibers, the following steps:

• Making a bundle of fibers in at least one array by a holding device with a Thickness according to a desired Lateral spacing between adjacent fibers is maintained;
• Holding the bundle in a first liquid, the connection areas of the fibers remain immersed until the liquid has solidified into a first adapted laminating agent, provided that the first liquid does not react with the fiber material;
• to water a second liquid over it first adapted lamination means for embedding the fibers in a desired one Depth and solidification of the second liquid to form a fixative Laminating agent on the first customized laminating agent, wherein the second liquid also essentially not either with the material of the fiber or that of the first customized lamination reacts;
• whereby a composite head element is formed in the connection areas of the fibers are cast in, preferably in a geometrical manner regular pattern, wherein the composite head member is a laminate of a volatile Laminating agent from a volatile Material and an adjacent finished head element in the form of a fixing laminating agent; and then
• Remove the first customized lamination without removing it a portion of the fixing lamination around the ends of the Keep fiber open and from the back of the head element protrude, with the open ends of a circular cross section exhibit.

The step-by-step procedure for producing an array with the novel head element is illustrated by an in 3 shown arrays as follows:

The fibers 12 are each cut to the same length with a sharp knife so that opposite ends of each fiber have a substantially circular cross-section. The fibers are coplanar side by side in a linear array on a planar holding device, such as. B. strips or cards 15 and 16 , arranged. The strips are preferably covered with an adhesive, e.g. B. a commercial polyethylene hot melt adhesive coated so that the fibers are glued to the strips and and opposite connection areas 12 " the fibers extend beyond the strips. between areas 12 ' the fibers are thus attached to the strips. Alternatively, the strips can be provided with parallel, spaced-apart grooves, which receive the fibers in a snug fit. The strips can be flexible or rigid. When the strips are flexible, they are glued together with the glued fibers one after the other in order to form an increasingly rigid stack for a head element with a desired geometry of the cast-in fibers. To prevent the strips from sticking, a regular pattern of linear rows can be created by attaching multiple arrays using rubber bands 18 or other clamps on rigid strips in a stack. The connection areas 12 " are thus kept spaced apart, the center distance of adjacent fibers preferably being in the range of 1.2- (1.2d) to about 5 times (5d) the AD 'd' of a fiber, more preferably in the range of 1.5d to 2d. Preferably the thickness of a strip is approximately the same as or relatively less than the AD of a fiber, preferably it is in the range of approximately 0.5d to 1d, which then becomes the distance between adjacent outer surfaces of the fibers in successive linear arrays.

After forming a first array become second and third arrays (which are not shown because they are are essentially identical to the first array) analogous to that first array produced and placed on this. There will be additional ones Arrays applied until the desired one Number of arrays combined in a bundle is, and the bundle is held vertically to close the bottom of the bundle to be poured in first form.

4 shows schematically a rectangular tundish 17 whose length and width dimensions essentially correspond to the longitudinal (x-axis) or transverse (y-axis) dimensions of the desired head element. The lower area of the bundle is immersed in a first liquid, which is at a level denoted by L1 in the tub 17 increases. In the most preferred variant, a liquid wax, preferably a water-soluble wax with a melting point below 75 ° C, such as. B. a polyethylene glycol (PEG) wax is used.

The depth to which the first liquid is poured depends on whether the strips 15 should be removed from the finished head element or should remain in it.

• A. First, pouring strand fibers into the top and bottom headers that make up the Strips are shown. (1) A first customized laminating agent is made with a thickness L1 (corresponding to the depth to which the first liquid was poured) of approximately 5-10 cm (volatile) so that 12 'and 12 "are spaced from each other and that (2) The second liquid, a curable water-insoluble liquid casting resin or a reaction component of the resin is poured over the surface of the volatile laminating agent so that it surrounds the fibers until the second liquid reaches a level L2 It solidifies around the fixing laminate (which forms the finished head member) with a thickness measured from level L1 to level L2 (the thickness is measured as "L1-L2" and is typically between about 1 cm and about 5 cm) form, which maintains the relative positions of the vertical fibers. Thus, a first composite header with the combined thickness of volatile and fixed Forming laminating agent. (3) Analogous to the description immediately above, the upper area of the bundle is cast into a second composite head element. (4) The composite headers are removed from their tundish and blown with hot air to melt the volatile laminating agent, leaving only the finished headers, each of L1-L2 thickness. The volatile material is then reused. Alternatively, a water soluble volatile material can be placed in hot water to dissolve the material and then the material is recovered from the water solution. (5) The ends of the fibers protruding from the rear permeate discharge side of the head members are open and maintain a circular cross section.
• B. Second, pouring is shown without removing the strips. (1) The first liquid is poured to a level L1 'below the cards, to a depth in the range of approximately 1-2 cm and solidified to form a volatile laminating agent L1'. (2) The second liquid is then poured to depth L2 over the volatile laminating agent and solidified to form a composite head member with a fixing laminating agent having a thickness of L1'-L2 '. (3) The composite header is removed from the mold and the volatile laminating agent is removed, leaving the connection areas 12 " protrude from the rear of the finished header, the rear being formed where the level L1 'was. The strips are in the finished head elements with a thickness of L1'-L2 ' 15 embedded (together with the rubber bands 18 , if used).
• C. The third is the pouring to make an upholstery laminate with embedded fibers on the opposite (front) sides of the headers from which the strips are removed. The intermittent snapping motion of the fibers often results in the fibers breaking around their circumference at the front-substrate interface. To address the hardness of the "fixative laminate", a "cushion laminate" is made from a softer material than that of the fixative laminate, integrally with the fixative laminate, by pouring a cushion fluid (so called because of its function in the cured Condition) over the fixing lamination to a depth L3, as in 4 shown. The depth gives elasticity around the circumference to minimize the risk of shearing. Such a cushioning liquid is rubber-like in the hardened state, has a hardness in the range of approximately Shore A 30 to Shore D 45 and is preferably made of a polyurethane or silicone or another material that adheres to the fixing laminating agent. After removal of the volatile laminating agent, the finished head member thus produced has the combined thickness of the fixing laminating agent and the cushioning laminating agent, ie L1-L3, when the strips 15 are cut away.
• D. The fourth is the manufacture of a seal laminate. The finished head element is preferably placed in a permeate trough with a seal arranged on the periphery 20 used as in 2 shown. Since it is easier to seal the tub against a seal laminate than against a seal provided near the periphery, a seal material with a hardness in the range from Shore A 40 to Shore D 45 forms a desired seal laminate that is integral with the rear side of the finished head element is formed. In the embodiment in which the strips are cut away, the volatile laminating agent is prepared as described above and a sealing liquid (so-called because it forms a seal in the hardened state) is poured to a depth L4 over the surface of the volatile laminating agent. The sealing liquid is then cured. By removing the volatile laminating agent and cutting away the strips 15 the finished head element remains with a combined thickness of the sealing laminating agent (L1-L4), the fixing laminating agent (L4-L2) and the cushioning laminating agent (L2-L3), ie a total thickness of L1-L3.

In another embodiment, the manifolds are integrally formed with a header to prevent the tub from being attached to the header with a sealing device and to locate one or more gas distribution lines at an optimal location near the base of the tow fibers after forming the tow. 5 shows a perspective view of a "one-piece trained single strand "100 with a finished head element 101 and a permeate tub 102 with a permeate extraction nipple 106 , which are formed in one piece, and vertical air pipes 103 that are to be embedded in the finished head element. The air tubes are preferably on both sides of the strand fibers with the supply air tubes 104 and 105 connected, which are inserted through bushings in the walls of the tub. The permeate nipple 106 is then inserted and an array stack is held vertically in the tub, in which a volatile laminating agent is formed, in which both ends of the fibers and the lower area of the vertical air tube 103 are embedded. Then a fixing lamination is formed over the volatile lamination in which the fibers are embedded to form a fixing lamination through which the open ends of the air tubes pass 103 protrude. The volatile laminating agent is then melted and through the nipple 106 deducted. In operation, permeate collects in the permeate trough and passes through the nipple 106 deducted.

6 shows a cross section of an integral single strand 110 with another integrally molded finished head element 101 with a thickness of L1-L2, but without an upholstery laminating agent, which is produced in a similar manner as described above. A permeate pan 120 with sides flared outwards 120 ' and transversely spaced through openings formed therein between side walls 111 and 112 prefabricated so that the tub is spaced above the lower part of the container.

Two air manifolds 107 , as in 7A or 7B are shown adjacent to the permeate pan 120 positioned and held in mirror image to each other, with the vertical air pipes 103 protrude through the openings in the sides 120 'and the ends 104 and 105 protrude from passages in the vertical walls on both sides of the permeate pan. The permeate extraction nipple 106 ( 6 ) is temporarily inserted. The stack of strips 15 is between the air pipes 103 vertically in the tub 120 positioned, which is filled to level L1 to form a volatile laminating agent, the level just below the lower edges of the strips 15 that cannot be removed. After solidification are the connection areas of the fibers 12 embedded in the volatile laminating agent, and the volatile laminating agent also fills the permeate tubes 106 , Then the second liquid is poured over the top surface of the volatile laminating agent until the liquid strips 15 covered, but the upper ends of the air pipes 103 leaves open. The second liquid then hardens to form the laminate of the composite header, which is then heated to allow the volatile material to be extracted after the permeate nozzle is withdrawn 106 is removed by this.

7A shows a perspective view with a schematic representation of an air manifold 107 with vertical air pipes 103 which run upwards from a transverse head element tube, from which the air ducts lead 104 and 105 protrude lengthways. The bore of the air tubes, which can be either "fine bubble diffusers" or "coarse bubble diffusers" or "aeration devices", is selected so that bubbles with the desired diameter are produced under operating conditions, the bore typically being in the range from 0.1 mm to 5 mm lies. Smaller diameter bubbles are preferably made with a perforated transverse tube 103 ' an air collection tube 107 ' , the feed air pipes 104 ' and 105 ' has produced, how 7B shown. In any case, the bubbles serve as a mechanical brush.

The strand fibers for the upper Header elements of the strand are analogous to the manner described above in a similar Poured permeate pan to form a finished head element with the exception that no air collection tubes are used.

8th shows a perspective view in cross section with a schematic representation of an embodiment in which a group of two strands in a single, integrally formed finished head element enclosure, generally with the reference numeral 120b is marked, is poured. The term "manifold enclosure" is used because the side walls 121 and 122 and the end walls (not shown) comprise a template into which air is introduced. Instead of in a permeate pan, permeate is collected by a permeate collecting line, which is provided for both fibers. In another upper enclosure (not shown) 120u , which is designed similarly, with the exception that it is designed as a channel-shaped flat-bottom trough (as a reversal for use as an upper head element) without molded-in air pipes, the mutually opposite connection regions of all the strand fibers are cast into the trough. Both the lower and the upper enclosure are used for operation 120b and 120u lowered with their strand fibers into a container of the substrate to be filtered. The sidewalls 121 and 122 do not need to rest on the lower part of the container, they can also be mounted on a side wall of the container.

The sidewalls 121 and 122 and the end walls are part of an integral arrangement with a platform connecting the walls 123 , and they are aligned risers 124 molded into the platform. The risers are similar to an inverted test tube, the diameter of which only needs to be so large that an air tube 127 through the top part 125 of the inverted test tube can be used. As shown, preferably "n + 1" rows of air tubes are for "n" stacks of castings Arrays provided. The crenellated platform 123 has risers 124 on between which channels 128 and 129 lie. The canals 128 and 129 are each wide enough to hold a stack of fiber arrays 12 record, and the riser pipes are wide enough that the air pipes are long enough 127 can be inserted into these so that the upper open ends 133 of the air pipes from the upper surfaces of the fixing material 101 protrude. The lower ends 134 of the air tubes are cut at an angle to minimize insertion and positioned over the surface S of the substrate. The channel 129 is designed such that it is a permeate extraction tube 126 forms one piece with the platform 123 is trained. The side wall 122 is with an air nipple 130 provided by the air into the from the walls of the enclosure 120b and the area S of the substrate under the platform 123 formed template is entered. Each stack is as above using 6 described, in the most preferred variant, by forming a composite header made from volatile PEG wax and epoxy resin around the stack of arrays that are between the rows of risers 124 are positioned, ensuring that the open ends of the air tubes are above the epoxy fixing material, and melting the wax through the permeate extraction tube 126 , When air is introduced into the enclosure, the air is distributed through the air tubes that are located between the strands and around the strands.

9 shows a schematic representation of a strand with upper and lower head elements 41u respectively. 41b and in each show the protruding upper and lower ends 12u " and 12b " that the side of the head member has not been cut to expose the fibers. The height of the adjacent intermediate areas 12u ' respectively. 12b ' corresponds to the depth of the hardened fixing material.

It is apparent that the essential feature of the molding process described above is that a volatile laminating agent is formed, in which the openings of the connection regions of the fibers are embedded before the intermediate regions adjoining them 12u ' and 12u " and 12b ' and 12b " are each fixed in a fixing lamination of the head element. An alternative choice of material is to use a volatile cast composite that is soluble in a non-aqueous liquid in which the fixing material is not soluble. Another choice is to use a water-insoluble volatile material that is also insoluble in non-aqueous solutions that are typically used as solvents, but the volatile material has a lower melting point than the final casting material, which can be water-soluble or non-water-soluble.

The volatile material is inert both relative to the fiber material as well as the final casting material, and the fleeting Material and the fixing material are insoluble in the other material. Preferably forms the fleeting Material a solid with a substantially smooth surface critical factor, however, is that the volatile material at least partially cured must be, to a sufficient extent, that the shape of the head element is maintained and that the material is a solid above that Temperature remains at which the fixing material is in the head element shape is entered. The fleeting Laminating agent is essentially inert and in the final casting material insoluble, so the fleeting Removable laminating agent adheres to the fixing laminate.

The head element taken out of shape is either warmed or the solvent is extracted, for the fleeting To remove laminating agents. Typically the fixing material at a first curing temperature hardened to a solid mass, being the temperature not higher is preferred as the melting point or Tg of the volatile laminating agent at a temperature below about 60 ° C; the Solid is then post-cured at a temperature high enough to the fleeting Melt material, but not so high that the hardening of the Fixing material or the fiber properties are impaired. The fleeting Material is removed as described below using the removal procedure from the fleeting Material and the curing temperature the final casting material depends.

According to 2 has the head element 11 Front and back walls on that of vertical (z-axis) edges 11 ' and longitudinal (x-axis) edges 13 ' are educated; Sidewalls by edges 11 ' and transverse edges 13 " (y-axis) are formed; and a base part 13 that of edges 13 ' and 13 " is formed.

The drip pan 20 is dimensioned so that it is the base part 13 over a permeate collection zone in the tub in the fit. This is done by making a rectangular trough with a base part 23 with substantially the same length and width dimensions as that of the base part 13 , The periphery of the tub 20 has a step formed on the periphery, as in 2A shown in the wall 20 ' the tub in a step section 22 with an essentially horizontal shoulder 22 " and a substantially vertical support wall 22 ' ends.

2 B shows a bottom view of the underside of a head element 13 showing the open ends of the fibers 12 ' , using cast resin to prevent them from touching. The geometrical distribution of the fibers forms a regular peripheral boundary 14 (shown in dots) that defines the peripheries of the open ends of the outermost fibers.

Permeate flows from the open ends of the fibers into the base 23 the tub 20 and leaves the collecting zone through a permeate extraction line 30 which in the lower part of the tub in open fluidver bond with the interior of the tub is arranged. When the strand is backwashed, backwash fluid flows through the fibers and into the substrate. If desired, the sampling line can be positioned on the side of the tub as by line 30 ' shown. Regardless of whether the operation is only under the influence of gravity or by means of a pump for generating an additional suction effect, it is obvious that a fluid-tight seal between the periphery of the head element 11 and the stage located on the periphery 22 the tub 20 is required. Such sealing is done by conventional means such. B. a suitable seal or sealant, typically a polyurethane or silicone resin, between the lower periphery of the head member 11 and the level 22 , According to 2 permeate flows down, but it could also be from the upper permeate port 45u in the upper permeate pan 43u be removed (see 9 ).

In 9 and 2A are six rows of fibers 12 on both sides of a gas distribution line 52 shown, which crosses the length of the rows along the base part of the fibers. The molded connection end areas 12b " open into the permeate pan 43b , Because the areas 12u ' and 12b ' of the individual fibers 12 are cast in and the fibers 12 are preferably 1% to 2% longer than the fixed distance between the upper and lower head elements 41u and 41b , the fibers between mutually opposite head elements run essentially parallel to one another, but are, in particular, arranged parallel to one another near the head element. Also the connection end areas 12u " and 12b " the fibers protruding from the head members with exposed open ends are held parallel to each other. The fibers are below the bottom of the lower head element 41b and above the top of the top header 41u in front. The choice of fiber spacing in the head element determines the packing density of the fibers near the head elements, but the fiber spacing is not essential since the spacing does not significantly affect current during operation.

Since the length of the fiber normally changes during operation, the extent of the change depending on the particular fiber composition, and the distance between the upper and lower head elements is critical, it is desirable to mount the head elements such that one in the vertical direction relative to the other is adjustable, as indicated by arrow V. This is done by attaching the tub 43u on a plate 19 with vertically spaced passages 34 through which a threaded bolt 35 used and with a mother 36 is secured. The threaded bolt 35 is in a fixed mounting block 37 ,

The fiber density in a head element is preferably selected such that the maximum membrane surface area per unit volume of the substrate is achieved without impairing the circulation of the substrate through the strand. A gas distribution facility 52 , such as B. a perforated air tube, delivers air into the strand so that gas (air) bubbles rise up, getting stuck on the outer surfaces of the fibers and thus washing them efficiently. If desired, additional air pipes can be used 52 ' on both sides of the strand near the lower header 41b be placed as shown in phantom to create additional air washing performance. Whether permeate through the port 45u from the top header or through the port 45b Removed from the lower header or from both depends on the particular application, but in all cases the fibers are essentially vertical in orientation.

The vertical strand becomes one Substrate used to assume a substantially vertical profile, however, it has no structural shape. The shape it has changed itself continuously, the degree of change depending on the flexibility of the fibers, their length, the overall dimensions of the strand and the degree of movement the fibers from the substrate and the oxygen-containing gas from the gas distribution device is awarded.

10 shows a typical arrangement, referred to as a "wall-mounted group", which has at least two strands arranged side by side, generally with the reference numerals 40 and 40 ' with fibers 42 and 42 ' are designated; the fibers 42 are in the top and bottom headers 41u respectively. 41b cast; and the fibers 42 ' are in header elements 41u ' and 41b ' cast; the head elements 41u and 41b are with permeate collection devices 46u respectively. 46b equipped; the head elements 41u ' and 41b ' are with permeate collection devices 46u ' respectively. 46b ' equipped; and the strands share a gas distribution device 50 , A "group" of strands is typically used to retrofit a large deep tank from which permeate is to be removed using a vacuum pump. In a large container, multiple groups of strands can be used side by side in a tank. Each strand has several rows (only one of which is shown) of fibers 42 and 42 ' in upper head elements 41u and 41u ' and lower head elements 41b respectively. 41b ' on, and arms 51 and 51 ' the gas distribution device 50 are between the lower head elements 41b and 41b ' arranged near their base parts. The top head elements 41u and 41u ' are on one of their ends with fastening clips 53 and 53 ' and suitable fasteners such. B. screws 54 , attached to a vertical inner surface of the wall W of a tank. The wall W thus serves as a spacing device which fixes the distance between the upper and lower head elements. Each upper head element is equipped with a permeate drip pan 43u respectively. 43u ' provided with permeate extraction lines 45u and 45u ' and with a permeate manifold 46u is connected, through which permeate, which is filtered into the drip pans, is continuously removed. Each head element is sealed around its periphery to the periphery of every other drip pan.

The strand fibers shown in this perspective view (of which only one array is shown for clarity) are in the form of an elongated rectangular parallelepiped, the sides of which are irregularly shaped due to the arbitrary displacement of the fibers from one side to the other as they move back and forth when immersed in a substrate. An elongated rectangular parallelepiped shape is preferred because it enables fibers to be packed tightly and yet allows the fiber surfaces to be washed with bubbles. In this form, a strand can have 10 to 50 fiber arrays across the width 'w' in the longitudinal direction of the head elements 41u . 41b and 41u ' . 41b ' are formed, each array having fibers that run along the length 'l' in the transverse direction of each head member. Air tubes on both sides of a strand effectively clean the fibers when there are fewer than 30 arrays between the air tubes. A string of more than 30 arrays is preferably also supplied with air from the center, such as through the air tube 52 in 9 shown.

Thus, when approximately 100 fibers are arranged closely together along the length 'l' in the transverse direction of an array and 25 arrays are provided in one strand in a header with a width 'w' in the transverse direction, the opposite terminal end regions of 2500 fibers in that head elements 41u and 41b cast. The open ends of all fibers in the headers 41b and 41b ' point down into the collecting zones in the collecting trays 43b respectively. 43b ' , and those of all fibers in the head elements 41u and 41u ' point down into the collecting zones in the collecting trays 43u respectively. 43u ' , The sampling lines 45u and 45u ' are with the permeate manifold 46u connected through itself in the upper sumps 43u and 43u ' accumulating permeate is typically extracted continuously. If the permeate flow is large enough, it can also be via the extraction lines 45b and 45b ' that with the permeate manifold 46b are connected by the sumps 43b and 43b ' be removed. If permeate is withdrawn at the same level as the permeate extraction lines 45u . 45u ' and the manifold 46u are arranged, and the transmembrane differential pressure of the fibers is in the range of 35-75 kPa (5-10 psi), the manifold can 46u be connected to the suction side of the centrifugal pump, which generates an appropriate required inlet height (NPSH).

Generally, the permeate is withdrawn from both the top and bottom headers until the current is reduced to a level so low that backwashing of the fibers is required. The strands can be made by introducing a backwash fluid through the upper permeate collection line 46u and removing the fluid through the lower manifold 46b be backwashed. Typically, 3 to 30 strands can be coupled together to establish an internal fluid connection through the manifolds, the permeate extraction device and the fibers and to establish an external fluid connection through an air manifold. Since the permeate removal device is also used for backwashing, it is generally referred to as a "liquid circulation device" and only as a permeate removal device if it is used to remove permeate.

When inserted into a substrate with floating and loosened organic and inorganic particles remain most organic Polymers float in a vertical position. The fibers in the strand float in the substrate with the fiber ends anchored in the headers are. This is because (i) the permeate is essentially pure water with a smaller specific weight than that of Is substrate and most of the polymers from which the fibers are made also have a specific gravity of less than 1, and (ii) the fibers of bubbles with which they are in contact, to be kept floating. Ceramic or glass fibers are heavier than water.

An air distribution manifold runs adjacent to the strands 50 below the base part of the fiber bundle, preferably below the horizontal plane through the horizontal center lines of the head elements. The manifold 50 is preferably in two perforated arms 51 and 51 ' divided that the basic parts of the head elements 41b respectively. 41b ' are arranged adjacent so that when air is discharged through holes in each area 51 and 51 ' Ascend bubble columns adjacent to the fiber ends and then flow along the fibers through the strands. If desired, additional areas (not shown) may be used which are adjacent to the base portions of the lower header but located on the outside of each lower header to create additional air columns along the outer surfaces of the fibers.

The type of gas (air) manifold is not critical, provided that it provides bubbles in a preferred size range of about 1 mm to 25 mm, measured 1 cm to 50 cm from the passages, in to which they are generated. If desired, any area 51 and 51 ' embedded in the top surface of each head member and the fibers can be molded around the area, thereby ensuring that the air passages in the areas 51 and 51 ' not to be clogged with casting compound. If desired, additional arms of the air tubes can be placed on either side of each lower header so that fibers from each header are supported by columns of both sides of the rising air.

The air can be continuous or are generated intermittently, with better results generally with a continuous air flow can be achieved. The amount of generated Air hangs on the type of substrate, the requirements regarding the type on microorganisms and the ability to insert the fiber surfaces.

11 shows a schematic representation of a further embodiment of an arrangement, which is referred to as a "free-standing group" of strands, two of which have the reference symbol 60 are provided. The group is said to be "free-standing" because the spacer between the headers is provided with the strands, usually because the fastening of the strands to the wall of a container is less effective than placing the group at a distance a wall. For the rest is the group 60 analogous to that in 10 shown, formed on the wall mounted group.

Every group 60 with fibers 62 (of which only a single row of the plurality of regularly spaced vertical arrays is shown for clarity) is between the upper and lower manifolds 61u and 61b used in a substrate 'S'. The lower head elements rest on the bottom of the container. The upper head elements are on rigid vertical air pipes 71 and 71 ' attached, through which air is introduced into a tubular air manifold, which is generally designated by the reference number 70 is designated. The manifold 70 has: (i) the vertical tubular arms 71 and 71 '; (ii) a lower transverse arm 72 that runs the length of the bottom header 61b ' is perforated and attached to it, the arm 72 with a longitudinal tubular arm 73 and optionally another longitudinal arm (not shown) 73 ' , the mirror image of the arm on the side removed from the head elements 73 is trained, communicates; and (iii) transverse arms 74 and 74 ' in open connection with 72 and 73 , with arms 74 and 74 ' along the visible transverse sides of the head elements 61b and 61b ' are perforated and 74 and 74 ' with the tubular arm 73 ' can be connected if the latter is provided. The vertical air pipes 71 and 71 ' also have the additional function of a spacer between the first upper head element and the first lower head element and since the remaining head elements in the group are connected to one another in a similar way (not shown) by rigid lines, the head elements become more vertical Direction and transverse direction kept apart. Since all arms of the air manifold are openly connected to the air supply, the even air distribution is simplified.

As described above, the headers are 61u and 61u ' each fluid-tight with collecting zones in collecting trays 63u respectively. 63u ' connected and has each tub extraction lines 65u and 65u ' on that with longitudinal liquid lines 81 and 81 ' are connected. Header elements are analogous to this 61b and 61b ' each fluid-tight with collecting zones in collecting trays 63b respectively. 63b ' connected and has each tub extraction lines 65b and 65b ' on, with (not shown) longitudinal lines 82 and 82 ' are connected. As shown, sampling lines are shown for both the top and bottom headers and both in front of and behind the headers. In many cases, permeate is only taken from an upper manifold that is provided only on one side of the upper header. A lower manifold is provided for backwashing. The backwashing fluid typically flows through the top manifold, through the fibers and into the bottom manifold. The additional manifolds at the rear ends of the upper and lower head elements not only result in a more uniform distribution of the backwashing fluid, but also provide a holder for the head elements connected to one another. It is obvious that in the absence of the rear upper connecting pipe 81 ' an upper head element, such as. B. 61u , by a different connection to the head element 61u ' or a spacer strut between the head elements 61u and 61b must be spaced from the lower head element.

In the optimal execution mode shown, each upper head element is provided with rigid PVC pipe nipples, which are connected by means of fittings such. B. L-gene and T-shaped elements, with the upper lines 81 respectively. 81 ' can be coupled. Similarly, each lower header is with lower leads (not shown) 82 and 82 ' connected, and / or spacing struts are provided to impart additional rigidity, depending on the number of head elements to be connected. Permeate is withdrawn through an upper line and all pipe connections, including the air connection, are above the liquid level in the container.

The fiber length (between the head elements) in a strand is essentially chosen so that efficient use an economic one Air volume is achieved to achieve an optimal flow over a long period of time. More to consider Factors include the depth of the tank in which the group should be used, the positioning of the liquid and air manifolds and the convection pattern in the tank.

14 - 17 show specific representations of preferred embodiments of the cylindrical vertical strand. 14 shows a side view in cross section with a schematic representation of a vertical cylindrical strand 210 , which rests on the bottom F of a tank, the strand of two having similar designs upper and lower cylindrical end caps 221 respectively. 222 has that serve as permeate sumps. drilling 226 and 227 in the upper and lower end caps are with permeate sampling tubes 231 respectively. 232 provided that are in fluid-tight connection with these. Permeate that is withdrawn through the pipes is in a permeate extraction manifold 230 merged. A finished upper / lower head element is directly molded into each end cap, the upper head element 223 essentially identical to the lower head element 224 is executed. Each head element is made by pouring fibers 212 in a resin, such as. B. a polyurethane or an epoxy resin, with sufficient rigidity to hold and seal the fibers under operating conditions. A commercially available end cap for a polyvinyl chloride "PVC" pipe is the most preferred variant; for strands with a large surface area, larger head elements are formed by commercially available glass fiber reinforced end caps for cylindrical tanks. It is important that the fibers do not touch each other, but are spaced apart by hardened resin. It is also important that the cured resin under operating conditions of the strand at the lower areas 212 ' each fiber adheres and seals it against fluid leakage. A visual inspection of a seal is carried out on the peripheries of the fibers, on the upper (front) and lower (rear) sides 223u respectively. 223b of the top header 223 and the front and back sides 224u respectively. 224b of the lower header 224 are sealed. A conventional finished head member can be used with the ends 212 ' of the fibers with the bottom 224b (essentially on the same level). The optimal ends are in the open ends 212 ' of the fibers from the lower (rear or bottom) side 224b before, although this cannot be seen through an opaque end cap.

The finished top header 223 (the fixing laminating agent) remains on the periphery of the end cap 221 stick if the volatile laminating agent through a hole 226 is removed in the upper head element; and the finished lower head element remains the same 224 on the periphery of the end cap 222 stick if the volatile laminating agent through a hole 227 Will get removed.

The strand fibers 212 are preferably formed in arrays that are in a geometric configuration, such as. B. a spiral roll are bundled. A head element is produced in a manner analogous to the way that is based on 4 by pouring the lower end of the spiral roller. 14A who have a bottom view of the back side 224b of the head element 224 shows an illustration of the spiral pattern of openings in the ends 212 ' of the fibers. An injection tube is preferred before the array is rolled up into a spiral 240 (in 15A shown) with a rigid air supply pipe 242 placed in the array so that the air supply tube is held axially in the middle of the roll when producing a spiral roll.

14B shows a bottom view of the rear side 224b with a further configuration in which a series of circular arrays with ever increasing diameter is formed, each being a small predetermined amount larger than the previous one and the arrays are preferably adhesively attached to the next one near their upper and lower peripheries, to form a dense mass of cylindrical fibers. In such a mass of fiber, referred to as a series of circular rings, each array is attached to both an adjacent array with a next smaller diameter and an adjacent array with a next larger diameter, with the exception of the innermost and outermost arrays, which are the smallest and have the largest diameter. The pattern in the header 224 shows the ends 212 ' the fibers after pouring the nested arrays.

14C shows a bottom view of a lower (rear) side 224b with multiple arrays in the header 224 are arranged like a string. The arrays are formed on pairs of strips, each of which has a length corresponding to its position as a string in a casting ring into which the strand fibers are to be cast. That is, each array is formed on strips of decreasing width, measured from the central array, which is formed on a strip of width slightly smaller than the inside diameter of the pouring ring into which the stack is to be poured , The arrays are stacked in the ring, with the widest array in position corresponding to the ring diameter. With a chosen fiber 212 applies that the larger the area required in a strand, the greater the number of fibers in each array, the larger the diameter of the ring and the wider each string-like array. The multiple arrays are preferably glued together by coating the fiber surfaces with an adhesive before placing a strip of the subsequent array on the fiber. Alternatively, the bundled arrays can be held with a rubber band before being inserted into the casting ring. The resulting string-like pattern in the head element 224 shows the ends 212 ' the fibers after pouring the nested arrays.

A detail of an injection pipe 240 is in 15A shown. The star-shaped injection pipe 240 with radially outwardly projecting tubular arms 241 and a centrally located feed attachment 242 provides air that is directed into the tubular arms and discharged into the substrate via air passages in the walls of the arms. One with the centrally positioned feed attachment 242 connected air supply pipe 244 delivers air to the blowing tube 240 , The lower end of the centrally located approach 242 is with short protruding nipples 245 provided, the inner ends are soldered to the approach. The outer ends of the nip pel have threads. The centrally located approach and the nipples can easily be inserted in the middle of the strand fiber mass. After centering the arms 241 , which have a thread at one end, screwed to the outer ends of the nipples.

According to 14 the lower end cap rests 222 on the bottom F of a tank near a vertical wall W, on which a vertical fastening strut 252 with suitable fasteners, such as. B. a mother 253 and a screw 254 , is attached. A U-shaped bracket 251 stands laterally from the base part of the fastening strut 252 in front. The arms of the U-shaped bracket hold the periphery of the upper end cap 221 , and to ensure that the end cap remains in place, it is attached to the U-shaped bracket with a right angle bracket (not shown) and fasteners. A slot in the strut 252 allows the U-shaped bracket to be raised or lowered so that the desired distance between opposite sides 223b and 224u the upper or lower head elements is a desired amount smaller than the length of a cast fiber, measured between these surfaces. The adjustability is particularly desirable when the fiber length normally changes during operation.

According to 14 if desired, permeate is only from the top tube 231 see a permeate connection pipe 233 (shown in phantom) by the head elements 223 and 224 into the bulk of strand fibers 212 used, creating the permeate collection zone 229 in the lower end cap in open fluid communication with the permeate collection zone 228 is connected in the upper end cap; and the hole 227 comes with a stopper 225 locked as in 15 shown. Because in such circumstances it is unimportant if the lower ends 212 ' the fibers are inserted and the permeate collection zone 229 the zone cannot perform any essential function 229 be filled with resin.

16 shows a strand 270 with top and bottom end caps, into the sealed top and bottom ring headers in top and bottom rings 220u respectively. 220b are molded in after the fibers in the strand have been checked for defects. A rigid air supply pipe 245 is positioned in the spiral roll as described above and the lower end of the roll is cast around a lower finished head member 274 to form in the bottom end 246 of the air supply pipe is poured in, the position of the arms 241 of the injection pipe just above the top 274U of the head element 274 is fixed.

In an analogous way, an upper head element 273 in the ring 220u trained and the top end 247 of the air supply pipe 245 through an axial bore 248 in the top end cap 271 used that over the ring 220u is pushed, the outer periphery of which is coated with a suitable adhesive, around the ring 220u in the end cap 271 seal. The periphery of the upper end 247 is in the end cap 271 sealed with any conventional sealant.

17 shows a schematic representation of a further embodiment of a strand 280 , where a rigid permeate tube 285 concentric in a rigid air supply pipe 286 which is held axially in the strand fibers 212 between opposite top and bottom headers 283 and 284 is poured into the top and bottom rings 220u and 220b are arranged, which in turn in end caps 281 respectively. 282 are sealed. The bottom end is for easier manufacture 285b of the permeate tube 285 with a snug fit in a socket 287 arranged and sealed there. The socket 287 and the end 285b are then in the lower end 286b of the air supply pipe 286 inserted and sealed there, so that the annular zone between the outer surface of the permeate tube 285 and the inner surface of the air supply pipe 286 Air conducts to the base of the fibers but does not allow permeate to enter the annular zone. The air supply tube is then placed on an array and the array is rolled up into a spiral which is held at each end with rubber bands. The lower end of the roll is in a ring 220b placed, and a lower ring header is finished with a finished header as described above 284 educated. Preferably, a relatively rigid elastomer with a hardness in the range from 50 Shore A to approximately 20 Shore D is used, and in the most preferred variant, a polyurethane with a hardness in the range from 50 Shore A to approximately 20 Shore D is used, measured as described in ASTM D-790, e.g. B. PTU-921 from Canadian Poly-Tech Systems. For making the top finished head element 283 the air supply pipe, as in 5 used, fitted through an O-ring provided in a central bore in a plate to prevent loss of casting resin from the ring and volatile resin and finishing resins which are poured into the ring and cured one by one. The lower finished head element 284 is with intermediate areas embedded in it 212b ' trained, the connection areas 212 ' protrude from the rear of the head element. The top finished head element 283 is with intermediate areas embedded in it 212u ' trained, the connection areas 212u " protrude from the front of the head element. When the finished headers 283 and 284 are made and the fibers have been checked for defects, the upper end 286u of the air supply pipe 296 through a central hole 288 in the top end cap 281 inserted and in the hole with a sealant or a collar 289 sealed. Preferably the permeate tube 285 , the air supply pipe 286 and the collar 289 Made of PVC so that they can be easily glued together to create leak-tight connections.

As shown, permeate can pass through the permeate tube 285 from the permeate collection zone in the lower end cap 282 and separately from the lower end cap 281 through a permeate extraction port 281p can be removed, which can be provided with a thread for attachment to a pipe fitting. Alternatively, the permeate port 281p be closed with a stopper and can permeate through the permeate tube 285 can be removed from both end caps.

The top end 285u of the permeate tube 285 and the top end 286u of the air supply pipe 286 through a T-fitting 201 inserted through the air to the air supply pipe 286 is fed. The bottom end 201b one of the arms of the T-shaped element 201 is pushed onto the air supply pipe and sealed around the air supply pipe. The top end 201u the other arm is in a reducing bush 202 used and sealed around the permeate tube. Air entering the inlet 203 of the T-shaped element 201 is supplied, the annular zone between the permeate tube and the air supply tube flows down and passes through opposite ports 204 in the lower area of the air supply pipe, just above the top 284u of the lower header 284 , out. The ports are preferred 204 threaded around the ends of the arms 241 to be screwed together so that an injection tube is formed, the air is essentially uniform over and above the surface 284u distributed. Additional ports can be provided along the length of the vertical air supply tube, if desired.

In a further embodiment of the invention, a bioreactor is retrofitted with several groups of strands, which are shown schematically in the side view in FIG 12 and the top view in 13 are shown. The clarification tank is a large circular tank 90 with a vertical circular outer baffle 91 , a vertical circular inner baffle 92 and a floor 93 that tends to discharge accumulated sludge toward the center (apex). Alternatively, the baffles may be individual, closely spaced rectangular plates arranged in outer and inner circles, but continuous cylindrical baffles (shown) are preferred. Regardless of which baffles are used, they are arranged in such a way that their lower peripheries are at a selected vertical distance above the floor. Feed material is through a feed line 94 in the bottom of the tank 90 entered until the substrate level above the outer baffle 91 lies.

A group 60 several strands 10 , analogous to those in the 10 shown group, each strand in 9 is shown, against the periphery of the inner wall of the bioreactor with suitable fasteners in an outer annular permeate removal zone 95 ' ( 13 ) between the circular outer baffle 91 and the wall of the tank 90 used at a depth sufficient to immerse the fibers. A clarification zone 91 ' is between the outer circular baffle 91 and the inner circular baffle 92 educated. The inner circular lead bleach 92 forms a vertical axial passage 92 ' , through the substrate into the tank 90 to be led. The strands form a dense curtain of fibers in the form of radial, essentially planar vertical arrays, as in 9 shown between top and bottom headers 41u and 41b are cast in. Permeate is through a manifold 46u withdrawn and air through an air manifold 80 entered, which runs along the inner wall of the tank and branches into air distribution arms between adjacent head elements, including outer distribution arms 84 ' on both sides of each lower header 41b at each end of the group. The air manifold 80 is between strands in the permeate extraction zone 95 ' positioned such that bubbles contact substantially the entire area of each fiber that is continuously flooded with bubbles. Because the fibers are substantially vertical, the air is in contact with the fiber surfaces longer than would be the case if they were arcuate, and the air is most efficiently used to maintain a strong current for a longer period of time than otherwise the case would be used.

It is apparent that when the tank is at ground level, the liquid head is insufficient to produce the desired liquid head under the force of gravity alone. Without an adequate siphon effect, a centrifugal pump can be used to generate the required suction. Such a pump should be able to run dry for a short period of time and a vacuum of 25.5 cm (10 ") - 51 cm (20") AC or -35 kPa (-5 psi) to -70 kPa (-10 psi) can maintain. Examples of such pumps with an output of 18.9 l / min. (5 gpm) @ 15 "WS are (i) centrifugal pumps with flexible impellers, e.g. Jabsco ^® # 30510-2003; (ii) air-driven diaphragm pumps, e.g. Wilden ^® M2; (iii) pumps with progressive cavity, e.g. Ramoy ^® 3561; and (iv) peristaltic pumps, e.g. Waukeshap SP25.

example 1

The microfiltration of an activated sludge at 30 ° C with a concentration of 25 g / l total suspended matter (2.5% TSS) is carried out with a strand of polysulfone fibers in a pilot plant tank. The fibers are "air washed" at a flow rate of 12 CFM (0.34 m ³ / min), with a built-in coarse bubble diffuser producing bubbles with a nominal diameter in the range of approximately 5 mm to 25 mm. The air is not only sufficient for adequate washing, but also for the oxidation requirements of the biomass out. The fibers have an OD of 1.7 mm, a wall thickness of approximately 0.5 mm and a surface porosity in the range from approximately 20% to 40% with pores with a diameter of approximately 0.2 μm. The strand, comprising 1440 fibers with a surface area of 12 m2, is attached to the wall of the tank, the vertical distance of the head elements being approximately 1% smaller than the length of a fiber in the strand, provided the fiber is in the relaxed state , The opposite ends of the fibers are cast into upper and lower head elements, each about 41 cm long and 10 cm wide. The fixation material of the headers is an epoxy resin with a hardness of approximately 70 Shore D with additional upper and lower laminators made of softer polyurethane (approximately 60 Shore A and 30 Shore D respectively) above and below the epoxy resin laminate, and the fibers are at a depth cast in sufficient that their open ends protrude from the bottom of the head member. The average transmembrane differential pressure is approximately 34.5 kPa (5 psi). Permeate is withdrawn by a pump that produces approximately 34.5 kPa (5 psi) suction through lines connected to the catch pan of each header. Permeate is withdrawn at a permeability of approximately 0.7 lm ² h / kPa, resulting in approximately 4.8 l / min of permeate with an average haze of <0.8 NTU, which is a haze that cannot be seen with the naked eye.

Example 2

Comparison of the operation of a vertical strand (ZW 72) with different orientations In the following comparison, three pairs of identical strands with equally relaxed fibers are positioned in different ways via ventilation devices in a bioreactor (as specified). Each pair is exposed to the same air supplied by identical ventilation devices. Rectangular but not square headers have been chosen to determine whether there is a difference between two flat horizontal orientations that would not exist in a horizontal strand with cylindrical headers. A pair of identical rectangular strands each with headers 41.66 cm (16.4 inches) long (x-axis), 10.16 cm (4 inches) wide (y-axis) and 7.62 cm (3 inches) high (z-axis), in which 1296 Zenon ^® MF200 microfiltration fibers with a nominal fiber area of 6.25 m2 are cast, was tested in three different orientations in a bioreactor for the treatment of household waste water. The fibers used are the same as in the example described above 1 , The distance between opposite sides of the headers is 90 cm (35.4 inches), which is approximately 2% less than the length of each fiber cast into these headers.

In a first test, the two (first and second) strands, each in the same direction along the longitudinal axis with a 2.5 cm (1 inch) spacer stacked laterally between the head elements, the head elements each strand has a horizontal flat orientation (an area of 41.66 cm x 7.62 cm) and at a distance of 7.62 cm (3 inch) about the floor on which the ventilation equipment in the form of three adjacent 3 mm linear tubes (0.125 ") large openings are arranged, are positioned. The first strand that goes directly over the aerators is arranged is therefore called "lower Strand ".

In a second test, the same first and second strands each by 90 ° the longitudinal, namely the x-axis, rotated and placed next to each other next to each other. This "horizontal 90 °" orientation (area of 10.16 cm x 7.62 cm) is thus spaced from the ventilation devices like the previous test.

In a third test, the first and second strands are placed side by side in vertical orientations, as in 9 shown, with the exception that there is no internal ventilation device.

With every test, the fibers supplied with an identical amount of air in every orientation. Permeate was pumped with a required inlet height (NPSH) from 0.3 bar (10 "Hg) taken. The conditions were kept constant until observed was that for each test current was essentially constant, and this was then the equilibrium value. After this occurred each strand was pulsed back with permeate every 5 minutes for 30 seconds, to keep the current at the equilibrium value.

The test conditions for each of the three runs described above were as follows: TSS in the bioreactor 8 g / l; Biomass temperature 19 ° C Air flow rate 0.2124 m ³ / min / strand; Suction height on the fibers 25.4 cm Hg

18 shows a bar chart showing the average current over a period of time of 24 hours for each orientation of the strand as follows: orientation Average current l / m ² / hour over 24 hours Horizontal flat 21.2 LMH Horizontal 90 ° 17.8 LMH Vertical 27.7 LMH

This finally demonstrates that with vertical orientation of the strand fibers, the largest total current is produced.

Example 3

Comparison of the positions of the ventilation device inside and outside of the strand fibers:

This test measures the difference in flow in a wastewater treatment bioreactor contaminated with ethylene glycol, the difference depending on how a single cylindrical vertical strand (ZW 172) with a nominal area of 16 m ² with 3.5 l / min. (7.5 scfm) is ventilated. The strand is as in 16 shown, formed around a centrally arranged PVC pipe with an OD of 7.5 cm, the fibers being placed in an annular zone around the centrally arranged holder and the radial width of the annular zone being approximately 7.5 cm, so that the strand's AD is approximately 11.25 cm.

In a first test, air is in initiated the strand; in a second test, air is circulated around the Led around the periphery of the strand. When the equilibrium is reached, the surgery is typically completed in selected Time intervals of back pulsing the strand continued with permeate, the interval depends on how quickly the fibers become so dirty that the electricity is essential is reduced.

The process conditions, which were kept constant over the test period, were as follows: TSS 17 g / l Biomass temperature 10.5 ° C Air flow rate 0.2124 m ³ / min. Suction height on the fibers 25.4 cm Hg

With external ventilation: a perforated flexible Tube with holes with a diameter of approximately 3 mm, spaced approximately 2.5 cm apart were wound around the base part of the ZW 72 strand and such oriented that air is discharged in a horizontal plane, so that bubbles enter the strand from the side between the fibers. Then the bubbles rise vertically through the strand fibers. The Discharge through the side helps keep the holes from clogging prematurely to protect.

With internal ventilation: The one in the middle tubular Bracket was used as a central air distribution manifold Conducting air in five 4 "sections of a 1/4 "tube with in 1 "intervals arranged 1/8 "holes used on one End are closed with a stopper and arranged with the center Pipe in open fluid connection, creating a spoke-like Injection tube is formed in the fiber on the base part. The number of holes it's about equal to the number in the external ventilation device, and the flow rate the air is the same. As before, air flows inside the strand sideways out of the holes off, and the air bubbles rise vertically within the strand above and leave the strand below the top header.

19 shows a graphical representation of the current as a function of time until the current reaches an equilibrium value. Thereafter, the current can be maintained by back pulsing at regular intervals. The plot shows that the equilibrium current with external ventilation is approximately 2.6 LMH, while the current with internal ventilation is approximately 9.9 LMH, which is approximately a fourfold improvement. From what has been said above, since it is known that the flow is a function of the flow rate of the air, with all other conditions being the same during normal operation, a greater flow is achieved with internal ventilation with the same flow of air.

Example 4

Comparison of the strands, one back and forth has movable fibers and the other one does not:

The relaxed state of the fibers is reduced by reducing the distance between the head elements set. The fibers are essentially not relaxed (the fibers are tensioned) when the head members are spaced apart by a distance equal to the length of a fiber between its opposed, cast ends. A single strand of ZW 72 with a nominal area of 6.7 m ² is used for each test in a bioreactor for treating waste water contaminated with ethylene glycol. Ventilation like in 9 shown (no internal ventilation) with side discharge of air bubbles into the strand fibers through which the bubbles rise upwards is provided.

In the first test, the headers are vertically spaced apart so that the fibers are stretched and can't move in there.

In the second test, the head elements approached each other by 2 cm, which resulted in a 2.5% sag in each fiber, so that the relaxed fibers could move back and forth.

As before, the process conditions that were kept constant over the test period were as follows: Solid suspended matter 17 g / l Biomass temperature 10.5 ° C Air flow rate 0.2124 m ³ / min. Suction height on the fibers 25.4 cm Hg

20 shows a graphical representation of the current as a function of time until the current reaches an equilibrium value. The current can then be maintained by back-pulsing at regular intervals, as previously in Example 3. The plot shows that the equilibrium current without back and forth is about 11.5 LMH, while at 2.5% sag it is about 15.2 LMH, which is an improvement of about 3%.

Example 5

Filtration of water with a vertical cylindrical strand for obtaining clarified water:

It becomes a cylindrical strand, as in 16 shown, made with 180 cm long Zenon ^® MF200 fibers, which form a surface area of 25 m2 in cylindrical head elements with a diameter of 28 cm, which are formed in end caps with an OD of 30 cm. Aeration is carried out with a spider-shaped device with perforated cross-shaped arms in which openings with a diameter of 3 mm (0.125 ") are provided, through the air in an amount of approximately 10 liters / min. (20 scfm, standard ft .) emerges ³ / min. This fiber is used in four typical applications, and the results are shown below. in each case, permeate is withdrawn with a centrifugal pump having a NPSH of about 0.3 bar (10 "Hg), and if equilibrium is reached, the strand is backwashed with permeate every 30 minutes for 30 seconds.

• A. Filtration of the water surface (pond) with 10 mg / l TSS: Result - permeate with 0.0 mg / l TSS and a turbidity of 0.1 NTU is at a rate of 2000 liters / hour. (LPH) taken. A "5 log" reduction (reduction the original concentration by five Orders of magnitude) of bacteria, algae, giardia and cryptosporidium can be achieved so that drinking water is preserved.
• B. Filtration of raw sewage with 100 mg / l TSS. Result - permeate with 0.0 mg / l solid suspended matter and a turbidity of 0.2 NTU with a Rate taken from 1000 LPH (liter / hour). Several such strands can comprehensive treatment of industrial wastewater in one Group can be used.
• C. Filtration of a mineral suspension with 1000 mg / l TSS iron oxide particles: Result - permeate with 0.0 mg / l solid suspended matter and a turbidity of 0.1 NTU with a Rate taken from 3000 LPH (liter / hour). A big stream is maintained with industrial waste water containing mineral particles.
• D. Filtration of fermentation broth with 10,000 mg / l bacterial cells: Result - permeate with 0.0 mg / l solid suspended matter and a turbidity of 0.1 NTU with a Rate taken from 1000 LPH (liter / hour). The broth with a high biomass concentration becomes non-destructive filtered to the one you want Generate permeate and save living cells for reuse.

Example 6

Mini strand for special purposes:

The following examples show the use of a mini strand for typical specific applications such as B. Filtration of (i) raw sewage to obtain solid-free water samples for colorimetry cal analyzes, (ii) surface water for use in a recreational vehicle ("camping vehicle) or caravan, or (iii) water from a small aquarium for fish or other marine animals.

A cylindrical mini strand is like in 16 as shown, with cylindrical headers having a 5 cm (2 ") OD and a 2 cm (0.75") thickness and 30 fibers, each 60 cm long, covering an area of 0.1 m ² to build. The strand is attached to a base part, on which a fan for discharging air in an amount of 15 l / min. at 12 kPa (3 psi) is removably mounted through a blow pipe with 1.6 mm (0.0625 ") orifices, with air flowing up the fibers along the strand. Furthermore, a peristaltic pump that draws a vacuum from 0.3 bar (10 "Hg) generated, detachably mounted on the base part. For each application, the independent strand with the integral permeate pump and gas discharge device for operation is placed in a cylindrical container with the substrate to be filtered.

The achieved with every application Results (A) - (D) are listed below:

• (i) The raw sewage contains 100 mg / l TSS; Permeate with 0.0 mg / l TSS and a turbidity of 0.2 NTU is withdrawn at a rate of 0.1 LPH.
• (ii) The extracted aquarium water contains 20 mg / l TSS, including Al faecal dendrite; Permeate with 0.0 gene, bacteria, fungi and mg / l TSS and a turbidity of 0.2 NTU is withdrawn at a rate of 0.1 LPH.
• (iii) The extracted pond water contains 10 mg / l TSS; Permeate with 0.0 mg / l TSS and a turbidity of 0.2 NTU is withdrawn at a rate of 0.1 LPH.

GLOSSARY

"Array"

– mehrere im wesentlichen vertikale Fasern von im wesentlichen gleicher Länge, wobei die einen Enden der Fasern nahe beieinander liegen, und zwar entweder linear in Querrichtung (hier die y-Achse), um mindestens eine Reihe und typischerweise mehrere Reihen äquidistanter Fasern zu bilden. Weniger bevorzugt ist eine Vielzahl von Fasern, die in einem willkürlichen Muster beabstandet angeordnet sind. Die einander gegenüberliegenden Enden der Fasern sind in einander gegenüberliegenden Kopfelementen abgedichtet, so dass das Substrat Permeat, das sich in einer Permeat-Auffangeinrichtung befindet, in welcher die Kopfelemente an der Peripherie abgedichtet sind, nicht verschmutzt.

"Bündel"

– mehrere Elemente, die zusammengehalten werden, z. B. mehrere Arrays, bei denen es sich um einen Stapel planarer Arrays oder bogenförmiger oder kreisförmiger Arrays oder eine aufgerollte Spirale handelt.

"Gruppe"

– wird der Kürze halber verwendet, um eine Gruppe von Strängen zu bezeichnen; in der Gruppe ist eine Reihe (oder andere Konfiguration) unterer Kopfelemente direkt unterhalb einer Reihe oberer Kopfelemente angeordnet.

"Zylindrischer Strang"

– ein vertikaler Strang, bei dem die Permeat-Auffangeinrichtung eine zylindrische Konfiguration aufweist.

"Tank, der auf einer Seite geschlossen ist"

– Tank oder Bioreaktor, aus dem keine andere Flüssigkeit als Permeat entnommen wird.

"Fasern"

– der Kürze halber verwendet, um Hohlfasermembranen zu bezeichnen.

"Strom"

– Strömungseinheit (Liter/Std.) durch eine Membran mit einer Flächenbereichseinheit (Metern), der Strom ist in Lm²h oder LMH angegeben.

"Flüchtiges Material"

– Material, das entweder (i) in einem Medium löslich ist, in dem die Fasern und das Fixiermaterial nicht löslich sind, oder (ü) dadurch fluidisierbar ist, dass es einen Schmelzpunkt hat (wenn das Material kristallin ist), der unter demjenigen liegt, bei dem die Fasern oder das Fixiermaterial beschädigt werden könnten; oder das Material hat eine Glasübergangstemperatur Tg (wenn das Material nicht kristallin ist), die unterhalb derjenigen liegt, bei der die Fasern oder das Material/die Materialien, die das nichtflüchtige Kopfelement bilden, beschädigt würden; oder (iii) sowohl löslich als auch fluidisierbar ist.

"Kopfelement"

– fester Körper, in dem einer der Anschlussendbereiche jeder Vielzahl von Fasern in dem Strang abdichtend befestigt ist, um zu verhindern, dass das Substrat das Permeat in den Lumen der Fasern verschmutzt. Der Körper mit beliebigen Abmessungen ist aus einem Natur- oder Kunstharzmaterial gefertigt (thermoplastisch oder wärmehärtbar).

"Einstückig ausgebildetes Kopfelement"

– Kombination aus Kopfelement und Permeat-Auffangeinrichtung, bei der das Kopfelement an der Peripherie fluiddicht mit der Permeat-Auffangeinrichtung verbunden ist.

"Einstückig ausgebildeter Einzelstrang"

– ein Strang in einem einstückig ausgebildeten fertigen Kopfelement ist in der Permeatwanne oder Endkappe ausgebildet, wobei das Kopfelement darin abgedichtet wird.

"Ministrang"

– selbständige gasgewaschene Anordnung eines Strangs mit einem Flächenbereich von weniger als ungefähr 5 m² in Kombination mit einem einstückig damit ausgebildeten Gasgebläse und einer einstückig damit ausgebildeten Permeatpumpe.

"Mehrkomponenten-Flüssigprodukt"

– zu klärende oder konzentrierende Fruchtsäfte; Abwasser oder partikelhaltiges Wasser; proteinhaltige flüssige Molkereiprodukt, wie z. B. Käsewasser oder ähnliches.

"Nichtvakuumpumpe"

– erzeugt eine erforderliche saugseitige Druckdifferenz oder eine erforderliche Zulaufhöhe (NPSH), die ausreicht, um den unter Betriebsbedingungen erzeugten Transmembran-Differentialdruck bereitzustellen; sie kann eine Zentrifugal-, Rotations-, Querstrom- oder Durchflusspumpe oder ein anderer Pumpentyp sein.

"Permeabilität"

– Strom pro Druckeinheit, Lm²h/kPa; manchmal als spezifischer Strom bezeichnet.

"Permeat-Auffangeinrichtung"

– Auffangbehälter unter einem Kopfelement, in dem sich Permeat ansammelt.

"Ring-Kopfelement"

– Kopfelement mit zylindrischer Form.

"Rechteckiger Strang"

– vertikaler Strang, bei dem die Permeat-Auffangeinrichtung die Konfiguration eines rechteckigen Parallelepipeds aufweist.

"Strang"

– der Kürze halber verwendet, um entweder einen zylindrischen Strang oder einen vertikalen Strang oder beides mit mehreren Arrays zu bezeichnen, die in einander gegenüberliegende Kopfelemente eingegossen sind, wobei die Fasern eine kritisch definierte Länge relativ zu dem vertikalen Abstand zwischen den Kopfelementen des Strangs aufweisen. Die definierte Länge begrenzt die Bewegung der Fasern von ei ner Seite zur anderen in dem Substrat, in das sie eingesetzt sind, außer in der Nähe der Kopfelemente, in der nur eine vernachlässigbare Bewegung erfolgt.

"Strangfasern"

– Fasern, die den zylindrischen Strang bilden.

"Vertikaler Strang"

– integrierte Kombination aus Strukturelementen mit (i) einer Vielzahl von vertikalen Fasern von im wesentlichen gleicher Länge; (ii) zwei Kopfelementen, in die jeweils die einander gegenüberliegenden Anschlussbereiche der Fasern derart eingegossen sind, dass ihre Enden offen bleiben; und (iii) einer Permeat-Auffangeinrichtung, die an der Peripherie in fluiddichtem Eingriff mit jedem Kopfelement gehalten wird, um Permeat von den Enden der Fasern aufzufangen.

"Substrat"

– Mehrkomponenten-Flüssigprodukt.

"Partikel"

– filtrierbares Material mit einer Größe im Mikronbereich (von 1 bis ungefähr 44 μm) und Submikronbereich (von ungefähr 0,1 μm bis 1 μm), das nicht nur anorganische Partikel enthält, sondern auch tote und lebende biologisch aktive Mikroorganismen, Kolloiddispersionen, Lösungen aus großen organischen Molekülen, wie z. B. Fulvosäure und Huminsäure, und Ölemulsionen.

"Eingeschränkt hin und her bewegbar"

– das Ausmaß, in dem sich Fasern in einer beschränkten Zone hin und her bewegen können, wobei das Ausmaß von der freien Länge der Fasern relativ zu den in festem Abstand zueinander angeordneten Kopfelementen und der Turbulenz des Substrats bestimmt wird.

"Array-Stapel"

– mehrere Reihen von Arrays, die dicht gepackt sind, um nach dem Eingießen einen Strang zu bilden.

"Im wesentlichen konzentrisch"

– beschreibt die Konfiguration, bei der einzelne Fasern entweder vertikal und beabstandet entlang dem Umfang eines um die vertikale Mittelachse gezogenen Kreises angeordnet sind, oder spiralförmig angeordnete aufeinanderfolgende Faserschichten, die typischerweise in der x-y-Ebene nahe beieinander liegen und nicht nur von der Mittelachse aus radial nach außen verlaufen, sondern auch entlang der Spirale in dieser Ebene, so dass sie in immer größer werdenden radialen Abständen zu der Mittelachse konzentrisch verteilt erscheinen.

"Transmembran-Differentialdruck"

– Druckdifferenz über eine Membranwand, die von den Prozessbedingungen hervorgerufen wird, unter denen die Membran arbeitet.

"Nicht gehalten"

– nicht gehalten, mit Ausnahme der Beabstandungseinrichtung zum Beabstanden der Kopfelemente.

"Vakuumpumpe"

– kann eine Ansaughöhe von mindestens 75 cm Hg erzeugen.

"Beschränkungszone" (oder "Blasenzone")

– eine Zone, durch die Blasen entlang den Außenflächen der Fasern nach oben steigen. Die Blasenzone wiederum wird von einer oder mehreren Säulen aus vertikal nach oben steigenden Blasen bestimmt, die nahe dem Basisteil eines Strangs erzeugt werden.

The following glossary lists the terms in approximately the order in which they are used in the description to define their meaning in the context in which they are used.

"Array"

A plurality of substantially vertical fibers of substantially the same length, the one ends of the fibers being close together, either linearly in the transverse direction (here the y-axis) to form at least one row and typically several rows of equidistant fibers. Less preferred is a plurality of fibers spaced in an arbitrary pattern. The opposite ends of the fibers are sealed in opposite head elements so that the substrate permeate, which is located in a permeate collecting device in which the head elements are sealed at the periphery, does not become dirty.

"Bunch"

- several elements that are held together, e.g. B. multiple arrays, which are a stack of planar arrays or arc-shaped or circular arrays or a rolled-up spiral.

"Group"

- is used for brevity to designate a group of strands; in the group, a row (or other configuration) of lower headers is located directly below a row of upper headers.

"Cylindrical strand"

- A vertical strand in which the permeate collector has a cylindrical configuration.

"Tank that is closed on one side"

- Tank or bioreactor from which no liquid other than permeate is removed.

"Fibers"

- used for brevity to refer to hollow fiber membranes.

"Electricity"

- Flow unit (liters / hour) through a membrane with a surface area unit (meters), the current is given in Lm ² h or LMH.

"Volatile material"

Material which is either (i) soluble in a medium in which the fibers and the fixing material are not soluble, or (ü) is fluidizable by having a melting point (if the material is crystalline) which is below that , which could damage the fibers or the fixing material; or the material has a glass transition temperature Tg (if the material is not crystalline) which is below that at which the fibers or the material (s) forming the non-volatile head element would be damaged; or (iii) is both soluble and fluidizable.

"Header"

Solid body in which one of the terminal end portions of each plurality of fibers in the strand is sealed to prevent the substrate from contaminating the permeate in the lumens of the fibers. The body with any dimensions is made of a natural or synthetic resin material (thermoplastic or thermosetting).

"One-piece head element"

- Combination of head element and permeate collecting device, in which the head element is fluid-tightly connected to the permeate collecting device at the periphery.

"Single-strand single strand"

- A strand in a one-piece finished head element is formed in the permeate trough or end cap, the head element being sealed therein.

"Mini-skein"

- Independent gas-washed arrangement of a strand with a surface area of less than approximately 5 m ² in combination with a gas blower formed integrally therewith and a permeate pump formed integrally therewith.

"Multicomponent liquid product"

- fruit juices to be clarified or concentrated; Waste water or water containing particles; protein-containing liquid dairy product, such as. B. cheese water or the like.

"Not vacuum pump"

- generates a required suction-side pressure difference or a required inlet height (NPSH) which is sufficient to provide the transmembrane differential pressure generated under operating conditions; it can be a centrifugal, rotary, cross-flow or flow pump or another type of pump.

"Permeability"

- Current per pressure unit, Lm ² h / kPa; sometimes referred to as a specific stream.

"Permeate collection means"

- Collection container under a head element in which permeate accumulates.

"Ring header"

- Head element with a cylindrical shape.

"Rectangular Strand"

- Vertical strand in which the permeate collector has the configuration of a rectangular parallelepiped.

"Strand"

- For brevity, used to refer to either a cylindrical strand or a vertical strand, or both, with multiple arrays molded into opposing headers, the fibers being of a critically defined length relative to the vertical distance between the headers of the strand. The defined length limits the movement of the fibers from one side to the other in the substrate in which they are inserted, except in the vicinity of the head elements, in which there is only negligible movement.

"Skein fibers"

- Fibers that form the cylindrical strand.

"Vertical strand"

Integrated combination of structural elements with (i) a plurality of vertical fibers of substantially the same length; (ii) two head elements, into each of which the opposite connection regions of the fibers are cast in such a way that their ends remain open; and (iii) a permeate trap which is peripherally held in fluid tight engagement with each head member to trap permeate from the ends of the fibers.

"Substrate"

- Multi-component liquid product.

"Particle"

- Filterable material with a size in the micron range (from 1 to approximately 44 μm) and submicron range (from approximately 0.1 μm to 1 μm), which not only contains inorganic particles, but also dead and living biologically active microorganisms, colloid dispersions, solutions large organic molecules such as B. fulvic acid and humic acid, and oil emulsions.

"Movable back and forth with restrictions"

The extent to which fibers can move back and forth in a restricted zone, the extent being determined by the free length of the fibers relative to the head elements arranged at a fixed distance from one another and the turbulence of the substrate.

"Array stack"

- several rows of arrays, tightly packed to form a strand after pouring.

"Essentially concentric"

Describes the configuration in which individual fibers are either arranged vertically and spaced along the circumference of a circle drawn around the vertical central axis, or spirally arranged successive fiber layers, which are typically close together in the xy plane and not only radially from the central axis run outwards, but also along the spiral in this plane, so that they appear concentrically distributed at ever increasing radial distances from the central axis.

"Transmembrane pressure differential"

- Pressure difference across a membrane wall, which is caused by the process conditions under which the membrane works.

"Not held"

- Not held, with the exception of the spacing device for spacing the head elements.

"Vacuum pump"

- can generate a suction height of at least 75 cm Hg.

"Restriction zone" (or "bubble zone")

- a zone through which bubbles rise up along the outer surfaces of the fibers. The bubble zone, in turn, is defined by one or more columns of vertically rising bubbles created near the base of a strand.

Claims (4)

A head element and permeate collection device, the cast hollow fiber membranes ( 12 . 112 . 212 ), the head element and permeate interception device having the following features: a) a solid mass of a casting material which has a first surface; b) a plurality of hollow fiber membranes ( 12 . 112 . 212 ) included in the molding material; and f) end sections ( 12 " . 12b " . 212 ' . 212b " ) of the hollow fiber membranes ( 12 . 112 . 212 ), the end sections ( 12 " . 12b " . 212 ' . 212b " ) are adjacent to open ends of the membranes and protrude from the first surface, characterized in that g) the solid mass of casting material extends towards the inner periphery of the permeate collecting device ( 20 . 102 . 120 . 120b ) extends and is adhesively attached thereto to form a permeate collection zone; and h) the end sections ( 12 " . 12b " . 212 ' . 212b " ) protrude into the permeate collection zone with the open end of the hollow fiber membranes. The head member of claim 1, wherein the solid mass of molding material is facing the inner one Periphery of a permeate crucible ( 20 . 102 . 120 ), an end cover or a head element surround ( 120b ) extends and is adhesively attached to the same to form the permeate collection zone. The head element according to claim 1 or 2, which has a damping layer which the fibers ( 12 . 112 . 212 ) embedded, the damping layer adhering to and covering the casting material. The head element according to claim 3, where the damping Layer a hardness in the range from Shore A 30 to Shore D 45.