WO2008000306A1

WO2008000306A1 - Stacked hollow fiber module

Info

Publication number: WO2008000306A1
Application number: PCT/EP2007/000979
Authority: WO
Inventors: Hardy Lapot
Original assignee: Hardy Lapot
Priority date: 2006-06-27
Filing date: 2007-02-06
Publication date: 2008-01-03
Also published as: DE102006029426A1

Abstract

The invention relates to a capillary module or hollow fiber module for filtering and separating liquids in dead-end and/or cross-flow operation, the arrangement thereof in an entire technical system, and the operation thereof. The inventive capillary module or hollow fiber module is easier to clean as the same comprises external boxes that are easy to open while facilitating the introduction of liquids and/or gases. The inventive external permeate chambers make it easier to locate and repair defective capillaries. Furthermore, backflushing is more effective, the separation result is more accurate, and there are no indefinable dead zones in the fiber bundle, which render cleaning more difficult and promote germ formation.

Description

HOLLOW FIBER TAPE MODULE

The present invention relates to a capillary or hollow fiber module for the filtration and separation of liquids in dead-end and / or cross-flow operation, its arrangement in a process engineering system and its operation with the features of the preamble of claim 1.

State of the art

In the field of membrane-technical treatment of liquids, gases or liquid-gas mixtures, various capillary membrane systems have become established in wide areas of application technology. Other methods than the use of capillary modules play in areas such. As the water technology, beverage technology or sewage treatment technology a rather minor role. In the areas in which the capillary membrane can "play out" its many advantages, this membrane configuration is primarily used.

Within the scope of the discussion in this document, therefore, capillary modules should be dealt with exclusively. This is for the reason that in such large applications such. As the water technology, wastewater technology, beverage technology, biotechnology and gas technology, the capillary membrane is already a firmly integrated and accepted process engineering component and in these areas is an enormous growth potential of membrane technology.

In this document, capillary is used as a collective term for the terms commonly used in practice hollow fiber, capillary and tube and covers tubes / tubes with an inner diameter of about 0.1 to about 250 mm, usually those with about 0 , 3 to about 6 mm can be used. The wall of the tubes / tubes is always a more or less permeable membrane, which is reinforced in some embodiments by a substrate or by tissue.

Capillary modules are used in the art for filtration, separation, diffusion, pervaporation, dialysis, and other separation techniques. Bioreactors are also manufactured on the basis of capillary modules. The advantages of a capillary module are, above all, the low risk of clogging, the ability to backwash, the compactness of the modules and the relatively low production costs.

In the prior art, various embodiments of modules are well known. Despite many advantages, however, all module designs also have significant disadvantages that limit their applicability and reduce the efficiency.

The original and hitherto largely conventional form is that in which a bundle of capillaries which are open on both sides is introduced into a tubular housing and cast at both ends. The fluid to be treated is pressurized by the

Pumped capillaries, the permeate passes through the capillaries and is in the

Gaps collected and removed from the surrounding pipe.

Further developments turn this principle around, so that now in a similar housing, the capillaries are flowed from the outside and permeate is discharged through the interior of the capillaries. In this case, the driving force can be either pressure on the outside of the capillaries or a negative pressure in the interior thereof.

The two configurations mentioned have significant disadvantages, which drove the development of the so-called submerged systems. In principle, capillary bundles without housing are immersed in liquid. The driving force is usually a negative pressure applied on the inside, or also an externally applied pressure (liquid level in the immersion tank) or a combination of both.

To better illustrate the state of the art, Fig. 6 is intended to serve. In this module, all modules currently in commercial use in the market are grouped according to their functional principle. Z is supply, R is retentate outlet and P is permeate outlet.

In module group A, products are summarized in which the fluid feed takes place at one end on one end and the retentate discharge on the other end at the end. The flow of the fluid to be processed takes place inside the capillaries. The

Permeate discharge takes place via a connection on the module housing. In general, will be several such modules are arranged in parallel in so-called racks. The modules are usually flowed from below. In many applications (such as beverage technology or oil-water separation), this modular design and mode of operation is chosen. It is usually driven with higher "loaded" media in cross-flow mode.

In module group B, products are grouped together that are identical to those of group A, but run in dead-end mode. Retesting usually takes place only sporadically or to such an extent that no appreciable flow prevails inside the capillaries. As a rule, several such modules are also arranged in parallel racks. Again, the flow is usually from below. This modular design and mode of operation is used for relatively low loaded media (such as drinking water).

In the module group C products are summarized, which are indeed similar to those of the groups A and B, but the principle is reversed, so that the capillaries are flowed through from outside to inside of permeate. The supply fluid enters the module at one end of the housing, flows around the capillaries from the outside and leaves the housing via a connection on the circumference of the housing tube. The permeate exits at the other end of the housing. Also in this type several modules are arranged in parallel in racks. The flow always takes place from below. This module family can be used for mediocre media (such as wine or sewage treatment plant effluent).

In module group D, products are compiled that are identically structured as those of group C, but are operated in dead-end mode. The construction of such modules also takes place in parallel in so-called racks. The flow is always from below. The applications for such modules are in areas such as those of Group B. With regard to the mode of operation, however, the difference is that one works with more frequent retentate side flushes and drains.

Group E includes products that are also referred to as "submerged" modules. They are immersed without external housing in the liquid to be filtered (fluid) and can only be operated in the dead-end process. Such modules can be used both for low-load (eg drinking water) and for very high-loaded Media (eg, activated sludge) can be used as the capillaries are moved and "purged" by a stream of blown in and rising air bubbles. The capillaries are arranged vertically and cast in one or both sides.

Module group F comprises products that are also immersed in the medium to be processed and operated only in the dead-end process. However, the capillaries are arranged horizontally. These modules can only be used in liquids that have been freed of coarse and fibrous material. They are also moved with an ascending air bubble stream and "cleaned".

The terms used below are to be understood as follows: The filtrate direction designates the flow direction of the permeate through the wall of the capillary. This can be done from the inside to the outside, wherein the filtering layer is then located on the inner surface of the capillary. The Filtratrichtung can also be done from the outside in, in this case, the filtering layer is to be found on the outer surface of the capillary. Furthermore, there are capillaries that are constructed in two layers.

In some types of modules, capillaries are housed in a pressure housing and are usually poured in at both ends. Capillaries can also lie freely in the medium without pressure housing.

To "push" or "pull" permeate through the membrane and capillary wall, a "driving force" is required. This can be a pressure above or below atmospheric pressure.

Capillary modules can be operated in the dead-end or in the cross-flow method. In dead-end operation, the driving pressure force is applied to the capillary without it being significantly overflowed. During cross-flow operation, there is a significant overflow, which is suitable for removing deposits on and a covering layer on the membrane surface or keeping it low.

Room space requirement is the space required by the membrane surface of several modules in the installed state (rack). The space requirement is given in m ² / m ³ .

The expenditure of energy arises essentially either by the pumps necessary for cross-flow circulation or by the feed pumps at Dead-end operation or by feed pumps and gas supply in submerged systems.

It is important to ensure a uniform flow of capillaries in the module, so that all can perform the same performance, do not occupy irregular and can be cleaned equally well. The degree of capillary stress arises on the one hand due to the flow of the capillaries and on the other hand due to mechanical movement.

The average transmembrane pressure (TMP) represents the driving force already mentioned. Note also the margin between TMP at the module entrance and TMP at the module exit.

If the medium always flows in a certain direction, there is the danger that "directed" deposits build up on the membrane and attach accordingly in the roughness of each membrane and on the same. With a periodic flow reversal this effect can be counteracted. Each membrane system is to be cleaned from time to time. It is important for the lasting good function of a plant that the cleaning is effective and easily possible.

Backwashing is performed so that periodically a clean fluid (usually permeate) is forced from the permeate side of the membrane to the retentate side. This serves the purpose of "lifting off" deposits on the membrane, thus keeping the top layer low and the performance high. Dead-end modules often use a so-called fast-flush method. This is understood to mean the brief full opening of the retentate outlet in order to push out the concentrated module contents and to achieve a certain top layer degradation.

The integrity of the capillaries is tested by means of an integrity test. Usually a pressure holding test is carried out. If the pressure hold test is positive, this means that one or more defective capillaries are present in an assembly of modules (usually a rack) or in a single module. If the integrity test detects that defective capillaries are present, the task is to find out which and where they are. The usual methods for this task are the air bubble test or the "fountain test" on the single module. For a good process control, it is also important that the capillaries in a module have a chosen arrangement and also retain. An accidental arrangement or one that may change significantly during operation is not favorable.

Retentate-side dead zones are zones in the capillary bundle, which are insufficiently flown in one or more modes of operation. The same applies to permeation dead zones.

Of crucial importance for the cost per m ² membrane area of a module is in addition to a cost-effective membrane production and the cost-effective production of the module itself. Here, in turn, the automation of the production is crucial.

It is crucial how easy or difficult the operation of a module in an overall system is and how procedurally simple or complex a system with modules of a certain type can be built.

In the following table, the individual module groups characterized above are evaluated and characterized according to the criteria presented.

Summing up the assessments of the state of the art and reducing them to the most important points, the following picture emerges: All systems have a relatively high space requirement. In the case of modules of groups A to D, this is due to the fact that each module is relatively short (in industrial plants lengths of 1 to 1.5 m are usual) and has a relatively small membrane area (usually 5-60 in industrial installations) m ² ). If such modules are installed in parallel with required intermediate distances in a rack, so there is disadvantageous a large footprint and a very low height. In the case of the modules of group E and F, the unfavorable space requirement results from the installation in relatively low basins with intermediate and lateral distance between the modules and the basins.

Inflow or flow around the filtering membrane: Especially in the module groups C to F, the capillaries are poorly flown on the retentate side because of the random bundling of the capillaries. On the permeate side, this applies in particular to the modules of groups A to D. This leads to a number of disadvantages. The membrane surfaces are loaded differently. This results in a different cover layer structure, which in turn causes a different separation characteristic. The retentate-side dead zones represent "wasted" membrane surface. It is difficult to clean the capillaries. To clean the capillaries frequent backwashing is necessary, resulting in yield and time losses.

Another disadvantage is the high capillary stress. Especially with submerged modules, the capillaries tire over time due to the constant movement caused by the air bubble flushing. For pressure-operated modules, the tensile stress on the capillaries due to the pressure drop across the length of the capillary must be taken into account. This leads to short membrane life and reduced efficiency. Furthermore, there is the danger of membrane breakthroughs and flaking, whereby microorganisms, pollution, etc., get on the permeate side and can contaminate the permeate. The disadvantages mentioned require a high maintenance and lead during the maintenance time to production restrictions.

Particularly in the case of the pressure-operated modules with high flow velocity in the capillary but also in the modules operated at relatively low pressure, the span of the transmembrane pressure (TMP) is high, which leads to an uneven deposition of a cover layer along the capillary length. To prevent this, frequent flow reversal circuits (if this is possible at all) and frequent backwashes are required, which in turn results in a loss of yield and time. The backwashing often only leads to uneven effects, so that the capillaries continue to be cleaned frequently. As a result, costs for cleaning chemicals arise, in addition, there is a loss of production during this time. The disadvantages mentioned lead to a high plant engineering effort.

Fast-flushing and backwashing are limited or even impossible with some module systems. A major disadvantage of all modules listed is still that finding and repairing defective capillaries means a lot of maintenance and involves the risk that defective capillaries can not be detected at all.

In none of the modular systems listed in the prior art, an ordered capillary arrangement is realized. This results in a whole series of disadvantages. The arrangements have dead zones both on the retentate side and permeate side. Due to the poor flow of the capillaries, frequent backwashing and / or cleaning must be carried out. Furthermore, there is a risk of microbial growth and non-reversible blocking in the dead zones. All these disadvantages lead to performance limitations and a deterioration of the economy.

Simple operation is not possible with most modular systems because of the complexity of plant construction required to install, drive, backwash, clean, test for integrity, and so forth on many relatively small modules. The development of the modules of the groups E and F was already an important step compared to the modules of the groups A to D, but only for the applications in which modules of the groups E and F can be used at all. To be listed here are by way of example DE29624474, DE20300546 and JP11147028. In these and similar writings the idea of submerged capillary membranes is documented. At an early stage, attempts were also made to completely eliminate the many disadvantages listed above. With this goal, various frame and cylindrical modules have been developed. For example, in DE1642811 capillaries have been integrated into plates. A similar approach is followed by DE69516173. A further example can be found in DE2650341 in which the idea of stacked hollow fiber (capillary) layers has already been documented, the ends of which lie on the circumference of the module. DE4230194 also describes a module interior filled with capillaries. The capillaries end here in external rooms. However, the module is not "stackable" and therefore not suitable for large-scale industrial use A similar invention is US 4176069 with similar disadvantages EP350853 also shows capillary layers layered on top of each other, but in a round or polygonal frame, in an overall housing The arrangement can not be flowed through on the inside and a TMP (transmembrane pressure) is not controllable.So similarly US5182019 and EP0560720 are designed.The flowability is given here, but there is only one outer space.An individual setting of the TMP is here In a manner similar in itself, this is also to be found in EP 454918. DE19932439 has only one surrounding outer space The invention is not suitable for filtration use In DE3750497 a capillary module in plate-frame design is described be made with parallel capillaries and only with a maximum of two external rooms. All these systems still have serious disadvantages, which is why they have not prevailed except in the case of the immersed membrane technology in large-scale use and in the market.

DE10393754 represents a further development of the documents cited in the above-mentioned documents. However, the outer spaces are not provided for setting an advantageous TMP. The Permeatabgang is only on one or two sides and the cross-laying of capillaries within a frame is not planned. Furthermore, the capillaries are not accessible from the outside for inspection and repair. The invention does not provide for direct introduction of fluid into the capillary package. Individual module frames can not be combined into one module unit and operated with one external space per side. For all these and other reasons, it is therefore designed as a competitor to common small-scale flat-membrane cassettes and not for large-scale use in a procedural overall system

A capillary defect can be detected by a pressure holding test. Due to the closed design of the modules described above, however, it can not be found out which single capillary is defective. Consequently, in such a case, even if only one of thousands of capillaries is defective, the entire module must be replaced. Even then, a repair of a capillary is not possible because the system is closed. The largely intact module must be discarded.

Furthermore, it is not possible to shut down individual modules upon detection of a capillary defect. In the field of filtration of water, beverages and biotechnological liquids or the degermination of gases, however, this is absolutely necessary to ensure the microbiological quality and must be possible even if the production with the remaining modules continues.

A cleaning of the capillaries by means of a gas bubble stream is only possible in the known modules in such a way that the entire structure is flowed through the gas bubble stream from the very bottom to the very top. However, it is not possible to set uniform conditions over the entire height, since the gas bubbles increase in the upward direction due to the decreasing pressure. Particularly in the case of higher capillary layer stacks, in which several layers are arranged one above the other, they sag due to their own weight and are not stabilized. This leads to a tensile stress on the capillaries, especially at the cast-in ends.

It should also be noted that fluid can not be introduced directly into the capillary stack. A cleaning of capillaries caused thereby due to high local flow does not take place. Accordingly, a separate supply and discharge of fluids into or out of the capillary layer stack is not possible. Furthermore, in a large-scale plant, no concentration of the fluid to be treated to a small residual amount (corresponding to a high yield) is possible.

description

The object of the invention is a capillary or hollow fiber module for filtration and separation of liquids in the dead-end. or develop cross-flow method, which has neither the disadvantages of the hitherto commercially available module systems as well as the recent developments and at the same time gives no new disadvantages. The capillary or hollow fiber module according to the invention should be easier to clean, this is achieved inter alia by facilitating the introduction of liquids and / or gases. Furthermore, a simplified finding and repairing defective capillaries should be possible, the backwashing should work more effectively, the separation result should be more accurate, and indefinable dead zones in the fiber bundle, which make cleaning difficult and facilitate microbial contamination, should be avoided.

These objects of the invention are achieved with the subject matter of the independent claim. Features of advantageous developments of the invention will become apparent from the dependent claims.

The invention uses capillary membranes known in the art. The membranes can be made of any known material, for example polymer, ceramic, metal or other materials. Likewise, any available on the market capillary or Rohrmembrandurchmesser be used. Membranes with a filtering layer inside or outside or on both sides can be used.

The module according to the invention consists of a multi-layered capillary stack, as has already been described in principle in FR 15 47 549 and in FR 73 25 450. One layer consists of parallel capillaries. The underlying or overlying layer can also have directional capillaries or even those that extend at an angle to it. Preferably, the capillaries are one layer at 90 degrees to those of an adjacent layer.

In the module, several capillary layers are bordered on all sides to form a frame with capillaries in between. This happens in one in such a way that the capillaries of all or individual layers end open to the outside at least on one of the enclosed sides. Alternatively, the capillaries are bordered only at their two ends. The two remaining sides are formed in this case by a wall of sheet metal or plastic or the like and are fluid-tightly connected to the other two walls. The walls of z. B. sheet metal can also be performed wavy, so that they adapt to the shape of the capillaries.

If the stack of rectangular shape, it is provided side by side with potting and cured. This potting compound can consist of both conventional synthetic resins as well as of ceramic or other organic or inorganic materials. It is possible that on the side to be cast in each case a mold (lined inside possibly with non-adhesive coating) is "plugged" into which potting compound is then introduced, which has the advantage that the casting location can be defined and shaped more accurately and that the contact area can be chamfered to the left and right ends of the potting area, so as to provide more contact surface with the next potting area of the next side, which contact area can also be strengthened and improved before or after potting, by applying suitable materials. A suitable material is an absorbent fleece or net, but pin-shaped connecting parts are also conceivable, and it is also possible that the respective surface is coated with a suitable adhesion-improving chemical before a new casting action and reserved is changed.

If the stack is round in shape, the above steps are not necessary. In this case, the round stack is rotated in a bath of potting compound. Both in the rectangular and the round shape, a conventional spin process can be applied.

If necessary, then the top and bottom and possibly also the lateral potting compound surfaces can be ground flat and the outside, on which the capillaries are exposed, machined. This can be done, for example, by cutting off, sawing off, milling off, turning off, etc. In a further production variant of the module frame according to the invention, the individual capillary layers are not cast, but glued together. This can be done so that first a flat frame is placed with a certain height of a suitable material. Then an adhesive is painted, in which the capillaries are inserted. Over the capillaries now a band is laid, which corresponds in its width approximately to the width of the underlying frame. By lowering a stamp with the same footprint as the entire Kapillarla- stapel the position of capillaries is now pressed into the pasted onto the frame adhesive. The amount of adhesive is in this case dosed so that the space between the capillaries is filled during the process of compression. After the stamp has been pulled up again, adhesive is now applied to the tape above, capillaries are inserted, tape is placed on it and the stamp presses everything together again. This will continue until the complete stack. At the top of the pile, a frame is added last. Even with this type of module frame, the outsides are now in a known manner, for. B. by cutting, sawing, milling, turning off, etc., processed.

Due to the above-mentioned method steps, a module frame is produced with an inner, capillary layer stack through which fluid can flow. The frame is top and bottom plan. For round frames, the exposed capillaries are visible on the entire circumference, with rectangular frames on at least one, but also on all sides. Such module frames can now be further processed individually into modular units and / or assembled to form larger overall module units with a large membrane area.

So that the capillaries are easily accessible for the maintenance of the modules, the modules according to the invention contain so-called outer boxes. Namely, a box is pushed onto individual module frames and adhesively bonded or welded to the module frame in a fluid-tight manner. This creates a permeate space on each outside of a module frame. According to a further embodiment of the invention, it is also possible to insert such a box into a previously cut or milled groove in the potting / gluing compound, which is then glued or welded. Such boxes may be mounted on one or more sides of an entire module frame unit. The boxes can take different forms For improved flow, cleaning, and internal volume reduction, boxes with non-parallel surfaces and non-rectangular corners and edges are preferred.

A special feature of these outer boxes is that their outer surfaces can at least partially consist of a removable and closable lid and this is sealed liquid-tight at its edges. This cover may preferably be made of transparent material. Through this designed as a disc cover can be seen on the open ends of the capillaries of the module frame. During an integrity test, but also during operation, defective capillaries can be visually recognized through the window. In the case of a detected defect, the permeate of the respective module unit can be closed immediately. According to the invention, a motion detector can be installed in each of these permeate spaces which, during operation or during the integrity test, identifies any fountains that may emerge from individual defective capillaries and reports such a defect. The repair of a capillary recognized as defective takes place through the opened lid opening in which the ends of the corresponding capillaries are closed.

Furthermore, these permeate spaces can also contain process-technical connections through which liquid can be supplied to and removed from the outside or from other outer compartment boxes / permeate spaces. In addition, metrological connections can be provided which serve to record process and process engineering data.

According to a preferred embodiment, a module can be designed so that individual capillary layers only open open on one side of the module frame and thus also in different boxes open. One or more capillary layers can be replaced by so-called injection capillaries. This is understood to mean open (possibly of different lengths) or closed and perforated, slotted non-permeable capillaries provided with holes over their length, via which liquid can be introduced directly from outside into the capillary stack. So z. B. in the filtration of liquids periodically purge gas for generating air bubbles and for cleaning the surfaces of the capillaries are pressed or it is the introduction of chemical cleaning liquid for cleaning the membrane surfaces possible. These injection tubes end in a separate outside space. This liquid can be pressed directly into the permeate. This is z. B. desirable for the introduction of gas to clean the capillaries with gas bubbles or for the introduction of cleaning liquid directly to the capillaries. Due to this arrangement, liquid can be fed evenly and directly to the capillary stack. This possibility is z. B. also useful for the introduction of nutrient fluid in the capillary stack, when the invention is used as a membrane reactor.

The non-permeable injection capillaries used in the module and the permeable capillaries may have different inner and / or outer diameters. The non-permeable injection capillaries may have different lengths and may be made of plastic, ceramic, metal or any other material.

The capillary layers may consist of single capillaries or capillary bundles or of interwoven or otherwise made capillary mats. A capillary mat may consist of two layers of capillaries that are weave-like at an angle to one another, or else of a layer of capillaries, to which individual threads run transversely as a weft. In the manufacture of the membrane module, for example, two or more endless Kapillarmattenbahnen can be used, which are folded into one another at an angle to each other alternately.

In different layers (and sometimes also within a single layer) different capillaries can be used in terms of material, design, cut-off and diameter. To give the arrangement stability, single capillaries of a layer can be replaced by solid tension threads or tension mats.

The distances between the capillaries are defined in each position. The distances can be configured differently depending on the intended use within one layer, in different layers and / or in individual modules. The basic shape of a capillary in plan view may be round, oval, rectangular or polygonal. For reasons of cost-effective module and plant production, the rectangular shape is preferred.

In the production of a capillary, capillaries from the roll, individually cut to length capillaries, mat-processed fabric from the roll or pre-cut pieces may be used. The dimensions of the base of a Capillary position are down and up technical and economic limits set. The aim is dimensions of a few centimeters up to 2 meters edge length or diameter. The height of the stack of capillary layers can make up only a few capillary layers, but also many hundreds of them, so that stacks of z. B. one meter thickness are conceivable. A stack with capillaries of 0.8 mm outer diameter, a capillary distance of 0.4 mm, a flow-through base of 1 m ² and a thickness of 10 cm (125 capillary layers) has an active membrane area of about 260 m ² .

Individual layers under or in the layer stack, but also z. B. every other layer, may consist of mesh, latticed or fleece-like material or extending transversely to the course of the capillaries tension threads and serve the flow distribution and / or the stabilization of the stack and / or the spacing between capillaries. A layer of mesh, latticed or fleece-like material can according to the invention also represent the uppermost layer. In such a case, the material essentially serves as a flow distributor and prefilter to prevent contaminants from entering the stack, which can lead to blockages. Furthermore, to stabilize the capillary and layers of solid ribbons, yarns, fibers, wires, u. Ä. be integrated. Furthermore, to stabilize the capillary within a Kapillarlage individual capillaries can be replaced by wires, yarns threads.

The modules according to the invention can be divided spatially by means of partitions. For this, one or more intermediate walls are inserted transversely to the direction of the capillaries and between the frame-shaped sides of the module, which divide the interior of a module frame into two or more flow segments. The intermediate segments used may consist of sheet metal, perforated plate or another cast material.

If at least two single-frame modules are arranged above (vertical / vertical) or next to each other (horizontally / horizontally) and connected to each other, a so-called module unit is obtained. The connection between their individual modules can be reversible or fixed, the connection must be fluid-tight. At least two module units can in turn be fluid-tightly assembled via intermediate pieces to form a total module unit. A single frame module or also to a module unit superimposed interconnected frame modules can be provided with a lower and a top and operated so. This creates a so-called head and floor space. A larger unit is obtained by providing several modular units with intermediate pieces and a lower and a upper part. In both cases, this allows the flow through the capillary-filled inner channel of the unit thus created, wherein flow rate and pressure can be set very different depending on the application.

Individual module units are reversibly or irreversibly sealed against intermediate, lower and upper parts. This can be z. B. via bonding. For example, sealing over seals or via clip connections is also advantageous. A further and advantageous possibility according to the invention is the compression of the entire arrangement so that all seals seal tightly. The compression can be done manually via a mounted over the top spindle or automatically via a hydraulic device. It is also possible that at the corners of the arrangement of the modules threaded rods, which are connected via eyelets with the modular units, are attached, by means of which the entire assembly can be screwed together.

The intermediate pieces and the lower and upper parts may, if necessary, have process-technical connections for the supply and removal of liquids and metrological connections for process and process-related data acquisition. The intermediate piece and / or the lower part and / or the upper part in this case constitute a firmly integrated component of a module unit or a total module unit. The upper part and / or the lower part may be a closure plate, a frame, a tub or to trade a container part.

In the upper part or above each module, a trickling system can be attached, through which the capillaries can be charged with liquid. Furthermore, over at least one frame module, a coarse filtering layer may be attached, which serves as a pre-filter and safety filter. This filtering layer can be moved or pulled through a corresponding device so that it can be pulled away with the depositing solids on it. The deposited Solids are removed, so that the again unoccupied filter layer comes to rest again above the modules.

Within the overall module unit described above, it is also possible for at least two compartment boxes to be connected to one another via the outer boxes in such a way that they operate from inside to outside through the capillary in the cross-flow mode or in the dead-end mode can be. The retentate flows in this alternative embodiment of the invention in the lumen of the hollow fiber, the permeate flows into the spaces, which are interspersed with capillaries. Increasing the headspace above the topmost module increases the hydrostatic head so that its pressure as the driving force for filtration is sufficient. Furthermore, the supply pressure to the module assembly can be increased so that the pressure in the interior of the module assembly is sufficient for filtration. In the overall module unit described above, the transmembrane pressure (TMP) can be adjusted by appropriate throttling of the permeate valves so that each module of the assembly is applied approximately the same TMP.

In the total module unit described above, the liquid to be filtered can be introduced into all or only selected modules. In the total module unit, backwashing, rinsing and cleaning with gas, liquid or a mixture of both can be easily performed. It is advantageous here that these processes can take place simultaneously or overlapping.

The total module unit may be operated so that the flow direction of the permeate is both out-in (lumen-side suction or retentate-side pressure) and in-out (lumen-side pressure or retentate-side suction). The total module unit can be retentate as well as permeate side under pressure, so that it can come to any outgassing or gas release of a liquid to be filtered. Furthermore, the total module unit can be used as a membrane reactor, wherein nutrients are supplied to at least one module side and / or metabolites are withdrawn.

The replacement of individual frame modules or module units within a total module unit can be done easily and easily. The part of the arrangement above the module to be exchanged consisting of membrane modules, intermediate pieces and upper part, which are connected via threaded rods or the like. are raised so far that the underlying membrane module can be easily removed from the arrangement.

In the production of a layer stack it may be useful to avoid displacements of the individual capillaries to give the stack cohesion, in which this is soaked at least in some areas with a solidifying mass (eg., Strength, textile size o can be washed out again after production of the module frame or the frame module.

The overall module units can be used in a variety of ways in a process engineering design. In the case of the modular systems according to the invention, the following method steps can be selectively controlled: filtration operation, permeate withdrawal, backwashing, purification, module flushing (fast flush) and gas purging.

Furthermore, a simple integrity test is possible in which defective capillaries can be specifically identified. If the integrity test shows that there is a capillary defect in one of the modules, the module interior is slowly filled above the level of the relevant module. Also, with full interior pressure can be applied. Through the module window of the outer boxes can be seen from a certain liquid level or a certain pressure, as liquid escapes reinforced from one or more defective capillaries. In most cases, the increased fluid leakage will already be detected during ongoing controls during operation. The corresponding module can be isolated by detecting valve defects when defects are detected until the defective capillaries can be repaired.

If the defective capillary is identified, it will continue to leak liquid from the defective capillary. You open the corresponding window of the outside box and can now clog the open end of the capillary and thus shut down the capillary.

Further details can be found in the figure description to the figures 5a and 5b.

The invention thus has significant advantages over the prior art. Due to the very compact design of the module and the compact

Arrangement of the membranes is the space requirement for the invention Module arrangements very low. Since the module construction in the height, the footprint is extremely low and room heights can be optimally utilized. When using modules with a rectangular design also space can be saved.

The energy consumption for the modules according to the invention is in frequent gas purging in about the same amount as the energetically favorable submerged systems. In the system according to the invention, however, no or only a rare gas purging is required, so that the energy requirement is well below the needs of the submerged systems.

Due to the absolutely regular arrangement of the capillaries in each layer plane, the flow at each point of each capillary is absolutely identical. Furthermore, the tower-like structure favors the distribution of the medium.

The liquid supply can be done directly in the capillary stack. If the total quantity of liquid, corresponding to the amount of withdrawn permeate, is added within a module, then an advantageously high flow is generated therein, which has a cleaning effect. After a certain time, another module for the liquid supply can be switched and thus "cleaned" at the same time.

In the separation of liquids, a gas purging of the membrane surfaces is often advantageous. This can be done simply and very effectively so that purge gas is injected via injection capillaries directly into the Kapillarlagenstapel while a certain fluid circulation is operated. In this way, there is a very good and uniform flow over and cleaning of all Kapillaraußenflächen with purge gas bubbles.

The physical stress of the capillaries in the module according to the invention is very low, since they are arranged stably. Due to low flow rates during out / in operation, the traction effect of the pressure drop of the flowing medium is low. Furthermore, the capillaries do not move and there is no material fatigue.

In out / in operation, the range of transmembrane pressure (TMP) within a module is negligible. In the entire module arrangement, there is only a slight pressure difference between the top and bottom, and this is usually the case only to the hydrostatic pressure. By setting the permeate pressure, the optimum transmembrane pressure can be set for each module.

In the module according to the invention, a flow reversal is possible at any time, even during ongoing production. Cleaning is easy and effective because there are no restrictions and no dead zones. Each capillary can be easily primed and cleaned. The recirculation rate during cleaning can be easily changed and adjusted.

Furthermore, the backwashing is easily and effectively possible. It should be noted that the backwashing can be optimally supplied for the reasons already mentioned in "cleaning". Each capillary is flowed evenly and equally well from the backwash medium. By increasing the flow rate, the module can be operated quickly and easily in a fast-flush process. By changing the conveying direction, this is possible even in both directions.

The integrity test is easily possible in both directions through the capillary and can be carried out with both liquid and gases. Faulty capillaries can be found easily and, above all, during operation and without removing the module. This ensures optimal operational safety. If a capillary is identified as defective during operation, the corresponding module can be temporarily shut down by closing the permeate valves.

The capillaries are arranged in a defined manner. Within a shift, they run absolutely parallel. Individual layers are arranged at a predetermined angle to each other. Owing to the capillary arrangement according to the invention, the formation of dead zones is not possible both on the permeate side and on the retentate side.

The residual volume can be concentrated in the system. The liquid level can be lowered to the level of the lowest module.

Another important advantage of the modules according to the invention is that the module production can be easily automated.

In the modules described in the prior art also no intermediate layers for flow distribution and stabilization are provided. Furthermore, the fluid can not be introduced directly into the capillary layer stack. An associated cleaning of capillaries due to high local flow can not be exploited. A concentration of the residual volume in the plant in large-scale use, as well as a separate supply and discharge of various fluids in and out of the capillary stack is also not possible.

Fiqurenbeschreibunq

Further features, objects, and advantages of the present invention will become apparent from the following detailed description of a preferred embodiment of the invention, given by way of non-limiting example and with reference to the accompanying drawings. The same components in principle have the same reference numerals and will not be explained several times.

FIG. 1a shows a single-layer capillary course in north-south direction; FIG.

Fig. 1 b shows a single-layer capillary course in the west-east direction;

Fig. 1c shows the capillary course in two capillary layers, in the 90 °

Are arranged angle to each other;

Fig. 2a shows the schematic diagram of a module frame;

Fig. 2b shows the side view of a module frame;

Fig. 2c shows the top view of a module frame;

Fig. 2d shows a frame unit consisting of several superimposed module frame;

FIG. 3a shows permeatres formed as boxes which are plugged onto the module frames; FIG.

Fig. 3b shows formed as boxes Permeaträume which are inserted into the module frame;

Fig. 3c shows a side view of a module frame with attached

Permeatraumkasten;

Fig. 3d shows a frame unit consisting of three superimposed module frame with inserted Permeatraumkasten; Fig. 3e shows a plan view of a module frame having permeate spaces in the form of inserted boxes on all four sides;

Fig. 4 shows a system arrangement consisting of three superimposed frame units with inserted Permeat- space boxes and

Fig. 5a / b represent exemplary possibilities for the system structure.

A possible embodiment of a capillary or hollow fiber module with open or plug-in outer box-shaped perimeter spaces according to the invention is illustrated with reference to FIG. 3e.

The invention is not limited to the above embodiments.

Rather, a variety of variants and modifications are conceivable that make use of the inventive concept and therefore also fall within the scope.

FIG. 1 shows the arrangement of individual capillaries 10 relative to one another. The individual capillaries 10 run parallel to one another within one layer, the capillaries 10 in FIG. 1 a in the north-south direction and the capillaries 10 in FIG. 1 b in the west - Oriented East. The next capillary layer 12 below or above may also have directional capillaries 10 or even those which are at an angle thereto. Preferably, the capillaries 10 are one layer 12, as shown in Fig. 1c, at 90 degrees to those of an adjacent layer 12. According to another embodiment, each layer may also consist of a capillary mat. This can consist of two layers of capillaries 10, which are woven at an angle to one another or from a layer of capillaries 10, to which individual threads extend transversely as a weft.

2a to 2d show a module frame 5 with an inside, from

Liquid flow through capillary layer stack. As shown in the schematic diagram in Fig. 2a, the capillaries are potted or glued in their end portion 14 with the module frame, the ends 15 remain open (Fig. 2b). The frame is flat above and below. For round frames, the exposed capillary ends 15 are visible on the entire circumference, with rectangular frames on at least one or on all sides. FIG. 2c shows a top view of a module frame which has a plurality of capillary layers 12, which are arranged at 90 ° to each other. The permeate discharge takes place at the open capillary ends 15 which are potted with the frame. Reference numeral 30 shows by way of example a permeate exit from capillaries of the layer X, while reference numeral 32 shows by way of example a permeate exit from capillaries of the layer X-1. Furthermore, injection capillaries 20 are still integrated between the individual capillary layers 12 in the module. Injection capillaries 20 are nonpermeable capillaries or tubes which are confined within the frame at one end only and open at the other end within the frame and capillary layers. The injection tubes 20 can be the same length or have different lengths. According to a further embodiment of the invention, the injection capillaries 20 are roughly open-pored, perforated or slotted and enclosed in the frame. The injection tubes 20 serve to introduce the fluid. In a membrane reactor, which consists of many modules arranged one above the other, different liquids can be introduced by means of these injection capillaries in the different intermediate layers. Furthermore, the injection tubes 20 ensure easy flushing of the modules with liquid and / or gas. Also, a liquid to be filtered can be introduced directly into the capillary stack.

Such module frames can now be further processed individually into frame modules or, according to FIG. 2d, can also be combined to form larger module frame units, so that units with a large membrane area can again be formed from them. Such frame modules can then be used in a variety of ways in a process engineering design.

An outer box 40a is now pushed onto individual module frames according to FIG. 3a and glued or welded to the module frame. This creates a space on the outside of a module frame. According to a further preferred embodiment, such a box 40b is inserted according to FIG. 3b into a groove previously cut or milled into the potting / gluing compound and then glued / welded. Such boxes may also be mounted on one or more sides of an entire module frame unit, as shown in FIG. 3d.

A special feature of these boxes 40a and 40b is that their outer surfaces (see Fig. 3a, 3b, 3d) at least partially may consist of a removable and closable cover 42 and this fluid-tight at its Kan- sealed. This cover 42 may be made of transparent material. The side view 3c shows that the open ends 15 of the capillaries 10 are visible through this removable, transparent cover 42. By way of example, FIG. 3c also shows two process connections 48 to the outer space 40a or 40b. During an integrity test, but also during operation, defective capillaries 10 can be visually recognized through the window. In the case of a detected defect, the permeate removal of the respective module unit 5 can be closed immediately. According to the invention, a motion detector can also be installed in each permeate space 40a / 40b which, during operation or during the integrity test, detects any fountains emerging from individual capillaries and reports such a defect. The repair of a capillary recognized as defective takes place through the opened cover opening 42, in which the ends of the corresponding capillaries are closed.

According to FIG. 3e, the embodiment can also be designed in such a way that individual layers of capillaries only end open open on one side of the module frame and thus also in different boxes. One or more capillary layers 12 may consist of so-called injection capillaries 20. These ends can be pressed in a separate external space 40a or 40b via the fluid directly into the permeate package. This is z. B. desirable for the introduction of gas around the capillaries 10 with gas bubbles clean or for the introduction of cleaning liquid directly to the capillaries 10 or even fluid to supply evenly and directly to the capillary.

A single frame module 5 or also to a module unit 6 stacked and interconnected frame modules can be provided with a lower and a top (it creates a head and a floor space) and so operated. A larger unit 8 results if, according to FIG. 4 a, a plurality of stacked modular units 6 with intermediate pieces 50 and a lower part 52 and an upper part 54 are provided. In both cases, this allows the flow through the capillary 10 interspersed with the inner channel of the unit 8 thus created, wherein flow rate and pressure can be set very different depending on the application.

Individual module units are fluid-tightly sealed with respect to intermediate 50, lower 52 and upper parts 54. This can be done by gluing. However, it is advantageous the sealing via seals or clip connections. A further and advantageous possibility according to the invention is the compression of the entire arrangement, so that all seals seal fluid-tight. The compression can be done manually via a spindle mounted over the top 54 or automatically via a hydraulic device. It is also possible that at the corners of the arrangement of the modules threaded rods are attached, which are connected via eyelets with the modular units 5, by means of which the entire assembly 8 can be screwed together.

The intermediate pieces 50 and the lower 52 and upper parts 54 may, if necessary, be provided with process and metrological connections.

A unit shown according to FIG. 4a can now be operated procedurally in a process plant according to FIG. 5a or 5b. The following modes of operation are possible individually or in combination with each other.

Filtration operation according to FIG. 5a: Fluid is supplied via the supply line and V1. The interior of the modules is filled. If necessary, depending on the application, pump P1 will circulate the fluid through valves V2 and V3. This is a cross-flow speed adjustable.

Filtration operation according to Fig. 5b: The supply line for the fluid is connected via a valve with the purge gas line. Fluid is supplied with the purge gas valve closed and then introduced directly into the capillary layer stack 12 via the injection capillaries 20.

Flow reversal: By reversing the direction of flow of pump P1, a reversal of the flow direction through the module assembly can be achieved.

Permeate Discharge: The driving force required for the separation process can be applied via the application of vacuum (pump P2), via the application of supply pressure, via the hydrostatic pressure of the liquid column (high headspace) or via a combination of these. The transmembrane pressure (TMP) of each individual module 5 (or individual module groups 6) can be regulated separately by means of corresponding valves.

Backwashing: Backwashing can be done by injecting permeate through pump P3 into the permeate tubing and thus into the inside of the capillary tube. 10. Each individual module 5 (but also individual module groups 6) can be controlled by appropriate valves.

Cleaning: The pump P4 is to be cleaned. Different modes of operation are possible: circulation through the entire module structure 8 from bottom to top or vice versa; Circulation over individual module groups 6 from bottom to top or vice versa; Circulation over each module 5 with fully filled module structure 8 from bottom to top or vice versa; Circulation over each module 5 with only up to about module 5 to be cleaned module assembly 8 from bottom to top or vice versa.

A module flush (fast flush) of the unit according to FIG. 5a or 5b is possible by increasing the circulation speed via pump P1 and by connecting the pump P4. With P4, each module can also be individually rinsed. This can be done during the ongoing filtration operation and also in both directions of flow. The cleaning effect of the capillaries can furthermore be achieved by introducing the entire supply of fluid to be separated only via the injection capillaries 20 of a single module unit 6. This creates within the capillary stack of this single module unit 6 a strong flow, which acts to a certain extent cleaning off. After a certain time, another module unit 6 can be switched, and so on. A similar effect can be achieved in that a strong overflow of the capillaries of a single module unit 6 is produced by P4 and switching of corresponding valves.

The purge gas supply into the unit 8 according to FIG. 5 a or 5 b is possible via the corresponding valves for all modules, for individual module groups 6 or for individual modules 5. This can be done during filtration operation, but also during the cleaning, during the module flushing and during the backwashing. It is advisable to combine the gas flush with liquid circulation, so that a mixture of liquid and gas bubbles is formed. This fluid circulation can be generated with the pump P4.

Blanking of the unit according to FIGS. 5 a and 5 b is possible by opening the uppermost gas valve and a drain valve.

The integrity test can be performed in both directions (out / in and in / out). By appropriate valve circuits module by module can be tested become. After blanking and closing all exhaust and intake valves, gas pressure can be applied permeator or retentate side and a pressure drop over time can be measured.

If the integrity test indicates that there is a capillary defect in one of the module units 6, the module space 8 is filled slowly above the level of the relevant unit 6. In addition, pressure can be applied when the interior is full. Through the module window 42 is from a certain liquid level or a certain

Pressure to see how fluid is amplified from one or more defective capillaries

10 leaves. In most cases, the increased fluid leakage will already be detected during ongoing controls during operation. The corresponding module 6 can be isolated upon detection of defects by appropriate valve circuit until the defective capillaries 10 can be repaired.

If the defective capillary 10 is identified, it will continue to leak liquid from the defective capillary 10. One opens the corresponding window 42 and can now plug the capillary end 15.

A fast flush is also easily and effectively possible. This can be done by increasing the flow rate of the circulation pump P1 or connecting another pump parallel to P1. By changing the conveying direction of both pumps, this is possible even in both directions. A long-lasting fast flush is furthermore possible because the liquid to be separated is introduced over a certain time only via the injection capillaries 20 of a single module 5. This creates within this module 5 a strong flow, which has a cleaning effect. After some time, another module 5 can be switched and so on. A similar effect can be achieved in which a strong overflow of a single module 5 is generated by P4 and switching of corresponding valves.

Claims

Godfathering

1. capillary membrane module of permeable capillaries and / or hollow fibers with inside and / or outside depositing layer, which are layered in layers of approximately parallel capillaries and have a certain distance from each other, the capillaries frame-shaped bordered on at least two sides , in particular potted or glued, wherein on at least one of the enclosed sides, the capillaries of all or individual layers on the outer peripheral surface to the outside open, characterized in that at least one of the sides of a single module (5) or a unit (6) from an individual or a plurality of stacked and fluid-tightly interconnected modules (5) an outside box-shaped compartment (40a, 40b) is fluid-tight up or inserted.

2. capillary membrane module according to claim 1, characterized in that the outer box (40a, 40b) on the frame side up or inserted into a groove in the outer frame side.

3. capillary membrane module according to one of the preceding claims, characterized in that the plugged or inserted Kompartiment- boxes (40a, 40b) to improve the flow, the cleaning and the

Reduction of the internal volume non-parallel surfaces and non-rectangular corners and edges have.

4. capillary membrane module according to one of the preceding claims, characterized in that at least one side of a Kompartimentkastens (40a, 40b) consists of a removable, reusable and fluid-tight sealable lid (42) and / or is made of transparent material.

5. Capillary membrane module according to one of the preceding claims, characterized in that the plugged-in or inserted compartment boxes (40a; 40b) contain process-technical connections (48) via which from outside or from other compartment boxes (40a, 40b) can be added and removed.

6. capillary membrane module according to one of the preceding claims, characterized in that the plugged or inserted compartment compartments (40a; 40b) contain metrological connections for detecting process and process engineering data and / or at least one motion sensor for finding defective capillaries.

7. capillary membrane module according to one of the preceding claims, characterized in that at least individual permeable capillaries (10) or at least an entire capillary layer (12) by non-permeable capillaries or tubes (20) are replaced, said injection capillaries (20) only on one end are bordered in the frame and the other end ends open within the frame or bordered at both ends in the frame and are carried out roughly porous, perforated or slotted.

8. capillary membrane module according to one of the preceding claims, characterized in that the permeable capillaries (10) and the non-permeable Injektionskapillaren (20) have different inner and / or outer diameter.

9. capillary membrane module according to one of the preceding claims, characterized in that the non-permeable capillaries or tubes (20) have different lengths and made of plastic, ceramic, metal or any other material.

10. capillary membrane module according to one of the preceding claims, characterized in that individual capillary layers (12) are replaced by a fabric, mesh, non-woven, mesh, screen or the like, which serves the flow distribution and / or the stabilization of the capillary.

11. capillary membrane module according to one of the preceding claims, characterized in that individual capillaries (10) of at least one layer (12) by wires, yarns, threads and / or the like are replaced, which serve to stabilization of the capillary.

12. capillary membrane module according to one of the preceding claims, characterized in that at least two of the capillary membrane modules (5) are connected to each other reversibly or non-reversibly fluid-tight manner to a module frame package or module unit (6), wherein the modules (5) arranged one above the other and / or side by side.

13. A capillary membrane module according to claim 12, characterized in that at least two module units (6) are combined to form a total module unit (8), wherein the individual module units (6) are interconnected via at least one intermediate piece (50).

14. Capillary membrane module according to one of claims 12 or 13, characterized in that on the uppermost module (5) of the module unit (6) or the total module unit (8) an upper part (54) and at the lowest module a lower part ( 52) is attached.

15. capillary membrane module according to claim 13, characterized in that the at least one intermediate piece (50) and / or the upper part (54) and / or the lower part (52) procedural connections for the supply and removal of liquids and / or metrological connections for process and procedural data acquisition can have.

16. capillary membrane module according to claim 14, characterized in that in the upper part (54) or above each module unit (6) a trickling system is attached, via which the capillaries can be acted upon with liquid.

17. capillary membrane module according to one of claims 13 to 16, characterized in that above and / or under at least one module unit (6) has a coarsely filtering layer is attached, which serves as a pre-filter and safety.

18. Capillary membrane module according to claim 13, characterized in that in each case at least two compartment boxes (40a, 40b) are connected to one another in such a way that at least two modules (5) or module units (6) are arranged one behind the other in series - Flow or dead-end operated and the permeate flow takes place from the inside out.

19. Capillary membrane module according to one of the preceding claims, characterized in that transversely and / or with the direction of the capillaries and between each of the frame-shaped sides of the module one or more intermediate walls made of plastic, sheet metal, perforated plate or other material are inserted These intermediate walls can also be cast in, so that the interior of a module frame is divided into two or more flow segments.

20. Capillary membrane module according to one of the preceding claims, characterized in that, in a module (5) with capillaries (10) running exclusively in one direction, two of the sides of the module consist of capillary potting compound and two walls of plastic connected thereto, Sheet metal or other material, where the walls can be wavy.

21. Production of a capillary membrane module according to claim 1, characterized in that the capillary layer stack (12) is impregnated for its temporary stabilization in at least one area with a solidifying mass which is later washed out again.

22. Production of a capillary membrane module according to claim 21, characterized in that the sides of the capillary stack are potted or glued in such a way that perforated or non-perforated adhesive tape and / or layers of adhesive are applied between individual capillary layers.

23. Production of a capillary assembly according to claim 21 or 22, characterized in that the membrane modules (5) or module units (6) with each other and with respect to the intermediate pieces (50), the lower part (52) and the upper part ( 54) are sealed in a fluid-tight manner by compressing the entire assembly (8) by a spindle or a hydraulic device or by screwing together the entire assembly (8) by threaded rods attached to the corners and / or sides of the assembly.

24. A method for operating a capillary assembly according to claim 12, characterized in that the filtration, backwashing, rinsing and cleaning tion with gas, liquid or a mixture of both at the same time or overlapping takes place.

25. The method according to claim 24, characterized in that the flow direction of the permeate can be adjusted so that it is either out-in (lumenseitiges suction or Retentatseitiges pressing) or in-out (Iommesiges pressing or Retentatseitiges suction).