DD139796A5 - FILTER ARRANGEMENT - Google Patents

Description

conductor arrangement

Field of application of the invention

A preferred field of application of the filter arrangement is the cleaning of waste water from the textile finishing of chemicals such as thickening and the like, which have considerable molecular sizes.

It is already a filter assembly with 'at least one tubular filter body with porous Y / andu ng, through which the liquid passes substantially radially', known, are retained at the entrance surface particles above a certain size.

Rohrförinige filter body of this type are made of porous plastic, ceramic, metal, graphite, etc. known. They serve either directly as a filter body or as a carrier for a filter membrane, which has been formed from a liquid phase at the inlet surface of the filter body and allows a particularly fine filtration. With membrane filtration, mixtures of solvents and dissolved particles can be separated. The separated particles are retained at the surface of the membrane.

If the solvent and dissolved component of the solution to be filtered have approximately the same molecular dimensions as e.g. at

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Saline and water is the case, the separation process is referred to as reverse osmosis. Since the separation process is contrary to the osmotic pressure, the pressure on the solution side must exceed the osmotic pressure, if it is to come to a filtration. The required pressures can be significant; a 10% saline solution has e.g. an osmotic pressure of 80 atm, which must be overcome. '

If the molecular dimensions are significantly different from each other, ultrafiltration is used. Ultrafiltration is used for concentration, fractionation or purification of macromolecular solutions. Because of the high molecular weight of the dissolved component compared to the solvent, generally> 2000, the solutions have only a low osmotic pressure, therefore the separation in these cases can be carried out at relatively low pressures, for example 1 to 10 atm.

The particles to be separated are retained at the surface of the membrane. Unless they are removed by appropriate means, i.e. when e.g. the liquid to be filtered is substantially stationary against the entrance surface, a layer of the separated particles is formed over the course of the operation, which reduces the permeability of the filter arrangement and increases the pressure to be applied. Such a filter arrangement must therefore be freed from the layer formed at regular intervals. '

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Objective "of the invention

The aim of the invention is to provide a filter arrangement of the type mentioned in such a way that a continuous operation at constant pressures is possible and thus an increase in productivity can be achieved.

The invention has for its object to provide a filter assembly with at least one tubular filter body with a porous wall, through which the liquid passes substantially radially, wherein at the 3intrittsoberfläche particles above a certain size aurückückückon v / earth to create, in which the Strömungsvveg is designed in that the liquid to be filtered is constantly in motion.

This object is achieved in that in the Sintrittsoberfläche of the tubular filter body at least one after, closed on the outside, one of an inlet to an outlet leading Zwangsströmungsweg forming hat is provided.

Through the hat or the grooves, two things are achieved:

First of all, there is a flow path along the surface through which the total amount of liquid to be filtered must pass with relatively narrow flow cross sections. The liquid to be filtered experiences good contact with the entrance surface through the walls of the grooves. The liquid to be filtered is everywhere in motion relative to the entrance surface, so that there retained particles, the

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were separated from the filtrate by the material of the filter body, are immediately washed away with it and remain in suspension in suspension or in solution. This effect can be promoted by designing the grooves so that the flow becomes as turbulent as possible to prevent the formation of laminar boundary layers with virtually stationary near-wall zones at the entrance surface. Thus, it can not be the case that parts of the entrance surface form so-called dead zones in which deposited particles accumulate in the absence of transport to a layer, nor do substantial portions of the liquid come into contact with the entrance surface by remaining inside a larger cross-section fluid flow ,

The other effect of the grooves consists in the enlargement of the inlet surface of a filter body, which otherwise has the same outer dimensions, with respect to a purely cylindrical inlet surface. This is particularly important in the event that the actual filter body at the inlet surface carries a filter membrane. As a result, the throughput is increased at a constant input pressure. As a surface enlargement is such by a factor of 2 to 3 into consideration, but without being limited thereto.

In principle, the entrance surface may be both the inner surface and the outer surface of the tubular filter body. However, the preferred embodiment is that in which the outside is formed as an entrance surface provided with grooves. This initially for practical reasons with regard to the simplified attachment of ITuten and also because on the outside of

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c ~

in the beginning a larger surface is available. A more important reason for this preference, however, is that the sintering materials or other porous materials which come into consideration as material for the filter bodies are able to absorb substantially higher compressive stresses than tensile stresses. At the same pressure, therefore, a filter body, if the pressure is applied from the outside, be made thin-walled. This reduces the flow resistance, and thus the power required per unit volume of the filtrate.

The hats are conveniently closed by a close to the inlet surface of the tubular filter ¬ body, cylindrical, outer surface.

The grooves can run axially or helically or also meander-shaped on the tubular filter body. The "closed surface" may be provided by the circumference of a tube which-in the case of grooves mounted on the outside of the tubular filter bodies-surrounds the tubular filter body under installation. It is.also formed in this case by an outer, separate from the filter body part.

Since the liquid to be filtered under certain circumstances must be placed under a considerable pressure in order to press the filtrate through the pores of the membrane or the filter body, it is recommended that the tube is arranged with the filter body in a pressure housing in which the free Circumferential surface of the tube of the concentrate pressure acts.

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In this way, the pipe can be partially depressurized, if it is ensured that the concentrate is under pressure. The pipe construction can be kept easier, because then it only has to withstand the differential pressure from the inlet pressure and the back pressure of the concentrate. This differential pressure can be selected by appropriate adjustment of the backpressure. It must only be at least as large as is necessary to pass the liquid to be filtered through the grooves of the filter body. While the input pressure to be borne by the pressure housing may be of the order of 100 bar in a practical embodiment, only values of a few bar remain for the differential pressure to be sustained by the pipe. The enclosure of the filter body with a pipe thus has the purpose to cover the high-pressure Muten with an element which on the other side allows access for a pressurized liquid (concentrate) and is thus partially relieved of the high pressure.

A practical embodiment of the invention can be realized in that the inlet is located at one end and the outlet at the other end of the tube, that in the pressure housing, a pressure-tight, seen in the vicinity of the inlet end, against the housing and the tube sealed partition is provided which seals off the housing into a first and a second chamber, and that the inlet of the filter body and the inlet opens into the pressure housing in the first chamber and the concentrate outlet of the pressure housing in the second chamber.

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The liquid to be filtered can not immediately pass over from the inlet of the pressure housing to its outlet, but is forced to cover the path along the filter bodies from their inlet to their outlet.

The concentrate outlet of the pressure housing, a pressure control valve can be connected downstream to produce the aforementioned back pressure, which relieves the pipes partially depressurized and should also affect the filtration process.

The "closed surface" that results in the forced flow path can, as described above, be provided by the circumference of a tube surrounding the tubular filter body under installation. Separate parts are required for the formation of the forced flow paths from the filter body. In addition, the gussets remaining between the tubes form considerable loss cross sections.

In order to reduce the effort for the formation of the "closed surface" of the grooves and to avoid loss cross sections, the hat may be closed by the surface of an adjacent tubular filter body according to an important embodiment of the invention.

The adjacent filter body thus abut against each other and limit even the forced flow paths, so that no additional and loss cross sections conditional limiting elements are required.

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Most advantageously, this invention is realized in such a way that the filter body complement each other in their cross-sections to a dense-packed overall cross-section except for the left through the hats Plüssigkeitskanäle.

The filter body should thus provide a compact package in the cross section, only the inner cross sections of Filterkö.rper and the other surface through the hats left channels are free.

This can be realized in such a way that the filter bodies have a uniformly polygonal cross section suitable for forming a tight packing.

By this is meant that the cross-sections should be packed together without leaving intermediate spaces to a larger cross-section. B. cross-sections in the form of an equilateral triangle, a square, an equilateral hexagon. In contrast, a pentagonal cross-section is considered.

The hexagonal cross-sectional embodiment is generally preferred because it is still quite close to a circular cross-section and the paths which the liquid must travel through the material of the filter body to reach the inner wall are of similar length at entry from all points of the outer periphery ,

In points 5 to 9 of the claim invention advantageous arrangements and designs of the hats are reproduced.

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Points 10 and 11 describe the practical realization of housing the entirety of the tubular filter bodies in a housing,

Making a v / eiteren feature, the filter assembly is characterized in that the hats of adjacent filter body with the open sides are opposite to each other.

Advantageously, in each case a plurality of grooves on one side of a polygon are adjacent. The hats have a curved in the depth of Polygonseiten cross-section. The hats may also have a flat-rectangular cross-section with the longer side parallel to the side of the polygon. «

Furthermore, the men can have a triangular cross-section with a tip in the center of the filter body »'

Conveniently, the entirety of the tubular filter body is arranged in a tubular housing, and the non-fillable by the filter body residual cross-sections are filled by shaped pieces corresponding cross-section.

Finally, one feature of the filter assembly is that since the totality of the tubular filter bodies is arranged in a housing with two end pieces, and the tubular filter bodies are closed at one end, a sealed connection at the other end

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the passage opening of the tubular filter body to the outside of the local end piece producing intermediate pieces are provided.

Ausführungsbeisp iel

The invention will be explained in more detail below with reference to several embodiments. ¹ In the accompanying drawing show:

Pig. ' 1: a longitudinal section through a so-called module with several filter bodies;

Fig. 2; a cross section along the line H-II in Figure through a single filter body;

Fig. 3ί a Fig «1 corresponding longitudinal section of another embodiment along the line IH-III in Fig. 4J

4ϊ is a cross section along the line IV-IV in Fig. 3 »

5 shows a view of a further filter arrangement according to the invention;

6 shows a cross section through the FiIteranordnung of Figure 1 on an enlarged scale ..;

7 shows a cross section through a single tubular filter body with different hat cross-sections in turn to an enlarged scale;

8 shows a cross section through a compensation profile;

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FIG. 9 shows a further embodiment with an approximately square cross-section of the tubular filter body;

Fig. 10: the connection of the filter body on the outlet side.

The filter assembly 10 of Fig. 1 comprises a pressure housing T, which consists of a tubular part 2 with pressure-tight at the ends mounted lids 3 »4. The tubular part 2 has an inner shoulder 5 against which in the axial direction ei-ne the cross-section of the tubular housing part 2-filling intermediate wall 6 rests on a ring seal 7. The intermediate wall 6 has cutouts in which pipes 8, which are parallel to the pipe axis, are arranged tightly, of which two are shown in FIG. The arrangement of the tubes 8 in the cross section of the pressure housing 1 is made so that as many tubes 8 can be accommodated.

In the tubes 8 filter body 9 are arranged, which rest with its outer circumference on the inner circumference 26 of the tubes 8 * The entrance peripheral surface is its outer peripheral surface. The filter body 9 are themselves tubular and closed at its lid 3 end facing by plugs 11. On its outer periphery, the filter bodies 9 have a helical hat 12, which forms a helical fluid channel between the filter body 9 and the inner circumference of the tube 8, into which the liquid enter at the inlet 13 located in FIG. 1 and from which it flows at the outlet 14 can exit at the right in Fig, 1 right end again. The walls of the groove 12 form the inlet surface ': 25. At this end, the filter body 9 projects beyond the end of the

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Tube 8 and is sealed in a corresponding recess 15 of the right lid 4 via a ring seal 16 which is printed by a pressure ring 17 in the recess 15.

The intermediate wall 6 divides the interior of the pressure housing 1 in a pig. 1 left first chamber 18 into which the inlet 19 of the pressure housing 1 opens. The right in Fig. 1 located chamber 20 communicates with the concentrate outlet 21 of the Druckgehä.uses 1 in connection. The interior 23 of the tubular filter body 9 is connected via outlets 22 in the lid 4 with the outside in combination.

In the chamber 20, there is virtually the same pressure as in the chamber 18 and in the hat 12, since this pressure acts both on the inner circumference 26 of the tubes 8 and on the free outer peripheral surface 28, the tubes 8 are substantially depressurized and can be sized accordingly easily *

The conductor arrangement ^ 10 operates as follows: The liquid to be filtered enters the chamber 18 through the inlet 19 of the pressure housing 1. From this, the liquid to be filtered passes through the inlet 13 in the helical groove 12, moves helically in this hat along the filter body 9 and enters the outlet 14 from the hat 12 into the chamber 20, from where it as a concentrate from the outlet 21 of the pressure housing 1 emerges. By the pressure control valve 24 of the in the chambers 18; 20 ruling pressure to be controlled.

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During dwelling in the helical groove 12, a portion of the liquid to be filtered enters the interior of the filter body 9, leaving behind suspended and / or dissolved particles at the entrance surface 25 formed by the outer periphery of the filter body 9 do not settle, but are continued by the flowing liquid immediately, ie remain in the moving concentrate.- After passing through the wall of the filter body 9, the filtrate enters the interior 23 of the filter body and can be withdrawn at the outlets 22. The concentrate is returned to the inlet and kept in circulation, optionally after removal of entrained substances and combination with new liquid to be filtered. In this way, a continuous separation of the filtrate, e.g. of no water from sewage.

The embodiment of FIGS. 3 and 4 differs from that of FIG. 1 and 2 only in terms of the formation of the filter body 9, which have distributed on the outside over the circumference axial üüuten 32 of approximately triangular in the embodiment of cross-section. Instead of the. Axial grooves 32 may also be provided with a slight pitch having ITu th, which can improve the contact of the liquid to be filtered with the inlet surface 25 'of the filter body 9 ^1. Otherwise, the structure and operation of the embodiment according to FIGS. 3 and 4 those of FIGS. 1 and 2.

The triangular cross-sectional shape of the grooves in the Ausführungsbeisüielen of Fig. 1-4 is not mandatory.

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Ea can also be rounded or more rectangular groove cross sections into consideration.

The filter assembly 110 of Pig. 5 includes a pressure housing 101, which consists of a tube 102, for example, 220 mm inner diameter and about 8 mm wall thickness of corrosion-resistant steel. The tube 102 is pressure sealed by end pieces 103 »104 in the form of lids. The filtering liquid is supplied at the port 105 under high pressure, for example 70 bar, and exits at the port 106 again. The filtrate passes through the intermediate pieces 107 in the chamber 108 and is withdrawn through the terminal 109 '.

According to Pig. 6, the interior of the tube 102 is substantially filled by a packet of individual filter bodies 109 having an outer cross section in the form of a regular, i.e. has equilateral and equiangular hexagon. The filter bodies 109 are made, for example, of porous graphite or porous sintered tubes made of corrosion-resistant steel. The entirety of the filter body 109 complements a closely packed cross-section in turn in the form of a regular hexagon, which is surrounded by the inner circumference of the tube 102. In the embodiment, ninety-two filter bodies 109 are combined.

The tubular filter bodies 109 have an inner through-hole 111 and on the outside in the longitudinal direction continuous hats 112, which are arranged so that they correspond to the corresponding hats 112 on the opposite

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overlying hexagon side of an adjacent tubular filter body 109 just opposite. In this way, continuous liquid channels are formed in the longitudinal direction, which form a forced flow path for the liquid introduced under pressure at the connection 105.

So that now the liquid actually passes the channels 113 and does not take the path of lesser resistance through the outer remaining outside the package of the tubular filter body 109 remaining Querschhitte, these remaining cross sections are filled by shaped pieces 114 corresponding cross section, one of which is shown separately in Fig. 8 is. The fittings 114 must be able to withstand the pressure of the liquid so that they do not open by giving way to the liquid. They may extend over the entire length of the filter assembly 110. "Under certain circumstances, it may also be sufficient if they are transverse Schottschartig provided only at individual locations.

In Fig. 7 various possibilities of the cross-sectional configuration of the grooves are shown on the surface of the filter body. It goes without saying that, in practice, the same IJut cross section is present on all six sides of the filter body 109.

The ITutters 112, which are also present in FIG. 6, have an equilateral triangular cross section and point inwards with the tip, i. against the passage opening 111 of the filter body 109. They are arranged in the embodiment of four on a hexagon side.

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When choosing the hat cross section, a compromise between different requirements must be found. Of course, the largest possible inlet surface of the filter body 109 is desirable. However, the cross section of the channels 113 formed by the grooves must remain so large that an adequate flow rate still results and the settling of filter residues and lint on the groove walls is avoided , The triangular cross-sectional shape of the ITutils 112 seems to be a useful compromise, especially because the entrance surface is not too far away from the inner through-hole 111, and thus reasonably uniform liquid entry is expected. Also, the ITutils 112 are reasonably easy to manufacture because of their shallow depth. ¹

The ITutils 115 are not so favorable because the achievable entrance surface and the resulting channel cross-section are small. In the hat 116, the channel cross-section is indeed cheaper, but still given a small entrance surface. ,

The lenticular cross-section of the groove: 117 corresponds in its usefulness as the groove 115 »In the ITuten 118; 119 Although relatively large inlet surfaces are present, but the channel cross sections are already too large, so that the flowing in the middle of the channel liquid fractions have little opportunity to come into contact with the channel wall. In particular, however, the distances from the individual points of the entry surface to the wall of the passage opening 111 are very different.

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9, the tubular filter bodies 129 have approximately square outer cross section and have on each square side three hats 120 of triangular cross section with inwardly pointing tip. The remaining on the outer circumference of the package of the filter body 1.29 to the inner circumference of the tube 102 remaining cross sections are filled by fittings 124 »125 corresponding cross-section.

The entire interior of the tube 102 to the left of the transverse bulkhead-like plate 130 (FIG. 5) is under the pressure of the liquid to be filtered introduced through the connection 105. The individual filter bodies 109 are thereby pressure-relieved on all sides and are not affected by the pressure prevailing in the channels 113 Pressure apart. The liquid flowing in at connection 105 thus flows through channels 113 to its right-hand end as shown in FIG. 5, which coincides with the end of filter element 109, as can be seen from FIG. This end of the filter body 109 leaves a distance to the Querschottartigen plate 130 which is bridged by the tubular intermediate pieces I3I The spacers engage with a projection 132 in the through hole of the filter body 109 and with a projection 133 at the other end through the plate 130 therethrough. Auf'diese way, the through holes 111 are sealed to the Fig. 5 and 10 located to the right of the plate I30 space 103, from which the filtrate is withdrawn virtually without pressure or low pressure through the terminal 109.

From the ends of the channels 113 in the between the individual intermediate pieces 131 between the ends of the filter

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body 109 and the plate 130 left intermediate space entering to be filtered liquid is discharged through the terminal 106 and circulated again.

The gap 134 facing side of the plate 130 is plated with a sheet 135 of corrosion-resistant steel.

The exact design of the filter material does not play a decisive role. It may be a porous filter body which deposits particles contained in the liquid to be filtered with the aid of its pores, but also such a filter body in which a coherent layer has been deposited on a supporting porous body at the entrance surface is a filter membrane and represents the actual • filter layer. Such membranes can be used to separate particles down to molecules dissolved in the liquid to be filtered.

An important application of the filter assembly is the purification of effluents from the textile finishing of chemicals such as thickening and the like, which have significant molecular sizes. The filter bodies consist of graphite or sintered tubes made of corrosion-resistant steel. They have a diameter of 15 to 25 mm and are, for example, according to the order of magnitude of about 30 to 100 (the drawing of FIGS. 1 and 3 is only schematic at this point and does not reflect the actual conditions) in a common pressure housing to form a so-called module ,

Claims (9)

-19- 6.4.1979 AP B 01 D / 209 927 54 736/26 invention claim The filter assembly comprises at least one porous wall tubular filter body through which the fluid passes substantially radially, retaining at the entrance surface particles of a certain size, characterized in that * Cv the inlet surface of the tubular filter body (9; 9 ^f ) is provided with at least one hat (12; 32) closed to the outside and forming a forced flow path leading from an inlet (13) to an outlet (14). 2, .Filteranordnung according to item 1, characterized in that the TTuten (12; 32) closed by a at the inlet surface (25; 25 ') of the tubular filter body (9> 9') tight fitting, cylindrical, closed outer surface are, 3, filter arrangement according to point 2, characterized in that 'the hats (32) extend substantially axially to the tubular filter body (9 ¹ ). 4, filter arrangement according to point 2, characterized in that the hats (12) run helically on the tubular filter body (9) « 20 9 927 -20- 6.4.1979 AP B 01 D / 209 927, - ,, ··. 54 736/26 5 · Filter arrangement according to item 2, characterized in that the grooves run meander-shaped on the tubular filter body. 6. Pilter arrangement according to one of the items 1 to 5j, characterized in that the hats (12; 32) are provided on the outer circumference of the tubular filter body (9; 9 ¹ ). 7. Filter arrangement according to one of the items 2 to 6, characterized in that the closed surface is given by the inner circumference (26) of a tube (3). 8. Filter arrangement according to point 7 », characterized in that the tube (8) with the filter body (9; 9 ^f ) is arranged in a pressure housing (1), in which the free circumferential surface (28) of the tube (8) Concentrate pressure acts. , 9. Filter assembly according to item 8, characterized in that the inlet (13) at one end and the outlet (H) at the other end of the tube (8) are located in that in the pressure housing (1) located in the feast of the inlet end pressure-tight, against the pressure housing (1) and the tube (8) sealed intermediate wall (6) is provided which seals the pressure housing (1) in a first and a second chamber (18) or (20), and in that the inlet ( 13) of the filter body (9 5 9 ^f ) and the inlet (19) in the pressure housing (1) in the first chamber (18) and the outlet (14) and the concentrate outlet (21) of the pressure housing (1) in the second chamber (20). -21- 6 April 1979 AP B 01 D / 209 927 54 736/26 10, filter arrangement according to point 9, characterized'dadurch in that the concentrate outlet (21), a pressure control valve (24) is connected downstream. 11. A filter assembly according to any one of items 1 to 6, characterized in that the groove (112; 115; 116; 117; 118; 119) is closed by the surface of an adjacent tubular filter body (109; 129). 12. Filter arrangement according to item 11, characterized in that the filter bodies (109 5 129) extend in their cross-sections to a liquid channel © (113) left open by the grooves (112; 115; 116: 117; 118; 119). Complement tightly packed overall cross section. 13. Filter arrangement according to item 12, characterized in that the filter bodies (109; 129) have a uniformly polygonal cross section suitable for forming a tight packing. 14 · Filter arrangement according to item 13, characterized in that the filter body (109) have an equilateral and equiangularly hexagonal cross-section. Filter assembly according to any one of items 11 to 11, characterized in that the grooves (112; 115; 116; 117; 113; 119) of adjacent filter bodies (109; 129) extend with the open sides opposite one another. 16. Filter arrangement according to one of the points 11 to 15, characterized in that in each case a plurality of grooves (112) 20 9 927 -22- 6 April 1979 AP B 01 D / 209 54 736/26 are juxtaposed on a polygon side. 17. A filter arrangement according to any one of items 11 to 16, characterized in that the grooves (117, 118) have a cross-section which is curved in the depth of the sides of the polygon. 18, filter assembly according to any one of items 11 to 16, characterized in that the grooves (115; 116) have a flat-rectangular cross-section, whose longer side is parallel to the side of the polygon. 19. A filter arrangement according to any one of items 11 to 16, characterized in that the grooves (112, 119) have a triangular cross section with a tip having in the center of the filter body (109, 129). 20. Filter arrangement according to one of the points 11 to 19 »characterized in that · the entirety of the tubular filter body (109, 129) in a tubular. shaped housing (101) is arranged and the non-fillable by the filter body (109; 129) remaining cross-sections through shaped pieces (114; 124; 125) corresponding cross-section are filled. 21. A filter assembly according to any one of items 11 to 20, characterized in that the entirety of the tubular filter body (109; 129) in a housing (101) with two end pieces (103; 104) is arranged and the tubular filter body (109; 129) closed at one end and at the other end a tight connection of the passageway -23- 4/4/79 AP B 01 D / 209 92? 54 736/26 Opening (111) of the tubular filter body (109, 129) to the outside of the local end piece (104) producing intermediate pieces (131) are provided « For this 3 pages drawing