DE2257268A1 - METHOD OF REMOVING FOREIGN MATERIALS FROM GASES - Google Patents

Description

Jon Thordarson
Skipholt 51, Reykjavik, Iceland

concerning
Method for removing foreign matter from gases

The. Invention relates to the removal of foreign matter, namely solid or liquid particles or other gaseous ones Components from air or other gases, e.g. those that occur as industrial exhaust gases, e.g. in the context of electrolytic Aluminum extraction, the cement industry, the chemical industry, the mechanical industry, from large Oil-fired heating systems, e.g. those for the production of Fish oil or fish meal.

So far rotating filter devices have been applied in _r where scrubber at different speeds in a channel are arranged ,, also served devices with spokes or rods radially hang between the cylinder and the hub, which is fixed to an axis of rotation, and the gas to be purified axially through the filter device is guided (DAS 1 144 999, OS 1 815 279).

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Man. several such rotating filter devices can be used axially arrange one behind the other and also so that they run in opposite directions.

Such scrubbers were used to remove solid and / or liquid foreign matter from air or other gases applied by adsorption. In addition, they also serve to remove gaseous components from gases by absorption, whereby the adsorption and absorption (sorption) takes place in each case in a liquid film, the is formed by a corresponding liquid, e.g. B. water, and in the form of a thin layer arranged radially over Filter elements flow down or trickle. The filter elements can be slat-shaped, rod-shaped or the like that can be arranged together in the manner of a brush around a shaft.

This type of filter is important as it is. also for the removal of such particles are suitable under conditions where the humidity is so high that there is fog formation.

If necessary or expedient, a liquid is injected into the gas flow above the rotary filter. It but it is also possible that the filter itself is provided with liquid, which is then preferably in the middle Part of the filter, e.g. inserted via a hollow shaft.

The invention now brings a device for removing foreign matter particles from air or other gases that has a tubular gas passage, which is optionally provided with a fan for the forced gas flow. Furthermore, there is at least one rotating filter unit with a corresponding drive. The gas routing has where

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the filter is, similar to this, a round cross-section. Each filter is made up of at least one Centrally arranged shaft and at least one circumferentially arranged wheel rim together with a network of elongated Rods extending radially over all or the major part of the annular space between the central arranged shaft and the peripheral ring extend. The rod network is constructed in such a way that a liquid during operation under the influence of centrifugal force and surface tension adheres to the rods and flows outwards as a liquid film. With the liquid it can be washing liquid introduced through or in the immediate vicinity of the shaft with the aid of at least one atomizer act and / or one - one that was introduced into the gas line of the filter unit .. The liquid film serves to absorb the foreign matter. To collect "the entire flowing medium, which is the peripheral ring the filter device leaves, is at least 'a comprehensive Collection chamber provided.

The advantage of the device according to the invention lies in ■ that the peripheral ring has an e-· such a diameter that corresponds approximately to the diameter of the conduit for the flowing Medi'en _(o Fig 1). The walls of this line are interrupted to adapt to the ring with only a small tolerance, so that the liquid mixture on the circumference of the ring can be drawn off into a collecting chamber arranged around it, from there it can be used for further treatment and / or regeneration and, if necessary, after Reliquefaction for. Return line are provided.

To facilitate the exit of the liquid mixture into the collecting container, the ring can be interrupted.

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The rotation of the filter unit causes the air to move in a circular motion. This is very disruptive to the cleaning effect more than the rods of the filter unit cut through it perpendicular to the direction of flow of the air. This can be avoided, for example, by adding a number of Filter units are arranged axially in series and the filter units run in opposite directions of rotation. An embodiment of the device according to the invention, wherein a number of filter units are arranged axially in series and rotatable in opposite directions, can in in its simplest form consist of two units, each of which has its own drive mechanism, its own shaft and have rods as well as ring.

In a preferred embodiment, the device according to the invention comprises a number of rows of rods arranged on a central axis, which extend radially outwards almost to the surrounding ring, and indeed these change Rows of bars starting with the outside and extending radially inwards to almost the shaft. The two main ones Parts of the filter unit are therefore the first main part, containing a central shaft and assigned radially outwards Reaching rods ^ and the second main part containing a circular ring with associated rods extending radially inward. Both main parts have their own drive mechanisms for movement in opposite directions. To prevent a swirl flow of air can result in the Blades or blades are located in the gas pipe, preferably un-

from

indirectly in the direction of flow and / or behind the filter unit, at least to a certain extent in this Area to prevent a swirl flow.

When the filter unit entrains the air in a rotating motion, the air is under the influence of centrifugal force tend to lean on the girth and that is

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the more the rotation speed increases. The filter purity would force the air radially outwards, similar to a fan or blower. If this does not prevent it there is a great possibility or probability that the mixture of the liquid and the ! Foreign matter can flow back into the gas duct.

If the air should be blown out of the rotating filter unit without any obstruction, it will happen to noticeable overpressure and strong turbulence in the annular chamber around the gas line in which the liquid mixture is present is collected. The consequence of this is that the liquid. can flow back into the JRing and thus into the gas pipe. In the special construction of the device according to the invention, where there is a simultaneous rotation of the gas flow and / or is prevented behind the filter unit with this, this is avoided. It serves little purposei multiple and / or thicker filter units without radial blades or vanes in the gas line. Beyond that or in parallel for this purpose, two or more filter units, as mentioned, axially in series, they are designed so that their directions of rotation are opposite.

Even where vanes or vanes are provided, it is difficult to completely prevent the filter unit from opening a certain part of the gas pushes into the collecting chamber, but this phenomenon is largely avoided by the arrangement of the rings around the periphery of the bars. Of the The ring should sit as tightly as possible - with only a small amount of play - in the slot that breaks the wall of the gas line forms »It should work together with the wings or guide vanes,

Sq becomes an oppositely directed flow of the liquid mixture, the flows through the ring and into the gas line

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long, made more difficult by these measures. on the other hand should be prevented from entering the surrounding collection chamber escaping gas enters the atmosphere, the collection chamber can be designed gas-tight against the environment, e.g. using a gas-liquid seal.

The above-mentioned ring that closes off the periphery, the spoke-like Filter elements can be in a wide variety of forms, but in general it should be slightly wider than the axial width of the rod network itself. In this way, the ring catches the amount of liquid, which runs off the bars. The ring can advantageously have a channel-shaped cross section in the axial direction. The web part - seen from the outside - can be convex or concave. The outermost part can be punched in order to to allow easier escape into the collection chamber for the liquid mixture.

In a particularly preferred embodiment, the ring has a channel-shaped or Z-shaped cross section in the axial direction. The web part in the axial direction is inclined to the outside to facilitate the escape of the liquid * In the case of a channel-shaped cross-section, the peripheral part is perforated in the skin thing for the same purpose. The specific direction of flow of the gas stream is on the effectiveness of the filter unit of minor influence, since the centrifugal force substantially exceeding the force of gravity.

The rods mentioned above can be made of various materials, such as plastic, especially nylon or polyvinylchloride ^ and / or metals such as stainless steel.

The rods extend through the whole or a substantial part Proportion of the annular space between the ring and the hollow axis, via which the optimal central introduction of the liquid can take place in the gas flow. They hang between or

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are fixed to the axle and / or the ring, depending on the applied embodiment.

Such a hollow axis can be provided with channels for the separate introduction of liquid to each rod extending from it extends, provided it. By dividing the hydration into zones, you can use more than one type of fluid, depending on the desired working conditions. Even

So-called dry zones can be provided, i.e. without the addition of liquid, in order to remove the liquid from the gas flow to remove.

In another and simpler embodiment, the Hollow axle can be provided with atomizers for the liquid. In this case, the axis itself can be made of a material like a wire mesh, or openings and bores be provided for the exit of the atomized liquid into the rods and between them. Perforated pipes can be used also apply.

If liquid is to be introduced in front of the filter unit, spray nozzles can be seen in the gas line in front of the filter unit before. ■

It should be pointed out that this filter unit can advantageously be used to remove liquid particles (mist) from air or other gases. In this case, no other liquid is required. «The rotating filter unit removes the liquid particles with high efficiency, SB. 95 to 100 % removed

If the aim is to remove suspended solids or gases, e.g. from exhaust gases. Hydrogen fluoride, so one must use a washing liquid such as water or oil.

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As mentioned, the washing liquid can be fed through the axle. In some cases, however, it is often It is better to atomize the liquid in front of the filter unit in an air stream.

The rotating filter unit according to the invention is largely self-cleaning, which is particularly important when there are large amounts of suspended matter is a significant benefit. Other filter units easily become ineffective and need to be cleaned be taken out of service.

The filter units according to the invention are also distinguished by a minimal pressure drop. It is therefore possible to work with higher air velocities than with conventional filters, as a result, these rotary filter units are dimensioned smaller and thus also have a smaller space requirement.

With simple experiments, using the example of adding Kieseiguhr dust to an air stream using water as the ash liquid, the most favorable relationship between the rotational speed of the filter unit and the air speed can be determined, whereby cleaning effects of over 90 % can easily be achieved ^ as from the Diagram of Fig. 2 can be seen. The rotation speed of the rotary filter can be between 850 and 1220 rpm. The air volume can range from 46 to 94.7 micrometers of air. The dust content can be between 20 and 250 mg / m «

The invention is explained further with reference to the figures.

Fig. 1 with the sub-figures 1a-1d shows a device according to the invention, the gas line 2 of which is circular Has cross-section, at least where the rotary filter

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8 is fixed. They are also located in the gas pipe ■ 2 Blowers or fans 4 with their drive mechanism (e.g., electric motor) / and the drive mechanism 10 for the Rotary filter 8, The drive of the rotary filter can be with the help of an electric motor or with a transmission belt or be done hydraulically, pneumatically or mechanically. The rotation speed can be regulated, if yourself one or more. Parameters that affect performance * - flow, can change or if the service itself changed, should be

In the embodiments shown in FIGS liquid is introduced via the atomizer 3 above the filter unit. The direction of movement of the airflow is indicated by arrows. However, as already pointed out, the direction of movement of the air flow is of little importance on the effectiveness of the filter unit, because centrifugal force exceeds gravity.

The filter unit shown in Fig. 1 consists of an axis 12, rotatably arranged, for example according to the shape shown centrally in the center of the radial vanes 18. From the axis 12 often several rows or groups of a large number of rods 7 or 7 extend in the radial direction the like, which depend on the axis 12, 14 against the likewise rotatable _ring: the ring 14 fits over a small distance 19 in the wall slot in the gas pipe 2. in the embodiment shown here, it has Z-shaped cross section. .The web part forms the envelope of a truncated cone and is provided with flange parts. The slots 19 in the wall of the gas line 2 lead into the annular collecting chamber 16, "which is expediently equipped with a discharge for liquid and gas and is closed off by a liquid seal."

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1a to 1d show other embodiments of the ring 14, both channel-shaped and Z-shaped. In these sub-figures are the rods 7 and the perforations 20 to facilitate the passage of the liquid mixture indicated in the collecting chamber 16. The embodiment of the ring 14 in FIG. 1 corresponds to FIG. 1d.

According to FIG. 1, the line 1 is used to supply liquid to the spray nozzles 22 within the hollow axis 12. An advantage This embodiment is based on the fact that there are no moving parts. In Fig. 1 is due to the clarity the atomizer 3 is indicated, specifically in the gas flow in front of the blades 18 and the filter unit 8. The nozzles 22 and the atomizer 3 can be used separately or together as desired. However, the atomizer 3 will only applied in front of the filter unit (see the arrows indicating the flow directions in the two embodiments specify the device according to the invention).

The materials for the various parts of the device are selected according to the ambient conditions and the to cleaning gases as well as the polluting suspended solids and gas components and ultimately also with regard to the as Liquid phase applied to washing liquid, which is intended to form a liquid film in the filter unit. as Suitable materials are corrosion-resistant steel, polyvinyl chloride and nylon or other resistant materials as shown by polytetrafluoroethylene. In most cases, water will be used as the liquid component, optionally mixed with a surface-active, emulsifying agent or dispersing agents or with substances that are able to influence the pH value. For the adsorption of rather hydrophobic suspended solids, such as soot, hydrocarbons or chlorinated hydrocarbons with a high boiling point are more advantageous Applied wisely.

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The bars can have a wide variety of cross-sections. So they can because of their rigidity and effectiveness expediently have a V- or U-shaped cross-section. A strip shape can also be used; if necessary, the strips can be twisted. In this case, they must the strips are fixed between the inner and outer position will.

In the embodiment shown in Fig. 1, a single filter unit 8 is provided in which a number of rows of rods axially spaced over the. Axis extend.

As already pointed out, there is a slightly different one Filter unit consisting of two filter elements axially in series and designed so that they run in opposite directions. Each element is equipped with corresponding guide vanes or the like, liquid feeds, drive means, Axle, rods and ring provided. In such cases, all rows of bars in each of the two units run in the same way Direction and the two units of opposite direction. ,

In another embodiment, as shown in FIG. 3 is, each row of bars revolves in the opposite direction to the adjacent row of bars ",

As mentioned _t beruht.der-cleaning effect of the filter unit on the constantly occurring touching wetted filter rods and particulate matter. It is therefore of the greatest importance that the direction of rotation of the rods is as far as possible at right angles to the direction of flow of the air.

In the embodiments where a number of rows of bars in in the same direction, cannot be avoided *, in spite of

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2. line 3. Il 4th Il 5. ti

Appropriate application of guide vanes that induces the rotation of the rods and increases the rotation of the Air flow during its passage through the filter unit. The success of this is that the first row of bars, which is most effective, and the effectiveness of the further row of rods decreases increasingly until it reaches the last row of members is negligible.

The probable distribution of the effectiveness of the rows of rods as a percentage of the total filter effectiveness results from the following list:

1st row 50 %
30 %
15 ° / o

4 %

1 %

It follows from this that it is of little value to increase the number of rows of bars, because it only increases one Energy consumption is connected as long as a number of these rows of rods one behind the other have the same direction of rotation and the last row of rods of the filter unit acts as a rotor in a fan, which the air radially outwards! pushes away from the axis of rotation and presses against the ring and the wall of the gas line without causing any significant There is contact between the rods and the suspended matter “The suspended matter then moves with dom Gas flow at almost the same speed as the rods and arrive under the influence of centrifugal force to the outer side of the rods without them sticking to the rods themselves.

It is obvious that with such arrangements a substantial amount of energy is consumed in order to to flower radially outwards from the filter unit, which -ij-

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in turn leads to complicated problems and not to purify the air. -, -

The preferred embodiment of the device according to the invention eliminates these problems and this means that each row of rods rotates due to the fact respect to the adjacent in the opposite direction. In this way, the air can be brought into rotation. Essentially the same cleaning effect is produced by each row of rods and the number of rod rows can consequently be reduced without reducing the cleaning effect of the system and / or a significant amount of energy saved and / or the same number Rows of rods are used for a significantly improved cleaning effect, without increased energy consumption being the result. The ability of this modified embodiment of the device according to the invention to absorb gas from the air is also improved due to a number of factors which have already been explained above for the separation of suspended matter from the air «,

The components referred to in the FIG _o 3 which correspond substantially to those of Figure 1 _a, · are provided with the same number and the letters A, they refer to the w'enn ■ second unit.

In such a preferred embodiment, it is advantageous that each row of rods is rotatable in the opposite direction to its adjacent row of rods. This is achieved in that a number of rows of rods are arranged on an axis (first main part of the filter unit) and the same number of rows of rods are arranged on the ring (second part of the filter unit). The direction of rotation of the axis and ring is directed against each other, so that the rows of bars ^d it

1. Main part run in the opposite line as the one ^; ""'

2, main part. '' ^s __,

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The first main part is composed of the motor 10 mounted centrally in the vanes 18 for driving the shaft 12, the has a series of rods 7 which extend radially up extend close to the ring 14. The ring 14 is a particularly important component of the second main part of FIG Filter device. It comprises a pipe 1A for liquid supply through the hollow shaft of the drive motor 1OA, which hangs centrally over the blades 18Ai and a shaft 12A owns, which in turn have a spider 13, a support ring 15 which is supported on the ring 14. The Ring 14 can be constructed from a number of elements and fitted into the interrupted wall of the gas line 2 together with the support ring 15 with only a very narrow clearance 19. The ring 14 carries different rows of rods 7A, the extend radially inward to close to the axis 12 so that the rows of bars 7, 7A in opposite directions Direction are rotatable. The respective parts of the first unit correspond to those of the second unit with the difference, that the first without and the second with A are marked.

The main filter part 8 with motor 10 and blades 18 has the axle 12, which are held together by the bolts 11 and spacers that the axle parts with the Press together axle plates 17, which form the carrier for the row of rods 7, as well as the other axle plates 17 ', the prevent the gas flow from penetrating through the axle,

The ring 14 is also expediently divided into different sections. Each section forms the carrier for a row of rods 7 A, the rods moving radially extend inside of the ring 14. This only lets in small play 19 and can optionally have openings 20.

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As mentioned, the ring 14 can be fixed at one end with the support ring 15 carried by the star 13 mounted on the axis 12A in connection with the motor 1OA.

The rods 7A can be at their inner ends, so where they Get as close as possible to axle 12 and be stiffened with reinforcement rings 7ÄR. These reinforcement rings 7AR are alternating with and between the axle plates 17 and arranged essentially in the same radial plane to the axle plates 17 '.

This embodiment of a filter unit with two main parts 8, 8A is advantageous because the axle plates 17 only small central openings for the passage of the lines and / or 1A for liquid to at least one atomizer exhibit. They can be divided into one or more treatment zones and, if necessary, also a drying zone 23 can be provided after the treatment zone or zones in which no liquid atomization takes place. the Axle plates 17 with a large central opening are indicated in FIG. 3.

According to FIG. 1, the filter unit from the parts 8, 8A is installed in a gas line 2 which has a circular cross-section at least in the area around the filter. Blowers or ventilators with their drive mechanisms, for example electric motors (not shown in FIG. 3), can be provided. It can also be seen from FIG. 3 that the filter parts 8, 8A are driven by the motors 10, 10A. are driven and lines, 1, -IA for a possible liquid feeder ^; are preceded. These can be divided into one or more Zor ;; t; 3uborn 22nd end on, of which only one is in the middle part of the

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Filters is shown.

In this and in most embodiments it is advantageous, wings 18, 18A on the centrally arranged components 9, 9A for supporting the motors 10, 10A to be provided. In addition, the wings 18, 18A act to influence the direction of the air.

The shafts of the motors 10, 10A go over into the axes 12, 12A. The rows of bars at an axial distance from the axis 12 extend radially to close to the ring 14. The axis 12A carries the star or wreath 13 and on it a support ring 15, the the ring 14 is supported. Support ring 15 and sections of the ring are fitted into the interrupted wall of the air duct 2 and have essentially the same working cross-section.

The divided ring 14 carried by the support ring 15 and the spider 13 on the shaft 12A with motor 10A is divided into sections which carry the rows of bars 7A. These bars extend radially inward towards the axis 12, the inner ends of each row being stiffened by a stiffening ring 7AR. From Fig. 3, it follows that this Verdärkungsringe are located alternately between the axle plates and esentlichen in \\ ^r in the same radial plane as the bar rows are.

The axle plates 17, which are then alternately arranged in the axial direction between the axle plates 17 'and have the above-mentioned reinforcing ring 7AR for stiffening the row of rods in the immediate vicinity of the axle 12, are also used for the; Mounting of the bar graters 7 and are shown in FIG. 3 in two embodiments. Eire execution!;:; - shape with larger central opening for the application ■ "usMiriincn ¹ 'with a central atomizer, like e 22 ,; x'.r feed ilcr

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Liquid to the axis 12 and atomization in the gas stream within the gas line 2. The second embodiment of the axis plates has essentially the same outer diameter as the first embodiment but only a small central opening to prevent atomized liquid from entering the adjacent zones, e.g. can penetrate into the separator zone 23 according to FIG. 3 _f. This zone serves as a dry zone without supply of liquid or ■; possibly using a different liquid. The axle plates 17 have only a small mean diameter and are preferably designed so that the gas or air flow in the gas line 2 can only _{escape to a very small extent n} through the annular space between the axle 12 and the walls of the gas line 2. They form a secondary circle through the interior of the axle 12 without being exposed to the cleaning effect of the rotating rods. The axle plates 17 'are also provided for the same purpose, alternating between the axle plates 17. These only serve to inhibit the gas flow which would otherwise penetrate into the secondary circle through the axle. This differs from the axle plates 17, the main purpose of which is to support the rows of bars, except for the fact that the embodiment with a small central opening can also be viewed as a guide element.

In Fig. 3 it is shown that the first main part of the filter unit, i.e. Motor 10, axle 12 with bolt 11, axle plates with rows of bars 7 and axle plates 17 'in one direction run while the other main part with motor 10A, axis 12A, spider 13, support ring 15 and the elements of the split ring with their rows of bars 7A and reinforcing rings fi 7AR revolve in the opposite direction.

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These parts, ie the axle plates 17 with either small or large mean diameter and the plates 17 ^l , the number of rows of bars 7, 7A with reinforcing rings 7AR and the selection of zones and the number of zones for treatment with liquid and optionally dry zones as well as the type of atomization, for example with individual nozzles or perforated tubes with a larger axle diameter ₍ are selected with a view to the working conditions and are known per se.

The mixture of liquid and entrained particles and other co-constituents, which either go to the outside areas the rows of rods is pushed or flows along the rows of rods 7Λ under the action of centrifugal force is to the Sections of the ring 14 out, penetrates this and / or the Ring 14 in the same way as explained for FIG was by inserting through the slot 19 between the support ring 1f5 and the wall of the gas pipe 2 flows. The mixture of the liquid with the impurities can also leak out between the free end of the ring 14 and the wall of the Gas pipe and / or through perforations or small openings 20 in or between the different sections of the ring In this way, the mixture of the liquid comes with it the impurities in the collection chamber I6, as already done is shown in Fig. 1, here again a liquid seal 21 is provided.

For the deposition in a drying zone 23 using axle plates 17 and / or] '/' each with small central openings, the atomized liquid is prevented to a great extent from penetrating into the drying zone, so that a number of rods 7, 7A in this zone are essentially dry and only serve to remove the liquid mist from the gas stream. As already mentioned above, in the ¹ drying zone 23 the atomization of another liquid

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be carried out, for example such a _T which is "particularly suitable for washing out the gaseous impurities beyond the already existing separation of the suspended matter with the help of water in the preceding zones. If several liquids _T are used, the necessary feed lines through the hollow axis are necessary, ,

There are of course_ other ways to operate the Filter devices. According to Figures 1 and 3 instead of the Motors within the system, these can be outside the gas line. The force can pass through the filter a wide variety of drives are transmitted.

The term 'rotation' in connection with the rotating movement of the bars 7, "7A in the corresponding rows also includes an oscillation in such a way that the direction of oscillation for each row in the opposite direction to the neighboring one Direction takes place. Such an embodiment is driven by an eccentric on the outside of the corresponding rings 14 on. The ring segments and the / ichf-vplatten 17, 17 'can have the same shape «For · the above embodiments a hollow axle is mounted, both for support (axis for vibration) and for the supply line to the atomizer. The pipe or the axis anoints can be perforated and with it as a nozzle or anger,

Claims

SAD.

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Claims (16)

Patent claims above c e 1, device for removing solid, liquid and / or gaseous contaminants from air or others Gases built up from a tubular gas line "die is optionally provided with a fan or blower for forced gas flow, at least one rotatable filter element has with a corresponding drive and the gas line in the area of the filter unit like this one has a circular cross-section and each filter unit is made up of at least one centrally arranged axis and at least one peripherally arranged ring together with a network of rods extending radially across the extend all or the substantial part of the annular space between the axis and the ring and to it serve, a liquid that is either atomized or near the axis and / or in front of the filternnheit in the gas line is introduced under the influence of the To hold the centrifugal force and the surface tension and to let it flow outwards along the rods than Liquid film j to which the impurities adhere, and for collecting the liquid laden with the impurities outside the ring of the filter unit at least a collecting chamber is provided, characterized in that the ring (i4) has a diameter approximately that of the inner diameter of the gas line (2) and the Walls of the gas line for receiving the ring (^ are interrupted and leave only a small slot (19) free for the Passage of the liquid mixture into the one around it Collection canal (161 309821 / 0187- 1A-42 - 21 - 2. Apparatus according to claim 1, characterized in that guide vanes (18, 18A) in the gas line (2) are provided just in front of and / or behind the filter unit. 3. Apparatus according to claim 1 or 2, characterized in that a number of filter elements are arranged axially in series one behind the other and rotatable in the opposite direction. ■ r 4. Device "according to claim 1 to 3, characterized characterized in that the collecting chamber (16) seals gas-tight. 5. Apparatus according to claim 1 to 4, characterized in that the ring (14) has a channel or Z-shaped cross section in the direction of the axis and the ^! Web part has an outwardly inclined part and in its largest peripheral part perforations (20) to. Entry of the liquid mixture into the collection chamber (16). 6. Apparatus according to claim 1 to 5, characterized geke η η ζ ei ^!> ch net that the filter unit has at least one hollow axis' ^ f2 / · 12A) ° and supply lines (1, 1A) for the introduction of at least one liquid into the corresponding zones. 7. Apparatus according to claim 1 to 6, characterized in that the one to the washing zones a drying zone (23) is connected. 8. Apparatus according to claim 1 to 7, characterized in that a before the filter unit Atomizer (3) is provided. 309821/0897 1A-42 307 - 22 - 9. Apparatus according to claim 8, characterized in that the atomizer (3) and / or (22) are single nozzles or perforated tubes. 10. Apparatus according to claim 1 "to 9, characterized in g e that the ring (14) has a greater width in the axial direction than the rows of bars (7, 7A). 11. The device according to claim 1 constructed from two Filter elements (8, 8A) rotatable axially one behind the other in opposite directions, marked by a number of rows of rods (7) on a central axis (12), which extend radially outwards to immediately on the ring (14) or rows of rods (7A) extending radially inwardly to directly on the Axis (12) extend from ring 14 and the rows of rings of rods (7, 7A) are alternately arranged and across the drive mechanisms (10, 10A) are rotatable in opposite directions. 12. The apparatus of claim 11, characterized ge indicates that the filter elements (8, 8A) are equipped with tubes (1, 1A) for the supply of liquids are. 13. Apparatus according to claim 11 and 12, characterized in that the ring (14) in sections is divided, each designed as a carrier for a number of rods (7A) and the sections by narrow Slots or perforations (19) are separated. 14. The device according to claim 13, characterized in that the ring (14) on its inner part is supported on a support ring (15), which in turn is mounted on a spider (13) on the axis (12A) with a drive mechanism (10A) is fixed. - 309821/0897 ' 1Ä-42 15. The device according to claim 11 Ms 14 _S, characterized in that the rods (JA) are stiffened at their inner end by a reinforcing ring (7Aß), the reinforcing rings (7AR) each between axle plates (17) which the rods ■, (? ) carry * are arranged. 16. The device according to claim 11 to 15, characterized in that the axle plates (17) .Only small central opening for the passage of the lines (1A) -to have at least one atomizer (22), which the filter 'unit into one or more treatment zones and optionally a drying zone (23) at the end of the treatment zones subdivide. 309821/0897 Blank page