DE9215467U1 - Filters for cleaning liquids - Google Patents

Description

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The innovation relates to a filter for cleaning liquids, in particular for separating oil and oily substances from oil-water emulsions, consisting of a container that can be filled with activated carbon or the like during use, with a connection for supplying the liquid to be cleaned to the container and with a drain for discharging the cleaned liquid from the container.

In a known filter system, the dirty water is fed via a pump to the connection located in the upper part of the container and from there via a pipe into the lower part of the container, where the dirty water exits and the filtering begins. The liquid is fed under pressure from bottom to top through the activated carbon filling and is filtered in the process, i.e. the activated carbon absorbs the oil or oil-containing substances until it is saturated. The cleaned liquid is fed from the drain located at the top for reuse.

The container is built into a table in an upright design so that the used activated carbon can be removed via a lockable opening at the bottom of the container in the table space at a distance above the floor or ground level by placing a suitable transport container under the opening to collect the used activated carbon that flows out. To fill in fresh activated carbon, a lid that closes the top of the container is removed and activated carbon is filled in from a transport container.

This filter system is used, for example, to clean water-oil emulsions that arise when using penetrating oil in non-destructive crack testing of cast and forged parts, and especially when

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washing the penetrating oil with water. The water purified in the above manner is fed to a container for intermediate storage and from there via a pump to a spray gun for reuse in the 5 crack test.

The well-known container is made of stainless steel sheet. It is mounted stationary in the table and has a capacity of approx. 75 kg of activated carbon. Removing the used activated carbon and filling the container with fresh activated carbon is associated with a considerable dust and odor nuisance in the area around the filter system. In addition, removing the used activated carbon and cleaning the container before filling in fresh activated carbon is an unpleasant task for the operating personnel. The same applies to filling in the fresh activated carbon, which is associated with unpleasant dust development.

In addition, appropriate transport containers are needed for the removal of the used activated carbon and additional transport containers for the delivery and temporary storage of the fresh activated carbon. Finally, appropriate equipment is also needed for filling the fresh activated carbon into the container used as a filter.

The space required by the container at the site of use is considerable. In addition, the material and manufacturing costs are high, especially since a number of transport containers, filling devices, etc. are needed in addition to the actual filter system. Finally, the handling associated with transporting the activated carbon to and from the site of use is also relatively labor-intensive.

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The task is therefore to create a filter system in which fresh activated carbon is often used and used activated carbon must be removed, in which the manufacturing effort and, above all, the user problems during transport and replacement of the activated carbon filling are significantly reduced.

This task is solved in accordance with the innovation by a filter for the filter system, which is designed in such a way that - in use - several containers can be stacked on top of one another and connected by means of connecting lines to form a multi-stage filter system in such a way that the liquid to be cleaned, which is conveyed into the uppermost container via the feed connection, passes through the containers and their activated carbon fillings one after the other and exits the filter system via the drain of the lowest container.

The core of the innovation is therefore a new container with which the desired filter system can be manufactured as a kit by placing one, two, three or more containers on top of each other to form a filter tower and connecting them to form a multi-stage filter system using connecting lines, depending on the filter volume required. The individual containers of a filter tower are easy to handle, for example by having a volume of 50 liters.

The space requirement of such a filter tower is naturally small, since its base area is optimally used in relation to the total filter volume.

It is very important that the liquid to be cleaned, which is fed into the container at a connection at the top, under the influence of gravity, flows through the container and

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so that the activated carbon filling flows from top to bottom and exits the container again via a drain located on the bottom of the container. In this way, only short connecting lines - optionally hoses or pipes or the like - are needed to transfer the liquid from one container to the next. The feed connection of the top container in the filter tower is used to connect the feed line, in which the liquid to be cleaned is pumped upwards by means of a pump. The drain of the bottom container is used to remove the cleaned liquid. In addition, the connection and drain of containers stacked directly on top of one another are each connected to one of the connecting lines, so that a constant flow through the filter system is guaranteed.

A decisive advantage of the new container and the tower-like filter system that can be manufactured using a modular system is that not only is the structure of the filter system much simpler than the previously known system, but that handling when replacing the activated carbon filling of the individual container is made much easier for the user and the contamination that would otherwise occur can be completely avoided. This is because the containers filled with activated carbon that make up the filter system can simultaneously serve as containers for the delivery of fresh activated carbon and for the removal of used activated carbon and finally for the temporary storage of both used and fresh activated carbon at the user's premises.

The new container therefore preferably has a dual function, which only requires the removal or connection of the connecting lines when replacing

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Containers with used activated carbon and when replacing containers with fresh activated carbon. One can also limit oneself to the perception of the manufacturing advantages if the filter tower formed from containers in accordance with the innovation is used stationary for special reasons and the filter material is to be replaced on site.

The material and manufacturing costs are extremely reduced compared to the known filter system, because the containers stacked on top of each other form a self-supporting filter tower that is easily accessible from all sides without any additional aids such as racks, tables or the like. The cost-benefit ratio of the innovative solution is therefore particularly high, especially when you compare it with the manufacturing and operating costs and the handling effort of conventional filter systems.

It goes without saying that the filter according to the innovation and in particular the filter systems that can be produced with it are in no way limited to the use in cleaning the water-oil emulsion that arises during non-destructive material testing. Instead of activated carbon, other filter materials such as chalk or the like can also be used, and instead of emulsions, other liquids can also be cleaned by allowing them to pass through the stages of the filter system according to the innovation.

Another advantage is that, following the innovation, a suitable filter volume can be achieved for every requirement using a single container size, by simply using the required number of containers

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stacks them on top of each other and connects them to each other, if necessary, two or more filter towers can be placed next to each other and if necessary, two or more filter towers can be connected to each other if the respective filtering purpose allows or makes it necessary.

A very important development of the innovation is that the connecting lines are easy to connect and easy to detach and remove. This is because the handling when replacing the containers of a filter system should be as simple and easy as possible, and the containers should be transported to and from the system without any attached parts if possible.

Another key feature of the innovation is a further development in which a sieve bottom is installed at a distance above the bottom of the container, on which the activated carbon filling rests. This space is essential for an unhindered transfer of the liquid from one container to the other when it has reached the bottom of one container. Above all, it also ensures that the drain opening in the bottom of the container cannot become blocked. The sieve bottom is designed in such a way that it can take the weight of the activated carbon filling, but the liquid can easily flow through it.

To clean the container thoroughly, the sieve bottom should be easy to remove from the container and it should be just as easy to reinsert it into the empty container.

According to the new regulations, the upper container opening should be able to be closed with an easily removable lid. This and the other features relating to the container structure are also essential for the removal

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emptying and refilling the container with filter material. This is conveniently done by the activated carbon supplier in appropriately equipped rooms. The container is opened by removing the lid, emptied by tipping out the used activated carbon, cleaned with an appropriate liquid, for which the sieve bottom can be conveniently removed, and then refilled with fresh activated carbon and closed again with the lid. These processes can easily be automated. The used activated carbon is professionally disposed of and reused.

According to the innovation, it is also provided that a supply line can be connected to the connection of the top container, in which a pump is located to pump up the liquid to be cleaned. The pump is connected to a corresponding intermediate container to supply the liquid to be cleaned, into which the liquid, such as a water-oil emulsion, is introduced immediately after it is created.

A particular advantage of the new container is that it can be made of plastic and should have an essentially circular cross-section. Since the filter system that can be produced with the new container works without pressure, i.e. follows the principle of gravity, standard plastic containers can be used, which further reduces the manufacturing costs considerably, and the low weight of the plastic container simplifies and facilitates transport to and from the container.

Preferably, a 50-litre container is used

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according to Euro standard, which has a high degree of dimensional stability and is commercially available at relatively low cost. The conversion for the new purpose is practically limited to the installation of the 5 two openings for the connection and the drain and the installation of the corresponding connection and drain nozzles or connecting lines. The new container is therefore characterized by a first opening in the upper part for the connection and a second opening in the lower part of the container for the drain.

A shut-off valve and a pressure switch should ideally be installed in the supply line. The pressure switch should ensure above all that the liquid throughput in the filter system is not higher than 200 l/h. Otherwise, the liquid to be cleaned will not have sufficient residence time in the filter material.

When in use, the sieve bottom should rest on the lower bead of the Euro-standard container or, if another container is used, be supported accordingly. According to the new design, the sieve bottom preferably consists of a perforated plate and a fine filter arranged on top of it. The perforated plate ensures sufficient load-bearing capacity and the fine filter prevents activated carbon crumbs or similar from reaching the bottom of the container and from there possibly to the container drain.

The sieve bottom should be easy to insert into and remove from the container, so that a foldable sieve bottom structure made up of two halves is appropriate for this purpose.

According to the innovation, a distribution pipe or similar, which can be arranged so that it can be easily pulled out, is to be attached to the connection of the container on the inside to distribute the

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supplied liquid across the cross-section of the activated carbon filling. The distributor pipe, which is best made up of a simple pipe socket with holes in the wall, should be pulled out of the container with the used filling when the containers are replaced and then reinserted into the container with the fresh activated carbon filling. However, it can also be attached to the inside of the container wall, for example on a connecting socket, and remain in the container when the filling is replaced.

According to the innovation, it is also provided that the connecting lines consist of elbows, preferably made of plastic, with union screw rings on the connections or on the drain, and that these are used to connect a connection on the upper part of a container with a drain on the lower part of the next higher container. Connecting lines made of pipe elbows with union screw rings also allow for extremely simple handling when replacing the containers, without requiring special materials or costs.

According to the new regulations, transport caps should be able to be placed on the screw connections of the container at the connections and drains in order to securely close the container openings during the transport of the containers to and from the site.

Finally, the new design provides that the container can be placed on a standard barrel trolley, so that a filter tower made up of several containers can be easily moved as a whole and even hard-to-reach places can be used as the location for the filter system if the tower can be moved into a free space using the barrel trolley to handle the containers, for example when exchanging them.

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An embodiment of the innovation is explained in more detail below with reference to the drawings. In the drawings:
05

Fig. 1 is a view of a filter tower formed from three containers;

Fig. 2 is a sectional view of the container in the area of a supply connection with a distributor pipe;

Fig. 3 a sectional view of the container in the area of a drain with part of a connected pipe bend as a connecting line; 15

Fig. 4 is a sectional view of a sieve bottom that can be inserted into the container.

In the embodiment according to Fig. 1, three containers 2 are stacked on top of each other to form a filter tower 1 of a filter system, so that the bottom of each container engages with the removable lid 3 of the next lower container, thus causing centering.

Each container 2 is a 50-liter container made of plastic in accordance with EURO standards. To form a supply connection in the upper part of the container, an opening 20 (see Fig. 2) is provided in the container wall 21 and in the lower part of the container an opening 22 (see Fig. 3) is provided to form a drain 5.

A connecting line 6 designed as a pipe bend can be easily and quickly attached to the outlet 5 of each container using a union screw ring 9 to form a seal on a socket 30. The exact structure of the outlet

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5 is described in connection with Fig. 3. In the same way, the other end of the connecting line

6 is also connected in a simple, sealing manner by means of a union screw ring 9 to the corresponding sleeve 3 0 of the feed connection 4 of the next lower container 2. The structure of the feed connection 4 is described in detail in connection with Fig. 2.

The supply connection 4 of the uppermost container 2 serves for the easy and simple connection of a supply line 11 which originates from a pump 14 and in which a shut-off valve 12 and a pressure switch 13 are arranged.

The drain 5 of the lowest container 2, which in most cases is located on the floor 16, is provided with a drain line 15 which leads to a storage container (not shown).

Just above the outlet 5 of the container 2 there is a sieve bottom 7, shown in dashed lines in Fig. 1, which is supported on the lower edge 23 of the lower bead 8 of the container wall 21 all around the container wall 21 in the manner shown in Fig. 4.

As shown in Fig. 4, the sieve bottom 7 consists of two equal halves 7a, 7b, each of which has a semicircular shape and is hinged together by means of a hinge strip. Each of the two halves 7a, 7b consists of a perforated plate 25 made of plastic with through-openings 26 and a fine filter 27 arranged on the surface and pulled around and fastened laterally over each half 7a, 7b, which is held on the outside by means of an edge strip 28 which is screwed to the perforated plate 25, for example.

From the feed connection 4 of each container 2 extends

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As shown in dashed lines in Fig. 1 and partially in Fig. 2, there is a distributor pipe 10 made of plastic with outlet openings 29 approximately in the direction of a diameter of the circular cross-section of each container 2. The distributor pipe 10 can be easily pulled out of the container 2 after loosening the corresponding union screw ring 9 and removing the connecting line 6. In the embodiment shown, however, the distributor pipe 10 is fastened to remain in the container 2.

In each of the containers 2 there is an activated carbon filling 18, indicated in the uppermost container 2 in Fig. 1 with a pattern of wavy lines, which is supported by the sieve bottom 7 in each container 2 and fills the container up to the maximum filling level 17, i.e. approximately until it reaches the respective feed connection 4.

The embodiment shown is a filter system for cleaning oil-water emulsions, which arise when washing off penetrating oil used in non-destructive crack testing of cast and forged workpieces. For this purpose, the oil-water emulsion passes through the filter system, whereby the activated carbon absorbs the oil until it is saturated and the water flowing out of the filter system can be reused for material testing.

When the filter system is in operation, the liquid to be cleaned is pumped from an intermediate container (not shown) by the pump 14 via the line 11 into the uppermost container 2 via its feed connection 4. The liquid is distributed over the cross-section of the activated carbon filling 18 by the distributor pipe 10, flows gradually during

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after a certain dwell time through the activated carbon filling 18 to the sieve bottom 7, where it flows through the passage openings 26 into the free space between the container bottom and the sieve bottom 7. From here it passes via the drain 5 and the connecting line 6 in the form of the pipe bend through the feed connection 4 of the next lower container 2 into its distributor pipe 10 and from here into the activated carbon filling 18, so that in the second container 2 a filtering takes place again as in a second filter stage. After passing through the second container 2, the liquid enters the lowest container 2 via the lower connecting line 6, where the filtering is completed and any remaining oil residues in the activated carbon filling 18 are filtered out, so that the liquid leaves the drain 5 of the lowest container 2 as oil-free water and can be fed for reuse via the drain line 15.

The pressure switch 13 ensures that the liquid flow rate does not exceed 200 liters per hour, so that the liquid does not flow through the activated carbon fillings 18 too quickly and the activated carbon cannot become saturated with oil.

Approximately 25 kg of activated carbon form an activated carbon filling in each container 2. To accommodate this weight, the perforated plate 25 of the sieve bottom 7 has a thickness of approx.

10 mm. The fine sieve has a mesh size of approx. 0.4 mm so that larger particles are retained and cannot get into the free space between the container bottom and the sieve bottom 7. So that the connections of the connecting lines 6 and the feed line

11 and the drain line 15 are easily accessible, it is advisable to use the union screw

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rings 9 recognizable connection points by 9 0° relative to the supply line 11 or, conversely, to provide the supply line 11 with a quarter-circle-sized curved piece at its upper end in order to achieve the aforementioned 5 angular offset.

The degree of oil saturation of the activated carbon fillings 18 decreases from container 2 to container 2 from top to bottom, as well as within the individual containers 2 themselves. Therefore, after a certain period of use, the bottom container 2 is replaced with the top container 2, so that the relatively unused activated carbon filling 18 of the previously bottom container 2 is now used in the first filter stage and in this way a relatively uniform saturation of the activated carbon fillings 18 of the three containers 2 stacked on top of one another is finally achieved. To do this, simply loosen the union screw rings 9 on the top and bottom containers 2, remove the supply line 11, the top end of the upper connecting line 6, as well as the bottom end of the lower connecting line 6 and the drain line 15. After replacing the top and bottom containers 2, the aforementioned lines and connecting parts are connected to the newly replaced containers using the same union screw rings 9. The filter tower shown, including the pump 14, only takes up one

2 Installation area of less than 1 m.

When the activated carbon fillings 18 in the three containers are saturated and no more oil can be filtered out, the liquid entering the drain line 15 at the lowest drain 5 begins to turn red, with the red color coming from the penetrating oil. For control purposes, a corresponding sight glass can be provided at the beginning of the drain line 15 or

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but the cable itself must be made of a transparent plastic.

When the activated carbon fillings 18 of the filter system are saturated, the three containers 2 of the filter tower are very easily replaced with three containers 2 filled with fresh activated carbon. To do this, the union screw rings 9 are loosened, the connecting lines 6 as well as the feed line 11 and the drain line 15 are removed and, if necessary, the three distributor pipes 10 are pulled out of the containers 2. Transport caps (not shown) are now screwed onto the sleeves 30 of the feed connection 4 and the drain 5 of each of the three containers 2 to seal them so that any liquid that may still drip from the activated carbon fillings 18 cannot escape from one of the drains 5. Each of the containers 2 is now sealed all around and can therefore be easily handled without special care and transported to a location where, after emptying out the used activated carbon filling and cleaning the container 2, a fresh activated carbon filling can be inserted and the container 2 can be brought back to a location and reinserted into a filter system.

The foldable sieve bottom 7 can be easily removed and inserted to clean the container 2 or to replace the sieve bottom 7.

In the illustrated embodiment, the supply connection 4 according to Fig. 2 is manufactured as follows:

A connecting piece 31 is inserted and secured from the inside into the opening 20 of the container wall 21, whereby an internal flange 33 of the connecting piece

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31, as an adhesive layer 32 is intended to illustrate, is attached to the inside of the container wall 21. The sleeve 30, which is provided with an internal thread and an external thread 36, is screwed onto a section 34 of the connecting piece 31 protruding outwards from the container wall 21 and having an external thread 35, and, as a further adhesive layer 37 is intended to illustrate, is attached in a sealing manner to the outer wall of the container wall 21 and also to the outer section 34. The distributor pipe, which has the outlet openings 29, is placed on the inside of an inner section 38 of the connecting piece 31 and is also attached by gluing. If the distributor pipe 10 is to be easily pulled out, it is not attached to the connecting piece 31, but to a connecting pipe piece 39, which will be explained later, from where it extends through the connecting piece 31, with the distributor pipe 10 being guided and held in the connecting piece 31. The aforementioned parts are made exclusively of plastic and form a unit that is attached to the container wall 21 and remains there, including the distributor pipe 10, if this is attached to the inner section 38 of the connecting piece 31, as shown.

At each end of each connecting line 6, a connecting pipe section 39 with a flange 40 is attached, preferably by gluing, in the manner shown in the drawing. Before gluing, the union screw ring 9 with an internal thread intended for the respective supply connection 4 is arranged, which serves to connect the connecting line 6 to the supply connection 4. To connect the end of the connecting line 6 shown in the drawing to the sleeve 30, only the flange 40 needs to be brought into the connecting position and the union screw ring 9 screwed onto the sleeve 30

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until the flange 40 is in sealing contact with the front face of the sleeve 30, whereby an annular seal 41, which is secured in a seat 42 on the front face of the sleeve 30, ensures a sealing connection.

5 The components described above are also made of plastic, with the exception of the seal 41. For container transport, a transport cap (not shown) is screwed onto the sleeve 3 0 instead of the union screw ring 9.

The drain 5 shown in Fig. 3 is basically constructed in the same way as the supply connection 4, as the drawing shows, so that a repeated description of the corresponding components is omitted. In the drain 5, the connection piece 31 ends inside with the flange 33, since the distributor pipe 10 on the drain 5 is omitted.

It goes without saying that the innovation is not limited to a three-stage filter system of the type shown. The introduction to the description has already mentioned in detail the versatility of the containers 2, from which filter systems can be assembled like a kit. There will also be no repetition of the numerous other advantages of the innovation at this point.

Claims (20)

1. Filter for cleaning liquids, in particular 5 for separating oil and oily substances from oil-water emulsions, consisting of a container filled with activated carbon or the like during use with a connection for feeding the liquid to be cleaned to the container and with a drain for draining the cleaned liquid from the container, characterized by a construction of the container (2) in such a way that - during use - several containers (2) can be stacked on top of one another and connected to a multi-stage filter system (1) by means of connecting lines (6) in such a way that the liquid to be cleaned, which is conveyed into the uppermost container (2) via the feed connection (4), passes through the containers (2) and their activated carbon fillings (18) one after the other and exits the filter system (1) via the drain (5) of the lowest container (2). 2. Filter according to claim 1, characterized in that the connecting lines (6) are easy to connect and easy to detach. 3. Filter according to claim 1 or 2, characterized in that a sieve bottom (7) is attached at a distance above the bottom of the container (2), on which the activated carbon filling (18) rests. 4. Filter according to claim 3, characterized in that the sieve bottom (7) can be inserted into the empty container (2) and easily removed therefrom. 35 is removable. 3214.4- - 2 -.!.·*«· &Lgr;. .!♦*11&ngr;&idiagr;*1.1992 5. Filter according to one or more of claims 1 - 4, characterized in that the opening of the filter (2) can be closed with an easily removable cover (3). 6. Filter according to one or more of claims 1 - 5, characterized in that a feed line (11) can be connected to the feed connection (4) of the uppermost container (2), in which a pump (14) for pumping up the liquid to be cleaned is located. 7. Filter according to one or more of claims 1 - 6, characterized in that the container (2) consists of plastic and has a substantially circular cross-section. 8. Filter according to claim 7, characterized in that g e k e &eegr;&eegr; - indicates that the container (2) corresponds to a 50 litre container according to EURO standard. 9. Filter according to one or more of claims 1 - 7, characterized by a first opening (20) in the upper part and a second opening (22) in the lower part of the container (2) for the supply connection (4) or for the drain (5) of the container (2). 10. Filter according to one or more of claims 1-9, characterized in that a shut-off valve (12) and a pressure switch (13) are arranged in the supply line (11). 11. Filter according to one or more of claims 1-10, characterized in that the sieve —3— 3214.4- - 3 -.:."..' .:« &ngr; *tl TTl. 1992 base (7) rests on the lower bead (8) of the container (2) during use. 12. Filter according to one or more of the preceding 5 claims, characterized in that the sieve bottom (7) consists of a perforated plate (25) and a fine filter (27) arranged on this. 13. Filter according to one or more of the preceding claims, characterized in that the sieve bottom (7) is foldable and is formed from two halves (7a, 7b). 14. Filter according to one or more of the preceding claims, characterized in that a distributor pipe (10), which can be easily pulled out, or the like, for distributing the supplied liquid over the cross section of the activated carbon filling (18) is connected to the supply connection (4) of the container (2) on the inside. 15. Filter according to one or more of the preceding claims, characterized in that the connecting lines (6) consist of pipe bends with union screw rings (9) that can be screwed onto sleeves (30) in a sealing manner at each supply connection (4) or outlet (5), and with these a supply connection (4) on the upper part of a container (2) and with an outlet (5) on the lower part of the next higher container (2) is to be connected. 16. Filter according to one or more of the preceding claims, characterized in that transport caps are placed on the sleeves (30) of the container (2) at the supply connection (4) and the drain (5) 3214.4- _ 4 -I . ♦* * .·. *l*U:ii.l992 can be screwed on to seal. 17. Filter according to one or more of the preceding claims, characterized in that the container (2) or several containers (2) stacked on top of one another can be placed on a barrel trolley. 18. Filter according to one or more of the preceding claims, characterized in that the supply connection (4) and the drain (5) each consist of a connecting piece (31) fastened in a container opening (20) or (22) and a sleeve (30) fastened externally to the connecting piece (31), onto the external thread (36) of which the union screw ring (9) for connecting the connecting line (6) or a transport cap can be screwed sealingly. 19. Filter according to claim 18, characterized in that the distributor pipe (10) is fastened to a radially inwardly projecting inner section (38) of the connecting piece (31). 20. Filter according to claim 18 or 19, characterized in that the connecting line (6) is sealingly connected to the sleeve (30) by means of a flange (40) and a seal (41).