DE1101365B - Device for filtering liquids - Google Patents

Description

For filtering liquids through a granular layer of solids, e.g. B. over a layer of gravel are a Method and apparatus have been described, after which the liquid to be filtered of the filter layer is fed in from above or below or from both ends and the filtered liquid out taken from the interior of the filter layer at a suitable height by means of a drainage system will.

The advantage of this filter device is that you can get through the housed in a container granular filter layer can simultaneously supply the liquid to be filtered from above and below, so that So for a given cross-section of the filter container, twice the filter area is available as with one conventional filter, which is known to only filter from top to bottom. But you can also do that Let the grain size of the filter material increase sharply from top to bottom, so that the space volume for the liquid flowing from bottom to top decreases in the same direction. In this way it is possible to dispose of liquids with a relatively high content of cloudy substances to be filtered off in large quantities enforce before a backwashing of the filter is necessary, since practically the entire pore volume of the filter bed is available and used for the separation of the tri-substances can, while with a normal Ries filter with differently grained gravel, the operational classified by the backwash in the same direction from top to bottom with increasing grain size is, practically only a filtration in the upper layers is possible, because with the usual direction of filtration from top to bottom, the narrower gaps in the upper layer are the quickest to clog and the larger spaces in the lower layers can no longer be effective. You can operate such a filter in two different ways, which may be different can also overlap. One way of working is that the gravel grains practically over the whole filter layer is kept about the same size and that both from above and from below in the Approximately the same amounts of liquid are filtered through over a unit of time. The other, described above Embodiment is that most of the liquid from bottom to top through the Filter layer is guided and only as much liquid passes through from above as the smaller one there Grain size allows it. In this case, the liquid supplied from above is mainly used to To hold the gravel filter bed in its position as a whole.

The drainage system known here for draining off the filtrate consists of a perforated or seated device for filtering
of liquids

Applicant:

Metallgesellschaft Aktiengesellschaft,
Frankfurt / M., Reuterweg 14

Dr. Werner Wisfeld and Alfred Kratz, Frankfurt / M., Have been named as inventors

th, possibly surrounded by a fine wire mesh Pipes that are built into the granular filter mass and their free ends through the walls of the filter housing are for example led laterally to the outside. When the openings in these drainage pipes or the mesh sizes of the surrounding wire network are too large, parts of the granular Filter mass get into the filtrate. If, on the other hand, the openings in the pipes or the mesh sizes of the surrounding wire mesh smaller than the filter material grain size, then due to partial clogging of the Openings through the filter material make the filtration process considerably more difficult, and high pressure losses occur a. The removal of these blockages then makes a premature backwash, and often even an expansion of the drainage system is required. In addition, this is embedded in the filter layer Dissipation system is exposed to strong shear forces of the filter mass, so that very massive and accordingly expensive proppants must be installed. However, these then reduce the effective one Cross-section of the filter and make the flow conditions in the filter layer very confusing.

It has now been found that this filtration method Can be significantly simplified and improved if the system for discharging the filtrate from the Filter layer designed as a small coarse gravel filter and parallel to the direction of flow to be filtered Liquid is arranged in the filter layer.

Gravel bed filters or the like. Sheet filters are usually of a vertical type. In a vertical, preferably cylindrical container, the z. B. is provided with flanged covers on the front sides, is the actual filter layer of a perforated intermediate floor and a coarse-grained intermediate layer carried. The inlets and outlets for the liquid are on the front sides, i. H. to the Lids arranged, but can also laterally, d. H. be arranged on the cylinder jacket.

109 529/459

Claims (6)

3 4 The invention relates to a liquid filter arranged melrinne28, the z. B. from an oblique with granular filter media, which the wall part 29 to be cleaned and a vertical wall part 30 gebil-liquid at the free ends of the filter layer. A sieve bottom 31 is guided with the housing is, the filtrate from the interior of the wall and the inclined wall part 29 an annular channel, Filter layer by means of a drain 5 embedded therein, from which stub 32 to the outside for draining the system is taken. Lead filtrate. The one above the sieve bottom The filter according to the invention is characterized in part of the collecting channel is characterized in the aforementioned way that the drainage system consists of pipes open at the top with several layers 33, 34 of granular material or a channel which fills the walls. The grain size of these layers decreases from the bottom parallel to the direction of filtration, and their grain size upwards in the flow area of the filter layer 25 cannot slide increasingly through the direction of the diverted liquid.
Grain size included. It is particularly suitable for large filter cross-sections The drainage system can e.g. B. from pipes with 15 the arrangement of the drainage shown in Fig. 3 Walls parallel to the direction of filtration exist, organs, the S ¹ ICh as a combination of Fig. 1 and 2 which is introduced from below into the filter mass and results in. these are embedded, and in their in the filter- In this figure 40 denotes the housing ground lying mouths - the granular material on the jacket, 41 the Sameinem arranged on its inside Sieve bottom is arranged. 20 gutter, 42 di'e nozzles for draining off the filtrate, Another embodiment of the invention consists of which can be connected by a ring line, in that on the inner wall of the filter housing in 43 drainage pipes, which according to Fig. 1 from below in the desired height with a granular filter mat- the filter layer are introduced and in the berial there Filled overflow channel attached and with a written way at the top with a fixed or several processes is provided to the outside. 25 layers of fabric are provided. The tubes43 can be elliptical Finally, both embodiments can have a granular cross-section or any other transverse be combined by cutting into a filter housing that ensures good and even distribution the peripheral overflow channel as well as that from below the drainage openings over the filter cross-section Introduced pipes are used. permitted. The figures show three embodiments. 30 The upper edges of the filter layers in the raw 43 of the invention, for example and shown schematically, and the collecting channel 41 are in the same position represents. Height. The tubes 43 are below the sieve bottom, Fig. 1 shows a filter with a central filtrate discharge which carries the filter material, or outside of the in vertical section; Filter housing together in a collecting line Fig. 2 shows a filter with a peripheral filtrate 35 collected, tion, also in vertical section; The filter to be filtered is used to operate the filter Fig. 3 is another embodiment of the inven- tive fluid through the lower and upper an appropriate filter in horizontal section. Finally passed into the housing. A whirlwind of The device according to Fig. 1 consists of a filter layer does not occur here because in the filter vertical, preferably cylindrical container 1, in the housing above and below the same pressure is automatically established as that on a perforated one which is known per se. The solid soil separated from the liquid, e.g. B. a nozzle bottom 3., a granular filter materials are solid layer in the filter layer above and below, z. B. a gravel bed 2 is stored. Between that and can be held therefrom by backwashing in the perforated bottom and the filter layer, distribution layers 3 a, 3 b with coarse 45 can be removed in an upward flow in a known manner. It can be useful from time to time to arrange the grain size. Through connections 4, 5 during this backwashing, also through the filtrate, the liquid to be filtered is diverted from both ends and some rinsing liquid is fed into the filter to press the filter layer. The filtrate is passed through ken in order to divert the grain layers stored in the pipe mouths and / or in a central pipe 6 from the interior of the filter layer of the collecting channel. The 'lower end of the tube 6 leads over 50 loosen. the connection clip 7 to the outside. The top end The filter of the present invention is useful for clarification carries a suitably multi-part filter layer, which is granular from cloudy liquids by filtration is mounted on a sieve bottom 8. The upper layer 9 filter media and also for the execution of ionic This filter layer is so coarse-grained that the grains exchange reactions. In this case take the place the surrounding main layer 2 does not slide through 55 the granular filter mass a suitable ion discharge can. exchange material. The underlying layer 10 is somewhat coarser due to the arrangement and design of the drain Grain size. Further given systems can then be added to the filter according to the invention if coarser grain layers follow, z. B. also about the shear forces that occur during backwashing and re-washing in such a way that the sieve bottom 8 is omitted and the 60 starting of the filter material inevitably occurs. Tube 7 completely filled with a granular material, reduced to a minimum. The in the is. fertilize the drainage system arranged, granular In the device according to Fig. 2, the unmassing takes place in the event of blockages in the drainage taking the filtrate from the filter layer can be easily cleaned by backwashing via a system, peripheral groove on the inner wall of the filter housing. 6 ₅ patent claims The filter housing21 is with. Liquid supply lines CLAIM TO RATE. 22, 23 provided. On the sieve bottom 24 is the filter 1. Liquid filter with granular filter media, layer 25, optionally with the interposition of the fluid to be cleaned to the free known distribution layers 26, 27 are stored. At, ends of the filter layer is fed, the the vertical inner wall of the container is a Sam- 70 filtrate from the inside of the filter layer means I 101 a drainage system embedded therein is removed, characterized in that this System consists of upwardly open pipes or a gutter, the walls of which are parallel to the direction of filtration lie and their mouths lying in the filter mass granular material with increasing in a manner known per se in the direction of flow of the diverted liquid Grain size included. 2. Filter according to claim 1, characterized in that the total cross section of the discharge system 10 to 25% of the cross section of the filter. 3. Filter according to claims 1 and 2, characterized through tubes (6) with a sieve bottom introduced from below and embedded in the filter mass (2) (8) and grain layers (9, 10). 4. Filter according to claims 1 and 2, characterized by the collecting channel (28) on the inside Container circumference, with the sieve bottom (31) and the multilayered grain filling (30). 5. Filter according to claims 1 to 4, characterized in that both tubes (43) and a collecting channel (41) come into use at the same time. 6. Filter according to claims 3 and / or 5, characterized in that the surfaces of the grain layers in the channel (28, 41) and the tubes (6, 43) are at the same height. Considered publications:
German Patent Nos. 963 417, 883 889;
Austrian Patent No. 54,878;
U.S. Patent No. 2,666,741. 1 sheet of drawings © 109 529/459 2.61