Method and device for the treatment of filter residues and washing machine

Abstract

Device (100, 200) for treating filter residues, comprising a device for supplying a pressurized fluid; a housing (2, 22) having a) a first inlet (1, 24) for introducing a medium different from the pressurized fluid and comprising a filter residue (11, 29), and b) a second inlet (4, 28) for introducing the pressurized fluid; and an inflatable or flexible means (5, 26) contained in the housing (2, 22) and constructed and arranged to be actuated by the pressurised fluid so that, in an inflated or bent state, it presses the filter residue (11, 29) contained in the medium introduced through the first inlet (1, 24) against a filter means (7, 25); where the housing (2, 22) is designed for arrangement in a washing machine; and characterized in that the filter medium (7, 25) is or comprises a filter bag or a filter net and the device (100, 200) further comprises a sieve cup (21) which is arranged in the housing (2, 22) and is designed to receive the filter medium (7, 25).

Description

Field of the invention

[0001] The present invention relates to the field of filter technology and in particular to the treatment of filter residues. Background of the invention

[0002] The filtration of liquids containing suspended particles (unfiltered particles) is important in a wide variety of applications. Contaminants to be removed from the liquids by filtration can include particles of varying sizes, shapes, and compositions, which can quickly clog the filter during the filtration process. One approach to prevent filter clogging is the use of a self-cleaning filter, which regularly removes the residue captured by the filter. The residue can consist of a concentrated suspension of contaminants in a liquid. The treatment of the concentrated suspension is particularly discussed here.

[0003] In connection with, for example, the microfiber filtration of washing wastewater, a filter residue in the form of a (water) sludge with variable density and a typical composition of wastewater, fine particles, in particular microfibers and microplastics, cleaning agents and dirt is discharged from the washing machine filter by cleaning (self-cleaning) of the filter.

[0004] In addition, the water sludge may contain materials such as cotton and other natural fibers that effectively absorb water. These fibers increase in volume and, when agglomerated or layered, form a strong barrier to the water contained in the sludge, preventing passive drainage. To safely dispose of the filtered contaminants, effective, economical, and environmentally sound treatment of the water sludge is required, preferably including controlled dewatering and compaction.

[0005] DE 198 48 064 A1 describes a drum filter press with a filter element designed as a filter cloth and a membrane which separates a solids chamber from a pressurized fluid chamber. In this drum filter press, after the solids chamber has been filled with a suspension to be filtered, the membrane is pressed against the filter element by the pressurized fluid. US 2012 / 0 305 460 A1 describes a device for continuous sludge dewatering and wastewater treatment, in which a mixture of solids and liquid to be filtered can be squeezed out between a cylindrical filter screen and a rubber membrane pressurized with compressed air. EP 3 832 001 A1 describes a household appliance, for example a washing machine, wherein the household appliance has a water line which leads away from a treatment chamber and which also leads to the treatment chamber.The water supply line comprises a plurality of hoses, pipes, branches, and valves, or the like. The household appliance also comprises a detergent container connected to the water supply line. This allows the detergent to flow into the water supply line and thus into the treatment chamber. The detergent container comprises a detergent reservoir and is located inside the household appliance. A filter device is provided to filter particles from the water supply line. These particles are, in particular, plastic fibers and / or microplastics. The water supplied through the water supply line is filtered, so that the filter device is also connected to the water supply line. The household appliance comprises a collecting container for filtrate from the filter device, which is connected to the filter device. The detergent container is firmly connected to a filtrate container, so that both are part of a self-manageable structural unit.

[0006] Against this background, it is an object of the present disclosure to provide techniques for treating filter residues, in particular water sludge that accumulates during a wash cycle in a washing machine. Description of the invention

[0007] The present invention achieves the above-mentioned object by providing a device for treating filter residues, which is particularly capable of partially drying filter residues, compacting them, and, if necessary, providing short- to medium-term storage of the treated residue. Such a device for treating filter residues comprises a housing, a device for supplying a pressurized fluid, and an inflatable or flexible means contained within the housing. The housing is designed for placement in a washing machine.

[0008] The filter medium is a filter bag or a filter net, or comprises a filter bag or a filter net. The device further comprises a sieve cup arranged in the housing and designed to receive the filter medium.

[0009] The housing comprises a first inlet for introducing a medium (unfiltered material) that is different from the pressurized fluid and contains filter residue (resulting from a previous filtration process, in particular the cleaning of a filter device used for a previous filtration process), and a second inlet for introducing the pressurized fluid. The inflatable or flexible means is designed and arranged to be actuated by the pressurized fluid so that, in an inflated or bent state, it presses the filter residue contained in the medium introduced through the first inlet against a filter medium. The actuation by the pressurized fluid can comprise (direct) mechanical contact with the inflatable or flexible means for inflation or bending.The inflatable or flexible means may be or consist of a hose or tube or a membrane or a balloon.

[0010] The filter residue treatment device may also comprise a filter means and also a fastening means for connecting the device to inlet / outlet connections provided for connecting the filter residue treatment device to another device that uses the filter residue treatment device.

[0011] The medium treated by the device can be water sludge, in particular water sludge generated during the cleaning of a washing machine's filter system, e.g., a standard household washing machine. In this case, the filter residue to be treated includes microfibers and microplastics, the entry of which into the environment is to be prevented.

[0012] The filter residue treatment device thus designed enables efficient dewatering (or, where appropriate, removal of other liquids) and compaction of the filter residue contained in the medium entering the filter residue treatment device. The compacted residue can be easily removed from the device and disposed of after the filter residue treatment device's operating life.

[0013] The filter media may be included in the device for treating filter residues. The filter bag may comprise a porous material made of natural or synthetic materials, either organic or inorganic, including paper, fibrous structures, or nonwoven textiles.

[0014] The housing may be made of or comprise a porous material and / or include openings. The extracted liquid, separated from the filter residue (the suspension) by the filter medium and the actuation of the inflatable or flexible means, may exit the housing through the pores and / or openings and be collected for discharge or recycling for further use.

[0015] The pressurized fluid can be a liquid, e.g., water, or a gas, e.g., air. According to one embodiment, the device for supplying the pressurized fluid comprises a fresh water supply, a water pump, or an air pump.

[0016] The above-described examples of the device for treating filter residues according to the invention can be conveniently used for a washing machine or other appliance with a filter from which a filter residue suspension is discharged. In particular, the device for treating filter residues can further comprise a hose or pipe in which the housing is arranged. The purified water exiting the housing can be collected in the hose or pipe and fed (via an outlet located in the hose or pipe) to any destination deemed suitable, for example, a drain pump or a washing machine drum.

[0017] According to the invention, the device for treating filter residues comprises an inflatable or flexible means configured to press the filter residue against the filter medium when inflated or bent. It can also be configured to push the filter medium toward the housing. This allows the inflatable or flexible means to significantly increase the efficiency of drying and compacting the residue.

[0018] By activating the inflatable or flexible device, the filter bag can be pressed against the sieve bowl. The residue is compacted, and water can be forced through openings in the sieve bowl and discharged through an outlet in the housing.

[0019] In another embodiment, in which the device for treating filter residues comprises the filter cup, the housing can be configured to be accommodated in a drawer of a washing machine or in at least part of a drawer of a washing machine. Handling of the device for treating filter residues can be facilitated by accommodating it in a drawer that can be conveniently opened and closed by a washing machine user.

[0020] Furthermore, a washing machine is provided which comprises the device for treating filter residues according to one of the examples described above.

[0021] The above-mentioned objective (providing techniques for treating filter residues) is also achieved by providing a method for treating a filter residue using the device for treating filter residues according to any one of the examples described above, which method comprises the following steps, carried out in the order given: introducing (through the first inlet) an unfiltered material containing the filter residue into the housing, filtering the unfiltered material through the filtering means to collect the filter residue on the filtering means, and inflating or bending the inflatable or flexible means (by the pressurized fluid introduced through the second inlet) to press the collected filter residue against the filtering means to compact the collected filter residue.The filter residue results from a previously performed filtration process through a different filter device than the filter medium contained in the device for treating filter residues. Therefore, the method further comprises filtering another unfiltered product through another filter device / filter medium (which, in particular, is not part of the device for treating filter residues) and cleaning the other filter device / filter medium to obtain the unfiltered product containing the filter residue.

[0022] According to one embodiment, the method comprises repeating the steps of introducing unfiltered material, filtering the unfiltered material, and inflating or bending the inflatable or flexible medium until a capacity of the filter medium (e.g., the filling capacity of a filter bag) is reached, and then removing filter residues accumulated in or on the filter medium from the filter residue treatment device. In this way, the filter medium can be used for multiple cycles of filtering unfiltered material and compacting filter residues before being cleaned or disposed of, for example.

[0023] The method according to the examples described above can be carried out in a washing machine and the other filter device can be a conventional self-cleaning filter of the washing machine.

[0024] Further features and advantages of the present invention will be described with reference to the drawings. In the description, reference is made to the accompanying figures, which are intended to illustrate exemplary embodiments of the invention. It should be understood that such embodiments do not represent the full scope of the invention. Fig. 1 is an isometric view schematically showing a filter residue treatment apparatus having a housing disposed in a hose or tube according to an example not forming part of the present invention. The Fig. 2 and Fig. 3 are sectional views showing the Fig. 1 show the device for treating filter residues in different operating conditions. Fig. 4 is an exploded view of a filter residue treatment apparatus according to an embodiment of the present invention, including a strainer cup. The Fig. 5 and Fig. 6 are sectional views showing the Fig. 4 show the device for treating filter residues in different operating conditions.

[0025] The present invention provides a filter residue treatment device for compacting a filter residue. The filter residue results from a filtering process applied to a previous unfiltered material and is fed to the filter residue treatment device in a liquid, e.g., water, for further processing. The liquid containing the filter residue itself represents an unfiltered material to be treated by the filter residue treatment device.

[0026] The invention is particularly suitable for treating filter residues that accumulate on a (self-cleaning) filter device in a washing machine. For example, during a self-cleaning process of the filter device, the filter residue is washed out, and the resulting sludge can be treated with the device for treating filter residues according to the invention.

[0027] Fig. 1 shows a device 100 for treating filter residues according to an example not forming part of the present invention, wherein the device 100 is usable for a washing machine, in particular a conventional household washing machine. The device 100 for treating filter residues comprises a housing 2 with an inlet 1 through which water sludge can be introduced into the housing 2. The water sludge can be introduced into the housing 2, for example, by means of a pump. The housing 2 can be arranged in a tubular geometric shape and can be a pipe or hose 10. Within the housing 2, the water sludge is treated such that the filter residue contained in the water sludge is compacted.The housing 2 includes openings or pores, and the draining water leaving the housing 2 through the openings or pores is collected in the pipe or hose 10 and can exit the filter residue treatment device 100 through an outlet 3 located in the pipe or hose 10. The clean water leaving the filter residue treatment device 100 through the outlet 3 can, for example, be fed to a drain pump or returned to a washing machine drum.

[0028] The Fig. 2 and Fig. 3 show further details of the Fig. 1 in a first operating state or a second operating state following the first. The water sludge is introduced into the housing 2 through the inlet 1 and enters a filter bag 7 provided in the housing 2, which is held by a filter bag holder 6. The filter bag 7 can be made, for example, of a woven fabric or nonwoven fabric. The water sludge is filtered through the filter bag 7, and the filtered water leaves the housing 2 through the openings or pores of the housing, is collected in the pipe or hose, and leaves the device 100 for treating filter residues through the outlet 3. Meanwhile, the filter residue contained in the introduced water sludge is collected in the filter bag 7 in the first operating state.

[0029] Furthermore, the device 100 for treating filter residues comprises an inflatable means 5 connected to a pressure inlet 4 for introducing a pressurized fluid. The inflatable means 5 may be or comprise a hose or tube or a balloon (balloon-like insert) or another suitable form of a flexible membrane. In the second operating state, the inflatable means 5 is inflated by a pressurized fluid introduced through the pressure inlet 4 (see Fig. 3). The pressurized fluid may be pressurized water supplied from a fresh water supply of the washing machine. Alternatively or additionally, a water pump or an air pump may be provided to direct the pressurized fluid into the filter residue treatment device 100 to inflate the inflatable means 5.

[0030] As the inflatable means 5 inflates, it reduces the available volume within the housing 2 and thus pushes the water content of the remaining sludge through the filter material of the filter bag 7. By pressing the residue 11 against the filter bag 7, the residue 11 (mainly microfibers and microplastics filtered out by a self-cleaning filter device of the washing machine) is simultaneously dewatered and compacted. The pressurized inflatable means 5 fills the entire available space and presses against both the filter bag 7 and the housing 2. This displaces (almost) all of the water from the filter bag 7 and the housing 2 through the openings or pores provided therein. Since the water has to flow through the forming deposit cake and the filter bag, it is clean, i.e. it does not contain any solid residue 11, and can, for example,be returned to the washing machine drum for further use.

[0031] After a few operating cycles, the capacity of the filter bag 7 is reached. The residue can be removed by unscrewing the housing 2 from the washing machine using a handle 8 and removing the filter bag 7. The filter bag can then be replaced with an empty filter bag if it is disposable, or alternatively, it can be cleaned and reinserted for further use. Since the solid residue 11 is compacted by the expanding inflatable means 5, the amount of residue 11 stored in the available volume of the filter bag 7 can be maximized. The interval between removing filter bags 7 containing compacted residue is therefore maximized and user intervention is minimized.

[0032] In the example described above, the inflatable means 5 can be replaced by a flexible means, for example a membrane, which is bent against the filter bag 7 by the pressurized liquid in order to press the filter residue against the filter bag 7 and the housing 2 of the filter residue treatment device 100.

[0033] An embodiment of a device 200 according to the invention for treating filter residues is shown in the Fig. 4, Fig. 5 and Fig. 6. The device 200 for treating filter residues according to this embodiment is suitable for being accommodated in a drawer of a washing machine, for example, a conventional household washing machine. This drawer can, for example, be provided separately from a conventional detergent drawer or attached to it. This embodiment serves to illustrate one possible embodiment of the invention but in no way excludes other applications and modalities.

[0034] The Fig. 4, Fig. 5 and Fig. The device 200 for treating filter residues shown in Figure 6 comprises a sieve cup 21 with openings. The sieve cup 21 can be accommodated in a housing 22. The housing 22 can be designed such that it can be inserted into a drawer of a washing machine, or it can represent a drawer or part of a drawer of a washing machine. The housing 22 comprises an outlet 23 for the outflow of the drained water and an inlet 24 for the introduction of water sludge and can otherwise be solid without pores or further openings. A filter bag 25 (e.g. made of a woven fabric, nonwoven fabric or a durable plastic fabric) can be accommodated in the sieve cup 21.The strainer cup 21, together with the filter bag 25, which stores the compacted filter residue introduced with a water sludge supplied to the device 200 for treating filter residues, can be removed from the housing 22 (after reaching the capacity of the filter bag 25) and inserted into the housing (at the beginning of an operating cycle). In an operating position, a neck 25a of the filter bag 25 is connected to a counter-receptacle 21a provided in the strainer cup 21 and the inlet 24 of the housing 22, so that incoming water sludge is directly received by the filter bag 25.

[0035] Furthermore, the device 200 for treating filter residues comprises a flexible means 26, e.g., a flexible membrane, arranged under a cover 27. The cover 27 may, for example, be a cover or part of a cover provided for a drawer of a washing machine, or it may be a separate cover. In any case, the cover 27 comprises a pressure inlet 28 for introducing a pressurized fluid.

[0036] The Fig. 5 and Fig. 6 show cross-sectional views of the device 200 for treating filter residues in a first operating state and in a second operating state following the first operating state, respectively. In the first operating state, a water sludge resulting from the cleaning of a filter device in the washing machine flows through the inlet 24 of the housing 22 into the interior of the device 200 for treating filter residues, and the solid, particulate filter residue contained in the water sludge is collected in the filter bag 25, while the water is drawn off through the filter bag 25 and the strainer cup 21 and flows back into the washing machine drum through the outlet 23. In the first operating state, the filter bag 25 is filled with the water sludge and therefore occupies the entire available volume of the strainer cup 21 (see Fig. 5).

[0037] In the second in Fig. 6, the residue 29 is further dewatered and compacted, and the remaining water content is drawn out of the filter bag 25 by actuating the flexible means 26. The flexible means 26 may be a membrane and is bent / actuated either by pressurized water from the fresh water supply already available in the washing machine or by water or air from a water or air pump that can generate sufficient pressure to draw the water out of the residue 29. In both cases, the pressurized fluid is supplied through the pressure inlet 28 of the cover 27. As the flexible means 26 is bent, it presses downwards (as indicated by the arrows in Fig. 6), thereby reducing the available volume of the filter bag 25, and it pushes the water content of the water residue through the filter bag 25 and out of the housing 22 of the filter residue treatment device 200 through the outlet 23.

[0038] By pressing the residue 29 against the wall of the filter bag 25 and toward the strainer cup 21, the residue 29 is simultaneously dewatered and compacted. When the filter bag 25 is full, the user pulls out the drawer or drawer-like movable subassembly of the strainer cup 21 along with the filter bag 25 housed therein, removes the filter bag 25 from the strainer cup 21, and either cleans it (in the case of a reusable type) or replaces it with a new one if it is designed as a consumable, replaceable part. In the latter case, the user does not need to handle the solid waste currently collected in the filter bag 25, and the filter bag replacement can be kept clean and simple.

[0039] A new or cleaned filter bag can be reinserted simply by inserting the bag neck of a new filter bag or the bag neck 25 of the cleaned filter bag 25 into the corresponding receptacle 21a provided in the strainer cup 21. The drawer subassembly could be part of an existing detergent drawer (as a standard part of a washing machine), arranged either parallel to or at the rear of the existing detergent drawer, or it could be part of an additional drawer dedicated exclusively to the housing and operation of the filter residue treatment device 200.

[0040] In the above-mentioned with reference to the Fig. 4, Fig. 5 and Fig.6, the flexible means 26 may be replaced by an inflatable means, such as a hose or tube or balloon, which is inflated by the pressurized fluid to press against the filter bag 25 and towards the strainer cup 21.

[0041] All previously described embodiments are not to be understood as limitations, but rather serve as examples to illustrate the features and advantages of the invention. It is understood that some or all of the features described above may also be combined in different ways.

Claims

[1] Device (100, 200) for treating filter residues, comprising a device for supplying a pressurized fluid; a housing (2, 22) having a) a first inlet (1, 24) for introducing a medium different from the pressurized fluid and comprising a filter residue (11, 29), and b) a second inlet (4, 28) for introducing the pressurized fluid; and an inflatable or flexible means (5, 26) contained in the housing (2, 22) and constructed and arranged to be actuated by the pressurised fluid so that, in an inflated or bent state, it presses the filter residue (11, 29) contained in the medium introduced through the first inlet (1, 24) against a filter means (7, 25); where the housing (2, 22) is designed for arrangement in a washing machine; and characterized by , that the filter medium (7, 25) is or comprises a filter bag or a filter net and the device (100, 200) further comprises a sieve cup (21) which is arranged in the housing (2, 22) and is designed to receive the filter medium (7, 25). [2] The device (100, 200) for treating filter residues according to claim 1, wherein the inflatable or flexible means (5, 26) is or comprises a flexible and elastic hose or a flexible and elastic tube, or a balloon or a membrane. [3] The device (100, 200) for treating filter residues according to any one of the preceding claims, further comprising the filter means (7, 25). [4] The device (100, 200) for treating filter residues according to one of the preceding claims, wherein the housing (2, 22) comprises openings and / or is made of a porous material. [5] The device (100, 200) for treating filter residues according to any one of the preceding claims, wherein the means for supplying the pressurized fluid comprises a fresh water supply, a water pump or an air pump. [6] The device (100, 200) for treating filter residues according to any one of the preceding claims, further comprising a hose or pipe (10) comprising an outlet (3), and wherein the housing (2, 22) is arranged in the hose or pipe (10). [7] The device (100, 200) for treating filter residues according to any one of the preceding claims, wherein the inflatable or flexible means (5, 26) is designed to press the filter means (7, 25) against the housing (2, 22). [8] The device (100, 200) for treating filter residues according to claim 1, wherein the housing (2, 22) is designed to be accommodated in a drawer of a washing machine or is at least part of a drawer of a washing machine. [9] The device (100, 200) for treating filter residues according to claim 1 or 8, wherein the inflatable or flexible means (5, 26) is designed to press the filter means (7, 25) against the sieve cup (21). [10] Washing machine with the device (100, 200) for treating filter residues according to one of the preceding claims. [11] Method for treating a filter residue (11, 29) using the device (100, 200) for treating filter residues according to one of claims 1 to 9, comprising the following steps carried out in the specified order: Introducing an unfiltered material comprising the filter residue (11, 29) into the housing (2, 22); filtering the unfiltered material through the filter medium (7, 25) which is different from the filter device in order to collect the filter residue (11, 29) on the filter medium (7, 25); Inflating or bending the inflatable or flexible means (5, 26) to press the collected filter residue (11, 29) against the filter means (7, 25) to compact the collected filter residue (11, 29); and Filtering another unfiltered product through a filter device different from the filter medium (7, 25) and cleaning the other filter device to obtain the unfiltered product comprising the filter residue (11, 29). [12] The method of claim 11, wherein the steps of introducing an unfiltered material, filtering the unfiltered material and inflating or bending the inflatable or flexible means are repeated until a capacity of the filtering means is reached, and subsequently removing the filter residue accumulated in or on the filtering means from the device (100, 200) for treating filter residues.

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