CZ26795U1 - Filter and liquid purification device - Google Patents

Description

Filter and equipment for cleaning liquids

Technical field

The invention relates to a liquid purification filter comprising a frame and at least one filter wall, wherein the filter walls together with the frame define an enclosed interior space connectable to a fluid discharge conduit from the interior of the filter. The invention also relates to a liquid purification device comprising such a filter.

BACKGROUND OF THE INVENTION

Filters of the above type are mainly used in waste water treatment plants, for example for surface and rain water treatment plants, domestic waste water treatment plants, gray water treatment plants, etc.

In such devices, the filter is submerged in the tank with purified water and inside it filters the inlet of the pump line provided with the pump. The pump generates a vacuum inside the filter so that the purified water is sucked through filter walls, usually perforated plates or membranes, into the interior of the filter, thereby purifying the water and draining it from the tank through (e.g. domestic water). After a period of operation of the device, the holes in the filter wall will clog and usually need to be mechanically flushed with a backflow.

A disadvantage of filters whose filter walls are formed by a perforated plate or membrane or a similar sheet material with very small holes is that the ratio of the area formed by the holes to the full area is relatively small and as a result the holes are often clogged and therefore often by flushing and, on the other hand, a relatively high vacuum must be used when filtering, i.e., sucking liquid out of the filter interior.

The essence of the technical solution

The aforementioned disadvantages are eliminated by a liquid cleaning filter comprising a frame and at least one filter wall which together with the frame defines an enclosed interior connectable to the discharge line, the filter wall comprising at least one support layer of woven or nonwoven fabric to which it is attached layer of polymer nanofibres.

The filter wall may further include a support grid to reduce or prevent deformation of the filter wall under vacuum in the interior of the filter. Preferably, the layer of nanofibres is formed from nanofibres with a diameter of 1 to 1000, especially 40 to 920 nm, most preferably of nanofibres selected from the group of polyurethane, polyamide, polyvinylidene fluoride, polyethersulfone, polysulfone, polystyrene, polyacrylonitrile, polycarbonate, polymethyl methacrylate, polylactide fibers, or combinations thereof.

Preferably, the carrier layer and the nanofiber layer are interconnected by hot melt adhesive micro-drops and / or bonding points or lines formed by melting at least some parts (some fibers) of the filter wall material during calendering or pressing.

The above drawbacks are also eliminated by a liquid cleaning device which includes:

- tank,

a drain line for draining liquid from the tank, and

a filter as described above, wherein the inlet orifice of the discharge line is connected to or arranged in the interior of the filter.

Preferably, the apparatus further comprises a pump to which a drain line is connected for pumping liquid from the interior of the filter. In another preferred embodiment, the device further comprises

-1 CZ 26795 Ul

- a reservoir,

- flushing piping,

- a three-way valve arranged in the manifold and adapted to switch the interconnection of the interior of the filter to the storage tank via a pump or a flushing line,

a pressure sensor arranged in the manifold between its inlet and the pump, and a control unit connected to the pressure sensor and the three-way valve to control the three-way valve based on the pressure values detected by the pressure sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention are schematically illustrated in the figures, wherein Fig. 1 is a first embodiment of a liquid cleaning apparatus according to the present invention and Fig. 2 is a second embodiment, Fig. 3 is a third embodiment and Fig. 4 is a fourth embodiment.

Description of exemplary embodiments

The first embodiment shown in FIG. 1 comprises a tank 1 in which an exemplary embodiment of filter 2 is arranged. The illustrated filter 2 comprises a frame 21 to which two filter walls 22 are spaced apart. The frame 21 together with the filter walls 22 define an enclosed space into which the outlet pipe 3 is located at its inlet opening. The outlet pipe 3 is led out of the tank 1. To create a vacuum inside the filter 2, in this embodiment it is utilized that the level in tank 1 is above the outlet port 3.

During the cleaning of the liquid, due to the above-mentioned negative pressure, the liquid from the tank 1 is sucked through the filter walls 22 into the inner space of the filter 2, while impurities are trapped on the outside of the filter walls 22. The purified liquid is drained from the inner space of the filter 2 for further use.

The filter walls 22 comprise a support layer on which a layer of nanofibres is applied, preferably fibers with a diameter of 30 to 1000 nm, preferably 40 to 920 nm. Advantageously, the filter walls 22 may additionally comprise a support grid which prevents the filter walls 22 from being deformed by pressure. The backing layer may consist of one or more layers of woven or nonwoven fabric of synthetic or natural or glass fibers, for example, a polyester fabric or polypropylene nonwoven fabric is particularly preferred. In general, the backing layer may be a polyester, polyamide, polylactide or cotton fabric, a non-woven fabric of polypropylene, polyester, viscose, cellulose, polylactide or glass fibers, or a combination of at least two of the above materials.

The layer of nanofibres can also be formed as one or multilayer and prepared from fibers of polyurethane, polyamide, polyvinylidene fluoride, polyether sulfone, polysulfone, polystyrene, polyacrylonitrile, polycarbonate, polymethylmethacrylate, ethylene vinyl acetate, copolymers of the above, copolyester, copolyamide, copolyamide, copolyamide, copolyamide, copolyamide, copolyamide. The pore size in the nanofiber layer is preferably 200 to 500 nm (measured according to ASTM F3 16-03). The support grid can be made, for example, of a fabric, aluminum, plastic or stainless steel or a porous ceramic material.

A suitable material for the filter walls 22 is, for example, SpurTex MF manufactured by SPUR as Zlín.

The bonding of the carrier layer to the nanofiber layer can be realized, for example, by applying micro-droplets of hot-melt adhesive, and / or by calendering or pressing to form binding lines or dots formed from the fusible parts of the multilayer filter wall material.

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The filter wall 22 has a large number of through holes of very small dimensions due to the above laminated construction, and the ratio of the area of the openings to the total area of the filter wall 22 is significantly higher than that of conventional perforated filter walls while maintaining sufficient ability to separate very fine particles. It has been found that using the filter 2 of the present invention in a liquid cleaning device requires less vacuum to evacuate the cleaned liquid and less frequent cleaning the filter 2 than using conventional perforated filter walls.

In this case, the filter walls 22 are in the form of rectangular plates clamped into the respective rectangular frame 21. Other embodiments are possible, for example it is possible to form tubular filter walls of circular or oval cross-section, the frame having a corresponding construction, e.g. circles, which form the upper and lower base of the filter wall tube, and wherein one of the circles is provided with a sleeve for fastening the discharge pipe.

The apparatus further comprises an aeration element 4 arranged in the tank I below the filter 2. The aeration element 4 bubbles liquid in the tank 1 and air bubbles remove impurities from the outside of the filter walls 22. The aeration element 4 reduces clogging of the filter 2 and that the filtration is carried out in activated sludge or in a heavily contaminated liquid.

A second exemplary embodiment of the liquid cleaning device is shown in Fig. 2 and differs from the first exemplary embodiment in that it additionally comprises a pump 5, wherein the discharge line 3 is connected to the pump 5 to generate a vacuum in the interior of the filter 2, i.e. cleaned liquid from the interior of the filter 2 and draining it to the point of use.

A third exemplary embodiment of the liquid cleaning device is shown in Fig. 3 and differs from the second exemplary embodiment in that it additionally comprises a reservoir 6 into which a drain pipe 3 is connected via a pump 5. . If the filter walls 22 become clogged, the pump 5 can be switched off and the liquid collected in the reservoir 6 is allowed to flow back into the interior of the filter 2 so that it is backwashed and thus cleaned. Then the pump 5 is switched on again and the filtration and the removal of the purified liquid through the discharge line 3 can continue again.

A fourth exemplary embodiment of the liquid cleaning device is shown in Fig. 4 and differs from the third exemplary embodiment in that it additionally comprises a three way valve 7, a control unit 8, a pressure sensor 9 and a flushing line 10. The discharge line 3 is routed through a three-way the valve 7 and the pump 5 into the reservoir 6 and from there to the point of further use of the purified liquid. A pressure sensor 9 is arranged in the discharge line 3 between the three-way valve 7 and the pump 5, whereby the three-way valve 7 and the pressure sensor 9 are connected to the control unit 8. The flushing line 10 connects the three-way valve 7 to the reservoir 6.

During operation of the device, the pump 5 draws the cleaned liquid out of the interior of the filter 2, also through the discharge line 3 through the three-way valve 7 and the pump 5 to the storage tank 6 and after filling it further through the line for further use. The pressure in the discharge pipe 3 is continuously sensed and the values are transmitted to the control unit 8. Increasing the pressure in the outlet pipe 3 above the set limit indicates that the filter 2 is clogged. in which the flushing line 10 is connected to the bottom of the drain line 3 so that the liquid from the reservoir 6 flows by gravity into the interior of the filter 2 and flushes it. Thereafter, the three-way valve 7 returns to its original position and the pump 5 begins to drain the liquid from the interior of the filter 2 to the reservoir 6 and after filling the purified liquid is discharged for further use.

Exemplary embodiments of the invention have been described, and other possible variants will also be apparent to those skilled in the art and are also within the scope of the claims.

Claims (7)

PROTECTION REQUIREMENTS A liquid purifying filter (2) comprising a frame (21) and at least one filter wall (22) which, together with the frame (21), defines an enclosed interior connectable to a drain line (3), characterized in that the wall (22) comprises at least one supporting layer of woven or non-woven fabric to which a layer of synthetic nanofibres is attached. Filter (2) according to claim 1, characterized in that the filter wall (22) further comprises a support grid to reduce or prevent deformation of the filter wall (22) under negative pressure in the interior of the filter (2). Filter (2) according to claim 1 or 2, characterized in that the layer of nanofibres is made of nanofibres with a diameter of 1 to 1000 nm, preferably 40 to 920 nm, preferably of nanofibres selected from the group of polyurethane, polyamide, polyvinylidene fluoride, polyethersulfone , polysulfone, polystyrene, polyacrylonitrile, polycarbonate, polymethyl methacrylate, ethylene vinyl acetate, copolyester, copolyamide and polylactide fibers, or combinations thereof. Filter (2) according to any one of the preceding claims, characterized in that the carrier layer and the nanofiber layer are interconnected by micro-drops of hot-melt adhesive and / or bonding points or lines formed by melting at least some parts of the filter wall material (22). pressing. 5. Liquid purification equipment, comprising: - tank (1), a drain line (3) for draining the liquid from the tank (1), and - filter (2) according to any one of the preceding claims, wherein the inlet mouth of the discharge pipe (3) is connected to or arranged in the interior of the filter. Apparatus according to claim 5, further comprising a pump (5) to which a drain line (3) is connected to draw liquid from the interior of the filter (2). The apparatus of claim 6, further comprising - a reservoir (6), - flushing pipe (10), - a three-way valve (7), which is arranged in the discharge line (3) and adapted to switch the connection between the interior of the filter (2) and the storage tank (6) via the pump (5) or through the flushing line (10), - a pressure sensor (9) arranged in the discharge pipe (3) between its inlet and the pump (5), and - a control unit (8) connected to the pressure sensor (9) and the three-way valve (7) for controlling the three-way valve based on the pressure values detected by the pressure sensor (9).