Liquid filtering system

Abstract

The invention relates to a liquid filtering system, which comprises a fibreglass-reinforced polyester tank (10); an upper plate (20) provided with a plurality of holes for the coupling of hoses (40); a plurality of hoses (40) arranged in a lower compartment and which comprise an outer surface forming a support for a filtering medium, an inner surface defining a conduit for circulating the filtered liquid to an upper compartment (102), a closed bottom end (401) and an open top end (402) coupled to a corresponding hole in the upper plate (20); a control panel; a water supplying tube (106) for supplying water for the periodic cleaning of the filter; and a pressurised-air supply tube (105) for supplying pressurised air for the regeneration of the filtering medium.

Description

[0001]DESCRIPTION A liquid filtration system. Technical field. The present invention relates to a liquid filtration system comprising a filtration tank with a lower inlet for the liquid to be filtered, an upper outlet for the filtered liquid, and inside, an upper support plate for a series of flexible hoses whose outer surface forms a support for a filter medium, for example, perlite or similar. This filtration system is applicable in the sector dedicated to the purification of liquids with a low or medium contaminant load and primarily for large flows of water from swimming pools, lagoons, ponds, or similar sources. Prior art.Currently, different types of liquid filters are known in the state of the art, among which we can distinguish: water filters with a glass fiber reinforced polyester container and a filtration surface corresponding to its useful area or section, steel filters with a regenerative perlite filter medium, and glass fiber reinforced polyester (GFRP) filters with a regenerative perlite filter medium such as those described in patent applications WO2018211161A1 and WO2022101528A1, of the same holder of the present invention.Document WO2022101528A1, considered the closest to the present invention, describes a liquid filtration system comprising a filtration tank provided with a roof or separator plate that divides the interior thereof into a lower compartment and an upper compartment; an inlet conduit for the liquid to be filtered towards an area near the lower wall of said tank; a plurality of hoses that protrude from the roof or separator plate towards the lower compartment; said hoses comprising an outer surface that forms a support for a filter medium and an inner surface that defines a circulation conduit for the filtered liquid, closed at the lower end and open at the upper end, towards the upper compartment; an outlet conduit for the filtered water through the upper area of ​​the tank; a regeneration circuit for the filter medium; a self-cleaning circuit for the filter; and a control panel.The liquid filtration system described in WO2022101528A1 incorporates features designed to improve the performance of the filtration system described in the previous document WO2018211161A1, specifically to prevent the uncontrolled and forceful entry of the liquid to be filtered from the inlet into the hoses. This uncontrolled entry can cause the perlite filter material to detach from the outer surface of the hoses, thereby negating or excessively reducing the system's filtration capacity. To achieve this, the filtration system described in WO2022101528A1 incorporates a liquid distribution plate, positioned horizontally between the inlet pipe and the lower end of the hoses. This plate comprises a plurality of perforations for the passage and distribution of the liquid to be filtered into the hoses.During the use of this filtration system, the inventor detected some problems related to filter cleaning and filter media regeneration. The first problem is the accumulation of grease and viscous materials at the upper end of the lower compartment. In the case of pool water filtration, these materials consist mainly of grease and sunscreens, moisturizers, or similar substances. During operation, this grease accumulates by floating beneath the upper plate and between the flexible hoses. When a significant flow of pressurized air is introduced into the tank to regenerate the filter media, the rising air forces the filter media against the upper plate, forming a crust with the grease that clogs the upper portion of the flexible hoses.Under these conditions, the air introduced into the lower compartment during filter media regeneration accumulates in the upper part of that compartment, creating overpressure that forces water through the lower part of the flexible hoses into the upper compartment and then out of the tank. This causes a significant portion of the water in the tank to be unnecessarily expelled during filter media regeneration. This water loss lowers the water level in the lower compartment, preventing the water from reaching and removing the scale that has accumulated under the upper plate and between the upper part of the flexible hoses, resulting in inadequate cleaning.A second problem detected is that during the regeneration of the filter medium, the filter medium is released from the hoses and accumulates in specific areas that are protected from the upward currents of liquid and air, specifically in a peripheral area of ​​the lower plate near the side wall of the tank and on shelves defined by the manholes located on the side wall of the tank, so a complete regeneration of the filter material is not achieved either.Therefore, the technical problem posed is the development of a liquid filtration system of the type described above, which minimizes the amount of water unintentionally discarded during filter media regeneration; which achieves effective cleaning of the filtration system, preventing dirt residue from adhering to the underside of the upper plate and between the hoses; and which performs complete regeneration of the filter media. Explanation of the invention. The liquid filtration system of this invention, being of the type described in document WO2022101528A1 and in the preamble of the main claim of the invention, has technical characteristics that resolve the problems outlined above.One of the features of the invention is that the filtration system comprises an exhaust tube for the pressurized air supplied for the regeneration of the filter medium. This exhaust tube includes an inlet located in the upper part of the lower compartment of the tank, near the upper plate, and an outlet for air to the outside of the tank. The air outlet through this exhaust tube ensures that the flow of pressurized air introduced into the tank during the regeneration of the filter medium can rise through the lower compartment and exit to the outside. During this upward movement, the water contained in the lower compartment is mobilized, removing all dirt, including the grease and filter medium buildup on the lower surface of the upper plate.Another advantage of this drain tube is that the pressurized air introduced into the tank for filter media regeneration does not generate enough pressure in the lower compartment to displace the water through the hoses to the upper compartment and unnecessarily expel it. Therefore, during the regeneration phase, the amount of water discarded is very small, and most of it remains in the lower compartment, effectively cleaning the upper part of the lower compartment and removing the scale accumulated beneath the upper plate. The liquid filtration system of this invention has other additional features that contribute to the complete regeneration of the filter media and prevent any perlite or filter media from accumulating in areas sheltered from the upward air and water currents.To this end, and in accordance with the invention, the liquid distribution plate comprises a series of recesses around its perimeter which, together with the side wall of the tank, define passageways for the filter medium released from the hoses during regeneration to flow to the lower area. To prevent the accumulation of perlite or filter medium in the manhole, said manhole comprises a tubular body mounted in a substantially horizontal position within a defined opening in the side wall of the tank and extending into the tank body. This tubular body includes a cap mounted on the end of the tubular body housed in the tank, preventing the perlite or filter medium from entering and becoming trapped inside the tubular body of the manhole. The manhole is provided with a sight glass screwed into the cap, allowing visual inspection of the tank's interior.Brief description of the content of the drawings. To complement the description provided and to facilitate understanding of the invention's features, a set of drawings is included with this specification. These drawings, for illustrative purposes only and not intended to be limiting, depict the following: - Figure 1 shows a schematic elevation view of an example of the liquid filtration system according to the invention, sectioned by a vertical plane. - Figure 2 shows a horizontal section of the filtration system in the previous figure, sectioned by a horizontal plane. This section illustrates the plan view of the liquid distribution plate and the recesses defined in its contour for the passage of the perlite or filter medium to the lower zone during regeneration or cleaning.Figure 3 shows an enlarged detail of a side portion of Figure 1, in which the manhole section with the sight glass-bearing cover can be seen, arranged at the end of the tubular body housed inside the tank. Detailed exposition of embodiments of the invention. In the embodiment shown in Figure 1, the liquid filtration system comprises a fiberglass-reinforced polyester tank (10), which includes an upper plate (20) provided with a plurality of holes for coupling the hoses (40) and which divides the interior of said tank (10) into a lower compartment (101) provided with an inlet (103) for the liquid to be filtered, and an upper compartment (102) provided with an outlet (104) for the filtered liquid.The filtration system comprises a liquid distribution plate (30), horizontally arranged in the lower compartment (101), between the cleaning water supply pipe (106) and the pressurized air supply pipe (105) for filter media regeneration. The plate has a plurality of openings (301) through which the liquid to be filtered flows to a multitude of hoses (40). These hoses have an outer surface that supports a filter media (not shown) and an inner surface that defines a conduit for the upward flow of the filtered liquid. The hoses (40) have a closed lower end (401) and an open upper end (402) coupled to the corresponding opening in the upper plate (20), through which the filtered liquid flows to the upper compartment (102).The lower compartment (101) has a water supply pipe (106) for periodic filter cleaning; a pressurized air supply pipe (105) for filter media regeneration; and a drain port (110). The tank (10) comprises, in the lower compartment (101), a connection port (108) for a hose for loading the perlite or filter media, and in the upper compartment (102), a connection port (109) for a suction device that facilitates loading the perlite, an aeration valve (107), and a level sensor (111). The operation of the filtration system is conventionally controlled by a control panel (not shown) that manages the filter cleaning and perlite filter media regeneration cycles.According to the invention, this system comprises an air evacuation tube (50) with an inlet (501) located in the lower compartment (101) near the upper plate (20), and an outlet (502) to the outside of the tank (10). As mentioned, the function of this evacuation tube (50) is to allow the air introduced into the lower compartment (101) by the pressurized air supply tube (105) during filter media regeneration to escape. This air evacuation tube (50) allows the air introduced during filter media regeneration to move the water against the lower surface of the upper plate (20), cleaning the scale accumulated in that area, and then allows the air to escape.Therefore, the aforementioned drain tube (50) prevents the pressurized air introduced into the lower compartment during filter media regeneration from accumulating in the upper area of ​​the lower compartment, which is obstructed by the grease and perlite buildup. This accumulation would generate overpressure capable of forcing water into the hoses at their lower ends, displacing it into the upper compartment, and then outwards. This results in a significant water loss and a drop in the water level in the lower compartment (101), preventing the water from effectively removing the accumulated scale beneath the upper plate (20). During regeneration, the perlite filter media detaches from the hoses (40) and falls to the bottom of the tank (10).As can be seen in Figure 2, to achieve complete regeneration of the filter media, the liquid distribution plate (30) includes a series of recesses (302) around its perimeter. These recesses, together with the side wall of the tank (10), form passageways to the lower part of the tank for the filter media released from the hoses during regeneration or cleaning. As can be seen in Figures 1 and 3, the tank (10) includes, as is customary, a manhole (60) for inspecting the interior of the tank.In this invention, the manhole (60) comprises a tubular body (601) mounted in a substantially horizontal position within a defined opening in the side wall of the tank (10) and extending into the tank body (10). A distinctive feature of this invention is the inclusion of a closing cap (602) mounted on one end of the tubular body (601) located inside the tank. This cap prevents the perlite or filter medium from entering and becoming trapped inside the manhole. The manhole (60) is provided with a sight glass (603) screwed onto the closing cap (602), allowing visual inspection of the tank's interior.Once the nature of the invention has been sufficiently described, as well as an example of a preferred embodiment, it is noted for the appropriate purposes that the materials, shape, size and arrangement of the elements described may be modified, provided that this does not imply an alteration of the essential characteristics of the invention claimed below.

Claims

CLAIMS 1. A liquid filtration system, comprising: - a glass fiber reinforced polyester tank (10); - a top plate (20) provided with a plurality of holes for coupling hoses (40) and dividing the interior of the tank (10) into a lower compartment (101) provided with an inlet (103) for the liquid to be filtered and an upper compartment (102) provided with an outlet (104) for the filtered liquid; - a plurality of hoses (40) arranged in the lower compartment, comprising: an outer surface forming a support for a filter medium, an inner surface defining a conduit for the circulation of the filtered liquid to the upper compartment (102), a closed lower end (401) and an open upper end (402) coupled to the corresponding hole in the top plate (20).- a control panel; - a water supply tube (106) for periodic filter cleaning and a pressurized air supply tube (105) for filter medium regeneration, arranged in the lower compartment (101) of the tank (10), and - a liquid distribution plate (30), provided with a plurality of liquid passage holes (301), arranged horizontally in the lower compartment (101), between the water supply tube (106) for cleaning and the pressurized air supply tube (105) for filter medium regeneration; characterized in that it comprises an evacuation tube (50) for the air supplied by the pressurized air supply tube (105) during the regeneration of the filter medium, said evacuation tube (50) comprising an air inlet (501) arranged in an area of ​​the lower compartment (101) close to the upper plate (20), and an air outlet (502) to the outside of the tank (10). 2.The liquid filtration system according to claim 1, wherein the liquid distribution plate (30) comprises a series of recesses (302) around its perimeter that define passageways to the lower area of ​​the tank (10) for the filter medium released from the hoses (40) during regeneration or cleaning.

3. The liquid filtration system according to any preceding claim, wherein the tank (10) comprises a manhole (60) provided with a tubular body (601). mounted in a substantially horizontal position in a defined opening in the side wall of the tank (10) and extending into the body (10) of the tank; and a closing cap (602) mounted on one end of the tubular body (601) disposed inside the tank.

4. The liquid filtration system according to claim 3, wherein the manhole (60) is provided with a sight glass (603) screwed onto the closing cap (602).

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