WO2021014259A1 - Gravity filter filtering device for softening and purifying driniking water - Google Patents

Gravity filter filtering device for softening and purifying driniking water Download PDF

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Publication number
WO2021014259A1
WO2021014259A1 PCT/IB2020/056449 IB2020056449W WO2021014259A1 WO 2021014259 A1 WO2021014259 A1 WO 2021014259A1 IB 2020056449 W IB2020056449 W IB 2020056449W WO 2021014259 A1 WO2021014259 A1 WO 2021014259A1
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WO
WIPO (PCT)
Prior art keywords
filter element
filtering module
block material
filter
porous block
Prior art date
Application number
PCT/IB2020/056449
Other languages
French (fr)
Inventor
Alexander MASLYUKOV
Viktor SAPRYKIN
Vladimir MASLYUKOV
Anna BREKHOVA
Roman PODOBEDOV
Juergen Johann
Original Assignee
Bwt Barrier Rus Jsc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bwt Barrier Rus Jsc filed Critical Bwt Barrier Rus Jsc
Priority to EP20746705.1A priority Critical patent/EP4003918A1/en
Publication of WO2021014259A1 publication Critical patent/WO2021014259A1/en

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
    • C02F1/003—Processes for the treatment of water whereby the filtration technique is of importance using household-type filters for producing potable water, e.g. pitchers, bottles, faucet mounted devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D27/00—Cartridge filters of the throw-away type
    • B01D27/02—Cartridge filters of the throw-away type with cartridges made from a mass of loose granular or fibrous material
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/288—Treatment of water, waste water, or sewage by sorption using composite sorbents, e.g. coated, impregnated, multi-layered
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/281—Treatment of water, waste water, or sewage by sorption using inorganic sorbents
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/28—Treatment of water, waste water, or sewage by sorption
    • C02F1/283—Treatment of water, waste water, or sewage by sorption using coal, charred products, or inorganic mixtures containing them
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/42—Treatment of water, waste water, or sewage by ion-exchange
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/42—Treatment of water, waste water, or sewage by ion-exchange
    • C02F2001/425—Treatment of water, waste water, or sewage by ion-exchange using cation exchangers
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/20—Heavy metals or heavy metal compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2201/00—Apparatus for treatment of water, waste water or sewage
    • C02F2201/002—Construction details of the apparatus
    • C02F2201/006—Cartridges
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2303/00—Specific treatment goals
    • C02F2303/22—Eliminating or preventing deposits, scale removal, scale prevention
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2307/00—Location of water treatment or water treatment device
    • C02F2307/04—Location of water treatment or water treatment device as part of a pitcher or jug

Definitions

  • the invention relates to gravity-type filtering modules for purifying drinking water and can be used to improve the quality of drinking water purification in household pitcher-type filters.
  • Household filters for the treatment of drinking water are currently widely used among the population as an alternative to bottled drinking water.
  • the most popular among them are gravity filters in the form of pitcher-type filters that are distinguished by their simple design, low price, and the fact that they do not require connection to pressurized water systems.
  • Pitcher-type filters consist of a vessel with a intake funnel in the upper part thereof, into which the water to be treated is poured, and a filtering module (cartridge) which is tightly connected to the funnel and performs water purification. Purified water is collected at the bottom of the pitcher.
  • US 2012/0012515, 2012; US 2009/0001011 , 2009; RU 2617775, 2017) comprise a plastic vessel accommodating a mixture of granular and/or fiber sorbent and filter materials (DE 000002919901 , 1980; WO 1998/017582, 1998; WO 2005/1 18481 , 2005, WO 2005/1 18104, 2005; WO 2005/1 18482, 2005;
  • the upper part of the plastic vessel is hermetically connected to an opening in the filter funnel through a filtering module fixing system, and the lower part of the plastic vessel is provided with one or more openings for releasing the purified water.
  • one or more openings are provided in the hermetic fixing system for water inlet and air outlet.
  • the gravity filter filtering modules comprising a filter medium made of porous block material are advantageous over the gravity filter filtering modules comprising a filter medium consisting of a mixture of granular or fiber sorbent and filter materials, since they provide consistently high effectiveness of water purification over their entire service life. This is the result of rigid fixation of the particles of the sorbent components in the porous block material, which does not lead to the formation of voids and cracks therein during the passage of air bubbles released from the treated water as it occurs in the volume of the filter medium consisting of a mixture of granular and/or fiber sorbent and filter materials.
  • gravity-type filtering modules comprising a filter medium made of porous block material compared to gravity filter filtering modules comprising a filter medium consisting of a mixture of granular and/or fiber sorbent and filter materials is the absence of smallest particles of sorbent materials in the purified water, especially during an initial filtration period, which due to their small size are not retained by fiber materials and meshes provided at the inlet and outlet of the filter module.
  • gravity filter filtering modules that comprise a filter medium made of porous block material
  • gravity filter filtering modules comprising a filter medium consisting of a mixture of granular and/or fiber sorbent and filter materials
  • they are not widely used, mainly because of their complex design and low filtration rates.
  • the closest prior art filtering module (US 2009/000101 1 , 2009) to the claimed invention comprises a filter element made of porous block material placed inside a plastic cylinder that has inlet and outlet openings, and a fixing system attached to a plastic body and to which the porous block material is hermetically attached.
  • This design involves the making of injection molded polymer parts of the plastic cylinder of the filtering module and its fixing system as well as the hermetic fastening of the porous filter material to the body of the fixing system and the hermetic fastening of the plastic cylinder to the fixing system.
  • This design of a filtering module with the porous filter element provided inside the plastic casing is distinguished by low filtration rates and an unsatisfactory water treatment capacity for the consumer, which is due to two factors: a) in the embodiment variant with the movement direction of the water being purified from the cavity between the plastic cylinder and the porous block material, air released from the water into the volume of the porous block material will accumulate in the upper part of the volume of the porous block material and, for lack of outlet, will block water filtration in the upper part of the porous block material, which results in a decrease in the filtration surface area and accordingly decrease in filtration rate and capacity; b) in the variant with the movement direction of the water being purified from the volume of the porous block material through the porous block material and into the cavity between the plastic cylinder and the porous block material, the filtered water will meet the resistance of the filtered water present in this cavity, which will slow down the filtration, and moreover released air will block part of the outer filter surface of the porous block material, which will adversely affect the
  • the composition used for making the porous block material contains a binder from the class of hydrophobic polymers with a melt index of less than 1.8 g/10 min as determined by ASTM D 1238 at 190 °C and a load of 25 kg, and that the compression of the starting mixture during molding of the porous block material is less than 10 %.
  • the binder does not reliably contact the particles of the starting mixture, resulting in a material with low mechanical strength, which is unable to fulfill the function of a filtering module casing.
  • An object of the present invention is to provide a gravity filter filtering module for purifying drinking water which has a simplified design and at the same time provides an increased filtration rate in combination with high effectiveness and high water purification capacity.
  • the proposed gravity filter filtering module for purifying drinking water which comprises a system for fixing the filtering module to the filter funnel, which has an opening for the inlet of water to be purified and for outlet of air, a filter element in the form of a hollow vertical vessel comprising a body made of porous block material and having a porous or hermetically sealed bottom, or in the form of a disk made of porous block material, wherein the porous block material is obtained by compression of a heated mixture of powdered starting components comprising activated carbon particles and polymer binder, or activated carbon particles, heavy metal sorbent, and polymer binder; and wherein the fixing system of the filtering module is connected to the filter element by an adhesive joint or by a mechanical connection.
  • the filter element may be made of porous block material in the form of a hollow vertical vessel with a cross-sectional shape for example in the form of a circle (hollow cylinder), square, rectangle, oval, or a complex contour, or in the form of a hollow inverse pyramid, or a hollow inverse cone, or a hollow inverse truncated pyramid or truncated inverse cone with a porous or hermetically sealed bottom, which has walls of consistent or differing thickness, or in the form of a disk of various shapes, which has smooth or ribbed upper and lower surfaces, for example.
  • a cross-sectional shape for example in the form of a circle (hollow cylinder), square, rectangle, oval, or a complex contour, or in the form of a hollow inverse pyramid, or a hollow inverse cone, or a hollow inverse truncated pyramid or truncated inverse cone with a porous or hermetically sealed bottom, which has walls of consistent or differing thickness, or in the form of a disk of various
  • the height of the filter element ranges between 10 mm and 100 mm, the outer diameter ranges between 35 mm and 100 mm.
  • the walls and of the porous bottom of the filter element have a thickness between 5 mm and 25 mm.
  • a heat-treated mixture of powdered materials is used, either consisting of activated carbon and a polymer binder with a melt index from 2 g to 20 g per 10 min according to ASTM D 1238 at 190 °C and a load of 25 kg, and with a particle size of the activated carbon and the polymer binder between 0.05 mm and 0.5 mm, preferably between 0.07 and 0.15 mm, with a ratio of activated carbon to polymer binder of (75 - 95):(5 - 25) wt%; or a heat-treated mixture of powdered materials consisting of activated carbon, a heavy metal sorbent, and a polymer binder with a melt index from 2 g to 20 g per 10 min according to ASTM D 1238 at 190 °C and a load of 25 kg, and with a particle size between 0.05 mm and 0.5 mm, preferably between 0.07 and 0.15 mm, with a ratio of activated carbon to
  • the heavy metal sorbent used include inorganic sorbents selected from the classes of zeolites, aluminum silicates, silica gels, aluminum oxide, zirconium dioxide, and/or organic sorbents based on cation-exchange resins and fibers.
  • the porous block material of the filter element is made either by an extrusion process or by a hot pressing process with a compression ratio of 12 - 25 % during molding, and at a temperature that is higher by 10 - 40 °C than the softening temperature of the polymer binder, and the polymers used as the polymer binder include polymers selected from the classes of polyolefins and/or polyesters and/or copolymers thereof, which have a melt index between 2 and 20 g per 10 min according to ASTM D 1238 at 190 °C and a load of 25 kg.
  • the fixing system of the filtering module is configured so as to allow the filtering module to be sealed tightly to the body of the filter funnel and comprises either a threaded unit connected to a threaded portion of the funnel, or a rim with elements providing for a tight fit to the funnel opening, and the fixing system is connected to the filter element by an adhesive joint using a melted polymer or any other adhesive material, or by a mechanical connection engaging on the inner or outer, or inner and outer surface(s) of the filter element.
  • the distinctive feature of the claimed invention is the fundamentally novel design of the filtering module, which does not require an additional device such as, for example, a plastic cylinder designed to accommodate filter material therein as is the case in the prototype, rather the filter element itself performs the function of a casing by being made of a porous block material in the form of a hollow vertical vessel with a porous or hermetically sealed bottom or in the form disk, which at the same time performs the function of a filter material.
  • the porous block material used exhibits increased mechanical strength due to the good bonding (adhesion) of the particles of the starting mixture, which is ensured by using a polymer binder with a melt index from 2 g to 20 g per 10 min according to ASTM D 1238 at 190 °C and a load of 25 kg, and by a compression ratio of 12 % to 25 % during molding, which allows to use it as a filter element body.
  • the invention provides a gravity filter filtering module for drinking water purification, which is characterized by a simple configuration, as it does not require an additional vessel for the filter material, while providing a high filtration rate from 250 to 500 cm 3 /min compared to the prototype, in combination with highly effective water purification from 92 % to 98 % and a filtering capacity of up to 450 liters.
  • the end plate (hermetically sealed bottom) may be made of a polymer such as polyethylene or polypropylene.
  • FIG. 1 is a schematic sectional view of a filter pitcher comprising a filtering module according to a first embodiment of the invention
  • FIG. 2 is a schematic sectional view of a filter pitcher with a filtering module according to a second embodiment of the invention
  • FIG. 3 is a schematic sectional view of a filter pitcher with a filtering module according to a third
  • FIGS. 4to 10 are schematic sectional views of different further embodiments of filtering modules according to the invention.
  • FIGS.1 1 and 12 each show a vertical section and a cross-sectional view of further embodiments of filtering modules according to the invention.
  • FIG. 13 shows a top plan view and a side elevational view of a further embodiment of the filtering
  • FIG. 1 is a schematic view of a filter pitcher 1 comprising an intake funnel 2, a filtering module 3 with a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5. Arrows indicate the direction of water flow during filtration.
  • FIG. 2 is a schematic view of a filter pitcher 1 comprising an intake funnel 2, a filtering module 3 with a filter element 4 in the form of a hollow cylinder with a porous bottom. Arrows indicate the direction of water flow during filtration.
  • FIG. 3 is a schematic view of a filter pitcher 1 comprising an intake funnel 2, a filtering module 3 with a filter element 4 in the form of a disk. Arrows indicate the direction of water flow during filtration.
  • FIG. 4 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5, and a fixing system 6 in the form of a threaded unit.
  • the porous block material of the filter element 4 is attached to the fixing system 6 and to the end plate 5 by an adhesive joint 8 at the end faces of the porous block material.
  • FIG. 5 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a porous bottom, and a fixing system 6 in the form of a threaded unit.
  • the porous block material of the filter element is attached to the fixing system 6 by an adhesive joint 8 at the end face of the porous block material.
  • Arrows indicate the direction of water flow during filtration.
  • FIG. 6 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder that has walls of differing thickness and a porous bottom, and a fixing system 6 in the form of a threaded unit.
  • the porous block material of the filter element is attached to the fixing system 6 by an adhesive joint 8 at the end face of the porous block material.
  • FIG. 7 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5, and a fixing system 6 in the form of a threaded unit.
  • the porous block material of the filter element is attached to the fixing system 6 and the end plate 5 by a mechanical connection 9 along the inner cylindrical surface of the porous block material.
  • FIG. 8 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5, and a fixing system 6 in the form of a threaded unit.
  • the porous block material of the filter element is attached to the fixing system 6 and to the end plate 5 by a mechanical connection 9 along the inner and outer cylindrical surfaces of the porous block material.
  • FIG. 9 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5, and a fixing system 6 in the form of a threaded unit.
  • the porous block material of the filter element is attached to the fixing system 6 and to the end plate 5 by a mechanical connection 9 on the outer cylindrical surface of the porous block material.
  • FIG. 10 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5.
  • the porous block material of the filter element is attached to the fixing system 7 in the form of a rim comprising elements for a tight fit to the funnel opening by an adhesive joint 8 along the outer surface of the porous block material, and to the end plate 5 by an adhesive joint 8 along the end face of the porous block material.
  • FIG. 1 1 shows sectional views of a filter element 4 which is in the form of a vertical hollow vessel with a hermetically sealed bottom end plate 5.
  • the porous block material of the filter element is attached to the fixing system 7 in the form of a rim comprising elements for a tight fit to the funnel opening by an adhesive joint 8 along the outer surface of the porous block material, and to the end plate 5 by an adhesive joint 8 along the end face of the porous block material.
  • FIG. 12 shows sectional views of a disk-shaped filter element 4.
  • the porous block material of the filter element is attached to the fixing system 7 in the form of a rim comprising elements for a tight fit to the funnel opening by an adhesive joint 8 on the outer surface of the porous block material.
  • FIG. 13 shows a top view and a side view of a filtering module comprising a filter element 4 in the form of a vertical hollow vessel with a cross-sectional shape in the form of a complex contour and with a hermetically sealed bottom end plate 5.
  • the porous block material of the filter element is attached to the fixing system 6 in the form of a threaded unit comprising elements tightly fitting to the funnel opening by an adhesive joint 8 along the outer surface of the porous block material, and to the end plate 5 by an adhesive joint 8 along the end face of the porous block material.
  • the design of the filtering module proposed in the present invention is characterized by simplicity, since it does not require any additional housing, for example made of plastics, and therefore no tight connection of such housing to the fixing system of the filter module.
  • the filter element 4 is connected to the fixing system either by adhesive bonding (FIGS. 4, 5, 6, 10, 1 1 , 12, 13), or by a mechanical connection using ripped inserts, or using an elastic clamping ring (FIG. 7), or by being crimped to the outer or inner vertical surfaces of the filter element (FIG. 9 shows an option of crimping to the outer vertical surface), or by being crimped to the outer and inner vertical surfaces of the filter element (FIG.
  • the water to be filtered flows from the intake funnel 2 placed in the filter pitcher 1 and through the filtering module 3 by entering the cavity of filter element 4 (FIGS. 1 , 2, 4 - 10), which is made in the form of a hollow cylinder with a hermetically sealed bottom end plate 5 (FIGS. 4, 7, 8, 9, 10), or in the form of a hollow cylinder with a porous bottom (FIGS. 5, 6), or in the form of a hollow cylinder with walls of differing thickness along its height and with a porous bottom (FIG. 6), or in the form of a hollow vertical vessel with an oval cross-sectional shape with a hermetically sealed bottom (FIG.
  • the water to be filtered passes through the lateral walls of the filter element and is collected in the bottom part of the filter pitcher, and in the case of the embodiments of the filtering module with a porous bottom, as shown in FIGS. 5, 6, the water to be filtered passes through the lateral walls and through the bottom of the filter element and is collected in the bottom part of the filter pitcher.
  • the air released from the passing water gets out either into the filter funnel through the inlet of the filter element, or through the porous walls and the porous bottom of the filter element into the interior of the pitcher and is not blocked in the filter surface of the filter element, as it occurs in the prototype patent, thereby ensuring filtration with high rate, high effectiveness, and high capacity.
  • Another factor ensuring a high filtration rate is that air released from the water is not blocked in the outer filter surface of the porous block material, as is the case in the prototype patent due to the presence of a plastic housing in the design of the filtering module.
  • the filter element of the filtering module is made with a wall thickness from 5 mm to 25 mm.
  • the boundary values of the range of wall thicknesses are selected because if the wall thickness is less than 5 mm, the filter element will have insufficient mechanical strength, and if the wall thickness of the filter element is more than 25 mm this will adversely affect the filtration rate due to the significant hydrodynamic resistance.
  • the selected embodiment of the filter element provides a predetermined water filtration rate by the filter element, which is proportional to the filtration surface area and which is minimal for a filter element in the form of a disk and for a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate, and which is maximal for a filter element with a porous bottom and complex cross- sectional shape, or by virtue of its manufacturing technology: filter elements in the form of a hollow cylinder with an end plate are produced by an extrusion process; filter elements in the form of a hollow cylinder with a porous bottom, a hollow vertical vessel with a cross-sectional shape in the form of an oval or a complex contour with a porous bottom, and in the form of a cone or pyramid with a porous bottom or without a porous bottom as well as in the form of a disk are produced by a hot pressing process.
  • the manufacturing process of the filter block is conducted at a temperature that is higher by 10 - 40 °C than the softening temperature of the polymer binder.
  • the formed block material of the filter element will lack strength, and at a temperature of more than 40 °C higher than the softening temperature of the polymer binder, a significant surface area of the sorbent will be blocked due to flowing of the polymer binder.
  • the compression ratio in a range of 12 - 25 % for the components of the granular starting material mixture is selected because this range ensures to obtain of porous material with sufficient mechanical strength. If the compression ratio is less than 12 %, the filter block will not have the necessary mechanical strength. With a compression ratio of more than 25 %, the resulting material will have small pores, which makes it difficult for the water to pass through.
  • the polymer binder is chosen from the classes of polyolefins (e.g. low pressure polyethylene, high pressure polyethylene, polypropylene) and/or polyesters (e.g. polyethylene terephthalate) and/or copolymers thereof (e.g. polyethylene vinyl acetate copolymer) due to their chemical inertness and insolubility in water on the one hand, and on the other hand due to their sufficiently low softening temperatures, which allows to intensify the manufacturing process of the filter element.
  • polyolefins e.g. low pressure polyethylene, high pressure polyethylene, polypropylene
  • polyesters e.g. polyethylene terephthalate
  • copolymers thereof e.g. polyethylene vinyl acetate copolymer
  • the embodiment of the filter element in the form of a hollow cylinder with walls of differing thickness and with a hermetically sealed bottom ensures consistent passage of the water to be purified through the walls of the filter element over the entire height thereof, since the increase in pressure of the water column in the cavity of the filter element from top to bottom is compensated by an increasing resistance to the passage of water through the walls due to the corresponding increase in the wall thickness of the filter element.
  • the porous block material of the filter element consists of a sorbent (e.g. activated carbon) and a polymer binder, or of a mixture of sorbents (e.g. activated carbon and heavy metal sorbents) and a polymer binder.
  • a sorbent e.g. activated carbon
  • a polymer binder e.g. polyethylene glycol
  • a mixture of sorbents e.g. activated carbon and heavy metal sorbents
  • sorbents and polymer binder are used in the form of a powder with a particle size from 0.05 mm to 0.5 mm, preferably 0.07 mm to 0.15 mm. If the particle size of the sorbents and the polymer binder is less than 0.05 mm, the hydrodynamic resistance of the porous block material increases, which leads to a decrease in filtration rate. If the particle size of the sorbents and the polymer binder is more than 0.5 mm, the effectiveness of water purification decreases due to a decrease in the actual filtration (sorption) surface area of the sorbent particles.
  • the composition of the starting mixture of the porous block material of the filter block is adapted.
  • a mixture of powdered materials consisting of activated carbon and a polymer binder with a ratio of activated carbon to polymer binder of (75 - 95):(5 - 25) wt%.
  • the significant amount of finely dispersed activated carbon contained in such a mixture provides for highly effective water purification from such toxic substances, achieving 92 % - 96 % over the entire service life (see the table below).
  • a mixture of powdered materials consisting of activated carbon, a heavy metal sorbent, and a polymer binder with a ratio of activated carbon to heavy metal sorbent to polymer binder of (30 - 70):(10 - 70):(5 - 20) wt%.
  • the significant amount of sorbents or of a mixture of heavy metal sorbents contained in such a mixture provides for highly effective water purification from such toxic substances, achieving 92 % - 98 % over the entire service life (see table).
  • inorganic sorbents from the classes of zeolites, aluminum silicates, silica gels, aluminum oxide, zirconium dioxide, and/or organic sorbents based on cation-exchange resins and fibers are used as the heavy metal sorbents.
  • exemplary embodiments of filtering modules are given, with filter elements of various shapes and compositions, and the table shows test results thereof with regard to filtration rate and water purification effectiveness.
  • the examples mentioned give an idea of the characteristics of the inventive filtering module, but should not be construed as exhaustive.
  • tests on the filtration rate and water purification effectiveness were performed with the filtering module placed in the funnel of a filter pitcher.
  • the filtration rate was estimated by measuring the time it took for the first liter of water to pass through the filter module, the effectiveness of water treatment was assessed in compliance with GOST 31952-2012 WATER TREATMENT DEVICES - General requirements for effectiveness and methods for its determination.
  • the filtering module comprises a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate with a fixing system in the form of a threaded unit that is connected to the filter element by gluing using melted polyethylene (FIG. 4).
  • Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall thickness 14 mm.
  • the starting mixture has the following composition: 85 wt% of activated carbon; 15 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C.
  • the constituents of the mixture have a particle size from 0.08 mm to 0.1 mm.
  • the filter element was made by an extrusion process at a temperature of 145 °C and with a compression ratio of the starting mixture of 15 %. The test results are presented in the table.
  • Example #2
  • the filtering module comprises a filter element in the form of a hollow cylinder with a porous bottom and a fixing system in the form of a threaded unit that is connected to the filter element by gluing using melted polyethylene (FIG. 5).
  • Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall and bottom thickness 14 mm.
  • the starting mixture has the following composition: 90 wt% of activated carbon; 10 wt% of polymer binder: a mixture of polyethylene terephthalate with polyethylene with a softening temperature of 1 15 °C.
  • the constituents of the mixture have a particle size from 0.08 mm to 0.1 mm.
  • the filter element was made by a hot pressing process at a temperature of 155 °C and with a compression ratio of the starting mixture of 12 %. The test results are presented in the table.
  • the filtering module comprises a filter element in the form of a hollow vertical vessel with an oval cross- sectional shape with a hermetically sealed bottom end plate with a fixing system in the form of a rim with elements for tightly fitting to the opening of the funnel, which is connected to the filter element by gluing using melted polyethylene (FIG. 4).
  • Dimensions of the filter element are: height 50 mm, outer large diameter 65 mm, outer small diameter 38 mm, wall thickness 9 mm.
  • the starting mixture has the following composition: 75 wt% of activated carbon; 25 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C.
  • the constituents of the mixture have a particle size from 0.08 mm to 0.1 mm.
  • the filter element was made by an extrusion process at a temperature of 135 °C and with a compression ratio of the starting mixture of 15 %. The test results are presented in the table.
  • the filtering module comprises a filter element in the form of a disk with a fixing system in the form of a rim with elements for tightly fitting to the opening of the funnel, which is connected to the filter element by gluing using melted polyethylene (FIG. 12).
  • Dimensions of the filter element are: height 30 mm, diameter 55 mm.
  • the starting mixture has the following composition: 85 wt% of activated carbon;
  • the filtering module comprises a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate with a fixing system in the form of a threaded unit which is connected to the filter element by gluing using melted polyethylene (FIG. 4).
  • Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall thickness 14 mm.
  • the starting mixture has the following composition: 40 wt% of activated carbon; 50 wt% of heavy metal sorbent: weakly acid carboxyl cation exchanger in Na + form; 10 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C.
  • the constituents of the mixture have a particle size from 0.08 mm to 0.1 mm.
  • the filter element was made by an extrusion process at a temperature of 145 °C and with a compression ratio of the starting mixture of 15 %. The test results are presented in the table.
  • the filtering module comprises a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate with a fixing system in the form of a threaded unit which is connected to the filter element by gluing using melted polyethylene (FIG. 4).
  • Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall thickness 20 mm.
  • the starting mixture has the following composition: 30 wt% of activated carbon; 60 wt% of heavy metal sorbent: synthetic zeolite brand KA-BS; 10 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C.
  • the constituents of the mixture have a particle size from 0.08 mm to 0.1 mm.
  • the filter element was made by an extrusion process at a temperature of 150 °C and with a compression ratio of the starting mixture of 12 %. The test results are presented in the table.
  • the filtering module comprises a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate with a fixing system in the form of a threaded unit which is connected to the filter element by gluing using melted polyethylene (FIG. 4).
  • Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall thickness 14 mm.
  • the starting mixture has the following composition: 40 wt% of activated carbon; 50 wt% of heavy metal sorbent which is a mixture of a weakly acid carboxylic cation exchanger in the Na + form and a synthetic brand zeolite KA-BS (in a ratio of 1 : 1 ); 10 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C.
  • the constituents of the mixture have a particle size from 0.08 mm to 0.1 mm.
  • the filter element was made by an extrusion process at a temperature of 145 °C and with a compression ratio of the starting mixture of 15 %. The test results are presented in the table. Table: Test results of filtering module according to the invention
  • the gravity filter filtering module according to the invention achieves high rate, high water treatment effectiveness, and high service life capacity of the filtering module, due to its design, composition and manufacturing technology of the filter element made of porous block material in the form of a vessel or disk.

Abstract

The invention is intended for the purification of drinking water and can be used to improve the quality of drinking water purification in household pitcher-type filters. The gravity filter filtering module comprises a system for fixing the filtering module to the filter funnel, which has an opening for the inlet of water to be purified and for outlet of air; a filter element in the form of a hollow vertical vessel comprising a body made of porous block material with a porous or hermetically sealed bottom, or in the form of a disk made of porous block material. The porous block material is obtained by compression of a heated mixture of powdered starting components comprising activated carbon particles and polymer binder or activated carbon particles, heavy metal sorbent, and polymer binder. The fixing system of the filtering module is connected to the filter element by an adhesive joint or by a mechanical connection. The technical result is the creation of a gravity filter filtering module for drinking water purification, which is characterized by simplicity of its design and by providing a high filtration rate in combination with high effectiveness of water purification of 92 % - 98 % and an operating capacity of the filtering module of up to 450 liters.

Description

GRAVITY FILTER FILTERING MODULE FOR PURIFICATION OF DRINKING WATER
The invention relates to gravity-type filtering modules for purifying drinking water and can be used to improve the quality of drinking water purification in household pitcher-type filters.
Prior art
Household filters for the treatment of drinking water are currently widely used among the population as an alternative to bottled drinking water. The most popular among them are gravity filters in the form of pitcher-type filters that are distinguished by their simple design, low price, and the fact that they do not require connection to pressurized water systems.
Pitcher-type filters consist of a vessel with a intake funnel in the upper part thereof, into which the water to be treated is poured, and a filtering module (cartridge) which is tightly connected to the funnel and performs water purification. Purified water is collected at the bottom of the pitcher.
Gravity filter filtering modules of known designs (DE 000002919901 , 1980; WO 1998/017582, 1998;
WO 2005/1 18481 , 2005; WO 2005/1 18104, 2005; WO 2005/1 18482, 2005; US 2008/01 10820, 2008;
US 2012/0012515, 2012; US 2009/0001011 , 2009; RU 2617775, 2017) comprise a plastic vessel accommodating a mixture of granular and/or fiber sorbent and filter materials (DE 000002919901 , 1980; WO 1998/017582, 1998; WO 2005/1 18481 , 2005, WO 2005/1 18104, 2005; WO 2005/1 18482, 2005;
RU 2617775, 2017), or porous block material containing sorbents (US 2008/01 10820, 2008;
US 2009/0001011 , 2009). The upper part of the plastic vessel is hermetically connected to an opening in the filter funnel through a filtering module fixing system, and the lower part of the plastic vessel is provided with one or more openings for releasing the purified water. To allow the water to enter the plastic vessel with sorbent and filtering materials, one or more openings are provided in the hermetic fixing system for water inlet and air outlet.
The gravity filter filtering modules comprising a filter medium made of porous block material are advantageous over the gravity filter filtering modules comprising a filter medium consisting of a mixture of granular or fiber sorbent and filter materials, since they provide consistently high effectiveness of water purification over their entire service life. This is the result of rigid fixation of the particles of the sorbent components in the porous block material, which does not lead to the formation of voids and cracks therein during the passage of air bubbles released from the treated water as it occurs in the volume of the filter medium consisting of a mixture of granular and/or fiber sorbent and filter materials. The presence of such voids and cracks is the reason for the deterioration of water purification quality in gravity-type filter modules that comprise a filter medium consisting of a mixture of granular or fiber sorbent and filter materials, since part of the water to be purified will follow the path of least resistance through the cracks and voids, without contacting the filter medium. Another advantage of gravity-type filtering modules comprising a filter medium made of porous block material compared to gravity filter filtering modules comprising a filter medium consisting of a mixture of granular and/or fiber sorbent and filter materials is the absence of smallest particles of sorbent materials in the purified water, especially during an initial filtration period, which due to their small size are not retained by fiber materials and meshes provided at the inlet and outlet of the filter module.
Despite of the mentioned advantages of the gravity filter filtering modules that comprise a filter medium made of porous block material over gravity filter filtering modules comprising a filter medium consisting of a mixture of granular and/or fiber sorbent and filter materials, they are not widely used, mainly because of their complex design and low filtration rates.
The closest prior art filtering module (US 2009/000101 1 , 2009) to the claimed invention (i.e. the prototype) comprises a filter element made of porous block material placed inside a plastic cylinder that has inlet and outlet openings, and a fixing system attached to a plastic body and to which the porous block material is hermetically attached. This design involves the making of injection molded polymer parts of the plastic cylinder of the filtering module and its fixing system as well as the hermetic fastening of the porous filter material to the body of the fixing system and the hermetic fastening of the plastic cylinder to the fixing system. This design of a filtering module with the porous filter element provided inside the plastic casing is distinguished by low filtration rates and an unsatisfactory water treatment capacity for the consumer, which is due to two factors: a) in the embodiment variant with the movement direction of the water being purified from the cavity between the plastic cylinder and the porous block material, air released from the water into the volume of the porous block material will accumulate in the upper part of the volume of the porous block material and, for lack of outlet, will block water filtration in the upper part of the porous block material, which results in a decrease in the filtration surface area and accordingly decrease in filtration rate and capacity; b) in the variant with the movement direction of the water being purified from the volume of the porous block material through the porous block material and into the cavity between the plastic cylinder and the porous block material, the filtered water will meet the resistance of the filtered water present in this cavity, which will slow down the filtration, and moreover released air will block part of the outer filter surface of the porous block material, which will adversely affect the filtration capacity during operation of the filtering module. The aforementioned problems with complex design, low filtration rate and poor service life for the consumer of filtering modules with a filter element made of porous block material could be solved if there was no plastic casing in the filter module, that is, if the filter element made of porous block material would simultaneously fulfil the functions of a filtering module casing and a filter element. For this purpose, a filter element made of porous block material must possess high mechanical strength, in addition to the capability of purifying water. However, in the prototype patent, the material of the filtering module is not able to provide sufficient mechanical strength to the structure of the filter module, due to the characteristics of the polymer binder and its manufacturing technology. This is due to the fact that the composition used for making the porous block material contains a binder from the class of hydrophobic polymers with a melt index of less than 1.8 g/10 min as determined by ASTM D 1238 at 190 °C and a load of 25 kg, and that the compression of the starting mixture during molding of the porous block material is less than 10 %. With such an extremely low melt index of the binder and such a low compression ratio, the binder does not reliably contact the particles of the starting mixture, resulting in a material with low mechanical strength, which is unable to fulfill the function of a filtering module casing.
Figure imgf000005_0001
An object of the present invention is to provide a gravity filter filtering module for purifying drinking water which has a simplified design and at the same time provides an increased filtration rate in combination with high effectiveness and high water purification capacity.
The stated technical object is achieved by the proposed gravity filter filtering module for purifying drinking water, which comprises a system for fixing the filtering module to the filter funnel, which has an opening for the inlet of water to be purified and for outlet of air, a filter element in the form of a hollow vertical vessel comprising a body made of porous block material and having a porous or hermetically sealed bottom, or in the form of a disk made of porous block material, wherein the porous block material is obtained by compression of a heated mixture of powdered starting components comprising activated carbon particles and polymer binder, or activated carbon particles, heavy metal sorbent, and polymer binder; and wherein the fixing system of the filtering module is connected to the filter element by an adhesive joint or by a mechanical connection. The filter element may be made of porous block material in the form of a hollow vertical vessel with a cross-sectional shape for example in the form of a circle (hollow cylinder), square, rectangle, oval, or a complex contour, or in the form of a hollow inverse pyramid, or a hollow inverse cone, or a hollow inverse truncated pyramid or truncated inverse cone with a porous or hermetically sealed bottom, which has walls of consistent or differing thickness, or in the form of a disk of various shapes, which has smooth or ribbed upper and lower surfaces, for example.
The height of the filter element ranges between 10 mm and 100 mm, the outer diameter ranges between 35 mm and 100 mm.
The walls and of the porous bottom of the filter element have a thickness between 5 mm and 25 mm.
For the porous block material of the filter element, a heat-treated mixture of powdered materials is used, either consisting of activated carbon and a polymer binder with a melt index from 2 g to 20 g per 10 min according to ASTM D 1238 at 190 °C and a load of 25 kg, and with a particle size of the activated carbon and the polymer binder between 0.05 mm and 0.5 mm, preferably between 0.07 and 0.15 mm, with a ratio of activated carbon to polymer binder of (75 - 95):(5 - 25) wt%; or a heat-treated mixture of powdered materials consisting of activated carbon, a heavy metal sorbent, and a polymer binder with a melt index from 2 g to 20 g per 10 min according to ASTM D 1238 at 190 °C and a load of 25 kg, and with a particle size between 0.05 mm and 0.5 mm, preferably between 0.07 and 0.15 mm, with a ratio of activated carbon to heavy metal sorbent to polymer binder of (30 - 70):(10 - 70):(5 - 20) wt%. The heavy metal sorbent used include inorganic sorbents selected from the classes of zeolites, aluminum silicates, silica gels, aluminum oxide, zirconium dioxide, and/or organic sorbents based on cation-exchange resins and fibers.
The porous block material of the filter element is made either by an extrusion process or by a hot pressing process with a compression ratio of 12 - 25 % during molding, and at a temperature that is higher by 10 - 40 °C than the softening temperature of the polymer binder, and the polymers used as the polymer binder include polymers selected from the classes of polyolefins and/or polyesters and/or copolymers thereof, which have a melt index between 2 and 20 g per 10 min according to ASTM D 1238 at 190 °C and a load of 25 kg.
The fixing system of the filtering module is configured so as to allow the filtering module to be sealed tightly to the body of the filter funnel and comprises either a threaded unit connected to a threaded portion of the funnel, or a rim with elements providing for a tight fit to the funnel opening, and the fixing system is connected to the filter element by an adhesive joint using a melted polymer or any other adhesive material, or by a mechanical connection engaging on the inner or outer, or inner and outer surface(s) of the filter element.
The distinctive feature of the claimed invention is the fundamentally novel design of the filtering module, which does not require an additional device such as, for example, a plastic cylinder designed to accommodate filter material therein as is the case in the prototype, rather the filter element itself performs the function of a casing by being made of a porous block material in the form of a hollow vertical vessel with a porous or hermetically sealed bottom or in the form disk, which at the same time performs the function of a filter material. The porous block material used exhibits increased mechanical strength due to the good bonding (adhesion) of the particles of the starting mixture, which is ensured by using a polymer binder with a melt index from 2 g to 20 g per 10 min according to ASTM D 1238 at 190 °C and a load of 25 kg, and by a compression ratio of 12 % to 25 % during molding, which allows to use it as a filter element body.
As a technical result, the invention provides a gravity filter filtering module for drinking water purification, which is characterized by a simple configuration, as it does not require an additional vessel for the filter material, while providing a high filtration rate from 250 to 500 cm3/min compared to the prototype, in combination with highly effective water purification from 92 % to 98 % and a filtering capacity of up to 450 liters.
The essence of the invention will become apparent with reference to the drawings.
The end plate (hermetically sealed bottom) may be made of a polymer such as polyethylene or polypropylene.
Brief Description of the Drawings
FIG. 1 is a schematic sectional view of a filter pitcher comprising a filtering module according to a first embodiment of the invention;
FIG. 2 is a schematic sectional view of a filter pitcher with a filtering module according to a second embodiment of the invention;
FIG. 3 is a schematic sectional view of a filter pitcher with a filtering module according to a third
embodiment of the invention; FIGS. 4to 10 are schematic sectional views of different further embodiments of filtering modules according to the invention;
FIGS.1 1 and 12 each show a vertical section and a cross-sectional view of further embodiments of filtering modules according to the invention; and
FIG. 13 shows a top plan view and a side elevational view of a further embodiment of the filtering
module according to the invention.
Detailed Description of Exemplary Embodiments
FIG. 1 is a schematic view of a filter pitcher 1 comprising an intake funnel 2, a filtering module 3 with a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5. Arrows indicate the direction of water flow during filtration.
FIG. 2 is a schematic view of a filter pitcher 1 comprising an intake funnel 2, a filtering module 3 with a filter element 4 in the form of a hollow cylinder with a porous bottom. Arrows indicate the direction of water flow during filtration.
FIG. 3 is a schematic view of a filter pitcher 1 comprising an intake funnel 2, a filtering module 3 with a filter element 4 in the form of a disk. Arrows indicate the direction of water flow during filtration.
FIG. 4 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5, and a fixing system 6 in the form of a threaded unit. The porous block material of the filter element 4 is attached to the fixing system 6 and to the end plate 5 by an adhesive joint 8 at the end faces of the porous block material.
FIG. 5 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a porous bottom, and a fixing system 6 in the form of a threaded unit. The porous block material of the filter element is attached to the fixing system 6 by an adhesive joint 8 at the end face of the porous block material. Arrows indicate the direction of water flow during filtration.
FIG. 6 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder that has walls of differing thickness and a porous bottom, and a fixing system 6 in the form of a threaded unit. The porous block material of the filter element is attached to the fixing system 6 by an adhesive joint 8 at the end face of the porous block material. FIG. 7 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5, and a fixing system 6 in the form of a threaded unit. The porous block material of the filter element is attached to the fixing system 6 and the end plate 5 by a mechanical connection 9 along the inner cylindrical surface of the porous block material.
FIG. 8 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5, and a fixing system 6 in the form of a threaded unit. The porous block material of the filter element is attached to the fixing system 6 and to the end plate 5 by a mechanical connection 9 along the inner and outer cylindrical surfaces of the porous block material.
FIG. 9 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5, and a fixing system 6 in the form of a threaded unit. The porous block material of the filter element is attached to the fixing system 6 and to the end plate 5 by a mechanical connection 9 on the outer cylindrical surface of the porous block material.
FIG. 10 shows a filtering module 3 comprising a filter element 4 in the form of a hollow cylinder with a hermetically sealed bottom end plate 5. The porous block material of the filter element is attached to the fixing system 7 in the form of a rim comprising elements for a tight fit to the funnel opening by an adhesive joint 8 along the outer surface of the porous block material, and to the end plate 5 by an adhesive joint 8 along the end face of the porous block material.
FIG. 1 1 shows sectional views of a filter element 4 which is in the form of a vertical hollow vessel with a hermetically sealed bottom end plate 5. The porous block material of the filter element is attached to the fixing system 7 in the form of a rim comprising elements for a tight fit to the funnel opening by an adhesive joint 8 along the outer surface of the porous block material, and to the end plate 5 by an adhesive joint 8 along the end face of the porous block material.
FIG. 12 shows sectional views of a disk-shaped filter element 4. The porous block material of the filter element is attached to the fixing system 7 in the form of a rim comprising elements for a tight fit to the funnel opening by an adhesive joint 8 on the outer surface of the porous block material.
FIG. 13 shows a top view and a side view of a filtering module comprising a filter element 4 in the form of a vertical hollow vessel with a cross-sectional shape in the form of a complex contour and with a hermetically sealed bottom end plate 5. The porous block material of the filter element is attached to the fixing system 6 in the form of a threaded unit comprising elements tightly fitting to the funnel opening by an adhesive joint 8 along the outer surface of the porous block material, and to the end plate 5 by an adhesive joint 8 along the end face of the porous block material.
The design of the filtering module proposed in the present invention is characterized by simplicity, since it does not require any additional housing, for example made of plastics, and therefore no tight connection of such housing to the fixing system of the filter module. The filter element 4 is connected to the fixing system either by adhesive bonding (FIGS. 4, 5, 6, 10, 1 1 , 12, 13), or by a mechanical connection using ripped inserts, or using an elastic clamping ring (FIG. 7), or by being crimped to the outer or inner vertical surfaces of the filter element (FIG. 9 shows an option of crimping to the outer vertical surface), or by being crimped to the outer and inner vertical surfaces of the filter element (FIG.
8). As the proposed filtering module does not have a polymer plastic housing, as shown in FIGS. 1 - 3, the water to be filtered flows from the intake funnel 2 placed in the filter pitcher 1 and through the filtering module 3 by entering the cavity of filter element 4 (FIGS. 1 , 2, 4 - 10), which is made in the form of a hollow cylinder with a hermetically sealed bottom end plate 5 (FIGS. 4, 7, 8, 9, 10), or in the form of a hollow cylinder with a porous bottom (FIGS. 5, 6), or in the form of a hollow cylinder with walls of differing thickness along its height and with a porous bottom (FIG. 6), or in the form of a hollow vertical vessel with an oval cross-sectional shape with a hermetically sealed bottom (FIG. 1 1), or in the form of a hollow vertical vessel with an oval cross-sectional shape with a porous bottom (not shown), or in the form of a hollow vertical vessel with a cross-sectional shape in the form of a complex contour with a hermetically sealed bottom (FIG. 13), or in the form of a hollow vertical vessel with a cross-sectional shape in the form of a complex contour with a porous bottom (not shown), or in the form of a hollow inverse cone (not shown), or in the form of a hollow inverse pyramid (not shown), or in the form of a hollow truncated inverse cone (not shown), or in the form of a hollow truncated inverse pyramid (not shown), or passes directly through a porous block material made in the form of a disk (FIG. 12) which has smooth or ribbed upper and lower surfaces, for example. Further, in the case of the embodiments of the filtering module with a hermetically sealed bottom end plate 5 for the filter element, as shown in FIGS. 4, 7, 8, 9, 10, the water to be filtered passes through the lateral walls of the filter element and is collected in the bottom part of the filter pitcher, and in the case of the embodiments of the filtering module with a porous bottom, as shown in FIGS. 5, 6, the water to be filtered passes through the lateral walls and through the bottom of the filter element and is collected in the bottom part of the filter pitcher.
In this case, the air released from the passing water gets out either into the filter funnel through the inlet of the filter element, or through the porous walls and the porous bottom of the filter element into the interior of the pitcher and is not blocked in the filter surface of the filter element, as it occurs in the prototype patent, thereby ensuring filtration with high rate, high effectiveness, and high capacity.
Another factor ensuring a high filtration rate is that air released from the water is not blocked in the outer filter surface of the porous block material, as is the case in the prototype patent due to the presence of a plastic housing in the design of the filtering module.
In order to ensure a high filtration rate in combination with high effectiveness of water purification from the toxic contaminants that are most common in centralized water supply sources (chlorine, organochlorine compounds, heavy metals) and an increased service life of the filter module, the filter element of the filtering module is made with a wall thickness from 5 mm to 25 mm. The boundary values of the range of wall thicknesses are selected because if the wall thickness is less than 5 mm, the filter element will have insufficient mechanical strength, and if the wall thickness of the filter element is more than 25 mm this will adversely affect the filtration rate due to the significant hydrodynamic resistance.
The selected embodiment of the filter element provides a predetermined water filtration rate by the filter element, which is proportional to the filtration surface area and which is minimal for a filter element in the form of a disk and for a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate, and which is maximal for a filter element with a porous bottom and complex cross- sectional shape, or by virtue of its manufacturing technology: filter elements in the form of a hollow cylinder with an end plate are produced by an extrusion process; filter elements in the form of a hollow cylinder with a porous bottom, a hollow vertical vessel with a cross-sectional shape in the form of an oval or a complex contour with a porous bottom, and in the form of a cone or pyramid with a porous bottom or without a porous bottom as well as in the form of a disk are produced by a hot pressing process. Furthermore, in order to provide the sorbent material of the filter element with a surface area that is accessible to the best possible extent for sorption, the manufacturing process of the filter block is conducted at a temperature that is higher by 10 - 40 °C than the softening temperature of the polymer binder. At a temperature that is higher by less than 10 °C than the softening temperature of the polymer binder, the formed block material of the filter element will lack strength, and at a temperature of more than 40 °C higher than the softening temperature of the polymer binder, a significant surface area of the sorbent will be blocked due to flowing of the polymer binder.
The compression ratio in a range of 12 - 25 % for the components of the granular starting material mixture is selected because this range ensures to obtain of porous material with sufficient mechanical strength. If the compression ratio is less than 12 %, the filter block will not have the necessary mechanical strength. With a compression ratio of more than 25 %, the resulting material will have small pores, which makes it difficult for the water to pass through.
The polymer binder is chosen from the classes of polyolefins (e.g. low pressure polyethylene, high pressure polyethylene, polypropylene) and/or polyesters (e.g. polyethylene terephthalate) and/or copolymers thereof (e.g. polyethylene vinyl acetate copolymer) due to their chemical inertness and insolubility in water on the one hand, and on the other hand due to their sufficiently low softening temperatures, which allows to intensify the manufacturing process of the filter element.
The embodiment of the filter element in the form of a hollow cylinder with walls of differing thickness and with a hermetically sealed bottom ensures consistent passage of the water to be purified through the walls of the filter element over the entire height thereof, since the increase in pressure of the water column in the cavity of the filter element from top to bottom is compensated by an increasing resistance to the passage of water through the walls due to the corresponding increase in the wall thickness of the filter element.
In order to ensure effective purification of water from centralized water sources from the most common toxic contaminants (chlorine, organochlorine compounds, heavy metal cations), the porous block material of the filter element consists of a sorbent (e.g. activated carbon) and a polymer binder, or of a mixture of sorbents (e.g. activated carbon and heavy metal sorbents) and a polymer binder.
Furthermore, in order to achieve high effectiveness of water purification, all constituents used (sorbents and polymer binder) are used in the form of a powder with a particle size from 0.05 mm to 0.5 mm, preferably 0.07 mm to 0.15 mm. If the particle size of the sorbents and the polymer binder is less than 0.05 mm, the hydrodynamic resistance of the porous block material increases, which leads to a decrease in filtration rate. If the particle size of the sorbents and the polymer binder is more than 0.5 mm, the effectiveness of water purification decreases due to a decrease in the actual filtration (sorption) surface area of the sorbent particles.
In order to achieve the maximum selective purification of the water from toxic contaminants such as from chlorine or organochlorine compounds, or from heavy metals, or from chlorine and organochlorine compounds and heavy metals, the composition of the starting mixture of the porous block material of the filter block is adapted. Thus, to purify water from chlorine and organochlorine compounds, a mixture of powdered materials is used consisting of activated carbon and a polymer binder with a ratio of activated carbon to polymer binder of (75 - 95):(5 - 25) wt%. The significant amount of finely dispersed activated carbon contained in such a mixture provides for highly effective water purification from such toxic substances, achieving 92 % - 96 % over the entire service life (see the table below). To purify water from heavy metals, a mixture of powdered materials is used consisting of activated carbon, a heavy metal sorbent, and a polymer binder with a ratio of activated carbon to heavy metal sorbent to polymer binder of (30 - 70):(10 - 70):(5 - 20) wt%. The significant amount of sorbents or of a mixture of heavy metal sorbents contained in such a mixture provides for highly effective water purification from such toxic substances, achieving 92 % - 98 % over the entire service life (see table). In the present case, inorganic sorbents from the classes of zeolites, aluminum silicates, silica gels, aluminum oxide, zirconium dioxide, and/or organic sorbents based on cation-exchange resins and fibers are used as the heavy metal sorbents.
Below, exemplary embodiments of filtering modules are given, with filter elements of various shapes and compositions, and the table shows test results thereof with regard to filtration rate and water purification effectiveness. The examples mentioned give an idea of the characteristics of the inventive filtering module, but should not be construed as exhaustive. In the examples given, tests on the filtration rate and water purification effectiveness were performed with the filtering module placed in the funnel of a filter pitcher. The filtration rate was estimated by measuring the time it took for the first liter of water to pass through the filter module, the effectiveness of water treatment was assessed in compliance with GOST 31952-2012 WATER TREATMENT DEVICES - General requirements for effectiveness and methods for its determination.
The invention will now be illustrated by the following exemplary embodiments, without however being limited in its scope thereby.
Example #1
The filtering module comprises a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate with a fixing system in the form of a threaded unit that is connected to the filter element by gluing using melted polyethylene (FIG. 4). Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall thickness 14 mm. The starting mixture has the following composition: 85 wt% of activated carbon; 15 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C. The constituents of the mixture have a particle size from 0.08 mm to 0.1 mm. The filter element was made by an extrusion process at a temperature of 145 °C and with a compression ratio of the starting mixture of 15 %. The test results are presented in the table. Example #2
The filtering module comprises a filter element in the form of a hollow cylinder with a porous bottom and a fixing system in the form of a threaded unit that is connected to the filter element by gluing using melted polyethylene (FIG. 5). Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall and bottom thickness 14 mm. The starting mixture has the following composition: 90 wt% of activated carbon; 10 wt% of polymer binder: a mixture of polyethylene terephthalate with polyethylene with a softening temperature of 1 15 °C. The constituents of the mixture have a particle size from 0.08 mm to 0.1 mm. The filter element was made by a hot pressing process at a temperature of 155 °C and with a compression ratio of the starting mixture of 12 %. The test results are presented in the table.
Example #3
The filtering module comprises a filter element in the form of a hollow vertical vessel with an oval cross- sectional shape with a hermetically sealed bottom end plate with a fixing system in the form of a rim with elements for tightly fitting to the opening of the funnel, which is connected to the filter element by gluing using melted polyethylene (FIG. 4). Dimensions of the filter element are: height 50 mm, outer large diameter 65 mm, outer small diameter 38 mm, wall thickness 9 mm. The starting mixture has the following composition: 75 wt% of activated carbon; 25 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C. The constituents of the mixture have a particle size from 0.08 mm to 0.1 mm. The filter element was made by an extrusion process at a temperature of 135 °C and with a compression ratio of the starting mixture of 15 %. The test results are presented in the table.
Example #4
The filtering module comprises a filter element in the form of a disk with a fixing system in the form of a rim with elements for tightly fitting to the opening of the funnel, which is connected to the filter element by gluing using melted polyethylene (FIG. 12). Dimensions of the filter element are: height 30 mm, diameter 55 mm. The starting mixture has the following composition: 85 wt% of activated carbon;
15 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C. The constituents of the mixture have a particle size from 0.08 mm to 0.1 mm. The filter element was made by a hot pressing process at a temperature of 155 °C and with a compression ratio of the starting mixture of 12 %. The test results are presented in the table.
Example #5
The filtering module comprises a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate with a fixing system in the form of a threaded unit which is connected to the filter element by gluing using melted polyethylene (FIG. 4). Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall thickness 14 mm. The starting mixture has the following composition: 40 wt% of activated carbon; 50 wt% of heavy metal sorbent: weakly acid carboxyl cation exchanger in Na+ form; 10 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C. The constituents of the mixture have a particle size from 0.08 mm to 0.1 mm. The filter element was made by an extrusion process at a temperature of 145 °C and with a compression ratio of the starting mixture of 15 %. The test results are presented in the table.
Example #6
The filtering module comprises a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate with a fixing system in the form of a threaded unit which is connected to the filter element by gluing using melted polyethylene (FIG. 4). Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall thickness 20 mm. The starting mixture has the following composition: 30 wt% of activated carbon; 60 wt% of heavy metal sorbent: synthetic zeolite brand KA-BS; 10 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C. The constituents of the mixture have a particle size from 0.08 mm to 0.1 mm. The filter element was made by an extrusion process at a temperature of 150 °C and with a compression ratio of the starting mixture of 12 %. The test results are presented in the table.
Example #7
The filtering module comprises a filter element in the form of a hollow cylinder with a hermetically sealed bottom end plate with a fixing system in the form of a threaded unit which is connected to the filter element by gluing using melted polyethylene (FIG. 4). Dimensions of the filter element are: height 70 mm, outer diameter 62 mm, wall thickness 14 mm. The starting mixture has the following composition: 40 wt% of activated carbon; 50 wt% of heavy metal sorbent which is a mixture of a weakly acid carboxylic cation exchanger in the Na+ form and a synthetic brand zeolite KA-BS (in a ratio of 1 : 1 ); 10 wt% of polymer binder: low pressure polyethylene with a softening temperature of 1 15 °C. The constituents of the mixture have a particle size from 0.08 mm to 0.1 mm. The filter element was made by an extrusion process at a temperature of 145 °C and with a compression ratio of the starting mixture of 15 %. The test results are presented in the table. Table: Test results of filtering module according to the invention
Figure imgf000016_0001
x Sample made using equivalent components as specified in prototype patent (US 2009000101 1 , 2009) acc. to the technology described in the patent and in compliance with the dimensions specified in the patent.
As will be apparent from the results in the table, the gravity filter filtering module according to the invention achieves high rate, high water treatment effectiveness, and high service life capacity of the filtering module, due to its design, composition and manufacturing technology of the filter element made of porous block material in the form of a vessel or disk.
List of Reference Numerals:
1 Pitcher
2 Intake funnel
3 Filtering module
4 Filter element made of porous block material
5 End plate (hermetically sealed bottom)
6 Fixing system (threaded unit)
7 Fixing system (rim with elements for fitting to funnel socket) 8 Adhesive joint between fixing system and filter element
9 Mechanical connection between fixing system and filter element

Claims

Claims:
1. A gravity filter filtering module (3) for purifying drinking water, comprising
a system (6; 7) for fixing the filtering module (3) to a filter funnel (2), which has an opening for inlet of water to be purified and for outlet of air;
a filter element (4) in the form of a hollow vertical vessel comprising a body made of porous block material and having a porous or hermetically sealed bottom, or in the form of a disk made of porous block material;
wherein the porous block material is obtained by compression of a heated mixture of powdered starting components comprising activated carbon particles and polymer binder or activated carbon particles, heavy metal sorbent, and polymer binder; and
wherein the fixing system (6; 7) of the filtering module is connected to the filter element (4) by an adhesive joint (8) or by a mechanical connection (9).
2. The filtering module (3) according to claim 1 , characterized in that the filter element (4) is made of porous block material in the form of a hollow vertical vessel with a cross-sectional shape for example in the form of a circle, square, rectangle, oval, or complex contour, or in the form of a hollow inverse pyramid, or a hollow inverse cone or a hollow inverse truncated pyramid or truncated inverse cone with a porous or hermetically sealed bottom, which has walls of consistent or differing thickness, or in the form of a disk of various shapes.
3. The filtering module (3) according to claim 1 , characterized in that the filter element body (4) has a wall thickness from 5 mm to 25 mm.
4. The filtering module (3) according to claim 1 , characterized in that the porous block material of the filter element (4) is made from a heat-treated mixture of powdered materials comprising activated carbon with a iodine index of more than 1000 mg/g and a polymer binder, with a particle size of the activated carbon and the polymer binder from 0.05 mm to 0.5 mm, preferably from 0.07 mm to 0.15 mm, and with a ratio of activated carbon to polymer binder of
75 - 95 : 5 - 25 wt%.
5. The filtering module (3) according to claim 1 , characterized in that the porous block material of the filter element (4) is made from a heat-treated mixture of powdered materials comprising activated carbon, heavy metal sorbent and polymer binder with a particle size from 0.05 mm to 0.5 mm, preferably from 0.07 mm to 0.15 mm, with a ratio of activated carbon to heavy metal sorbent to polymer binder of 30 - 70 : 10 - 70 : 5 - 20 wt%.
6. The filtering module (3) according to claim 1 , characterized in that the heavy metal sorbent used in the porous block material of the filter element (4) comprises inorganic sorbents selected from the classes of zeolites, aluminum silicates, silica gels, aluminum oxide, zirconium dioxide, and/or organic sorbents based on cation-exchange resins and fibers.
7. The filtering module (3) according to claim 1 , characterized in that the porous block material of the filter element (4) is made either by an extrusion process or by a hot pressing process with a compression ratio during molding of 12 - 25 % at a temperature that is higher by 10 - 40 °C than the softening temperature of the polymer binder, and wherein polymers used as the polymer binder include polymers from the classes of polyolefins and/or polyesters and/or copolymers thereof with a melt index of 2 to 20 g per 10 min according to ASTM D 1238 at 190 °C and a load of 25 kgf.
8. The filtering module (3) according to claim 1 , characterized in that the fixing system (6; 7) of the filtering module (3) is configured for mounting the filtering module (3) to the body of the filter funnel (2) in a hermetically sealing manner, and is in the form of a threaded unit (6) that is connected to a threaded portion of the funnel, or in the form of a rim (7) which has elements for a tight fit to the funnel opening, wherein the fixing system (6; 7) is connected to the filter element body (4) by an adhesive joint (8) using melted polymer or any other adhesive material, or by a mechanical connection (9) engaging on the inner or outer surface or both surfaces of the filter element.
PCT/IB2020/056449 2019-07-25 2020-07-09 Gravity filter filtering device for softening and purifying driniking water WO2021014259A1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023135156A1 (en) * 2022-01-11 2023-07-20 Waterdrop Microdrink Gmbh Device for holding a filter pad for water purification

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2731706C1 (en) * 2020-02-14 2020-09-08 Акционерное общество "БВТ БАРЬЕР РУС" (АО "БВТ БАРЬЕР РУС") Porous block filter material for complex purification of drinking water and a method for production thereof
RU2747923C1 (en) * 2020-10-07 2021-05-17 Акционерное общество "БВТ БАРЬЕР РУС" (АО "БВТ БАРЬЕР РУС") Gravity filter filtering device for softening and purifying drinking water

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2919901A1 (en) 1979-05-17 1980-11-20 Itter Chemie Brita Geraete WATER PURIFICATION DEVICE
WO1998017582A1 (en) 1996-10-17 1998-04-30 Brita Gmbh A water treatment cartridge for use in domestic water treatment apparatus and domestic water treatment apparatus including such a cartridge
WO2005118482A1 (en) 2004-05-28 2005-12-15 Brita Gmbh Filter cartridge and device for filtering liquids
WO2005118104A1 (en) 2004-05-28 2005-12-15 Brita Gmbh Apparatus for filtering liquids
WO2005118481A1 (en) 2004-05-28 2005-12-15 Brita Gmbh Filter cartridge and device for filtering liquids
EP1870150A1 (en) * 2006-06-23 2007-12-26 Unilever N.V. Filter and process to prepare the same
US20080110820A1 (en) 2004-06-30 2008-05-15 Elizabeth Louise Knipmeyer Gravity Flow Carbon Block Filter
US20080135489A1 (en) * 2006-09-20 2008-06-12 Omnipure Filter Company, Inc. Solid Profile Filters Comprising Activated Carbon Fiber Rods and Methods of Making and Using Same
US20090001011A1 (en) 2004-06-30 2009-01-01 Knipmeyer Elizabeth L Gravity flow filter
US20110203991A1 (en) * 2008-10-17 2011-08-25 Parthiv Ripudaman Dave Carbon block filter
US20120012515A1 (en) 2007-08-29 2012-01-19 Uv Corporation Filter assembly
RU2617775C1 (en) 2016-05-20 2017-04-26 Закрытое Акционерное Общество "Аквафор Продакшн" (Зао "Аквафор Продакшн") Filtering module of liquid purification device

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3538020A (en) * 1966-09-23 1970-11-03 Kata Mfg & Filtering Co The Fluid purification device containing a cartridge of polymer entrapped aggregate particles
RU2027474C1 (en) * 1992-08-21 1995-01-27 Электростальское научно-производственное объединение "Неорганика" Filtering element and method of its manufacture
RU2077491C1 (en) * 1995-08-29 1997-04-20 Электростальское научно-производственное объединение "Неорганика" Domestic water afterpurification filter
RU2091314C1 (en) * 1996-03-06 1997-09-27 Электростальское научно-производственное объединение "Неорганика" Filter for treating drinking water
RU14928U1 (en) * 2000-03-09 2000-09-10 Институт структурной макрокинетики и проблем материаловедения РАН FILTER FOR TREATMENT OF DRINKING WATER
RU2282494C2 (en) * 2004-04-08 2006-08-27 Общество с ограниченной ответственностью ООО "Аквафор" (ООО "Аквафор") Porous filter element (variations)
BR112014013542A8 (en) * 2011-12-08 2017-06-13 3M Innovative Properties Co decreased adhesion pressure vessel for bag filtration systems

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2919901A1 (en) 1979-05-17 1980-11-20 Itter Chemie Brita Geraete WATER PURIFICATION DEVICE
WO1998017582A1 (en) 1996-10-17 1998-04-30 Brita Gmbh A water treatment cartridge for use in domestic water treatment apparatus and domestic water treatment apparatus including such a cartridge
WO2005118482A1 (en) 2004-05-28 2005-12-15 Brita Gmbh Filter cartridge and device for filtering liquids
WO2005118104A1 (en) 2004-05-28 2005-12-15 Brita Gmbh Apparatus for filtering liquids
WO2005118481A1 (en) 2004-05-28 2005-12-15 Brita Gmbh Filter cartridge and device for filtering liquids
US20080110820A1 (en) 2004-06-30 2008-05-15 Elizabeth Louise Knipmeyer Gravity Flow Carbon Block Filter
US20090001011A1 (en) 2004-06-30 2009-01-01 Knipmeyer Elizabeth L Gravity flow filter
EP1870150A1 (en) * 2006-06-23 2007-12-26 Unilever N.V. Filter and process to prepare the same
US20080135489A1 (en) * 2006-09-20 2008-06-12 Omnipure Filter Company, Inc. Solid Profile Filters Comprising Activated Carbon Fiber Rods and Methods of Making and Using Same
US20120012515A1 (en) 2007-08-29 2012-01-19 Uv Corporation Filter assembly
US20110203991A1 (en) * 2008-10-17 2011-08-25 Parthiv Ripudaman Dave Carbon block filter
RU2617775C1 (en) 2016-05-20 2017-04-26 Закрытое Акционерное Общество "Аквафор Продакшн" (Зао "Аквафор Продакшн") Filtering module of liquid purification device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023135156A1 (en) * 2022-01-11 2023-07-20 Waterdrop Microdrink Gmbh Device for holding a filter pad for water purification

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