WO2008047393A1

WO2008047393A1 - An apparatus for treatment of drinking water, in particular for domestic use

Info

Publication number: WO2008047393A1
Application number: PCT/IT2006/000749
Authority: WO
Inventors: Giuliano Carapezzi
Original assignee: Enia Spa
Priority date: 2006-10-19
Filing date: 2006-10-19
Publication date: 2008-04-24
Also published as: EP1945582A1

Abstract

An apparatus for treatment of potable water, in particular for domestic use, comprises an inlet (2) for untreated potable water and a first filtration unit (6) operatively arranged downstream of the inlet (2) to separate any solid suspended particles from supplied potable water. The apparatus (1) also comprises a second filtration unit (15) operatively arranged downstream of the first filtration unit (6) for trapping;the bacterial loads present in water from the first filtration unit (6). The apparatus (1) comprises a third filtration unit (24) operatively arranged downstream of the first filtration unit (6) for separating organic and inorganic substances from water coming from the first filtration unit. The apparatus further comprises a dispenser (16) connected to the second and/or the third filtration unit (15, 24) to enable supply of sterile water from the second filtration unit (15) or of demineralised sterile water coming from the third filtration unit (24). The second and the third filtration unit (15, 24) are connected to one another and to the dispenser (16) for supplying sterile water with regulable mineralization. The apparatus also comprises a tapping device (31) connected to the third filtration unit (24) for dispensing ultramineralized waste water.

Description

An Apparatus for Treatment of Drinking Water, in particular for

Domestic Use.

Technical Field

The present invention relates to an apparatus for treatment of potable water, in particular for domestic use.

The present invention can be applied in any dwelling and/or in any public or private infrastructure, such as for instance a hospital structure, a commercial and/or an industrial structure. In particular the present invention is aimed at purifying potable water from a municipal water supply and/or any like water source.

Background Art

As is known, there exist apparatus for treatment of potable water designed to eliminate any organic and in general any suspended substances, to provide water having an optimal predetermined hardness, with values ranging approximately between 15 and 20 Frencji degrees; to reduce nitrates below the level of 50 ppm in accordance with the existing law standards (rule 98/83 CE) and preferably below 25 ppm, and to maintain sterility in water supply dispensers.

Among the various apparatus on the market, some prior art realisations are provided with a filtration group of a mechanical and/or active charcoal type designed to intercept and separate the suspended solid particles from the water, such as sand, clay and/or the like, as well as to eliminate any odours and/or tastes and chlorine which might be present in the municipal supply- water. The apparatus can also be provided with a membrane filtration unit, such as reverse osmosis membranes, aimed at physically separating the substances dissolved in potable water. The prior art apparatus can also be provided with an ultrafiltration unit which traps the bacteria loads and any similar organic substances in order to sterilize water.

An example of the above-mentioned apparatus is to be found in patent application EP05425909.8 by the same applicant, in which potable water from the municipal water supply initially flows through a mechanical and/or an active charcoal filtration unit before continuing, depending on the user's requirement, through the membrane filtration unit and then through the ultrafiltration unit, or through only the final filtration unit. In this way it is possible to tap three types of treated water from the dispenser outlet of the apparatus. A first type of treated water has the same properties as that from the municipal water supply, appropriately sterilized by the ultrafiltration unit. A second type of treated water coming from a double filtration in series process respectively performed by the membrane filtration unit and the ultrafiltration filtration unit, is purified of salts, minerals and organic substances. A third and last type of water, resulting from a first blending stage of water coming directly from the municipal water supply with water from the membrane filtration unit which has also undergone a second filtration stage in the ultrafiltration unit, is sterile and has salinity and mineralization values as set by the user according to need. As is known, the reverse osmosis membrane filtration unit produces a percentage of purified water which is normally consumed and a waste water percentage which is directly discharged into the waste water discharge network.

Although the prior art apparatus perform the purification and filtration of potable water of the municipal water supply, the Applicant has observed that they are not without drawbacks, and are susceptible to improvement in many aspects thereof mainly relating to their flexibility of use in a dwelling as well as to the possible dispensing of different types of treated potable water. In particular, the Applicant has noted that different types of water are necessary in a dwelling in order to fulfil different needs for different uses. In fact, in an apartment it is generally necessary to have different types of potable water, depending on various needs; demineralised water for some electrical appliances, such as a smoothing iron and/or the like; as well as highly mineralised water for plant irrigation. The different water types are also required in non-domestic structures, such as hospitals, galvanising industries, food industries and in other and various industrial applications. In connection with the above-cited requirements, the applicant has noted that the prior art apparatus for treating potable water are unable to fulfil all the needs in a relatively uncomplicated environment, such as a home, because of the limited properties of the water they dispense. An aim of the present invention is therefore to resolve the above mentioned problems.

Another aim of the invention is to provide a single apparatus which can treat incoming potable water in order to provide different types of water, each for a different use, with no waste water. A further aim of the invention is to provide an apparatus for dispensing sterile water, such as potable sterile water with regulable salinity and mineralization levels, sterile demineralised water, potable sterile water with a salt concentration equivalent to that from the municipal water supply and finally ultra-mineralized non-sterile water. Such types of water are each suitable for different uses in domestic, hospital and industrial structures. Another aim of the invention is to provide an apparatus equipped with safety devices for guaranteeing a reliable operation with consequent lower component stress which can reduce the negative effects attributable to the water hammer effect.

The specified technical objective and the specified aims are attained by an apparatus for treating potable water, in particular for domestic use, according to the claims that follow.

Disclosure of Invention

Further characteristics and advantages of the present invention will better result from the following detailed description that follows of a preferred embodiment of the present invention, which is illustrated by way of non- limiting example in the accompanying figure 1 of the drawing, which is a schematic view of a hydraulic circuit of the apparatus for treating potable water of the present invention.

With reference to the figure of the drawing, 1 denotes in its entirety an apparatus for treatment of potable water, in particular for domestic use. As can be seen in figure 1, the apparatus 1 comprises at least an inlet 2 of untreated potable water connectable at an end thereof to a municipal water supply 3 or any similar water source, and at another end thereof connected to a supply branch 4 in a corresponding hydraulic circuit 5. The supply branch 4 preferably extends between the inlet 2 and a first filtration unit 6 which is operatively arranged downstream of the inlet 2 for separating the solid suspended particles from the potable water of the municipal water supply 3, and at the same time for eliminating odours, tastes and chlorine (if present). The first filtration unit 6 advantageously comprises a first mechanical filter (not shown) having a sieve with pore diameter ranging between 50 and 20μ, preferably 20μ, a second mechanical filter (not shown) having a sieve with pore diameter ranging between 5 and 20μ, preferably 5μ, and a third active charcoal filter (not shown) all arranged in series. The third active charcoal filter should preferably be interposed between the others, respectively downstream of the first mechanical filter and upstream of the second mechanical sieve filter. As can be seen in the figure, a first one-way valve 7 and a first solenoid valve 8, which can be activated to stop and/or to allow potable water to pass along the supply branch 4, are located between the inlet 2 and the first filtration unit 6.

Downstream of the first filtration unit 6, the supply branch 4 comprises at an end thereof a branch point 9, from which a first dispensing branch 10 and a second dispensing branch 11 extend, preferably in parallel.

Advantageously the first dispensing branch 10 is provided, in series, with a second and a third one-way valve 12, 13 and a flow regulator 14. Downstream of the flow regulator 14 and therefore of the first filtration unit 6, the apparatus 1 comprises a second filtration unit 15 designed to intercept the bacterial loads in water coming from the first filtration unit 6 and to allow the passage of mineral salts previously contained in the potable water coming from the municipal water supply 3.

The second filtration unit 15 is preferably of the ultrafiltration type. The second filtration unit 15 is preferably designed to perform a molecular weight cut-off of between 5000 MW and 20000 MW in water flowing through the first dispensing branch 10. The first dispensing branch 10 is preferably connected, on an opposite side to the supply branch 4, to at least a dispenser 16 via a first on-off valve 17 and a fourth one-way valve 18.

As can be seen in the accompanying figure of the drawing, downstream of the branch point 9 the second dispensing branch 11 comprises a fifth one-way valve 19 operatively arranged upstream of a batching station 20 constituted by a reservoir 20a for anti-encrustation substances, such as polyphosphates for food use, which is connected to a respective pump 20b on the second dispensing branch. A pumping station 21 is arranged downstream of the batching station 20, which pumping station 21 preferably operates within a pressure range of between 5 and 10 bar, and a sixth and a seventh one-way valve 22, 23. The apparatus 1 also advantageously comprises a third filtration unit 24, located downstream of the first filtration unit 6, for separating organic substances, such as bacteria loads and viruses as well as inorganic substances, such as mineral salts, from water coming from the first filtration unit 6. The third filtration station 24, for facilitating the physical separation of the substances dissolved in water, is preferably of the reverse osmosis type with a large permeable surface, preferably above 2.0 m². In order to achieve a large osmotically permeable surface the third filtration unit 24 can comprise a pair of osmotic membranes 24a, 24b connected in parallel as shown in the drawing. The second dispensing branch 11 is provided downstream of the third filtration unit 24 with a pressure switch 25, a conductivity meter 26, a second on-off valve 28 and a sixth one-way valve 29.

The figure of the drawing shows the second dispensing branch 11 which, at an opposite side to the supply branch 4, is hydraulically connected to the dispenser 16 in order to permit the drawing-off of sterile demineralised water coming from the third filtration unit 24.

The apparatus 1 also comprises a third dispensing branch 30, hydraulically connected to the third filtration unit 24 and to at least one tapping device 31 for dispensing waste water coming from the third filtration unit. A second flow regulator 32 and an eighth one-way valve 33 are preferably arranged between the third filtration unit 24 and the tapping device 31. Once more with reference to figure 1, the apparatus 1 comprises a fourth dispensing branch 34 hydraulically connected at a side thereof to the first and the second dispensing branches 10, 11 respectively downstream of the second and the third filtration unit 15, 24, and at the other side thereof to the dispenser 16 for dispensing sterile water with optimal mineralization, which is achieved by blending water coming from the second filtration unit 15 with water coming from the third filtration unit 24. Still with reference to figure 1 a second solenoid valve 27 and a ninth one-way valve 38 are operatively arranged between the connecting device 36 and the dispenser 16. The. first 10, the second 11 and the fourth dispensing branches 34 are all hydraulically connectable to respectively a first dispenser 16a, a second dispenser 16b and a third dispenser 16c which are discrete and constitute different drawing-off points.

Each dispenser 16a, 16b, 16c comprises on its conduit a respective fourth filtration unit 39a, 39b, 39c, each comprising an ultra-filtration station to be arranged in very close proximity to the dispensing point. This is aimed at preventing a possible bacterial back-contamination of the dispensing branches 16a, 16b, 16c, on the part of external agents.

A respective one-way valve 40, 41, 42 is located downstream of each fourth filtration station 39a, 39b, 39c. More precisely, downstream of the fourth filtration station 39a there is a tenth one-way valve 40; downstream of the fourth filtration station 39b there is an eleventh one-way valve 41; and downstream of the fourth filtration station 39c there is a twelfth one-way valve 42. Finally, downstream of the tapping device 31, which terminates in a storage tank 44, there is a thirteenth one-way valve 43.

The opening of dispensers 16a and 16b is preferably performed by a solenoid valve, similar to the solenoid valve 27 located on the dispenser 16c and there-arranged in place of the corresponding on-off valves 17 and 38. The apparatus operates in the following way.

When the user wishes to draw sterile water with regulated salinity and mineralization coming from the third dispenser 16a, an electric control device will in succession open the first solenoid valve 27 and then the solenoid valve

8 and thereafter will activate the pumping station 21. After drawing off the sterile water with regulated salinity and mineralization, the solenoid valves 27 and 8 will be deactivated in reverse order, with the advantage of thus preventing water hammer on the apparatus components and promoting high apparatus reliability.

An alternative way of drawing off water involves dispensers 16a and 16b. Here the water dispensing involves opening the gate valves 17, 28 and the activation of the solenoid valves 27, 8 as already described. Also in this case the shutting-off process is done in reverse order.

The present invention solves the problems inherent in the prior art and achieves the set aims. Firstly the present invention object enables and guarantees the supply of four different types of treated water starting with potable water coming from the municipal supply. It should be noted that the present invention enables the best possible utilization of the characterising properties of water coming from the municipal supply as it guarantees sterile water supply with constant salinity as well as sterile water with regulable salinity and mineralization destined for daily consumption, as well as sterile and demineralised water for electrical appliances in general, and also ultra-saline, mineral-rich water which is also full of organic substances, ideal for plant irrigation.

It should be also considered that a supply branch interconnected between the third filtration unit and the tapping device permits the recovery of the percentage of ultramineralized water which is usually discharged into the waste water discharge network, thus achieving the purpose of an apparatus with no waste of water.

The presence of various filtration stations and in particular of the fourth ultrafiltration station makes it possible to use pipes as long as necessary for connecting the machine to the dispensing taps.

The presence of a differential pressure switch, a conductivity meter, solenoid valves, a one-way valve, ensure achievement of the aim of high apparatus reliability and safety during operation.

Claims

Claims.

1). An apparatus for treatment of potable water, in particular for domestic use, comprising: at least an inlet (2) of untreated potable water; a first filtration unit (6) operatively arranged downstream of the inlet (2) to separate at least one type of solid particles from incoming potable water; a second filtration unit (15) operatively arranged downstream of the first filtration unit (6) for trapping only the bacterial loads present in the water coming from the first filtration unit (6); a third filtration unit 24, operatively arranged downstream of the first filtration unit (6) to separate organic and inorganic substances from water coming from the second filtration unit (24); at least one dispenser (16) connected to the second and/or the third filtration unit (15, 24) to allow supply of sterile water from the second filtration unit

(15) or supply of sterile demineralised water from the third filtration unit (24), the second filtration unit (15) and the third filtration unit (24) being connected to one another and to the dispenser (16) in order to supply sterile water with regulable mineralization; at least one tapping device (31) connected to the third filtration unit (24) to enable the supply of ultra-mineralized waste water.

2). The apparatus of claim 1, wherein the tapping device (31) comprises at least a dispenser for tapping the ultramineralized waste water.

3). The apparatus of claim 1 or 2, wherein the third filtration unit (24) has no connection to a waste water discharge network.

4). The apparatus of one or more of the preceding claims, comprising: a first supply branch (10), hydraulically connected at an end thereof to the supply branch (4) downstream of the first filtration unit (6), and hydraulically connected at another end thereof to the at least one dispenser (16), the second filtration unit (15) being operatively arranged along the first supply branch

(10); a second supply branch (11), hydraulically connected at an end thereof to the supply branch (4) downstream of the first filtration unit (6), and at another end thereof to the at least one dispenser (16), the third filtration unit (24) being arranged along the second supply branch (11) and the first supply branch (10) and the second supply branch (11) being arranged in parallel; a third dispensing branch (30), hydraulically connected to the third filtration unit (24) and to the at least one tapping device (31), for supplying the waste water from the third filtration unit (24).

5). The apparatus of claim 4, further comprising a fourth supply branch (34) hydraulically connected at an end thereof to the first supply branch (10) and the second supply branch (11) respectively downstream of the second and the third filtration unit (15, 24) and at another end thereof to the at least one dispenser (16), for supplying a blend of water from the second filtration unit (15) and water from the third filtration unit (24).

6). The apparatus of claim 5, wherein at least one regulation device (35) is operatively arranged at a branch point of the first (10), the second (11) and the fourth supply branches (34).

7). The apparatus of one or more of claims from 1 to 3, wherein it comprises: a first dispensing branch (10) hydraulically connected at an end thereof to the supply branch (4) downstream of the first filtration unit (6), and at another end thereof, to a first dispenser (16a), the second filtration unit (15) being operatively arranged along the first dispensing branch (10); a second dispensing branch (11) hydraulically connected at an end thereof to the supply branch (4) downstream of the first filtration unit (6), and at another end thereof to a second dispenser (16b), the third filtration unit (24) being arranged along the second dispensing branch (11) and the first dispensing branch (10) and the second dispensing branch (11) being arranged in parallel; a third dispensing branch (30) hydraulically connected to the third filtration unit (24) and to the at least one tapping device (31) for dispensing the waste water coming from the third filtration unit (24); a fourth dispensing branch (34) hydraulically connected, at an end thereof, to the first dispensing branch (10) and the second dispensing branch (11) respectively downstream of the second and the third filtration unit (15, 24) and at another end thereof, to a third dispenser (16c), to supply a blend of water from the second filtration unit (15) and water from the third filtration unit (24).

8). The apparatus of claim 7, wherein at least one regulation device (35) is operatively arranged at a branch point of the first dispensing branch (10), the second dispensing branch (11) and the fourth dispensing branch (34).

9). The apparatus of claim 7, wherein the first dispenser (16a) comprises a fourth filtration station (29a) preferably constituted by an ultrafiltration station.

10). The apparatus of claim 7 wherein the second dispenser (16b) comprises a fourth filtration station (29b) preferably constituted by an ultrafiltration station.

11). The apparatus of claim 7 wherein thb third dispenser (16c) comprises a fourth filtration station (29c) preferably constituted by an ultrafiltration station. 12). The apparatus of any one of the preceding claims, wherein the first filtration unit comprises: a first mechanical sieve; a second mechanical sieve; and an active charcoal filter, the first and second mechanical sieves and the active charcoal filter being arranged in series, the active charcoal filter being interposed between the first and second mechanical sieves.

13). The apparatus of any one of the preceding claims, wherein the second filtration unit (15) is a molecular weight cut-off ultrafiltration unit.

14). The apparatus of any one of the preceding claims, wherein the third filtration unit (24) is a membrane filtration unit, preferably comprising at least two osmotic membranes (24a, 24b) connected in parallel.

15). The apparatus of any one of the preceding claims, wherein the inlet (2) is intercepted by a first solenoid valve (8), preferably arranged upstream of the first filtration unit (6), and the dispenser (16) is intercepted by a second solenoid valve (27), the first and the second solenoid valves (8, 27) being activated in succession by electric means.