ITRM20100334A1 - WATER ULTRAFILTRATION DEVICE. - Google Patents

Description

â € œWATER ULTRAFILTRATION DEVICEâ €

DESCRIPTION

Technical sector

The present invention refers to a mains water treatment device, and in particular to a water filtration device, ideal for domestic use, which allows drinking purified water and cooking using it. Known technique

It is known that the water supplied by the aqueduct, although drinkable and controlled, can often contain unpleasant doses of chlorine, chemical traces of rust, or sand (brought from the old pipes) as well as infiltrations and organic impurities.

Therefore, over time various systems / devices have been developed to obtain purified mains water, usable for domestic use, by mounting the devices downstream of the cold water supply pipe and upstream of the simple tap or water mixer. hot / cold.

However, each of these known devices has some drawbacks for which none of them can be considered optimal from every point of view.

A first method used is that which makes use of reverse osmosis. The advantage of this technique is to block bacteria and viruses as well as endotoxins. However, reverse osmosis devices have many drawbacks. First of all they must be powered by electricity and the water they supply is essentially distilled water without mineral salts, as the latter are blocked by the device. Furthermore, they waste a considerable amount of mains water, require considerable maintenance, and there is also the need to have a greater flow of filtered water, which they are unable to make available.

Osmosis devices with accumulation tank and UV lamp have the further disadvantage of not blocking endotoxins as well as having an increase in the consumption of electricity to power the UV lamp and greater maintenance of the whole system (pump , lamp, float valve, etc.).

The activated carbon devices leave the mineral salts in the water and do not require an electric power supply. Furthermore, they do not waste water, they can have high flow rates of filtered water, they can enjoy poor maintenance, but unfortunately they do not block the harmful â € œbiological matterâ € which includes bacteria, viruses, endotoxins. This constitutes a significant disadvantage as the risk of legionella and so on is known.

On the other hand, if activated carbon devices combined with a UV ray lamp are used to eliminate viruses and bacteria, there will be a consumption of electricity for the power supply of the UV lamp, greater maintenance, greater of filtered and purified water, and above all the dangerous endotoxins will not be eliminated.

Therefore, there is currently a need to provide a mains water treatment device, in particular consisting of a water filtration device, which is ideal for domestic use, allowing it to drink purified water and to cook using the same water thanks to the considerable flow of filtered water that comes out of the device.

In particular, the purposes of the present invention are the following:

make a filtration device that

- blocks sediments, chemicals, bacteria, viruses, and endotoxins;

- does not block mineral salts;

- it does not need an electric power supply;

- do not waste water (common osmosis systems considerably reduce the mineral salts essential for our health and throw away about 4 liters of water every 5 liters);

- it is small and light so as not to occupy any space destined for other needs (the solutions on the market partially or entirely occupy the sink to the detriment of the indispensable numerous waste bins now required by the Municipalities for the management of household waste);

- has a large flow (flow rate) of filtered water (for example 240 liters / hour of water delivered against the approximately 30 liters / hour of osmosis systems);

- is easy to install;

- has a very low maintenance, possibly without requiring the intervention of a technician to carry out maintenance (the device object of the present invention can operate for example also for 12-24 months, or 10000 liters, without requiring maintenance and losing its properties ).

Therefore, thanks to the present invention it will be possible to obtain filtered water, bacteriologically pure, to drink or recommended for cooking, which improves the taste of food and is suitable for preparing baby food, tea, coffee, infusions, cosmetics, humidifiers. air, aquariums, etc.

Furthermore, the device will serve to supply always fresh, non-stagnant water (unlike other filtration systems with accumulation or bottles).

Furthermore, costs will be greatly reduced compared to existing devices thanks to the use of particular components, of convenient cost, in the device object of the present invention. The problems of space, storage and disposal of the empty water bottles otherwise necessary for drinking and / or cooking, etc. will also be solved.

Description of the invention

The objects of the invention are achieved by means of a particular combination of filters, arranged according to a precise sequence.

The first filter, or first stage of the mains water ultrafiltration device according to the present invention, is constituted by a sediment filter, already known per se. The sediment filter works by removing the suspended solids and the various sediments contained within the water of the house, such as: rust, earth, organic substances, and various encrustations present in the aqueducts.

The preferred degree of filtration for this filter is, by way of example, around 5 microns. Preferably, the autonomy of this filter will be 10000 liters, corresponding (in the case of a normal consumption of domestic water) to a total period of water consumption of 12-24 months.

The second filter, or second stage (placed in series with the first stage) of the mains water ultrafiltration device according to the present invention, is a carbon block filter designed for the absorption of the chemical components present in the water, such as : chlorine, disinfectants, herbicides (atrazine, pesticides, herbicides, and chemical fertilizers used in agriculture). It is a filter consisting of a particular mixture of activated carbon and molecular polymers, pressed and sintered so as to result in a homogeneous block, very resistant, with remarkable and important absorption capacities.

These characteristics allow the carbon block filter to:

- block most of the chemical and VOC (volatile organic) pollutants present in the water such as chlorine, nitrates, organic substances, pesticides, herbicides, chlorinated solvents, atrazine, molinate, benzene, trihalomethanes, etc.

- eliminate / reduce unpleasant tastes and odors

The special chemical-physical manufacturing process of the filter allows to obtain smooth external filtration surfaces, which are able to retain the solid impurities present in the water and to be washable, so as to easily eliminate the impurities retained in the water. And to restore the normal flow of water. Unlike traditional activated carbon filters (granular), it does not release particles and does not give rise to channeling and bypass phenomena.

The degree of filtration (porosity) of said second filter is preferably around 5 microns. Its autonomy is also preferably 10,000 liters, equal to a normal period of water consumption in the home of 12-24 months.

The heart of the invention is the third (ultrafiltration) or third filter stage, located downstream of the second / filter stage. The third filter includes a membrane for ultrafiltration, with hollow fiber and already used only in the biomedical field, and for low pressures, lower than those of the present use.

The physical structure of the membrane forms an effective barrier capable of retaining tiny organic substances, preferably with a molecular weight greater than 15000 daltons, i.e. larger than 0.005 microns. This means guaranteeing total protection from bacteria, viruses (eg legionella), and endotoxins. The result of filtration is therefore an ultrapure water which however (unlike the osmosis technique) does not block the mineral salts.

The autonomy of this filter will also exceed 10,000 liters.

It should be emphasized that, according to the present invention, a pressure reducer limited to 3 bar is inserted upstream of the first filter (the one for sediments) in order to reduce the pressure of the mains water which would otherwise damage the three filters. and especially the ultrafiltration membrane of the third filter. One material for making the ultrafiltration membrane is polysulfone, a type of ultrafiltration membrane currently used in dialysis and washing of burn patients. However, given the very different field of application of the present invention, to demonstrate the validity of the device of the invention it was essential to carry out very precise tests (see below). These tests have unequivocally confirmed the effectiveness of the present invention. Indeed, it was not clear a priori whether at the pressures of use of the mains water (of the order of a few bars), it was possible to make a suitable filter. Surprisingly, as shown by the tests, the invention has made it possible to overcome all the disadvantages of the prior art.

Brief description of the figures

The present invention will now be illustrated in more detail with reference to the drawings, provided by way of non-limiting and non-binding example only.

In the drawings:

FIGURE 1 is an illustrative diagram of the device of the invention for ultrafiltration of mains water, limited to the three filters, which constitute the fundamental part;

FIGURE 2 is a perspective view of the open box, preferably in AISI 304 stainless steel, which forms the outside of the device and encloses the aforementioned filters.

Detailed description of some favorite creations

Fig. 1 shows the three filters which form the basis of the device of the present invention. 1 indicates the inlet (aqueduct) of the sediment filter, while 2 indicates the exit from the third filtration stage including the ultrafiltration membrane. The numbers 3, 4 and 5 indicate the sediment filter, the carbon block filter, and the ultrafiltration membrane respectively. Each of these filters is arranged in a closed tubular casing (not better shown) which can be inserted in one of the respective semi-cylindrical seats 6, 7, 8 of Fig. 2, which are formed by a single filter support bracket. In this embodiment, the box 11 which encloses the components of the device has a lid 9 hinged on a base 10, which can be closed with a screw placed on the lid 9 (not visible in Fig. 2). The inlet 1 and outlet 2 pass through one of the four side walls of the base 10 of the stainless steel box 11 in correspondence with the bulkhead fittings (this is not shown in Fig.2).

The pressure reducer mounted before the sediment filter 3 (first stage) is not shown in Figure 1.

Numbers 12 and 13 indicate flexible tubes for the passage of water from one stage to another: stage 1 â † 'stage 2 (flexible tube 12), stage 2 â †' stage 3 (flexible tube 13 ).

Not wanting to go too far into the construction details, which are not even shown, essentially flexible tubes are also present between the two bulkhead fittings placed on the box 11 (not shown) and the relative housings of the filters 3 and 5 respectively.

The device of the present invention is designed to be easily installed under any type of furniture. The installation must be carried out by qualified personnel as required by the regulations in force, in particular those of the European Union countries.

The tubes will preferably be made of plastic resins for food use. The dimensions (section) of the tubes that are inserted into the respective fittings on the filters must be perfectly adapted to the fittings themselves, as even small differences in the section of the tubes can compromise the tightness of the fittings.

The installation procedure of the device object of the present invention provides:

- the connection of the tap with the outlet 2 of the device of the invention;

- the connection of the water mains (by means of a shut-off valve) with the inlet of the device of the invention.

After installation, it is preferable to wash the filters by keeping the mixer tap open for at least 5 minutes. The flow may initially be slow as well as the color of the water a little dark.

The device of the present invention normally requires practically no maintenance (except for the need for sanitization; the case of possible loss of an O-ring; the rupture of the tubes, or other). Therefore, apart from the easy periodic replacement of the filters, to be carried out - as mentioned above - normally every 12-24 months from installation, the device works perfectly â € œautonomousâ €.

Furthermore, the device does not require electricity for its operation. The replacement of the filters can also take place without the intervention of a specialized technician, according to the following procedure:

a) close the supply tap;

b) release the pressure from the dispensing tap;

c) open the device of the invention (by unscrewing the screw located in the center of the cover or, for the EPP version, by simply removing the cover by levering in the appropriate slots);

d) disconnect the filters from the tubes (by removing the special safety clips); e) connect the new filters to the tubes (replacing the appropriate safety clips); f) reopen the previously closed taps;

g) verify the possible existence of losses;

h) close the device of the present invention (by tightening the screw located in the center of the cover in the case of the stainless steel version).

To ensure tightness, O-rings or similar will also be provided.

The flow rate of the device can also exceed 300-350 liters / hour. The water fed to the device must be drinking water with a pressure preferably not less than 2 bar.

The present invention has been illustrated purely by way of non-limiting or binding example. Obviously, the experts in the field will be able to carry out modifications or devise variants without going out of the scope of protection that rightly belongs to the invention.

For example, the device of the present invention could be equipped with a (small) water meter, in particular such as to trigger an alarm when 10,000 liters are reached, or another value in liters (possibly settable), after the which you need to change the filters.

Two or more devices of the present invention could also be placed in cascade, with by-pass cocks for the first, second, third, â € ¦, nth device, so as to make it necessary to replace the filters and / or sanitization even after several years.

This would further reduce maintenance. It all obviously depends on the space available for installation. In any case, the device of the present invention is very compact, and in one of its particular, non-binding embodiments, its dimensions are: 48 x 30 x 9 cm. The results of the tests carried out with the device of the present invention are reported below.

Result of bacterial retention tests carried out on MediSulfone <®> UF ultrafiltration membrane.

Procedure: The test suspension containing bacteria of the genus Pseudomonas and Legionella in a concentration equal to 10 <10> germs / 1000 ml (corresponding to 10 <7> bacteria / cm <2> of filtration area) was filtered with filters of the device in question. The filtrate obtained was concentrated by membrane filtration (from 0.22 µm for Legionella and from 0.45 µm for Pseudomonas), the membrane was deposited directly on the selective medium and incubated for at least 48 hours at 30 ° C (Pseudomonas) and at least 96 hours at 36 ° C (Legionella). The efficiency of the device filters in retaining the bacteria under study was expressed in terms of the Logarithmic Reduction Value (VRL) of the filter:

VRL = Log10 (number of bacteria in the challenge / number of bacteria in the filtrate) Results:

Sample Date Bacterium Volume CFU / 1000 CFU / 1000

suspension ml in ml in the VRL Filtered suspension test Pass / Fail Pseudomonas

1 03/07/09 aeruginosa 1000 ml 1.6 x 10 <10> 6 9.4 Past ATCC 27853

Pseudomonas

2 14/07/09 aeruginosa 1000 ml 2.5 x 10 <10> 11 9.3 Past ATCC 27853

Legionella

3 17/07/09 pneumophila 1000 ml 2.6 x 10 <10> 15 9.2 Past ATCC 33152

Legionella

4 17/07/09 bozemanae 1000 ml 2,5 x 10 <10> <1> 10 Past ATCC 33217

UFC: Colony Forming Units

The results obtained show that the filters on the device have a probability of

bacterial retention greater than 99.9999999% for Legionella pneumophila and P.

aeruginosa and above 99.99999999% for Legionella bozemanae.

Claims (12)

CLAIMS 1. Mains water ultrafiltration device, characterized by the fact of comprising three filters (3, 4, 5) connected to each other (12, 13) as well as connectable through an outlet (2) and an inlet (1 ) to a tap / mixer and respectively to the cold water supply pipe, called three filters (3, 4, 5) including a first filter (3) for sediments, a second carbon block filter (4) for chemicals , for example atrazine, herbicides, pesticides, lead, and an ultrafiltration membrane (5), or third filter (5), to block bacteria, viruses and endotoxins, the ultrafiltration device not being powered by electricity to perform its function ultrafiltration of the mains water that reaches the device at a pressure between about 2 and about 7 bar, and said first filter (3) for sediments, which corresponds to the first stage of the ultrafiltration device, being equipped with a pressure regulator , such as to guarantee a flow o acceptable water supply for domestic applications. 2. Network water ultrafiltration device according to claim 1, characterized in that said pressure regulator constitutes a pressure reducer to reduce the pressure to about 3 bar. 3. Network water ultrafiltration device according to claim 1 or 2 characterized in that said carbon block filter (4) is in particular constituted by a mixture of activated carbon and molecular polymers, pressed and sintered to form a homogeneous block which it does not release particles and does not give rise to so-called channeling or bypass phenomena. Network water ultrafiltration device according to claim 3, characterized in that the external filtration surfaces of the carbon block filter (4) are smooth. 5. Network water ultrafiltration device according to any one of the preceding claims, characterized in that the ultrafiltration membrane has a filtration degree of about 0.005 microns. 6. Network water ultrafiltration device according to any one of the preceding claims, characterized in that the membrane is a hollow fiber membrane used in the biomedical field. 7. Network water ultrafiltration device according to any one of the preceding claims, characterized in that the membrane is constituted by polysulfone. Network water ultrafiltration device according to any one of the preceding claims, characterized in that the carbon block filter (4) has a filtration degree of about 5 microns. Network water ultrafiltration device according to any one of the preceding claims, characterized in that the sediment device has a filtration degree of about 5 microns. 10. Network water ultrafiltration device according to any one of the preceding claims, characterized in that it comprises: - an external protective body (11), preferably a stainless steel or expanded polypropylene (EPP) box; - bulkhead fittings on said external body (11), for the inlet (1) where the water to be filtered passes and respectively the outlet (2) where the already filtered water passes; - housings for said three filters (3, 4, 5) and a relative bracket with three seats (6, 7, 8) of the respective filters; - detachable flexible tubes, connected respectively: a) between the inlet (1) and the pressure regulator of the first sediment filter (3); b) between the outlet (2) and the third filter (3); c) respectively (12) between the first filter (3) and the second filter (4), and (13) between the second filter (4) and the third filter (5); d) safety means, for example clips, of the removable type, detachable before replacing the filters (3, 4, 5); e) connections between said tubes and said filters (3, 4, 5); f) sealing means, for example O-rings; g) means for closing and opening the external body (11), for example, in the case of stainless steel, consisting of a screw placed centrally on the stainless steel box (11). 11. Network water ultrafiltration device, according to any one of the preceding claims, characterized by the fact of comprising a water meter with a signaling device to signal the achievement of the maximum quantity of filtered water such as to make it necessary to replace the filters. 12. System consisting of several devices according to any one of the preceding claims, connected to each other and respectively to the mixer and to the cold water supply pipe, and equipped with ducts and bypass valves between the various devices, to operate even only one filter at a time and thus extend the maintenance-free period P to a maximum period of nxP, where n is the number of devices.