We are all aware of the environmental problem reality related to water. In spite of this, not much is done to limit its waste and bad use, probably caused by consolidated domestic habits and lack of information on how and what to do to have more respect for this precious resource.

Up to few years ago, the common sensation was that water was an inexhaustible and non-modifiable source. The recent atmospheric vicissitudes and the greater contemporary ecological consciousness, made us understand that this natural good should be used with greater attention and with respect.

The water economy problem is mainly felt in those parts of Italy (particularly the islands) where the shortage is historical and where the provisioning costs are heavy both under the social and the family profile.
Every day in Italy we use 200 litres of water per person for domestic uses. Of this amount, 28%, equal to 56 litres, is consumed through the WC drainage, 36% through other bathroom fittings (shower, washbasin…), the remaining amount for household machines.

The Save Water System (SWS) recycles water from the bathroom fittings in order to reuse it, after purifying it by using exclusively mechanical systems, in the WC flush.

SAVE WATER SYSTEM mod. V1
The system provides for the collection of shower and washbasin drainage water in a tank located under the shower tray. When the WC flush is used, water refilling is made by drawing water from the collection tank through an electropump, and at the same time, by closing the usual flush supply by means of an electric valve. In case the recycle water is insufficient, the valve will automatically open and the WC tank will be filled with circuit water.

The V1 model is essentially divided in a simple tank with its own mechanic systems of decantion and an electro-hydraulic part, removable, external to the shower tray, in order to allow a simple assemblage and maintenance simply lifting two tiles glued to a lid.

The domestic water is stored in the collecting tank 1, located under the shower tray 11. Water is collected both directly from the shower drainage with the upper shower tray, and through the drainage of other uses (basin, bidet…) 100. The shower deriving water is already without “heavy dirt” (hairs…) because passes through its normal filter; it will pass only the “light dirt” (foam…). Water deriving from 100 drains directly in the decantation chamber 21, releasing the heavy dirt (hairs…) in the small filter-tank 2 removable for the odd cleaning, and overflows through the main weir 3 in the collection tank 1. When water reaches the wanted limit (8-20 cm) overflows in the small overflow-tank 4 and gets out directly to the drainage 101. Water of tank 1 containing only light dirt, i.e. floating, passes under the main weir 5 in the part of the tank 20 where the pump 7 is positioned, but leaving on the other side all the light dirt which will tend to get out through the overflow 4, little by little that the arriving-waters exceed the limit.

When the WC-flush button connected with 103 is activated, the normal circulating water arrives immediately through 104. With the water passage, instantly the relay 6 flow-sensor closes the connection, operating in this way the closing of the alimentation valve 8 and activating at the same time the pump 7. The floating relay 9 allows to control that there is enough water in tank 1 and 20 and in negative case does not allow the closing of valve 8 (always open) neither of pump 7. The not return valve 10 avoids that the water deriving from 104 enters in 1 but goes exclusively in 103.

In a form of realization all the operative elements of the water-flow are located in the three chambers 20, 21, 22. The small filter-tank 2 is located in chamber 21 separated from chamber 1 by weir 3. Flow-sensor 6 and valve 8 are located in chamber 22, the only one that is not submerged of water. Pump 7 and level-sensor 9 are located in chamber 20 where weir 5 permits the flow only of clean water.

In the normal fully functioning, the WC flush water is supplied by pump 7. When WC-flush closes independently its own entrance, because already full, water stops flowing from 103 and so the flow-sensor 6 opens again the contact stopping the pump and disconnecting the valve 8.

In case of maintenance it will be possible to open the upper lid that covers the external part of the shower tray 20, 21, 22 and that contains all the functioning parts. It will also be possible to take out the small tank 2 in order to clean the dirt accumulation.

ADVANTAGES
To fully understand the system advantages, consider that, in national terms, up to 1.200.000.000 (onebilliontwohundredthousand) cubic meters of water are wasted every year in the WC - equal to the amount of water contained in the Garda Lake.
Water wasted in Italy in the WC each year 1.200.000.000 m3
WC water waste by each person per day 56 litres
Considering that an average family of 3 persons consumes 220 m3 of water per year, which gives a cost in the family budget, that ranges depending on the region, from 250 to 500 € (provisioning cost plus removal cost); the 28% of this is wasted in the WC. From the Italian average consumption data, it is possible to presume the advantages in the use of Save Water System that may be estimated in 40/litres per person per day (the 70% of the real waste in the WC).

Annual saving of water consumption for a family 80-100 €
Annual saving in electric energy to pump WC water in the houses 200.000.000 €
Furthermore, also the following advantages shall be indicated: reduction of the drainage water ducts diameter, reduction of the water-supply ships sent to the islands for provisioning, reduced river pollution, reduction of provisioning difficulty in the cities subjected to water shortage.

Dr. ing. Settimo Martinello
4 EMME Service Spa
settimo.martinello@4emme.it