Chemical and Physical Treatments, what to do

The water, whether it comes from the aqueduct,

either from wellspring stratum, contains a variety

of minerals. In particular the carbonates of calcium

and magnesium, also called salts of hardness. The

amount of such salts dissolved in water determines

its hardness, measured in parts per million (ppm)

of calcium carbonate, or more commonly in French

degrees (°f), where 10 ppm of CaCO

3

equivalent

to 1 °f. The salts of calcium and magnesium, with

heat are transformed into carbonates and precipi-

tate forming the incrustation commonly called lime-

stone. This happens already at around 35 - 40 °C.

The limestone is a very bad conductor of heat and

therefore an excellent thermal insulator, this means

that where there are deposits will be required more

and more electrical or thermal energy to heat the

water at the desired temperature. The scaling in pi-

pes then decrease the useful space for the transit of

water and may also cause a punctiform corrosion,

the worst one because it obliges the replacement

or repair of pipes, and bring also obstruction da-

mages caused to valves, pumps, mixers, shower

heads, etc. The solution to all these problems is the

reduction of hardness, this means the softening or

water conditioning as prescribed by DM 26/2015.

For many years, there is a widespread technique

to add specific chemicals to drinking water for the

protection of water systems against corrosion and

limescale , among them has caught the use of

proportional dosing of polyphosphate. In fact, the

polyphosphate is combined with the hardness of

the water and prevents the precipitation (in par-

ticular when the water is heated in boilers, water

heaters , washing machines, dishwashers, etc.),

thus avoiding the formation of scale, which de-

termine the loss of efficiency of heating systems

and high energy consumption. The polyphosphate

also professes a protective function by exerting an

anticorrosion action. The dosage of polyphospha-

te diffused on the market in various forms inclu-

ding powder, crystals, liquid refills, it is generally

made with two types of systems: proportional and

non-proportional.

The quantity of polyphosphates dosed into the wa-

ter from a non-proportional system does not de-

pend from the flow or from the consumption. On

the contrary, proportional systems dose a quantity

of polyphosphates into the water proportional to

the flow and consumption, being particularly indi-

cated for the treatment of water intended for human

consumption. In particular, systems with polypho-

sphate powder , such as our WL- DOSP 5 - 6 - 7

(Fig. 2). Systems with polyphosphate liquid are real

pumping systems that charge the additive winning

the pressure water net.

WL-doSP Id2

1

WL-doSP Id3

WL-doSP Id4

2

Figure 1 - 2

Examples of polyphosphate powder and refil dispensers

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