The F-caff module improves the quality of water significantly thanks to the nanofiltration tecnology.
The nanofiltration is based on the reverse osmosis principle.
Osmosis is a natural phenomenon which occurs between 2 solutions with different concentration, separated by a membrane, permeable to water but not to salts. The pressure developing in the membrane is called osmotic pressure.
By applying a pressure at least equal and opposite to the osmotic pressure, the process is reversed (reverse osmosis) and water with very low salinity is produced from a higher concentration water.
WHAT OTHERS DO
The Calcium Carbonate (CaCO3) creates scale deposit precipitating due to heat or evaporation. Ionic exchange resins are used in the water softening process and exchange the Calcium and Magnesium of the water with the Sodium contained in it.
By using an excess of Sodium as Sodium Chloride, the reaction is reversed, the Calcium is eliminated and the resin is regenerated.
The water treated in this way will no longer contain Calcium Carbonate, the rest of the mineral salt composition of the water remains unaffected.
Recently new cationic resins (weak) have been introduced in form of Hydrogen. These remove the hardness due to the bicarbonates and the regeneration occurs only with the addition of a strong acid, such as HCI. In case of bars or home use the resins can not be regenerated, therefore, once exhausted they are trashed. Even in this case some residual hardness, although in lower concentration, remains as this depends on the chemical composition of the water.