Operation principle

The SIREG units called HYDROS®, apply the reverse osmosis system in order to demineralize , to desalinate and to purify the water. By exploiting the characteristics of special semi-permeables membranes , without adding any chemicals, they totally remove from the water organic pollutants (bacteria, virus , ect) inorganic pollutants (herbicides, pesticides ect.) and , according to the requirements, up to 98 % of salts in solution. The water entering the purifier is subjected to a preliminary treatment to remove solid particles (sand, rust, ect.). The treatment is performed with two or more forced filtration modules. The water out from the filtration section is conveyed, only by means of the network pressure or by means of a pump, to reverse osmosis membranes in which the purification or demineralization treatment takes place. Two flows are conveyed from the reverse osmosis modules:

• A purified or demineralized water flow, called permeate, for different uses.
• A concentrated water flow to convey to the discharge or, according to the plant configuration, to the use, to reconvey totally or partially to the purification cycle.

Reverse osmosis

The osmosis is a natural phenomenon that occurs when water flows from a dilute saline solution, through a semipermeable membrane, into an higher concentrate saline solution until the equilibrium is reached. The pressure which forces the water through the membrane is called osmotic pressure. If a pressure higher than the osmotic pressure, is applied to the compartment with the higher concentration salt solution, the phenomenon is reversed: the water molecules pass through the membrane, while the salts, organic molecules and almost the whole microbial charge are rejected. The result is a concentrated solution in a compartment and the purified water in the other one. This phenomenon is called reverse osmosis.