TECHNICAL FEATURES
Direct Osmosis is a phenomenon that happens normally in nature, for instance in the cells of all
living organisms, and it is the process where with two solutions of different concentration divided
by a semi-permeable membrane (that is allowing water but no salts to go through), the more
diluted solution tends to move naturally towards the more concentrated solution till the
concentration of the two solutions becomes the same; the pressure created on the membrane
because of this flow is called Osmotic Pressure.
Exploiting this principle, it is possible to reverse the process by applying a similar
but adverse pressure to the concentrated solution to obtain from it a solution of
lower concentration: this process is called Reverse Osmosis.
The osmotic membrane carrying out the best filtering level achievable, behaves like a barrier not
only against the salts and inorganic substances making up the saline composition of the water,
but also against organic substances such as pesticides, pyrogens, viruses and bacteria; a nominal
rejection (reduction capacity) of 100% can be reached with bacteria.
The bigger the difference between the pressure applied and the osmotic pressure, the bigger is
the quantity of water produced per unit of surface of semi-permeable membrane.
The supply pressure required varies according to the type of water and salinity to be treated
(therefore according to the relative osmotic pressure to overcome):
- System water: from 2-3 up to 18-20 bar
- Brackish water: from 7-8 up to 34-40 bar
- Sea water: from 50-55 up to 70-85 bar
The most suitable membrane (as far as type and dimension are concerned) must be chosen for
each system, following a modular criterion, so that the chosen membrane is arranged following
a system of elements in series and in parallel.
A reverse osmosis membrane cannot remove 100% of salts (even if today 99.5% can be achieved)
and cannot treat 100% of the supplied solution, therefore a reverse osmosis system has a Supply,
a Product (also called Permeate) and a Discharge (also called Reject or Concentrate).
These days reverse osmosis technology has undergone such quick development that compact,
simple, versatile systems are achieved, characterized by constant output, both in terms of water
produced and its quality.
No civil or industrial business exists that can do without specifically treated water; from the water
for boilers that must have precise chemical-physical specifications to process water (chemical
and pharmaceutical, food, drink industries, etc.) that must adhere to stringent production
requirements, the possibilities for use of the reverse osmosis process can be considered endless.
In this sector too, reverse osmosis technology has conquered a leading role thanks to its
adaptability, cost-effectiveness and running simplicity.
The RO reverse osmosis systems by ATLAS FILTRI use very high quality components
and are designed to meet the requirements of any customer, on the basis of the
analysis results of the origin water; apart from a standard range, on request ATLAS
FILTRI can provide specific solutions.
Every installation can be fitted with pre- and post-treatment systems; ATLAS FILTRI
can boast a wide experience in the water treatment and filtering sector, with a wide
range of items and equipment for both the domestic/civil and industrial sectors.
CERTIFICATIONS
The products are tested and certified under the most stringent
procedures worldwide, in compliance with DM 25 (Italy) and
with the sanitary certification EAC/Ghostreghistrazia
(Russia).
338 | water treatment systems
- Domestic uses: cleaning-up of drinking water,
elimination of any smells and tastes connected to the
presence of chlorine or chlorine derivatives,
pesticides, insecticides, fungicides, heavy metals,
micro-organisms, strong reduction in salt content.
- Technical uses: in all processes where demineralized
water is used, production of drinking water from wells
or sources with values within their operational
conditions.
NOTES: The system is suitable to treat water with
certain chemical-physical and microbiological
characteristics that might require pre-treatments,
so it’s always necessary to have a complete
analysis of the water to be treated.
SYMBOLS LEGEND
For domestic use
For technical and
industrial use