RO water is the result of the reverse osmosis process used for recycling, wastewater treatment and desalinisation. Used to remove contaminants from water by pushing it through a pressured, semi-permeable membrane, RO water can be used as a pure water supply in a number of industry sectors.
How Does Reverse Osmosis Work?
In normal osmosis, water would cross the membrane to produce a dilute of the concentrated solution. However, when water is treated by reverse osmosis, it is moved across the membrane, against the concentration gradient. This results in pure water and a concentrate of contaminants.
RO water treatment results in the movement of molecules from a region of higher concentration to a region of lower concentration. The semi-permeable membrane allows for the movement of water molecules, but not ions and larger molecules such as bacteria. As a result, treatment via reverse osmosis is ideal for the production of pure water for laboratory and commercial use.
An RO water system uses cross filtration rather than standard filtration, whereby contaminants are collected with the membrane or filter. As the feed water enters the pressured RO membrane, the water molecules pass through the semi-permeable membrane, discharging the containment through the reject steam. In some circumstances, this can be fed back through the RO system for further water recovery.
What Can Be Removed From RO Water?
Reverse osmosis water treatment systems can remove 99%+ of all inorganic contaminants, particles, ions, colloids, bacteria and pyrogens from feed water. Any contaminant with a molecular weight greater than 200 or a high ionic charge is more likely to be unable to pass through an RO water membrane. As a result, an RO system is not overly successful at removing gases, such as CO2,which is not highly ionized and has a very low molecular weight when in a solution. As reverse osmosis does not remove gases, the permeate water can often have a slightly lower than normal pH level. This is dependent on the CO2 levels in the feed water.
RO Water Treatment Solutions From ELGA
At ELGA Process water we provide a range or reverse osmosis systems for the purification of feed water. Designed specifically to produce pure water from 10 L/h to 30m3/h with a low footprint and reduce operation requirement, the SIRION™ models provide a compact solution for industrial and commercial use. We offer:
For more information or to discuss an RO water system for your business, contact us.
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