Reverse Osmosis is a technology that is used to remove a large majority of contaminants from water by pushing the water under pressure through a semi-permeable membrane.
How does reverse osmosis work?
Reverse Osmosis works by using pressure on the feed side of the RO which forces the water across the semi-permeable RO membrane, leaving almost all (around 95% to 99%) of dissolved salts behind in the reject stream. The amount of pressure required depends on the salt concentration of the feed water. The more concentrated the feed water, the more pressure is required to overcome the osmotic pressure.
The purified water that passed through the RO membrane, is called permeate water. The water stream that carries the concentrated contaminants that did not pass through the RO membrane is called the reject.
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