Reverse osmosis is a well-tried and tested technology for the production of desalinated water for use as both drinking and industrial process water. WABAG supplies RO plants in differing sizes for various types of raw water such as sea and brackish water and industrial effluent. Major attention is paid to economic factors such as chemical consumption, energy recovery, membrane durability and process automation. The result is optimum quality drinking or process water at minimum cost. On the the basis of our experience with plants of varying sizes, we offer economically advantageous and technically proven solutions for every application.
Osmosis is a natural phenomenon, which occurs in all living cells as a control on the water balance. In order to equalise solution strength, water diffuses through a semi-permeable membrane towards the higher concentration. The ultimate height difference between the water columns on both sides of the membrane is referred to as osmotic pressure.
The application of pressure greater than the osmotic pressure of a liquid reverses the water flow direction over the membrane. In reverse osmosis, a pre-treated fluid is pressurized to a level above that of the osmotic pressure and then additional pressure is added to raise productivity. This results in a water flow over the membrane (permeate flow) with a salt content below that of the raw water. In general, permeate is obtained at near atmospheric pressure and with a lower salt content, while the feed solution remains on the other side of the membrane and has an increased salt content. This concentrated solution is disposed of as brine.
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