Reverse osmosis plants(RO Plant) require pre-treatment to minimize energy requirements. These include softening, dechlorination, and anti-silent treatment of the water. High levels of pressure send the water through a semipermeable membrane, which retains all contaminants but lets pure water pass through.Reverse Osmosis plant(RO Plant) is a common process to purify or desalinate contaminated water by forcing water through a membrane. Water produced by RO Plant may be used for a variety of purposes, including desalination, wastewater treatment, concentration of contaminants, and the reclamation of dissolved minerals.RO Plants are used to remove salts and other inorganic substance from the water.