The entire reverse osmosis system consists of high-pressure pumps, reverse osmosis membranes, pressure vessels, as well as corresponding instruments, meters, valves, racks, pipelines, and fittings. Reverse osmosis membrane is a new type of separation membrane driven by pressure. Under pressure, water molecules in the solution pass through the membrane, while other molecules, ions, bacteria, viruses, etc. are intercepted, thus achieving the purpose of purifying water. The pore size of reverse osmosis membrane is less than 1nm, which can effectively remove divalent ions, and the removal rate of monovalent ions can reach 95-99%; The removal rate of low molecular weight organic compounds can reach 100%; Can effectively remove pathogenic microorganisms, various bacteria, and viruses. Make the effluent Ames mutagenicity test negative. The two-stage reverse osmosis system can remove over 99% of minerals, bacteria, viruses, pyrogens, and bacterial endotoxins from raw water. Compared with cation exchange beds, reverse osmosis devices have the advantages of simple equipment operation, no acid-base regeneration pollution, and low operating costs, which have gradually replaced cation exchange beds