Reverse osmosis (RO) membrane is a polyamide composite membrane which is composed by permeating liquid core columns, isolated networks, film, membrane and crust. Its filter aperture is only 0.0001 microns, the operating pressure is between 0.6-1.5 Map, and the desalting rate is high to 99%, so the chemical ions, bacteria, viruses are not passed and discharged with the wastewater. It only allows the water molecules and Oxygen molecules which are smaller than 0.0001 microns to pass, so as to achieve the purpose of purification.

The pretreatment machine makes good use of stainless steel multiple-medium filter, active carbon filter, ion exchanger to remove large particles and suspension effectively, which is aimed at improving water quality and enhancing input water index of RO membrane. At the same time it effectively discharges additional smell and residue chlorine, and improves the taste of water. The principle part is equipped with American efficient and low-voltage composite membranes; the desalination rate of each one is up to 99%. Imported from South Korean, the high and low voltage protection decreases the failure of the machine to 0. The effluent water is up to national purified water standard. All of the parts are integrated to one so that it is convenient to install and transport. Its structure is reasonable, and appearance is generous.