Ultrafiltration(UF) is a pressure-driven membrane separation technology. The pore size of the ultrafiltration membrane is nano-scale. Under a certain pressure, small molecular solutes and solvents pass through the ultrafiltration membrane, while macromolecular solutes cannot pass through and are rejected on the other side of the membrane.
This process is mainly used to remove macromolecular substances such as particle, colloid, bacteria and virus in water, but it can hardly remove inorganic salt ions.
Activated carbon is hydrophobic adsorbent made of carbon-based substances through high-temperature carbonization and activation. Activated carbon has a black appearance, developed pore structure, huge specific surface area and strong adsorption performance, which can effectively remove residual chlorine and smelling in water.
Reverse osmosis is a separation method that separates solutes from solvents by selective interception of semi-permeable membrane under pressure. The semi-permeable membrane with this function is called RO membrane.
Under pressure, water molecules can pass through the RO membrane, while inorganic salts, heavy metal ions, organic matter, colloids, bacteria, viruses and other impurities cannot pass through the RO membrane, so that pure water and concentrated water can be strictly separated.
Electro deionization (EDI) technology relies on the ion exchange effect of ion exchange resin and the selective permeation of anions and cations by anion and cation exchange membrane. Ions migrate in a direction under the action of the DC electric field to achieve the deep removal of ions.
At the same time, water molecules generate hydrogen ions and hydroxide ions under the action of the electric field. These ions regenerate the ion exchange resin, so that the ion exchange resin keeps running continuously and produces Type II water with stable quality.
Distillation separates water from contaminants by changing it from liquid state to gaseous state and back to liquid state. In theory, distillation can remove most types of contaminants from water, except for substances with vapor pressures and boiling point close to water. However, the speed of producing pure water by distillation is slow, and the energy consumption is very high.