Reverse osmosis membrane technology is one of the fastest developing, widely used, and successful membrane separation technologies. Especially in the field of water treatment, it creates high annual output value. Among all kinds of membrane products, the reverse osmosis membrane occupies half of the sales, which is one of the main membrane products with a promising development prospect.
The raw water quality and the treated water quality of wastewater require three-level or multi-level treatment processes, known as deep wastewater treatment. It is commonly used to remove trace COD and BOD organic pollutants, SS and high-concentration nutrients such as nitrogen, phosphorus, and salt in the water. RO membrane technology should be one of the important process means for deep wastewater treatment. Membrane technology can remove salts, colloids, microorganisms, bacteria and such in water. Currently, ro membrane technology can roughly be divided into microfiltration membranes, ultrafiltration membranes, nanofiltration membranes and reverse osmosis membranes, which differ according to their filtration accuracy. It can be seen that the pore size of the reverse osmosis membrane is smaller, and under the same sewage treatment demand, its treatment capacity is stronger. In addition, ro membrane technology has many advantages, such as good water quality, low energy consumption, and no pollution. When applied to the deep treatment of wastewater, reverse osmosis membrane can block all dissolved inorganic molecules and any organic substances with a relative molecular mass greater than 100. It can not only effectively purify industrial wastewater, but also recycle useful materials and save energy.
High-salinity wastewater refers to wastewater with a mass fraction of organics and total dissolved solids TDS≥3.5%, including high-salt domestic wastewater and high-salt industrial wastewater. If it is directly discharged without treatment, it will inevitably cause huge harm to water body organisms, domestic drinking water and industrial and agricultural production water. The traditional method for treating high-salinity wastewater generally uses evaporation and crystallization technology. After high-salinity wastewater is heated and evaporated, the temperature is lowered for cooling to produce crystallized salt substances. This part of the salt can be reused, but the remaining large amount of concentrated brine water due to its high salt concentration does not meet the discharge standard and must be further concentrated. However, the energy consumption required for evaporation and crystallization is high, and the daily operation cost is also high, so it is generally not recommended to use.
RO membrane technology is currently a common desalination technology, which has high durability, high water output, and high separation efficiency compared with traditional technology. It can effectively purify water containing biological contamination and organic matter. The good desalination effect of the reverse osmosis membrane element can make the water production effect more excellent, and the wider channel has higher tolerance for pollutants.