Concentrated brine of coal chemical industry (namely the concentrated solution of phenol wastewater treated by hollow fiber, RO and concentrated liquid treated with concentrated water RO) contains small molecules of COD that are difficult to degrade (mainly caused by inorganic phenolic sodium). The conventional process uses "nanofiltration NF separating salt and evaporative crystallization". However, the concentration of NF contains large amount of organic matter, which causes large amount of mother liquor in subsequent evaporation and makes crystallization difficult. Moreover, the crystallized solid can only be treated as solid waste.
MEY membrane technology process:
Advantages:
● Organic separation membrane can reduce the cleaning frequency of NF membrane and prolong the service life of NF membrane.
● After organic separation membrane treatment, the COD content of NF concentration solution is low. After evaporation treatment, the amount of mother liquor is small, and it can be made into industrial grade sodium sulfate.