Use of RO and NF for treatment of copper containing wastewaters in combination with flotation

The process of so-called membrane flotation can be used in combination with NF/RO techniques for treatment of wastewaters containing copper and other heavy metals to decrease the environmental risks. Microporous inorganic membranes are used in membrane flotation process as diffusers for air sparging. Various ways of combination of flotation and membrane filtration in cationic wastewater treatment practice are discussed. With these combined membrane/flotation solutions wastewaters can be treated with high rejection and high pure water recovery. High performance of integrated membrane-electroflotation equipment as well as RO and NF spiralwound systems allows to achieve great economy of freshwater and to diminish wastewater discharge fees.