Electrodialysis membrane technology for industrial wastewater treatment: recent advances

The increasing quantities of industrial wastewater generated annually cause severe problems of waste disposal due to the high concentration and complexity of the waste streams. Electrodialysis (ED) has been widely applied for industrial wastewater management. It is highly efficient in fractionating and recovering resources from toxic streams, while producing water and/or other valuable components with high purity and high energy efficiency. This chapter highlights the recent advancement of the ED technology for industrial wastewater treatment. After a brief account of the historical development of ED, the basic theory of ED and ion exchange membranes (IEMs) are introduced. Since the separation performance of ED is mainly determined by the properties of the IEMs, the various membrane types are introduced, including the heterogeneous IEMs, the homogeneous IEMs, the monovalent IEMs, the bipolar membranes, and the polymer inclusion membranes. The design of an ED system varies with the waste effluent composition of a specific industry. Accordingly, ED processes are categorized based on its application aims, that is, water reclamation, nutrient recovery, metals recovery, chemicals generation, and other emerging applications, and the typical process configurations are discussed. Finally, future efforts at IEMs innovation and ED system design are highlighted for further thoughts to be curated on enhanced process efficiency. This chapter offers a comprehensive understanding on the recent advancements of ED technology for industrial wastewater management.