E2.05 Ma 2017 ReNUWIt Annual Meeting Poster

The difficulty to meet the increasing demand for freshwater has driven municipalities and water utilities to explore the desalination of seawater, brackish waters, and reclaimed water as alternative water supplies. Concentrate disposal and management is a considerable challenge for the implementation of desalination technologies, especially for inland applications where concentrate disposal options are limited. Compared to reverse osmosis (RO), electrodialysis (ED) or electrodialysis reversal (EDR) are less prone to fouling and scaling, therefore require less stringent pre-treatment and are more tolerant to concentrate with high total dissolved solids (TDS) and total organic carbon (TOC). However, there is lack of understanding of ED performance and pretreatment requirements to enhance water recovery of reclaimed water and concentrate. It is imperative to demonstrate and optimize ED and EDR systems to be a viable and cost-effective concentrate treatment technology as well as to tailor product water quality for different beneficial uses.

In this project, bench- and pilot-sale experiments were conducted to investigate the desalination efficiency using normal grade ion exchange (IX) membranes and innovative monovalent permselective IX membrane to treat reclaimed water, brackish groundwater, RO concentrate (wastewater and brackish water). Water quality improvement, energy consumption and water recovery were studied.