AWWA ACE61758

The use of reverse osmosis (RO), nanofiltration (NF), and electrodialysis (ED) for water treatment is expanding as water suppliers recognize the capabilities of these membranes to covert saline or poor-quality supplies into potable water. With the increasing installation of desalination plants, however, management of residuals from these processes is a growing issue. It is also a challenging issue because of the high level of total dissolved solids and the large volume of residual (relative to conventional treatment processes). Many regulatory agencies, utilities, and design engineers are unfamiliar with the characteristics, treatment, and disposal of desalting membrane residuals. This article provides background on the issues surrounding desalting membrane residuals and presents basic information about the desalting process and addresses residual management. Water utility managers who are considering using RO, NF, and ED for water treatment can use this report to determine methods to cost-effectively handle, treat, and dispose of the residuals from these membranes. Includes 9 references, tables, figures.