AWWA MTC69751

East Bay Municipal Utilities District (EBMUD), Contra Costa Water District (CCWD), SanFrancisco Public Utilities Commission (SFPUC), and Santa Clara Valley Water District (SCVWD)are joining forces to investigate desalination as a potential regional solution to water supplyreliability. To enhance their dry year supplies, the Partner Agencies are conducting studies thatcould result in one or more regional desalination facilities with an ultimate total capacity of up to71-mgd in Northern California.One of the challenges for this project is unique water quality. The site selected for pilot testing isthe estuarine junction of the San Francisco Bay and its freshwater tributaries, where raw watersalinity can fluctuate by an order of magnitude on a tidal and seasonal basis. Traditionalmembrane technologies for desalination have been developed to treat either brackish water orseawater. These coarse classifications can be applied when raw water quality can becategorized as one or the other, but are less readily applicable in surface waters with significanttidal influence.In order to address fluctuating water quality with the available suite of membrane technologies,several innovative design approaches have been selected for pilot testing. Three desalinationtrains are being operated in parallel, integrating a variety of membrane type configurationsincluding nanofiltration (NF), brackish water, and seawater elements in one-stage and two-stage configurations.The objective of pilot testing is to determine the efficacy of each configuration with respect to feedwater quality, process efficiency, and long-term operation.Pilot testing is underway and will continue through early 2009. The side-by-side comparison ofthree different treatment approaches during this pilot study will generate valuable information forthe water industry. Detailed findings are presented to highlight treatment efficiencies andoperational experiences in evaluating the performance of various membrane configurations intidally fluctuating feed water quality. Includes tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2009

Number of Pages:

15

File Size:

1 file , 1.1 MB