AWWA MTC64609

The Indian Wells Valley Water District (IWVWD) is located in Ridgecrest, California, in northeast KernCounty, about 120 miles from Los Angeles. It represents a true in-land location for a possibledesalination facility, with no access to the ocean for concentrate disposal. Part of IWVWD's mission isto explore alternative drinking water sources, including treatment of poorer quality water from withinthe Indian Wells Valley, such as the brackish water (TDS around 2,000 mg/L) from their NorthwestWell Field (NWWF). This work forms part of a desalination investigation and preliminary designundertaken for IWVWD.Treating brackish water implies a desalting process, and therefore production of a concentrate stream. Inthis case, due to the in-land location, there are some significant challenges associated with the brinedisposal. Twelve different desalting trains and associated brine treatment and disposal processes wereevaluated to result in a zero-liquid-discharge (ZLD) configuration.This project evaluated water quality from four existing wells in the NWWF, which was used as a basisfor process evaluations. The groundwater is complex in nature, with moderate salinity and high levels ofsparingly soluble salts (such as calcium carbonate and calcium sulfate) and silica. It also contains anumber of contaminants that exceed certain drinking water Maximum Contaminant Levels (MCLs).The study was undertaken to determine potential desalting treatment trains that would be able to treat aworst-case blend of well water to drinking water standards. An evaluation was performed, based onpredetermined criteria, to screen and select the most promising treatment train for the IWVWD toimplement. This treatment train would recover over 98 percent of the NWWF water as drinking water,and discharge the remainder to a small evaporation pond.Mass balance models were developed in order to establish preliminary sizes of each of the unitprocesses. From the unit sizes, both capital and operating cost estimates were made. Includes reference, tables.

Product Details

Edition:

Vol. - No.

Published:

03/01/2007

Number of Pages:

9

File Size:

1 file , 350 KB