International Mining’s July issue with a major focus on water management is currently at the printer. In it there is discussion of the growing interest in desalination to produce water for mines in arid areas. Along these lines,  Veolia Water Solutions & Technologies has acquired worldwide rights to commercialise a new patented Zero Discharge Desalination (ZDD) technology developed at the University of South Carolina by ZDD, Inc. The technology uses a combination of separation processes, including an electro-dialysis device in an ion substitution mode to remove divalent salts from water. This process prevents the salts from precipitating during the process of producing purified water and allows greater water recovery than would otherwise be achieved. Recent pilot testing has proven that the technology can achieve 97% recovery on brackish water over an extended time period. Large-scale piloting will be completed in 2009 to validate life cycle costs prior to a demonstration plant being built. As part of the larger-scale piloting, a separate cost analysis will determine the marketability of beneficial byproducts produced by the process.

Applications of the technology include greenfield desalination sites and retrofit of existing Reverse Osmosis (RO) facilities, where ZDD is expected to increase recovery rates from 75 to 97%; various industrial applications to enhance water reuse capabilities; and seawater desalination to improve water recovery rates and produce multiple byproducts.