Through its new forms of metal-selective ion exchange media and new approaches to ion exchange processes, Dow Water & Process Solutions (DW&PS) has helped the mining industry recover valuable metals in the most efficient manner possible over several decades. Dow ion exchange resins, ultrafiltration modules and reverse osmosis and nanofiltration membranes can provide the core products and technologies needed to help mining operators purify and recover water, as well as address ever-stricter environmental regulations and sustainability goals.
Based on more than 60 years of experience in providing hydrometallurgic solutions to the mining industry, Dow is a leading supplier of ion exchange resins and processing technologies. Dow technology is a standard-bearer for the global uranium mining industry, and we are continually developing new and better methods for primary metal separations for such elements as cobalt, nickel and gold. Additionally, Dow products and solutions offer efficient and cost-effective removal of metal contaminants from chemical process streams, plating solutions and rinse water.
Ion exchange resins and technology for uranium mining
Dow is a premier, global supplier of ion exchange resins and technology to the uranium mining industry. While traditional solvent extraction methods of uranium mining are still used, ion exchange is a preferred method of recovery from pregnant leach solutions of uranium, and Dow Amberstep resins have been specially developed to extract uranium from ore.
With its low cost and high extraction rate, acid leaching with sulfuric acid is the most common method of extracting uranium from ores. Current mining practices using lower-concentrate leaching solutions generate large volumes of pregnant leach solutions, which favour using ion exchange for recovery and purification because ion exchange can economically concentrate uranium from large volumes of pregnant leach solutions.
Improving cobalt, nickel and gold recovery processes
With cobalt, Dowex chelating resins help refiners to produce high-grade cobalt more easily than other technologies. For nickel, Dow’s chelating resin is distinctly suited for metal recovery from very acidic process streams.
Dow is also pioneering new techniques of extracting gold and nickel from previously hard-to-process ores. For example, Dow helps miners to now successfully extract gold from carbonaceous and high-copper ores, as well as nickel from lateritic ores.
Rinse water and waste effluent ion exchange treatment
Ion exchange is a well-proven technology to reduce chromium, cadmium, nickel, copper, lead and zinc metal wastes in metal plating industry applications. As mining operations become increasingly environmentally sustainable worldwide, Dow ion exchange technology is an effective option for treating process rinse waters and waste effluent.
These resins are also highly versatile for removing and recovering a wide variety of trace metal contaminants, as well as preparing mine water for recycling or discharge. Membrane technology can also be employed to recover and recycle the acid that is used in the leaching process, thereby reducing operational costs.