The Center for Advanced Mineral and Metallurgical Processing (CAMP) at Montana Tech of the University of Montana has been using nitrogen-species-catalyzed (NSC) pressure leaching followed by an alkaline sulphide (AS) gold recovery to salvage gold bullion from mounds of old gold tailings 40 km south of Butte.
In the past, the NSC/AS technology was used on an industrial scale to recover copper, silver and antimony.
CAMP has been applying this technology through funding from the Center for Advanced Separation Technologies (CAST), a consortium of major universities that conducts research into advanced separation technology. The centre tries to solve various problems facing the U.S. mining industry.
But it is Canadian-based junior Profile Resources that has been reaping the most rewards from non-cyanide recovery. Besides restarting the past-producing Waseka mill and producing gold at the rate of 10 oz. per day, Profile is working with CAST to develop a pilot-scale plant employing the NSC/AS gold recovery technology.
In June 2003, Montana’s Department of Environmental Quality issued an opinion that the company’s Waseka mill, about 50 km south of Butte, is entitled to a “small miner’s” exclusion under the state’s environmental protection legislation, which has maintained a blanket ban on gold milling using cyanidation since 1998, when a citizen ballot initiative prohibited cyanide milling circuits in both new and expanded gold operations.
There are 30 mines in Montana that can not process ore because there are no processing facilities in the area. Profile Resources will process ore from surrounding mines and, in particular, 100-year-old gold-bearing waste dumps. This should provide an economic benefit while enhancing Montana’s environment.
CAST was originally established as a partnership between VirginiaTech and West Virginia University, but the partnership has expanded to include Montana Tech, the University of Utah, the University of Nevada, New Mexico Tech, and the University of Kentucky.
— The preceding is from an information bulletin published by the Center for Advanced Separation Technologies in Blacksburg, Va.
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