Chemical and biological cyanide destruction and selenium removal from precious metals tailings pond water.
Lien-RH; Dinsdale-BE; Gardner-KR; Altringer-PB
Paper in Proceedings of EDP Congress '90 Ed by D r Gaskell TMS 1990 Oct; :323-339
The Bureau of Mines is investigating chemical and biological decontamination of complex wastewaters such as tailings pond water containing 280 ppm cn and 5 ppm se as well as significant concentrationsof arsenic, copper, iron, silver, and zinc. The most effective chemical procedure involves cyanide oxidation using hydrogen peroxide or sodium hypochlorite followed by selenium reduction using ferrous hydroxide. The effluent contains <-1 ppm cn and 20 ppb se; concentrations of other major contaminants meet EPA drinking water standards. Preliminary research indicates that biological cyanide oxidation is possible even in highly alkaline solutions (ph 10.5) Containing high cyanide concentrations; indigenous bacteria destroyed 85 pct of the cyanide. Exploratory research shows that other bacteria removed up to 79 pct of the selenium from chemically oxidized, low-cyanide water. These promising results may lead to a final processing scheme that involves a combination of chemical and biological techniques.
OP; Book or book chapter
Paper in Proceedings of EDP Congress '90