Removal of Metal Ions from Mine Effluents Using Bacterial Reactions by Sulfate Reducing Bacteria

Metals in mine effluents, especially metal mines, have been a major environmental concern. High mobility of the metals in solution and the subsequent lowering of discharge limits by the EPA have necessitated expensive chemical treatment of the effluent. Bacteriological reactions, particularly by Sulfate Reducing Bacteria, have been known to reduce metals content in water by precipitating them as metal sulfides. The technique was used on samples of untreated mine plant water (prior to treatment for disposal) from the TeckCominco Red Dog Mine in northern Alaska. Further experiments were conducted to determine bioreactor design parameters. Bioreactor lab tests revealed that metal content was reduced by over a hundred fold. Pilot scale test cells were established in the Red Dog mining area and their performance was monitored. ______________________ 1 Poster paper presented at the 7 International Conference on Acid Rock Drainage (ICARD), March 26-30, 2006, St. Louis MO. R.I. Barnhisel (ed.) Published by the American Society of Mining and Reclamation (ASMR), 3134 Montavesta Road, Lexington, KY 40502 2 A. Choudhury, Graduate Student, Dept. of Mining & Geological Eng., University of Alaska Fairbanks, Fairbanks Alaska 99775, Dr. S. Bandopadhyay – Professor, Dept. of Mining & Geological Eng., University of Alaska Fairbanks. Dr. S. Schiewer – Asst. Professor, Dept. of Civil and Environmental Eng., University of Alaska Fairbanks.,Dr. T.E. Wilson – Adjunct Asst. Professor, Dept. of Mining and Geological Eng., University of Arizona, Tucson, Arizona 85721.