Papers by Author: S. Kutschke

Abstract: Piles and dumps in mining sites of lignite and ore mines very often generate drainage water with a low pH value. Furthermore they are contaminated with heavy metals or radionuclides. A comprehensive sustainable remediation and / or a water treatment process requires an assessment of the water quality and the determination of the future development thereof. This, in turn, requires prediction of the microbial processes which are responsible for the release of heavy metals and radionuclides. The paper deals with the demonstration of a suitable method for the prediction of these reactions and water quality.

Abstract: Water draining a waste dump at the Hartenstein site of the former uranium mining company SDAG Wismut is characterised by an uranium concentration between 1mg/L and 3 mg/L and a nitrate concentration from 30 mg/L to 120 mg/L. A microbiological process was developed between 2001 - 2003 under laboratory conditions and, after this time, the process was scaled up to a technical plant. The water was treated continuously by a controlled microbiological process under anaerobic conditions with methanol as the sole carbon and energy source. The reduction plant is a basin filled with about 540 m³ of gravel and with a free water volume of about 200 m³. The plant was foreseen for the treatment of a drainage water flow rate of 2 m³/h – 5 m³/h. The residence time of the treated water in the plant comprises 40 h– 100 h according to the water flow. The continuous process started in 2004. The Uranium concentration decreased to values lower than 0.5 mg/L. The arsenic concentration varied in a range from 60 to 80 .g/L after reaching stable anaerobic conditions. The plant worked also during deep temperatures in the wintertime.