Limestone and Lime Neutralization of Ferrous Iron Acid Mine Drainage.

摘要

The U.S. Environmental Protection Agency conducted a 2-yr study on hydrated lime and rock-dust limestone neutralization of acid mine drainage containing ferrous iron at the EPA Crown Mine Drainage Control Field Site near Rivesville,West Virginia. The study investigated optimization of the limestone process and its feasibility in comparison with hydrated lime treatment. Operating parameters,design factors,and reagent costs for both processes were determined. Effluent quality was considered of prime importance in these investigations. Coagulants were considered essential to successful thickener operation for both lime and limestone treatment. Effluent iron,suspended solids,and turbidity values could be maintained below 3mg/l, 10mg/l,and 10 JTU,respectively,using coagulant addition. Although the limestone process was demonstrated to be technically effective in ferrous iron treatment situations,the process was judged to be less efficient overall in comparison with lime neutralization.