Treatment of acidic water containing iron and sulfate comprises microbial oxidation of iron compounds and the formation and precipitation of iron hydroxysulfate

摘要

Treatment of acidic water containing iron and sulfate comprises microbial oxidation of iron compounds at a pH below 2.8 in a first treatment zone and the formation and precipitation of iron hydroxysulfate at pH 3.2-3.5 in a second treatment zone. The oxidation rate is controlled by recycling microorganism-containing iron hydroxysulfate and/or supplying air containing carbon dioxide so that the water residence time is very short.