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PubMed · 17174088

Lead removal through biological sulfate reduction process.

Tran Thi Hien Hoa·Warounsak Liamleam·Ajit P Annachhatre
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Abstract

The feasibility of lead removal through biological sulfate reduction process with ethanol as electron donor was investigated. Sulfide-rich effluent from biological process was used to remove lead as lead sulfide precipitate. The experiments were divided into two stages; Stage I startup and operation of sulfidogenic process in a UASB reactor and Stage II lead sulfide precipitation. In Stage I, the COD:S ratio was gradually reduced from 15:1 to 2:1. At the COD:S ratio of 2:1, sulfidogenic condition was achieved as identified by 80-85% of electron flow by sulfate reducing bacteria (SRB). COD and sulfate removal efficiency were approximately 78% and 50%, respectively. In Stage II, the effluent from UASB reactor containing sulfide in the range of 30-50 mg/L and lead-containing solution of 45-50 mg/L were fed continuously into the precipitation chamber in which the optimum pH for lead sulfide precipitation of 7.5-8.5 was maintained. It was found that lead removal of 85-95% was attained.

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Chemical PrecipitationHydrogen-Ion ConcentrationLeadOxidation-ReductionSulfatesJournal ArticleResearch Support, Non-U.S. Gov't

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Tran Thi Hien Hoa, Warounsak Liamleam, Ajit P Annachhatre. 2006-12-14. Lead removal through biological sulfate reduction process.. https://doi.org/10.1016/j.biortech.2006.09.060

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