title: Long term performance of an AMD treatment bioreactor using chemolithoautotrophic sulfate reduction and ferrous iron precipitation under in situ groundwater conditions.
abstract: Chemolithoautotrophic sulfate reduction (CSR) was tested to treat natural acid mine drainage influenced groundwaters. The long term behavior was studied for more than 3 years under groundwater conditions (10 °C, autochthonous sulfate reducing bacteria (SRB)) without biomass replenishment in a 190 L bench scale reactor. The process produces water with alkalinity >10 mM. pH can be controlled by p(CO(2)) for all expectable water qualities. SRB were immobilized using an expanded clay bed. After 1.3 years of operation, a constant biomass content and sulfate reduction rate of 0.25-0.30 mmol(so)₄(Lh)⁻¹ were established. The sulfate reduction rate was limited by biomass content. Most of the electrons were used for sulfate reduction (98%). The hydrogen turn over in competing processes like methanogenesis and homoacetogenesis was successfully suppressed by adjusting the sulfate concentration to be >2 mM in the runoff.
authors: Dresden Groundwater Research Centre (DGFZ), Meraner Str. 12, 01217 Dresden, Germany. fbilek@dgfz.de
authors: F
authors: F
authors: Bilek
authors: S
authors: S
authors: Wagner
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D019605:Euryarchaeota / Q000378:metabolism*; D060587:Groundwater / Q000737:chemistry / Q000382:microbiology*; D007501:Iron / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D008906:Mining; D010084:Oxidation-Reduction; D013431:Sulfates / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000295:instrumentation*
chemical_list: D013431:Sulfates; D014874:Water Pollutants, Chemical; D007501:Iron