Sulfur Reduction at Hyperthermoacidophilic Conditions with Mesophilic Anaerobic Sludge as the Inoculum.

摘要: Sulfur reduction at hyperthermoacidophilic conditions represents a promising opportunity for metal sulfide precipitation from hot acidic metallurgical streams, avoiding costly cooling down. The suitability of mesophilic anaerobic sludges as the inoculum sulfur-reducing bioreactors operated high temperature and low pH was explored. We examined full-scale reactors activity 2.0-3.5 70 or 80 °C, with H2 an electron donor. At 3.5 in batch experiments, sulfidogenesis started within 4 days, reaching up to 100-200 mg·L-1 dissolved produced after 19-24 depending on origin sludge. Sulfidogenesis resumed removing H2S by flushing nitrogen gas, indicating that limiting conversion. best performing sludge used inoculate L gas-lift reactor fed donor, CO2 carbon source, elemental sulfur acceptor. semibatch mode stable production rates 60-80 mg·L-1·d-1 were achieved period 24 without formation methane acetate. Our results reveal potential seed material bioprocesses conditions. process needs further optimization volumetric rate gain relevance practice.