Biogenic Hydrogen Sulfide Production Using Elemental Sulfur and Low-Cost Organic Substrates to Remove Metal Ions from Mining Effluents

One of the best technologies available for metal removal from mining effluents is precipitation metals as sulfides. However, high cost and difficulty in managing reagents limit its widespread application. Recent literature suggests use sulfur-reducing bacteria (S°RB) a safe effective alternative to producing H2S. Nevertheless, direct substrates S°RB are high-cost low molecular compounds. This research aimed evaluate ability produce sulfides by consortia fixed-bed bioreactors using complex organic substrates. Consortia enriched cellulose or Spirulina electron donors were phylogenetically characterized fluorescent situ hybridization. Microorganisms belonging Bacteria Archaea involved, being most representative δ-Proteobacterias. The results obtained test tube culture indicated that these could alkaline conditions, resulting sulfide production. Upflowed implemented establish optimal parameters., H2S volumetric productivities ranging 1.94 2.94 mol/m3∙day. In conclusion, an active biomass with significant sulfidogenic activity can be generated under upflowed regime Spirulina.