Autotrophic denitrification via nitrate as an effective approach for removal of dissolved sulfide in anaerobic reactors.

This work assessed the effect of adding different concentrations of nitrate (50-300 mg NO ·L) on the removal of dissolved and gaseous sulfide in an anaerobic reactor treating synthetic effluent containing sulfate (100 mg SO ·L) and organic matter (1 g COD·L). Autotrophic denitrification, stimulated by the addition of nitrate, was demonstrated to be a very effective approach for removal of dissolved sulfide even in the presence of a high concentration of organic matter (complete removal with 50 mg NO mg·L). However, it had a minor effect on HS.