Kinetic parameters of a mixed culture oxidizing sulfide and sulfur with oxygen

Abstract

Kinetic parameters of biological sulfide oxidation are described. The influence of the sulfide loading rate on growth yield and specific oxidation rate were investigated with free-cell suspensions. It is concluded that at least two types of bacteria were present, namely, sulfate producers (type A) that grow at higher loading rates. Type A bacteria have a growth yield of 04 g dry S/mol S, while type B bacteria have a growth yield of 04 g dry S/mol S. Type A has a high affinity for sulfide and is inhibited by sulfide at sulfide concentrations exceeding 10 mg/L. Type B has a low affinity for sulfide and is not inhibited by sulfide, but by oxygen.