Sulfide oxidation bacteria and innovative sulfide oxidation process

There are three kinds of sulfur bacteria (filaceous sulfur bacteria, synthetic sulfur bacteria and colorless sulfur bacteria), and they could consume sulfide and excrete sulfur intracellularly or extracellularly. The characteristics of these sulfur bacteria, the operational conditions for sulfur producing, and the latest research status of biological sulfide removing processes home and broad were summarized in this paper. It was shown that colorless sulfur bacteria had high sulfur producing rate and twenty grams sulfur could be produced extracellularly while one gram cell weight is increased. Therefore, this kind of bacterium is suitable to be applied in the future industrialized sulfide removing process. The development trend of sulfide removing processes both in research and application, and the key standards of those processes were also summarized. In the author's viewpoint, sulfide removing process could be widely developed in the near future for its low energy consuming, low investment and suitable operational conditions. In addition, the molecular mechanism of biological sulfide removing from the points of enzymology and genetics has been discussed as well. It was indicated that the novel engineering bacteria reconstructed by gene engineering technology would have higher efficiency of sulfide removing.