Characteristics and mechanism of dimethyl trisulfide formation during sulfide control in sewer by adding various oxidants

Sci Total Environ. 2019 Jul 10:673:719-725. doi: 10.1016/j.scitotenv.2019.04.131. Epub 2019 Apr 10.

Abstract

The addition of chemical agents to control the production of hydrogen sulfide (H2S) is currently the principal technology used to control odor emissions from sewers. In this study, laboratory reactors were used to investigate the change in dimethyl trisulfide (DMTS) concentrations when dosing with oxidant to control sulfide in sewers. Our results show that the intermittent addition of oxidant leads to sulfide regeneration and increased DMTS formation. Additional experiments were conducted to investigate the processes that result in the formation of DMTS. The results indicate that the polysulfide produced after oxidant addition was a key intermediate in DMTS production. Enzymatic methylation of polysulfide was an important process in DMTS formation. Dimethylsulfoxide (DMSO) was observed in the reactor when oxidant was again added but it was reduced to DMTS when the oxidant was depleted. There are side-effects of adding oxidant, and alternative control measures for volatile sulfur compounds (VSCs) need to be investigated further.

Keywords: Odorants; Polysulfide; Sulfide control; Volatile sulfur compounds (VSCs).