Sulfate-reducing bacteria(SRB) in sewage sludge and release of H2S
污泥硫酸盐还原菌(SRB)与硫化氢释放

Simulations were conducted on the release of hydrogen sulfide (H2S) from different types of sludge during the low-temperature sludge drying process. The biomass and activity of sulfate-reducing bacteria (SRB) in various sludges and the corresponding H2S release were studied by cultivating the bacteria. The results show that larger biomass and stronger SRB activity in sludge correspond to more H2S release. Neutral to acidic sludges release more H2S than alkaline sludges. The alkaline sludge not only neutralizes H2S but also suppresses SRB growth, thus reducing the amount of H2S produced by the microbes. During sludge drying, the amount of H2S released increases with drying temperature. The maximal amount of H2S release occurs in the early stage of sludge drying. The above findings provide a scientific basis for effective control of H2S release in the sludge drying process.