A wide variety of types of sludge, including municipal sewage sludge, are treated in anaerobic digesters.
In these digesters, there is a certain amount of biogas created and this consists of CH₄, CO₂ and H₂S. This biogas is often used for creating green energy.

These sludge digesters produce biogas, which can contain H₂S. For reasons related to health, safety and corrosion, removal of H₂S is required. Hydrothane STP can offer both the HydroThane Chemical Scrubbing Process and the HydroThane Biological Scrubbing Process.

HydroThane BSP technology is the best method for H₂S removal combining deep H₂S removal, a very high reliability and availability, and low lifecycle costs. The clean biogas can be used to produce electricity or to replace natural gas in a boiler.