Rate determination of supercritical water gasification of primary sewage sludge as a replacement for anaerobic digestion

► Supercritical water gasification of primary sewage sludge was studied. ► Gasification efficiencies were measured as a function of residence time. ► Three different solids concentrations were examined. ► Arrhenius parameters were determined for this process. ► The size of reactor needed to replace digesters was determined.