Carbon Footprint Analysis of Sewage Sludge Thermochemical Conversion Technologies

Thermochemical conversion technology for sewage sludge (SS) management has obvious advantages compared to traditional technologies, such as considerable volume reduction, effective pathogen elimination, and potential fuel production. However, few researchers conducted comparative research on the greenhouse gas (GHG) emission performances of these technologies. This paper evaluates lifecycle carbon footprints three SS thermochemical including hydrothermal liquefaction (HTL) (Case 1), pyrolysis 2), incineration 3) with software OpenLCA Ecoinvent database. The results show that Case 1 smallest footprint (172.50 kg CO2eq/t SS), which indicates HTL process best GHG reduction other disposal routes. biggest contributor technologies is indirect emissions related energy consumption. So consumption ratio (ECR) cases calculated assess performances. From perspective conversion, shows performance an ECR 0.34. In addition, element balance analysis carried out deeply evaluate cases. study fills knowledge gap regarding provides a reference future selection policymaking against climate change in sector.