jailcd2020082: Environmental Assessment of Sewage Sludge-to-Energy Systems in China

Abstract

In sludge management, sludge is increasingly perceived as a marketable product rather than as waste material. With ongoing economic development and population growth in China, large quantities of wastewater are discharged and substantial amounts of sewage sludge are generated, which is a potential biomass energy resource. Utilization of waste sludge as a renewable resource for energy recovery is the appropriate solution of how to manage the continuously increasing waste sludge generation effectively. This study used data from statistics yearbooks and pieces of literature to distribute the spatial-temporal sludge generation and evaluate the potential of bioenergy production. IPCC method employed to identify the environmental influence of potential bioenergy production under the three common sludge-to-energy method: sludge incineration to electricity, sludge anaerobic digestion for biogas to electricity and through combined heat and power unit and sludge digestion and incineration. The use of wastewater sludge as a source for energy and resource recovery is a good alternative for its management considering the legislation requirements and the circular economy principles. Our findings provide a sludge disposal reference for the government and industries. For further study, it is suggested to add the sewage sludge-to-energy system into sewage sludge management and energy policy, which would perform a higher bioenergy resource and GHG emissions reduction potential.