Advancements in sludge pyrolysis: Integrated resource recovery and process-derived pollutant mitigation

Abstract

Pyrolysis is an environmentally friendly technology with significant potential for sludge resource recovery and treatment. This review examines key factors influencing sludge pyrolysis, such as temperature, heating rate, and residence time, and their impacts on the yield and quality of pyrolysis products. The potential applications of these products are extensive, and their sustainability can be evaluated through energy balance analysis. Moreover, co-pyrolysis and catalytic pyrolysis are crucial in improving product quality and controlling pollutant emissions. Therefore, this review focuses on various co-pyrolysis materials and catalysts, highlighting their roles in enhancing product quality and elucidating the mechanisms underlying these improvements. Strategies for managing the release of nitrogen, sulfur, and heavy metal pollutants are also discussed. Finally, the review presents recent advancements in sludge pyrolysis and provides recommendations for future research to further enhance the technology and expand the applications of pyrolysis products.