Sustainable Treatment and Resource Recovery from Sewage Sludge

Sewage sludge generated during wastewater treatment in wastewater treatment plants (WWTPs) leads to environmental pollution because of the presence of pollutants such as polycyclic aromatic hydrocarbons, furans, heavy metals and pathogens. Sustainable treatment of sludge and using it for energy and resource recovery is an attractive solution for managing the high sludge generation. This chapter comprehensively illustrates the various conventional and emerging technologies such as anaerobic digestion, incineration, pyrolysis, gasification, hydrothermal treatment, wet air oxidation, supercritical water oxidation and bio-electrochemical systems for sludge treatment with a comparative assessment of their operating parameters, technical challenges and advantages. Further, the recovery of resources such as enzymes, bioplastics, biopesticides, biofertilizers, proteins and nutrients from sludge is discussed in detail. The use of sludge as a valuable resource will develop sustainable energy solutions for the current and future generations and reduce our dependency on non-renewable resources. The present chapter will improve our understanding of recovering resources and energy from sewage sludge by advanced technologies.