The effects of thermally treated biosolid residue on anaerobic digestion of waste activated sludge

Pyrolysis of biosolids is becoming more prevalent in Australia and is emerging as an opportunity to enhance solids handling associated with wastewater treatment, as the process can destroy several contaminants of concern. Based on the pyrolysis conditions several by-products can be generated, including char, syngas, aqueous and lipid fractions. There are several opportunities to reuses these fractions within existing wastewater solids handling facilities, one of which is Anaerobic digestion. The addition of thermally treated biosolid residues (biochar, aqueous and oil fractions) to the anaerobic digestion process has been proposed as a promising solution to gain value from these by-products. The addition of biochar to anaerobic digestion has the potential to improve the physical and chemical properties of sludge and enhance the performance of the process.

This PhD research aims to investigate the effects of biosolids pyrolysis by-product addition on anaerobic digestion of waste activated sludge, and to identify optimal process conditions. The findings of this research will provide insights into the potential of biosolids pyrolysis by-products for enhancing anaerobic digestion of waste activated sludge and inform the development of more efficient and sustainable wastewater treatment processes.