LOW TEMPERATURE THERMAL PRETREATMENTS FOR THE IMPROVEMENT OF WASTE ACTIVATED SLUDGE ANAEROBIC DIGESTION

摘要

Activated sludge is the main waste from municipal wastewater treatment plants (WWTPs) with a specific production of about 22-30 gVS/inhabitant day (VS, volatile solids). Anaerobic digestion (AD) is of particular interest in the treatment of activated sludge because of its capacity to reduce the total amount of biosolids while producing high methane content (50-60% v/v) biogas. However, when referring to activated sludge, it is well known that the complexity of its structure limits the biological process. So, in order to improve the efficiency of the AD process, low temperature thermal pre-treatments have been tested and the results are presented in this paper.