Experimental Study on Thermal Hydrolysis and Anaerobic Digestion of Sewage Sludge

Sewage sludge was pretreated by using thermal hydrolysis process before anaerobic digestion.The result showed that the optimal temperature for thermal hydrolysis is 170 ℃ and reaction time is 30 min.Both the anaerobic digestion performance of thermally hydrolyzed sludge and treatment efficiency of the system are improved significantly with COD removal increased by 20.18% at maximum and average daily gas production increased by 79.20%～99.55%.