Abstract
In order to investigate the operating differences by different temperatures as first stage in a temperature phased anaerobic digestion (TPAD), continuous experiments were conducted combining a thermophilic(55°C) first stage and a mesophilic(35°C) second stage, named TM-TPAD, and then combining a hyper-thermophilic(70°C) first stage and a mesophilic(35°C) second stage, named HM-TPAD, focusing on the long-term performance, organic degradation and particle hydrolyzation. The experiments of a single mesophilic(35°C) anaerobic digestion (MAD) were also carried out as comparisons. In this study, the HM-TPAD was operated stably in the long run, achieving a volatile solids (VS) destruction of 51.8%, which was 1.39-folds and 1.16-folds of the values of TM-TPAD and MAD respectively. It can also be concluded that the higher temperature is set to the first stage, the more efficient organic degradation and particle hydrolyzation is obtained for WAS digestion.
