Mixing Effect on Bio-Methanation, Settleability and Dewaterability in the Anaerobic Digestion of Sewage Sludge Fractions

Biomethanation and dewaterability characteristics of primary sludge (PS), secondary (SS) mixed (MS) fractions were assessed after anaerobic stabilization under parallel batch continuous mixing conditions at 35℃ in order to investigate the performance separate digestion system. Similar methane conversion/yield values obtained PS, SS MS with mixing’s positive effect only PS digestion. Continuous resulted 50% increase yield (600(+/-100) mL/g VSadd.d. produced a comparable 650(+/-100) VSadd.d showing no due pattern. Settling stabilized superior samples. A reverse relationship was between settling where intermittent enhanced ability while higher sludges. Polyelectrolyte (PE) addition showed negative on settleability Low degree volume reduction an SVI 64 VS compared 25% 82 mode for PS. similar trend but weaker 182 15% 200 indicated much lower