Municipal Wastewater Treatment in a New Type Bio-carrier Reactor

A newly designed bio-carrier was used in an A/O system to investigate nutrients removal from municipal wastewater. The system was operated for 120 days including two successive phases. Only bio-carrier was used in Phase I without suspended sludge. Suspended sludge was combined with biofilm in Phase H. Results showed that in the whole process, removal efficiency of COD, NH4+-N and TN could be respectively up to 76.0%, 72.6% and 43.3%. A/O system obtained the best treatment effect under the condition of HRT=16.7h and internal flux radio=1150%. And in the same conditions, suspended sludge-biofihn in Phase II performed a better removal effect than biofilm in Phase I. In addition, a simplified mathematical model was proposed, which provided an accurate tool for describing the steady-state suspended sludge-biofilm system. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Conference ESIAT2011 Organization Committee.