APPLICATION OF ANOXIC BATCH PROCESS TO TREAT HIGH NITROGEN CONCENTRATION OF LEAKAGE FROM OLD LANDFILLS

Abstract

This study aims to treat TNO_x (nitrogen oxides include nitrite and nitrate) in leakage of old landfills by anoxic biological methods  with TNO_x concentration is about 1,000 mg/L. Anoxic sequencing batch reactor is applied in this study. Denitrification using anoxic reactor hasn't had obvious indication of anammox mechanism, however, nitrogen removal through denitrification is high if it is supplied with sufficient carbon. The optimal ratio between added COD and N-nitrite is 1.5:1 and the ratio between reducing COD and reducing nitrite is 2.2:1 in which 30% of reducing COD is available COD in wastewater. The nitrite removal may achieve 95% if nitrogen loading is 0.115 (kg reducing N-NO₂/m³.day) or 0.115 (g reducing N-NO₂/g MLSS.day). Therefore, total N-ammonia removal of biological treatment is about 80-85%.