Masaaki HOSOMI, Kazuo MATSUSHIGE, Yuhei INAMORI and Ryuuichi SUDO

(National Institute for Environmental Studies, Water and Soil Environment Division)

Abstract

Laboratory scale experiments on aerobic/anaerobic operations of the sequencing batch reactor (SBR) activated sludge processes were conducted. The aim of these experiments was removal of nitrogen and refractory organic compounds in municipal landfill leachate by adding methanol as a hydrogen donor. NH4-N concentrations in leachate ranged from 100mg/L to 200mg/L. A high concentration of refractory organic compounds (10mg/L to 150mg/L as COD) was observed in the leachate. 95% or more nitrogen removal was achieved in the operation with an optimum length of aerobic and anoxic/anaerobic period for nitricication-denitriofication process. About 50% removal for refractory organic compounds was achieved by the SBR activated sludge process with the combination of ozonation as pretreatment.

Key words: municipal landfill site, leachate, sequencing batch reactor activated sludge processes, nitrogen, refractory organic compounds