[Acceleration the stabilization of waste in bioreactor landfill by sequential anaerobic and semi-aerobic operation]

Based on the comparison between anaerobic, aerobic and semi-aerobic bioreactor landfill, the method to acceleration the stabilization process of waste in bioreactor landfill by sequential anaerobic and semi-aerobic operation mode was brought forward and put into practice in simulated experiment. When the operation mode was changed from anaerobic mode to semi-aerobic mode in the 710th day, the COD concentration of simulated bioreactor landfill column D1 (leachate recirculation once everyday) and D4 (leachate recirculation twice every week) was dropped from 705mg/L, 669mg/L to 135mg/L, 178 mg/L and the ammonia-N concentration was dropped from 650 mg/L, 877mg/L to undetectable level after 360 days. At the same time, the COD concentration of control column D2 and D3 was dropped from 435mg/L, 852mg/L to 295mg/L, 596mg/L and the ammonia-N concentration was dropped from 654 mg/L, 1107 mg/L to 469mg/L, 783mg/L. The rate of COD and ammonia-N concentration drop in leachate was enhanced largely after the operation mode of simulated bioreactor landfill column was changed from anaerobic mode to semi-aerobic mode. It was also shown that higher leachate recirculation frequency is more favorable for this process.