The effect of aeration position on the spatial distribution and reduction of pollutants in the landfill stabilization process-a pilot scale study

Three pilot-scale simulators with different aeration systems were constructed to explore the effects of aeration position on the reduction of pollutants. The simulator with a bottom aeration system successfully distributed oxygen and efficiently inhibited methane production. A close relationship was found between the oxygen distribution and the removal of pollutants, especially that of nitrogen. The transition between nitrification and denitrification in the longitude direction of the simulator with a bottom aeration system contributed to nitrogen removal in aerobic conditions. This process can be defined as a new path for nitrogen removal in addition to simultaneous nitrification and denitrification. The concentration of NH4+-N, total nitrogen and total organic carbon dropped to 3, 78 and 204 mg L-1, respectively, after 312 days of bottom aeration and to 514, 659 and 828 mg L-1, respectively, after 312 days of top aeration. These results indicate that the bottom aeration system was more efficient for reducing pollutants than the top aeration system.