[Effects of leachate recirculation volume on its characteristic and landfill stabilization rate]

Impacts of recirculation volume on leachate characteristic and landfill stabilization rate were studied. Four simulated bioreactor landfill columns were operated weekly with different recirculation ratios, respectively 5.3%, 2.7%, 0.67% leachate and 0.33% water, in this comparative research. The results indicate that simulated reactor with 5.3% recirculation ratio has the most rapidly stabilization rate and release the most organic pollutant. The shortest methane generation delay was also observed in this column. While simulated reactor with 2.7% recirculation ratio formed the best microbe environment and kept the highest reactor temperature 35 degrees C. It also had the best impactive load capacity and treating efficiency to leachate, and removal of COD was 77% and BOD5 was 88% respectively. In actual projects, appropriate leachate recirculation volume should be chosen according to design purpose of landfill sites.