Pilot-scale landfill with leachate recirculation for enhanced stabilization

A pilot-scale landfill and a two-phase (acidogenesis and methanogenesis) anaerobic sequencing batch reactor (anSBR) system was setup to treat leachate collected from the simulated landfill cell which had leachate recirculation (at <0.3% of total waste volume/day). It was noted there was already substantial acidogenic activity in the landfill cell before the acidogenic reactor. Development of the microbial communities in the two reactors was influenced by the acidogenesis in the landfill cell. A COD half-life of 10 weeks was achieved in the pilot-scale landfill system indicating very fast organics stabilization in the landfill. It was shown that with an ex-situ anSBR augmenting treatment of the landfill leachate, rapid landfill stabilization could be achieved even when leachate recirculation was at a relatively low rate.