Treatment of landfill leachate using an up-flow anaerobic sludge semi-fixed filter

In the present work, an up-flow anaerobic sludge semi-fixed filter (UASSF) was developed for landfill leachate treatment by packing the soft polyurethane belt as the supporting carrier. The performance of the hybrid reactor was evaluated in terms of COD removal and carbon flux distribution, also, the biomass effectiveness was investigated by restarting the reactor without the supporting carrier. The COD removal increased with the stepwise increment of the organic loading rate (OLR), while the sulfate removal decreased slowly. When the reactor was operated at design load (9 kgCOD/m³·d), COD and sulfate removal remained around 81% and 90%, respectively. The results indicate that this kind of semi-fixed carrier is capable to form the active biofilm in the anaerobic process, and the UASSF system can perform well in the leachate treatment. (paper)