Landfill bioreactor is a modified technique comparing with the conventional landfill processes due to its ability to reduce time for decomposition and enhancing the biogas generation. The basic goal of this paper is to investigate the performance of a three lab-scale bioreactors under anaerobic conditions. Three types of reactors differ in its internal composition were experimented ,bentonite clay was used as a cover material. First reactor was filled with organic solid waste only; second reactor was filled with a mixture of organic solid waste, Lime and sawdust, while the third reactor was filled with mixture of solid waste and lime. Leachate characteristics traced includes pH, EC, TDS, TSS, Heavy metals (Cr, Fe, Mn, Zn, and Mo), Sulfate SO-24 and Phosphate PO-34.
Experiments were conducted from October 2014 to march 2015, Results shows a significant variation in removal efficiency for each reactor, heavy metals removal for the first reactor was (Mn 58.6%, Cr 13.4%, Mo 0%, Zn 27.2%, Fe 58.6%),and the second reactor removal efficiency was (Mn 77.2%, Cr 67.5%, Mo 69.19%, Zn 67.9%, Fe 56.7%), while for the third reactor was (Mn 30.1%, Cr 13.8%, Mo 18.48%, Zn 29.8%, Fe 70%). The results show that the solid waste, Lime and sawdust enhanced the removal of heavy metals in the 2nd reactor which gave best removal efficiency for heavy metals. While the lime addition in the 3rd reactor increase the removal efficiency of iron to 70%. It can be conclude that this modified landfill bioreactor enhance leachate characteristics and so enhancing the solid waste stabilization.