Characteristics of the mechanical stability and leachability of waste formwith plating sludge by reused polyethylene

The objective of this study was to investigate the effects of spent polyeth ylene (PE) addition on the mechanical stability and leachability bituminize d waste forms. The waste used for experiments was the actual sludge generat ed from an industrial plating factory and spent PE generated from an agricu ltural polyethylene film, respectively. The bitumen used in sample preparat ion is straight-run distillation bitumen, a paving asphalt. Bituminized was te forms with PE contents of 5 wt% or more resulted in maintaining dimensio nal and mechanical stability. The compressive strength and softening point of bituminized waste forms increase in proportion to the amount of spent PE . Moreover, the enhanced mechanical stability is possible to evaluate the b ituminized waste forms exactly. The precise leach test cannot be performed because of the deformation of the bituminous specimen. Leach test revealed that the principal leaching mechanism of metals(Zn, Cr, Cu) from bituminize d waste forms is diffusion.