Numerical Simulations of Leaching and Volatilization Behaviors from Stabilized and Solidified Mercury Metal Waste in Landfill

Abstract

This study investigates the environmental safety of landfill sites in which mercury metal waste is disposed. Serial batch tests were conducted to evaluate the long-term leaching and volatilization rates of mercury waste stabilized in its sulfide form, and solidified using either a sulfur polymer or two different types of low-alkaline cement. Using measured mercury leaching and volatilization rates, numerical simulations were conducted to investigate the long-term behavior of mercury after its disposal in landfill sites. For leaching behavior, the concentration profiles of dissolved mercury accumulating in a drainage pipe at the bottom of a landfill site were calculated, while volatilization behavior was assessed by analyzing the gaseous mercury emissions from the final cover surface. The effects of covering the disposed mercury waste with either soil sorption layers or cut-off layers were evaluated through analysis of the calculated concentration profiles.