Long-term leaching and volatilization behavior of stabilized and solidified mercury metal waste

With the signing of the Minamata Convention, widespread disposal of mercury metal waste is anticipated in the near future. Due to its environmental effects, mercury metal waste must be stabilized prior to disposal as its mercuric sulfide form and/or solidified with a polymer or cement to reduce leaching and volatilization. This study investigates the long-term leaching and volatilization behaviors from processed mercury waste. Mercury metal waste specimens are stabilized with sulfide and subsequently solidified with either a sulfur polymer or one of three types of low-alkaline cement. The long-term leaching rates from the solidified mercury metal waste specimens as well as the effects of pH and temperature on leaching behavior are evaluated. The long-term volatilization rates of gaseous mercury are also calculated at different temperatures. Mathematical models for mercury leaching, volatilization rates, and their parameters are established to predict the long-term behavior of stabilized, solidified waste mercury in landfill sites.