Leaching Properties of Secondary Lead Slag Stabilized/Solidified with Cement and Selected Additives

Abstract

Sodium lead slag, generated during secondary lead production, is characterized as hazardous waste. The aim of the study was to investigate leaching mechanism and behaviour of lead and arsenic from sodium lead slag previously stabilized/solidified in concrete using additives: MgO, CaO, Ba(OH)(2) and gypsum. The influence of selected additives on pollutant release was also investigated. The results of the NEN 7375 leaching test indicate dissolution of lead and arsenic from the outer layer of specimens, followed by depletion of possible mobile forms. Analysis of leachates from samples with various compositions showed that proper selection of additives may reduce leaching of Pb and As below the specified limits.