Understanding the Mechanism of Arsenic Mobilisation and Behaviour in Tailings Dams

Abstract

This study was carried out on leaching of tailings at 30 ᵒC and 40 ᵒC. The mineralogical and chemical composition of the tailings material were determined by Quantitative X-Ray Diffractometry (QXRD) and Scanning Electron Microscopy combined with Energy Dispersive Spectroscopy (SEM-EDAX). The study revealed that the tailings contain sulphides (arsenopyrite and pyrite) which can leach to produce arsenic (As) and other ions in solution. The acid released during leaching depends on the temperature of leaching. More acid was produced at higher temperature (40 ᵒC) than lower temperature (30 ᵒC). It was established that arsenic precipitation from solution was higher at higher temperature (40 ᵒC) than lower temperature (30 ᵒC). Mimicking the study in a typical tailings environment, it could be proposed that As mobilisation will be enhanced at lower temperature (30 ᵒC) than at higher temperature (40 ᵒC). Keywords: Tailings, Leaching, Arsenopyrite, Heavy metals and Temperature

Anthropogenic Sources and Risk Assessment of Heavy Metals in Mine Soils: A Case Study of Bontesso in Amansie West District of Ghana

“…Te mining processing procedures utilized largely determine the extent of the damage [2], and without appropriate management, precipitation washes out tailings, which serve as a source of heavy metals contamination and could lead to ecological problems [3]. Tese environmental problems associated with mining activities, such as pollution and land degradation, have been emphasized in several studies in Ghana [4][5][6][7].…”