The effect of column dimensions and particle size on the results of kinetic column test used for acid mine drainage (AMD) prediction

Acid mine drainage (AMD) is known as one of the most important environmental problems of sulfide bearing rocks encountered worldwide. Several methods based on static and kinetic principles have been developed for estimation of AMD potential and determination of the contaminants concentration to the environment. Of these methods, kinetic column test is commonly performed due to its better representation of actual field conditions. However, the effect of main controlling factors such as column dimensions, the amount of material and its particle size on the results of kinetic column test were not investigated in detail. Considering the importance of AMD and the limitations in conjunction with these main controlling factors, the objective of this study is to investigate the mechanism of the AMD generation and to perform this test by using samples in varied particle size and columns in different dimensions. For this purpose, columns were designed in various dimensions and samples were collected from Murgul Damar open-pit mining to be used in the kinetic column test. Several techniques were utilized to determine the mineralogical, physical and/or chemical composition of these samples before and during kinetic column tests. The variations of the pH and the concentration release rates of many elements and compounds were monitored during kinetic column tests. Statistically significant correlations were obtained between column dimensions and 'lag time'. Similarly, it is determined that statistically significant correlations exist among column dimensions and cumulative mass release rates of SO4 and the Ca + Mg + Mn.