Effect of Clay Minerals on the Flotation Performance of Coal and Mean Bubble Size

Flotation is one of the most effective methods used in the enrichment of fine sized coals. However, the presence of clay minerals as gangue minerals in coal affects the flotation process negatively. In this study, the effects of clay minerals (kaolinite and montmorillonite) and flotation reagents on the flotation performance and mean bubble size of Tun & ccedil;bilek lignite coal were investigated. In the experimental studies; sodium silicate was used as depressant, kerosene was used as collector, methyl isobutyl carbinol (MIBC) and Dowfroth 250 were used as frother. Clay type and amount, depressant amount and frother type and amount were the experimental parameters studied. In experimental studies in which the effect of depressant amount and clay content was determined, combustible recovery values were obtained in the range of 40-55% for samples containing kaolinite and 30-47% for samples containing montmorillonite. Better results were obtained with Dowfroth 250 as the frother, and the coal sample containing montmorillonite caused larger bubbles to form than the coal sample containing kaolinite. The results obtained from this study will form a basic infrastructure to understand the flotation behavior of coals containing clay minerals as gangue and to offer solutions.