Settling Study of Refuse Coal Fines: Performance Analysis Using Full Factorial Statistical Design Methodology

Full factorial design of experiment was employed to evaluate the effect of variables on the settling performance of coal fine. Influence of the variable parameters was discussed using 2D surface plots. Settling rate and turbidity were more sensitive to the flocculant dosage followed by the pH and the feed density. Highest settling rate of 190 mm/min was obtained with turbidity of supernatant liquid as 9 NTU at flocculant dosage of about 26 gpt and pH 9. Coefficient of correlation (R2) between the experimental and the predicted settling rate and the turbidity were found to be as 0.96 and 0.93 respectively.