An investigation into the effect of various parameters on oil agglomeration process of coal fines

In the present study, the authors have performed oil agglomeration of coal fines using castor oil and combination of castor oil and turpentine oil in various proportions. The coal samples were collected from three different mines of Mahanadi Coalfields Limited having high ash content (27-39%). From the post proximate analysis it was revealed that in case of Mine 1 coal, the moisture content reduced by 83%, for Mine 2 it was 94% and for Mine 3 the moisture reduced by 90% from the initial values. Grade achieved after oil agglomeration process was G5 grade for Mine 2 coal and G3 grade for Mine 1 & 2 coal. The effect of various parameters such as oil dosage, pulp density, pH, on yield, ash rejection and organic matter recovery were studied. The parameter with the highest relative importance was found to be oil dosage (normalized importance of 100%) whereas agitation time and pulp density were found to have normalized relative importance of 74% and 70%, respectively. A non-linear regression model in the form of quadratic equation has also been proposed for ash rejection (%) based on the independent variables such as pulp density, oil dosage and agitation time.