Determination of Work Index of Muro Iron Ore Using Marble and Granite as Reference Ores

Abstract

The work index of Muro iron ore was determined using the modified Bond’s method also known as Berry and Bruce method. This study used iron ore obtained from Muro town, a community in Toto LGA, Nasarawa state as the test ore. Marble and Granite which was separately used as the reference ores were obtained from Muro environs. 100 g each of the test ore and the reference ores were subjected to the same grinding conditions in a ball mill. Size analysis of the feed to the ball mill and the product of the ball mill for both test ore and reference ores were carried out and the results tabulated accordingly. The 80% passing particle size of the ball mill feed and discharge for the samples were calculated using the Gaudian Schumann expression. The Bond’s equation was then used to calculate the work index of the Muro iron ore which was found to be 24.84 kWh/ t when marble was used as reference ore and 27.41 kWh/ t when granite was used as reference ore. The average work index of Muro iron ore was calculated as 26.13 kWh/ t, while the energy requirement for grinding the ore was found to be 3.62 kWh/ t. The value of the work index of Muro iron ore is within the limit of work index of iron ore quoted in literatures