Since for upgradation of ore values, comminution is an essential and energy intensive process as well as the selection and capacity of the mill also depend on the grindability characteristics of ores, an attempt has been made to determine the work index of an ore using Bond's grindability method. This paper deals with the selected low-grade ores such as chromite, bauxite and graphite, which are distinctly different in physical and chemical characteristics and useful for refractory applications after upgradation of the crude ore by different mineral processing techniques. The test results conclude that the work index values of these ores vary from 10.5 ― 12.9 kWh/t only. This is further reduced to around 8 kWh/t by thermal pre-treatment. The relative saving in power by thermal pre-treatment achieved is 28%. Thus, it is observed that the power consumption does not vary significantly for grinding the ore to liberate the valuables from these crude ores. A reduction in the power consumption could also be achieved by thermal shock treatment.
展开▼
