Liberation studies of low grade copper ore from Kallur, Raichur district, Karnataka, IndiaAuthor(s): R.Purushottam Reddy, R.N.Raghavendra, R.Nijagunappa
Copper, an important non-ferrous metal, is in great demand in India, resulting in a continuous import of large quantities. The development and exploitation of new reserves assumes importance in order to meet the increasing demand from internal production rather than through imports of the metal. Minerographic study indicates the presence Chalcopyrite, Pyrite and Specularite are the chief oreminerals associated withQuartz, Feldspar, Calcite and Hornblende as gangue minerals. For ore beneficiation, it is necessary to know the mesh size at which the ore minerals are liberated from the gangue minerals thereby controlling the grinding limit for good separation. The liberation studies of different sieve fractions indicating the extent of free and locked mineral particle in each fraction. The experimental results show a total liberation of 86.32% of all mineral at -150+200 mesh. In this paper, the liberation of Chalcopyrite at -150+200 mesh is 73.42%and average cumulative liberation for those minerals at -150 meshes can be theoretically expected to be 81.50%. Hence -150meshes is chosen as the theoretical mesh of grind for the ore at which size the smallest grain of chalcopyrite would have been reduced 10 times for good liberation of the mineral.