ABSTRACT
A process route for the beneficiation of Mallam Ayuba Manganese deposit located in Kaduna State, Nigeria was developed. By this route a low grade manganese concentrate which can be used in the production of spiegeleisen using the blast furnace process was produced. Based on the chemical, size/assay and mineralogical analyses carried out in this study, it was established that Mallam Ayuba Manganese deposit is a low grade ore containing only 23%Mn304 with high amoaunt of Si02 (38.68%). The deposit also contains moderate amount of sulphur (0.01%) and phosphorous (P2O5) (0.49%). From these analyses it was also established that the constituent minerals of the ore, are uniformly distributed, finely dessiminated and intermittently associated with each other. Liberation and grindability tests, revealed that no meaningful degree of liberation could be achieved because of the high degree of interlocking and intergrowth between the individual mineral grains. These tests also gave the average work index of the ore over particle size range -75 to -lOOOuM to be 13.12kwh/st. Concentration tests by gravity and froth flotation techniques with the aim of producing a concentrate for ferromanganese production did not yield the desired results. This is because the concentrates produced assay low manganese and high Si02 However, a low grade concentrate which can be used in the production of spiegeleisen(low grade ferromanganese) was produced by the process of lime-clinkering .This low grade concentrate can also be smelted with the Itakpe iron ore concentrate to produce a high manganese pig iron.