Investigation on reduction of cement binder in cold bonded pelletization of iron ore fines

Cold bonded pelletization processes developed for utilization of iron ore fines and slimes require about 10% or more cementitious binders. Reduction of the cost of the pellet and its gangue content require reduction of the amount of binder. This communication reports the results of an investigation on reduction of binder requirement in cold bonded pelletization of iron ore fines by using cement clinker alone or mixed with silica of different characteristics. Pellets with crushing strength of 100-200 kg/pellet could be obtained even using about 4-6% binders consisting of Portland cement clinker/cement of appropriate chemical characteristics and fineness either alone or mixed with silica fines. The binder requirement may be curtailed by about 4% by increasing its surface area. The physico-metallurgical properties of the cured pellets indicate potentiality for use as burden material in low/moderate shaft furnaces.