An investigation of the process of production of reducing agent for ferroalloy production in a ring oven

Reactivity, resistivity and size consist of carbon reductants are largely a function of the heating rate end temperature of the charge, both of which can be closely controlled and modified in the ring oven with its revolving hearth. These factors were statistically modelled using charges of 25-10mm and 40-25 mm, and revealed wide fluctuation in end properties, e.g. resistivity ranging from 2.88 to 0.067 ohm.cm. Charge size consist has a decisive effect on the size distribution of the solid residue, reflecting the interplay between cakeability and the destructive forces resulting from thermal and shrinkage stresses. Regression analysis produced an optimized reductant from a gas coal charge whose resistivity of 18-23 ohm.cm compared with conventional metallurgical coke at 3.45 ohm.cm, and with increased reactivity and much larger specific internal porosity. Greatly improved reduction figures were obtained when treating manganese and silicon in particular accompanied by a much faster process.