Direct reduction of iron ore using wood as fuel - in rotary ovens, with utilisation of the total calorific value

摘要

Iron ore is reduced directly to spongy iron by use of wood as fuel and reducing agent, in a rotary tubular oven, a mixt. of ore and wood being fed in at the upper end. Energy content of the wood, including the gas and volatiles evolved, is fully utilised, so that only 1000kg. wood per tonne iron is required, cf. 460 kg charcoal from >=2000 kg. wood. Reduction commences and proceeds at a lower temp. than with anthracite or coke, the discharge temp. being 850-950 degrees C against almot 1100 degrees C.