Future technologies for energy-efficient iron and steel making

Techniques for the reduction of the specific energy consumption for iron an d steel making are identified and characterized to assess the potential for future energy-efficiency improvement and research and development prioriti es. Worldwide average specific energy consumption for steel making is estim ated to be 24 GJ/tonne. The most energy-efficient process requires 19 GJ/to nne for primary steel and 7 GJ/tonne for secondary steel. Seven specific sm elting reduction processes and four groups of near-net-shape casting techni ques are described and evaluated. In the longer term, the specific energy c onsumption for making steel from iron ore can be reduced to 12.5 GJ of prim ary steel per tonne. A further reduction of up to 2.5 GJ of crude steel per tonne may be achieved when techniques are developed that can recover and a pply heat from the hot steel at a high temperature. The specific energy con sumption for secondary steel making can be reduced to 3.5 GJ/tonne by energ y-efficient melting and shaping techniques.