Energy management

Energy plays an important role in the steel industry, which accounts for 4% of the world's total energy consumption. As a result, the steel industry is the world's biggest industrial energy consumer. It should be remembered, however, that theoretical requirements are relatively limited, since per tonne of iron (i.e., practically, per tonne of steel), the requirements are as follows:

• 1.350 GJ for melting at 1,600°C, which corresponds roughly to the melting of supposedly pure scrap metal;

• 6.520 GJ for reduction (from Fe ₂ O ₃ ) and melting.

In fact, per tonne of steel, industrial values are of the order of :

• 6 to 8 GJ for scrap-based mini-mills;

• from 17 to 20 GJ for integrated plants starting from ore, and aiming, by various means, for values of the order of 13 to 15 GJ.

This article will situate energy consumption for the various types of steelworks before indicating, on the one hand, how further savings could be made and, on the other, how energy is managed in steel companies and plants.