Influence of pellet quality on blast furnace results

The pellet ratio in the blast furnace burden is tending to increase compared with sinter. In Europe in particular, the discussion about pollution control has limited any further expansion of sinter capacity. Figure 1 shows that pellets today are about one third of the total ore burden, while lump ores are 12% and sinter more than 50%. Looking at the situation in several German blast furnace plants shows that they have very different pellet ratios (Figure 2). Plants with high sintering capacity such as TKS or HKM are using only small pellet quantities, while at Stahlwerke Bremen or Salzgitter the pellet input is much higher. The higher the pellet ratio in the burden the more important becomes a good and constant quality of pellets meaning the technological as well as chemical characteristics. [GRAPHICS] As there are many other factors influencing blast furnace performance, a definite relationship between pellet characteristics and blast furnace results is not always possible. in most cases the results can only be detected by statistical methods.