For the purpose of utilization of the residual oil as a new energy resource for ironmaking, the development of an injection technique of petroleum coke-oil slurry into a blast furnace was undertaken. The slurry injection test through 4 tuyeres of No. 1 blast furnace at the Kobe Works was carried out for about 4 months. At the same time, the development of probe at the tuyere level was undertaken to study the combustibility of the slurry in the raceway. The petroleum cokes used in this study were the delayed coke (DC) and the fluid coke(FC).
As a result, it was confirmed that gas sampling, unburnt fuel sampling, and temperature measurement in the raceway were possible, and that the combustibility of the slurry could be evaluated on the basis of these results. It was made clear that the combustibility became worse in the following order, heavy oil, DC-slurry, and FC-slurry. However, the slurry injecton had no harmful influence on blast furnace performance. The replacement ratio of coke/slurry was about 1.0. Consequently, it was concluded that the slurry could be used as a substitute fuel for heavy oil.