Development of injection of reduction gas into the blast furnace shaft

The injection of hot reducing gas into the shaft was investigated at Arcelor Eisenhüttenstadt. The blast furnace No. 1 (BF 1) was modified for the investigations with additional tuyeres at the BF shaft and the installation of hot gas generators (HGG). The hot reducing gas was generated by partial oxidation of natural gas with oxygen within 4 HGG and injected into a fourth of the total BF cross-section. First CFD calculations for prediction of expected penetration depth were carried out. The penetration depth during experimental reduction gas injection was determined by He tracing tests. The reduction degree of the burden material was determined by core drilling exercises and analysis of the core material. The investigation shows, that the gas injection into the shaft seems to be a key technology to raise the use of additional reductants for the blast furnace process and to become more flexible in reductant application