1995 Volume 81 Issue 12 Pages 1114-1119
Hot model experiments were carried out to clarify the combustion behavior in the raceway and the gas flow changes nearby the raceway at the massive coal injection into the blast furnace. From the experimental results, it was found that the location of maximum temperature in the raceway agrees with the peak position of the CO2 gas composition and it tends to move toward the tuyere when the amount of volatile matter carried by the injected coal increases. The combustion efficiency was influenced by the volatile matter content of the injected coal and the oxygen enrichement had little effect on the combustion efficiency. The heat load to the wall of the hot model increased by the approach of the maximum temperature position toward the tuyere and it decreased by the reduction of ash content in the coal. It was observed that the shell layer was formed at the depth of the raceway. Then, it was estimated that the peripheral gas flow was intensified and the heat load to the wall increased due to the formation of the shell layer. These tendencies were confirmed by the mathematical simulation on the gas flow.
