The alumina content in the iron ore imported to Japan is increasing year by year, and some problems in blast furnace operation, due to the use of the high-alumina-containing sinter, have already been reported. In order to clarify the mechanism of the harmful effect of alumina on the blast furnace operation, the behavior of the primary melt, which is formed in the sinter at the cohesive zone of the blast furnace, has been simulated by dripping slag through an iron or oxide funnel. The effects of basicity, Al 2 O 3 , and Fe t O contents in the five slag systems on the dripping temperature and weight of slag remaining on the funnel have been discussed. It was found that the eutectic melt formed in the sinter would play an important role in the dripping behavior of the slag in the blast furnace through the fine poreosity of the reduced iron and ore particles. Al 2 O 3 increased the weight of the slag remaining on the funnel, and its effect became very significant in the acidic and low-Fe t Ocontaining slag. It was estimated that the increase of the weight of the slag remaining on the funnel by Al 2 O 3 in the ore could result in a harmful effect on the permeability resistance and an indirect reduction rate of the sinter in the blast furnace. MITSUTAKA HINO, Professor, and TETSUYA NAGASAKA, Associate Professor, are with the Department of Metallurgy, Graduate School slag melt from an iron or oxide funnel. The synthesized of Engineering, Tohoku University, Sendai 980-8579, Japan. AKITOSHI Fe t O-containing slag, which is assumed to be the primary KATSUMATA, formerly Graduate Student, Department of Metallurgy, melt, was heated and dripped from the funnel to simulate Graduate School of Engineering, Tohoku University, is Researcher, Research Laboratories, Nippon Yakin Kogyo Co. Ltd., Kawasaki 210-0823, the dripping behavior of the slag from the reduced metallic-Japan. KEN-ICHI HIGUCHI, Senior Researcher, and KAZUYOSHI iron or unreduced ore particles. The dripping temperature, YAMAGUCHI, Chief Researcher, are with the Ironmaking Process, Process the amount of slag remaining on the funnel, the composition
