Bulk breakage mechanism of coke in lower part of blast furnace

摘要

In order to clarify the bulk breakage mechanism of coke in the lower part of blast furnace, model experiments were conducted based on the conditions that were possible to occur in the above region by considering the reaction form, reaction temperature, reaction degree and impact energy with 6 kinds of 50～100 mm diameter coke having different strength and reactivity. In the above region, the bulk breakage of coke is occurred nearly independent of CO{sub}2 gasification and seems to be controlled by the pore partition thickness in coke lump. The coke diameter reduction in the above region is decided both by the bulk breakage and the fine generation with abrasion accompanied by 20mass% CO{sub}2 gasification. The former effect is larger and the diameter reduction with bulk breakage of coke having 100～70mm diameter is greater than that of coke having 50mm diameter. The control technology of pore partition thickness in coke lump will be expected to be researched from now on.