Coke plays vital roles in the ironmaking blast furnace process. It is the furnace fuel for the high temperature process and the primary source of CO gas for the reduction of iron oxide to metal. It is also an important material in maintaining the furnace permeability required for the high production rates1. The behavior of coke in the blast furnace is related to its hot strength and reactivity2. Therefore, to understand the coke behavior in the blast furnace, coke reactivity in the blast furnace should be well understood.