PURPOSE: To control dropping behavior of charged material and to stably operate a blast furnace by positively making irregularity of inner wall surface shape contrary to what the irregularity has problem for the suitable operation in the blast furnace, and adjusting this irregularity.
CONSTITUTION: Along the circular direction at shaft lower part, belley part and bosh part in the blast furnace, protruding materials 1 in which advancing retreating in horizontal direction toward furnace center can be independently adjusted at every ranges divided into plural number in furnace height direction are set. Then, protruded length of each protruding material 1 is independently adjusted at each range divided into plural number in the furnace height direction (to the circular direction at the same time). By this method, dropping velocity of charged material, heat flow ratio and profile on operating face, which the charged material drops, near the furnace wall in the optional range divided into plural number in the furnace height direction from the shaft lower part to the bosh part, can be controlled. Then, at the time of forming stagnated layer, it has possibility that stuck material grows and in the case of showing this sign, after setting fuel ratio to higher, the stuck material can be fallen down by inserting the protruding material 1.