METHOD FOR BLOWING PULVERIZED COAL TO BLAST FURNACE

PURPOSE:To attain a sufficient mixing state of hot wind and pulverized coal even with one piece of pulverized coal blowing lance and to exceedingly improve the combustion rate of the pulverized coal by forming the projections to be provided on the inside surface of a tuyere or blow pipes to a spiral or V shape. CONSTITUTION:The projections 6 having the spiral or V shape or further the combined shapes thereof are provided on the inside surface of the tuyere 1 and/or the blow pipe and the pulverized coal blowing lance 3 is so disposed that a mixed phase flow 4 composed of the pulverized coal and the carrier gas thereof comes into contact with the projections 6. The flow along the projections 6 is, therefore, formed, in addition to the axial flow of the hot wind 8, in the tuyere or the blow pipe. The mixed phase flow 4 is mainly intruded into the flow of the hot wind 8 along the projections 6 and while a part thereof is released as shown in Fig., the mixed phase flow moves along the projections 6. Consequently, the pulverized coal is dispersed into the outer peripheral part where the quantity of the hot wind flowing in the tuyere or the blow pipe is large. The combustion rate is thus exceedingly improved.