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 grooves orthogonal or spiral with the axis of a tuyere or blow pipe on the inside surface of the tuyere or the blow pipes. CONSTITUTION:The grooves 9 orthogonal or spiral with the axis of the tuyere 1 (or blow pipe 2) are provided on the inside surface of the tuyere or the blow pipe. The pulverized coal blowing lance 3 is so disposed that the main flow of a flow mixture 4 composed of the pulverized coal and the carrier gas thereof flows along the grooves 9. While the hot wind 6 flows at a high velocity in the tuyere, the mixed phase flow 4 of the pulverized coal and carrier gas blown from the lance 3 is moved along the grooves 9 while a part thereof is released as shown in Fig. with substantially no influence of the hot wind of the high flow velocity by providing the grooves 9. 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.