PULVERIZED COAL INJECTION METHOD

PROBLEM TO BE SOLVED: To provide a pulverized coal injection method in which a change of the particle size distribution of pulverized coal with time is accurately measured to allow suitable injection of the pulverized coal.SOLUTION: The pulverized coal injection method uses a pulverized coal injection apparatus, in which the pulverized coal produced by grinding coal with a pulverized coal production apparatus 16 is transported by air flow to a bag filter 7; the pulverized coal collected in the bag filter 7 is stored in a coal bin 8; and the pulverized coal stored in the coal bin 8 is taken out into an injection tank 9 and transported by air flow towards a blast furnace tuyere 13. The method includes: a particle size distribution-measuring step of taking out the pulverized coal produced in the pulverized coal production apparatus 16 from a transport path and periodically measuring it with a particle size distribution measuring device 40; and a grinding force-adjusting step of adjusting the coal grinding force in the pulverized coal production apparatus 16 using a deviation between a measured value and a targeted value measured in the particle size distribution measuring step. The particle size distribution-measuring step includes using a particle size distribution-measuring device 40 in which the standard deviation of the measured values of a standard sample is within 1%.