| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the combustion efficiency of pulverized fine coal blown from a tuyere, to lower the fuel ratio in a blast furnace and to reduce the cost by forming the cross-sectional ration of an inner and an outer pipes in a burner for blowing the pulverized fine coal in a specific range and enlarging the contacting area between oxygen blown from the outer tube and the pulverized fine coal blown from the inner tube. SOLUTION: Conduit inner diameter of the cross section of the blowing hole for the pulverized fine coal at the tip part of the burner for blowing the pulverized fine coal is formed as smaller shape by at least >=10% than the diameter of a circle having the same cross section as this opening hole cross section. For example, the shape of this burner is to be formed as shown in the figure. These cross sectional shapes of the burner is be formed not only to its end surface but also over its whole length. By this constitution, the difference between the injection speed of the pulverized fine coal at the time of injecting from the tip part of the burner and the speed of the oxygen or the oxygen-enriched air surrounding the injection flux of the pulverized fine coal, becomes large to improve the combustion ratio of the pulverized fine coal.</p> |
