| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for operating a blast furnace, which can prevent the furnace from falling in a bad condition during a low RAR operation, particularly can prevent poor heating for a charged material in the upper part of the furnace, when operating a normal blast furnace, and can stably lower the raw material without causing the fluidization or agitation of a charged layer of the raw material due to the blowing of a gas from a shaft portion. <P>SOLUTION: The method for operating the blast furnace includes: providing a gas-blowing portion (A) between a position p<SB>1</SB>and a position p<SB>2</SB>in the furnace height direction, when representing the radius of the furnace port of the blast furnace by R<SB>0</SB>, the position at which the depth from a stock line is R<SB>0</SB>by p<SB>1</SB>, and the position at which the height from the lower end of the shaft portion is 1/3 of the total height of the shaft portion by p<SB>2</SB>; blowing a hot blast having an oxygen-enriched rate of 20% or less by volume into the furnace from a tuyere; and blowing a preheated gas from the preheated-gas-blowing portion (A). <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
