| 摘要 |
PROBLEM TO BE SOLVED: To provide an operation method of a blast furnace making tuyere blowing of low quality coal with high volatile component and high ash content possible.SOLUTION: There is provided an operation method of a blast furnace for blowing low quality coal containing a volatile component of 30 mass% or more and an ash content of 12 mass% or more having a flame temperature in front of a tuyere of 2045°C and air ratio of the low quality coal of 0.73 or more. There is also provided an operation method of a blast furnace with melting capacity (M) of a cohesive zone root represented by the formula (1) of 13.5 or more. M=Tf×V/(h×V) (1), where Tf represents tuyere front temperature (°C), Vrepresents bosh gas amount (m/min), h represents furnace body ore layer thickness, and Vrepresents blast furnace volume (m). |
