Characteristics of Qingxu coal applied in the 4 350 m^3 blast furnace of Taigang

The characteristics of cheaper Qingxu coal were investigated in Taigang of China. It was discussed that Gaoping anthracite and Lu'an lean coal are replaced by cheaper Qingxu coal. Twelve performance tests of Qingxu coal were carried out. The results show that Qingxu coal has such virtues as a better combustion property and reactivity, a higher heat value and ash fusibility, good fluid-ly and non-explosiveness at the same time. Conversely the S content is higher in Qingxu coal, and the Zn content is lower in the washed Qingxu coal but higher in the unwashed Qingxu coal. The blast furnace injection standard can be achieved by mixing the coal. The analysis of FactSage software illustrates the reason that the tuyeres are jammed by slagging when Qingxu coal is used excessively. Laboratory studies and field results show that Qingxu coal can be injected into the blast furnace by coal blending, but the substitution rate of Qingxu coaI should be to less than 20%.