Study On Properties Of Pulverized Coal Injected To Han Steel BF

At present, the condition is that injection coal complete is anthracite in Han Steel. Because the burning result of anthracite is second-rate than bituminite, limit the injection proportion to improve. For exert the virtue of anthracite and anthracite, on the base of laboratory, have make sure the proper variety of coal and the rational scheme of injection proportion for the BF of Han Steel.In the laboratory, physical and chemical character of coal have been tested, such as industrial analysis, constant volume net calorific power, elementary analysis, plastometer indice, ash composition, grindablity, ash fusion point, reactivity, explosiveness, flare point, combustion and transportation performance . It is according to the quality requirements of the coal for injection in BF and the practical production condition of the BF of Han Steel, the Dawan coal is the first choice for injection as bituminite, the Zhunlian coal is the better stand-by one, and the Changzhi coal is the first choice as anthracite, the Gaoping and Zezhou coal are the better stand-by ones.Increasing the proportion of bituminite in the mixed pulverized coal, which can improve combustion process, improve the transportation performance and increase the reactivity of the unburned pulverized coal in the BF. Changzhi coal and Dawan coal have the highest burning rate in all kinds mixed coal, Gaoping coal and Laozhanggou coal have the lowest burning rate .So the mixture of Changzhi coal and Dawan coal is the most suitable for inject to Han Steel blast furnace.The burning rate of pulverized coal and the micro-components have great relationship. Investigated indicate, Micro change coal, anisotropic structure, massive structure, broken massive, big pores, small pores, and burning of residual organic matter in the UPC, mainly from the vitrinite of coal; fissures structure and skeleton structure are mainly come from the fusinoid group; the ash in the coal mainly come from the minerals. Vitrinite is the main sources of UPC in a blast furnace. when the injection of pulverized coal in vitrinite content of 35%, fusinoid group content around 60%, the injection of pulverized coal burning rate have the highest value.The pyrolysis process of TG—FTIR experimentation show that, the pyrolysis process can be divided into four stages, when the primary pyrolytic reaction occurs in the range of 430~650℃. Mix coal could promote pyrogenation gas come out earlier and extend the release time.