Preparation of Al_2O_3-SiC Composite Powder by Carbothermal Reduction of Coal Gangue and its Influence on Properties of Blast Furnace Stemming

摘要

Al_2O_3-SiC composite powders are prepared by carbothermal reduction method using coal gangue as raw material and carbonaceous materials (such as coke, anthracite, and carbon black) as reducing agents. The optimum conditions are as follows: when the addition of coke or anthraciteis 50%, the temperature is at 1600°C for 5 h, and adding 50% carbon black's best temperature is at 1600°C for 4 h. Based on the formula of stemming used in an iron and steel factory, Al_2O_3-SiC-C series blast furnace stemming refractory was prepared by adding Al_2O_3-SiC composite powder. The results show that the addition of Al_2O_3-SiC composite powders has a positive influence on the apparent porosity, volume density, and bending strength of the refractory. The effect of the amount of Al_2O_3-SiC composite powder on the slag corrosion resistance of the blast furnace stemming refractory was also studied by the static crucible method.