The Research Of Reaction Mechanism Of Ferro-coke Gasification

To reach the goal of energy conservation and emission reduction, it’s necessary for iron and steel enterprises to develop ironmaking and coking technologies that are resource saving and environmental friendly. So the study of ferro-coke with high reactivity causes attention in ironmaking world. However, there are just few studies about ferro-coke produced in a common coke oven chamber, and the properties of the ferro-coke are not that satisfied.Thus, in this paper, to produce the ferro-coke with property suitable for blast furnace, ferro-cokes were produced in coke oven chamber by adding iron ore powders into cokemaking coal blend, then the influence of iron ore as well as coking process on ferro-coke properties were investigated, the mechanism of which were studied from microscopic view. The results are as follows:among ferro-cokes with Canadian iron ore addition, Australian FMG fine ore addition and E’xi high-phosphorus iron ore addition, the one with Canadian iron ore addition has high reactivity and proper strength, and the addition ratio should not exceed15%. Besides, when the addition ratio of Canadian iron ore is10%, for producing ferro-coke with good property, the bulk density is suggested to be1.0t/m3, the size distribution of Canadian iron ore should be less than0.2mm, the banking time should be150min, the heating speed should be0.25℃/min, and the blending ratio of gas-fat coal should not exceed10%.Additionally, the gasification reaction behavior of ferro-coke was studied by instantaneously recording the CO content in exhaust gas and coke sample weight loss with the self-made experimental apparatus. It is suggested that both the gasification reaction beginning temperature and activation energy of ferro-coke are lower than those of conventional coke, and these two values decrease with the blending ratio of iron ore powder increasing. Furthermore, the gasification reaction of ferro-coke in100%CO2atmosphere can be explained by unreacted core model, and the controlling mechanism is chemical reaction in boundary film.