Response Surface Methodology for Optimization of the Chloridizing Roasting Process for a High Copper Pyrite Cinder

摘要

This study aimed to obtain volatile copper from a high-copper pyrite cinder by optimizing the chloridizing roasting process using response surface methodology (RSM). The effect of key parameters, i.e., dosage of CaCl_2 addition, roasting time and roasting temperature, on the copper volatile ratio was investigated and a quadratic model was suggested by the methodology to correlate the variables to this volatile ratio. The results indicated that the model was in good agreement with the experimental data at a correlation coefficient (R~2) of 0.9782, and the most influential parameter on efficiency was identified as the dosage of CaCl_2 addition. The optimum conditions for chloridizing roasting from the high copper pyrite cinder were identified as a dosage of CaCl_2 addition of 4.8 wt%, a roasting time of 19.28 min and a roasting temperature of 1151.51 °C; under such conditions, a copper volatile ratio of 97.82% was achieved. The pellets obtained by this process are characterized by a high content of hematite, and the main impurity element contents are consistent with the requirements for iron concentrate, which is suitable for use in ironmaking.