Multiobjective collaborative optimization of novel carbothermal reduction process of stainless steel dust and laterite nickel ore

Abstract

By using the central composite design based on the response surface method, the multiobjective collaborative optimization of Fe, Cr and Ni metal recovery from stainless steel dust and laterite nickel ore was achieved through carbothermal reduction, and a high metal recovery rate and high-grade Fe-Cr-Ni-C alloy particles were obtained. The addition of laterite nickel ore and reduction temperature exert significant effects on the metal recovery, and a significant interaction is observed among the recoveries of the metals Fe, Cr and Ni in the reduction products. The optimal process parameters obtained through the optimization of the model are listed as follows: the amount of added laterite nickel ore is 5.47%, the reduction temperature is 1428.02 °C, the reduction time is 23.10 min, and the carbon oxygen ratio (FC/O) is 0.85. The predicted results for Fe, Cr and Ni recovery using the model are 93.15%, 91.63% and 92.70%, respectively.