Preparing Fe-Cr-Ni alloy by utilization of limonitic nickel laterite sinter

Abstract

In this paper, sinter samples of limonitic nickel laterite were adopted for Fe-Cr-Ni alloy preparation at lower costs. Based on the thermodynamics analysis, smelting characteristics of sinter samples of S1 (4.84 wt% Cr₂O₃) and S3 (7.72 wt% Cr₂O₃) were revealed by the optimization of smelting process parameters. When smelting durations were kept at 60 min and 90 min for S1 and S3 and smelting temperature, coke dosage and slag basicity were maintained at 1600 °C, 20 wt% and 1.0, respectively, the qualified Fe-Cr-Ni alloys containing 84%–88 wt% Fe, 5.6%–9.3 wt% Cr and 1.55%–1.70 wt% Ni were prepared with the recovery rates of Fe, Cr and Ni of over 96%, 90% and 98%, respectively. Higher Cr₂O₃ content of sinter leads to the prolongation of smelting duration, which is adverse to the reduction of coke ratio and the increase of stainless steel output. The comprehensive furnace burdens including Ni-bearing sinter and Cr-bearing pellets will be developed in the follow-up study for the more efficient preparation of high-Cr ferronickel.