China Nonferrous Metallurgy

Considering low Ni recovery from the reduction product of high-Mg nickel laterite and difficult recovery of Ni from pyrrhotite, the oxidation roasting product of pyrrhotite was used as an additive to promote the migration and growth of ferronickel particles in the direct reduction of high-Mg nickel laterite and to improve the follow-up magnetic separation effect of ferronickel particles from roasting slag. The test results show that under the conditions that magnesian laterite containing 1.24% nickel and the oxidation roasting product of pyrrhotite containing 1.16% nickel are mixed at a mass ratio of 1∶6, with 6% reduced coal and 6% calcium fluoride added, for roasting at 1200℃ for 50min, followed by grinding and magnetic separation, the ferronickel product with Ni grade of 4.26% and Ni recovery of 91.85% can be obtained. By using this method, the comprehensive recovery and utilization of magnesian laterite and nickel-bearing pyrrhotite can realized and new ideas have been provided for fully utilization of refractory resources.