Test on Comprehensive Recovery of Chromium from a Foreign Nickel-cobalt Ore

A foreign nickel-cobalt ore contains 1.10% nickel and 0.11% cobalt, which mainly exists in cryptocrystalline clay minerals in the form of ion adsorption. The ore contains 3.96% Cr₂O₃, and chromium basically exists in the form of chromite, which has the value of comprehensive recovery. In view of the high content of nickel and cobalt in the ore, and in clay minerals in the form of adsorption, clay minerals are easily sloughed during the grinding process, resulting in nickel and cobalt are enriched to the fine particle level and chromium basically exists in the form of chromite. During the grinding process, chromite particles of varying sizes are produced. Combined with the characteristics of relatively large gravity, the technical idea of grading and classifying after ore grinding, recovery of coarse-grained chromite by gravity separation, and recovery of fine-grained chromite by flotation is proposed adopting the process of "cyclone classification - spiral chute roughing - shaking table cleaning - shaking table tailings flotation" and selecting high-efficiency chromite collector GC to enhance the recovery of fine-grained chromite. The results of the whole process study show that chromite concentrate with Cr₂O₃ grade of 46.30% and Cr₂O₃ recovery rate of 71.95% can be obtained. At the same time, the nickel-cobalt slurry with Cr₂O₃ content of only 1.16% was obtained, creating favorable conditions for subsequent metallurgical recovery of nickel-cobalt.