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Ferronickel enrichment and extraction from nickel laterite ore were studied through reduction and magnetic separation. Reduction experiments were performed using hydrogen and carbon monoxide as reductants at different temperatures (700–1000°C). Magnetic separation of the reduced products was conducted using a SLon-100 cycle pulsating magnetic separator (1.2 T). Composition analysis indicates that the nickel laterite ore contains a total iron content of 22.50wt% and a total nickel content of 1.91wt%. Its mineral composition mainly consists of serpentine, hortonolite, and goethite. During the reduction process, the grade of nickel and iron in the products increases with increasing reduction temperature. Although a higher temperature is more favorable for reduction, the temperature exceeding 1000°C results in sintering of the products, preventing magnetic separation. After magnetic separation, the maximum total nickel and iron concentrations are 5.43wt% and 56.86wt%, and the corresponding recovery rates are 84.38% and 53.76%, respectively.

According to the analysis of iron element purification in the current process of steel production and the study on reduction experiment of ultrafine iron ore powder, this study first summarizes and puts forward the scale effect on reduction of iron oxide. And on this basis, a new concept is proposed, named precise reduction, which includes the pre-processing—dissociation of iron oxide, preparation of ultrafine powder and the post processing—non-molten magnetic separation. Taking high phosphorus hematite, steelmaking slag and metallurgical dust as the study objects, and the better achievement shows that the low grade iron-bearing material, after precise reduction, can be transformed to the valuable resource without residue, and the process is environment friendly with low energy and material consumption, so that the zero discharge can be achieved. Not only does the steel plant be changed to be environment friendly, but also the resource is got.