Investigation of the ability of chrome concentrate from chrome enrichment plant wastes

The aim of this study is to investigate the possibility of obtaining salable Chromite concentrate from Chromite enrichment plant wastes. Chromite enrichment processes are carried out commercially by gravity methods. However, gravity methods are not effective in the enrichment of fine-grained ores. Fines are mostly stored in landfills together with plant waste. In this study, the efficiency of the flotation method was investigated to obtain chromite concentrate from the waste stored in the tailings dam. Samples taken from the tailings dam were subjected to particle liberation analysis (MLA) to determine the degree of liberation. In order to determine the effective flotation conditions, the results of the preliminary experiments with different collectors and depressants in basic and acidic environments were compared and the systematic flotation conditions and the levels of the parameters that were effective in the separation were determined. During the preliminary experiments, it was determined that the slime had negative effects on selectivity. For this reason, slime removal process was applied to remove the existing fine part in the sample. Again, in preliminary tests, it was observed that dilute sulfuric acid leaching had positive effects on the grade and yield of the concentrate. Therefore, the sample was subjected to sulfuric acid leaching before flotation. Flotation experiments were carried out at pH 10.5 using 1000 g/t, 1:1 ratio of SM 15 + SM 35 collector mixture and 800 g/t Na2SiO3 as dispersant. "Central Composite Design (CCD)", one of the statistical design methods, has been applied in the planning of experimental studies, evaluation of results and creation of model equations. Design Expert 11 version was used for analysis of variance and creation of model equations. In the most suitable experimental conditions; A salable chromite concentrate was obtained from waste with 43.30% Cr2O3 grade and 88.62% yield.