Samples, which were analyzed in the Master thesis, were obtained during the exploration campaign in the Southwest of Ivory Coast. Main purpose of the research was exploration for new sources of columbite-tantalite (COLTAN) and other heavy minerals, resulting in excavating 25 exploration pits. Gravity and magnetic separations experiments were performed on samples from the exploration pit P13. During gravity and magnetic separation procedures, a total number of 106 samples was collected. These samples were analyzed via laser granulometry (2 samples), XRF (81 samples), XRD (16 samples) and SEM-EDS (2 samples). The main purpose of this thesis is to prove that, by using a combination of methods, we can achieve high levels of recovery and high quality concentrates during the processing of laterite samples from the Ivory Coast.
Granulometric analysis of samples, which were collected during the gravity separation experiment performed on a Multi Gravity Separator, revealed that sieved samples with grain size ‒63+45 μm disintegrate during homogenization which negatively affected conditions for separation. We tried to reach optimum conditions by trying to pre- concentrate the input material in a bucket and water columns. Thereby we reached a 78,7 % recovery rate for Zr. The separation experiment on spirals was performed in four phases, so that we started testing the two smaller fractions (⠒250+125 μm and ⠒500+250 μm) and then continued by adding bigger fraction grains in size ⠒2 mm+500 μm. Results have shown that by adding bigger grains we reduced Zr recovery in the concentrate. In that experiment, the maximum recovery rate of 15,8 % for Zr was reached with narrow graded material from fraction ⠒250+125 μm. Underflow product of the dynamic separation experiment in tall water column was used in further testing on the magnetic separator Sala HGMS. Results have shown minimum differences in enrichment of the concentrate and tailings. Reasons for that are probably low grain liberation as well as the effect of residual magnetism, resulting from the material being magnetized, despite the strength of the magnetic field being reduced to zero. XRD results have shown that the main mineral phases in most samples that were analyzed are quartz, kaolinite and muscovite. The last three samples (P13_096⠒098) which consist mainly from hematite, ilmenite and rutile, are an exception. SEM-EDS results for two analyzed samples revealed that the first sample (P13_059) consists predominantly of quartz while the second one (P13_098) consists predominantly of ilmenite.
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