M. Moazemi; B. Rezai; A. Amini
Abstract
In this research firstly ore characterization studies from ore dressing point of view have been conducted and then increase in module ratio i.e. ratio of Al2O3 to SiO2 of the bauxite samples from Boolboolieh area of Kerman province investigated by the means of ore dressing techniques. Obtained ...
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In this research firstly ore characterization studies from ore dressing point of view have been conducted and then increase in module ratio i.e. ratio of Al2O3 to SiO2 of the bauxite samples from Boolboolieh area of Kerman province investigated by the means of ore dressing techniques. Obtained results from ore characterization studies revealed diaspore and hematite were major mineral phases and Al2O3, Fe2O3 and SiO2 contents of head sample were 36.6, 27.02 and 20.32 % respectively and consequently module ratio was determined to be 1.8. Mineralogical studies on all prepared microscopic sections show clastic texture that contains pisolith and oolith particles inside microcrystalline matrix formed from hematite, clay minerals and fine bauxite particles. In ore dressing studies, physical separation methods, selective grinding, heavy media separation and tabling have been investigated. Obtained results from selective grinding revealed that alumina to silica ratio increases from 1.8 to 1.91 with alumina recovery about 69.3 %. Heavy Liquid separation tests proved that alumina to silica ratio increases to 3.32 with 64.02% alumina recovery by adjusting heavy liquid density to 3.22. Tabling tests approved increase in concentrate module ratio to 2.64 with reduction in alumina recovery to 21%.
M. Moazemi Goodarzi; B. Rezaei; A. Amini
Abstract
In this paper, iron removal studies on high iron diasporic bauxite by thermochemical treatment was investigated for the first time. For this purpose, bauxite samples were calcined in temperatures between 600 and 1100°C and then leached with hydrochloric acid. Obtained results revealed, in spit of ...
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In this paper, iron removal studies on high iron diasporic bauxite by thermochemical treatment was investigated for the first time. For this purpose, bauxite samples were calcined in temperatures between 600 and 1100°C and then leached with hydrochloric acid. Obtained results revealed, in spit of gradual decrease in both iron and aluminum extraction with rising calcination temperature, iron extraction to aluminum extraction is selective at calcination temperature above 900°C. Leaching studies of calcined sample at 900°C proved that leaching temperature is the most important parameter for iron dissolution in acid and rising leaching temperatures from 20 to 95°C increases iron extraction over 70%. The other optimum parameters are: leaching time120 minutes, acid concentration 50% V/V, grinding size of 210 µm, pulp density of 15% solid by weight. As a result of optimizing parameters, 96.5% of bauxite iron content removed successfully with 88.5% aluminum recovery and solid residue iron content, i.e., the obtained concentrate, decreased from 27.02 to 1.59%.