H Khorrami; B Rezai; A Amini; F Mossavari
Abstract
Mineralogical and liberation studies are the most important parameters used in the selection of separation. An investigation was carried out to identify the various types of minerals present in fluorite ore and to determine the suitability of the methods for its preconcentration and final concentration. ...
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Mineralogical and liberation studies are the most important parameters used in the selection of separation. An investigation was carried out to identify the various types of minerals present in fluorite ore and to determine the suitability of the methods for its preconcentration and final concentration. The sample has been evaluated and characterized by ore microscopy, x-ray diffraction, chemical analysis and also approximate mineralogy based on chemical analysis and Microscopic studies and also the texture characteristics such as grain size, Situation of infor locked particle and their arrangement in the ore body were also investigated. According to surveys conducted this ore contains of fluorite (40.52%), calcite (24%), quartz (20%), smitsonite (8%), galena (2%), clay minerals (3%), barite (1%) and goethite (0.6%). Carbonate phases is two parts sparry calcite, micrite to microsparate piece has been observed. Quartz, in the form of microcrystalline with limonite and goethite oxide of stained has been observed. The liberation degrees of crushed ore in different size fractions was estimated by the Counting method of showed that for fluorite (1000 μm), Calcite (100 μm) and quartz (90 μm) of fluorite in size 100 mesh (150 μm) with quartz (36%) and calcite (23%) were determined. The size fraction of -600, +425, can be assessed for gravity concentration as a preconcentration process and for the size fraction -150,+75 μm for flotation.
B Shahbazi; B Rezai; S.M.J Koleini; M Noaparast
Abstract
In this research the effect of bubble surface area flux on flotation rate constant of coal particles was investigated and the results showed that flotation rate constant increased with increasing bubble surface area flux. The obtained Maximum flotation rate constant was 3.30 /min while the particle size ...
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In this research the effect of bubble surface area flux on flotation rate constant of coal particles was investigated and the results showed that flotation rate constant increased with increasing bubble surface area flux. The obtained Maximum flotation rate constant was 3.30 /min while the particle size and bubble surface area flux were -37mm and 25.891/s, respectively. The bubble-particle collision, attachment and detachment efficiency were calculated in order to analyze the results. The obtained Maximum Stokes collision efficiency was 81.57% while the particle size, bubble surface area flux, and flotation rate constant were -500+420mm, 27.431/s, and 1.17/min, respectively. The obtained Maximum Yoon, Stokes and Potential efficiency were 94.66, 56.74 and 45.61%, respectively. Moreover, the obtained maximum detachment efficiency was 34.57% while the particle size, bubble surface area flux and flotation rate constant were -500+420mm, 16.771/s, and 0.85 /min. The collection efficiency increased with increasing of the bubble surface area flux. The collection efficiency was high for the particle size range of -106+37mm and for out of this particle size range it decreased steadily. So, the low efficiency of floating coarse particles can be attributed to the high efficiency of detachment while the low efficiency of floating of the fine particles was due to the low efficiency of collision.
S. Khoshjavan; B. Rezai; A. Amini
Abstract
In this research, processing of Dalir area phosphate ore was investigated for reduction of its gangue minerals such as carbonates (mainly calcite and poorly dolomite) and silicates minerals. According to characterization studies, phosphate mineral content of the ore was sedimentary collophane mineral ...
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In this research, processing of Dalir area phosphate ore was investigated for reduction of its gangue minerals such as carbonates (mainly calcite and poorly dolomite) and silicates minerals. According to characterization studies, phosphate mineral content of the ore was sedimentary collophane mineral and the predominant constituents of the gangues were calcite and quartz. Liberation degree of phosphate mineral determined by using microscopic and sink and float tests to be 140 µm. Primary flotation tests (un-pre-concentrated) results did not have desirable grade and recovery. So, at first step, phosphates samples was subjected to calcination and scrupping process. After scrupping and removing calcium and magnesium oxide, anionic and cationic flotation tests were done. By using a combination methods (calcining, scrupping and flotation) the grade and recovery of final concentrate reaches to 31% and 62% respectively. Finally a Lab-flowsheet of processing was suggested
S. Khoshjavan; B. Rezai; A. Amini
Abstract
In this research, characterization studies of sedimentary phosphate rock from Zanjan Dalir area with respect to processing are investigated. According to mineralogical studies, phosphate ore (Collophane 28.13%), sedimentary mineral and the predominant constituents of the gangues were Calcite (43.53%), ...
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In this research, characterization studies of sedimentary phosphate rock from Zanjan Dalir area with respect to processing are investigated. According to mineralogical studies, phosphate ore (Collophane 28.13%), sedimentary mineral and the predominant constituents of the gangues were Calcite (43.53%), Quartz and Dolomite (4.65%). Main composition of phosphate rock were P2O5 (11.9% wt), CaO (36.36% wt), SiO2 (24.49% wt) and MgO (1.01% wt). Microscopic studies showed that apatite pletts had inclusions of Calcite and Quartz (about 15-70 microns). Content of inclusions was considerable. Mineralogy texture is very complicated. Liberation degree determined by grain counting (with optic microscope) and sink and float test methods. From The results of liberation degree studies can be inferred that in dimension about 140 microns about 96% of phosphate particles librated. In desliming step about 8.2% of total phosphate was removed. Optimum grinding time to reaching liberation of phosphate particles was obtained about 10 min and 30 second. Organic material determined by heating method (about 1.66% wt). Scanning electron microscopy studies showed that inclusions and organic materials existed. Specific gravity of phosphate particles and gangues difference was low. Based on the mentioned studies, effective method for processing of phosphate minerals from carbonate and silicate impurities is suggested flotation method.
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%.
M. Pakdel; B. Rezai; R. Asgari; K. Nazari
Abstract
Magnetic and electrostatic properties of minerals are the important characterizations used in mineral processing technology for concentration of minerals. Mineralogy and degree of liberation of the ore with a uranium average content of 1540 ppm, has been studied ...
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Magnetic and electrostatic properties of minerals are the important characterizations used in mineral processing technology for concentration of minerals. Mineralogy and degree of liberation of the ore with a uranium average content of 1540 ppm, has been studied by XRD and microscopic methods. Major minerals such as alkali feldspar (Orthoclase), plagioclase (Albite), biotite, chlorite, carbonate and minor minerals such as sphene, zircon, actinolite, tremolite, pitchblende and betafite have been identified in this ore. Additionally, the degree of liberation of orthoclase, albite, biotite and uranium minerals was determined 320, 290, 190 and 110 microns respectively. Based on the results of mineralogy and degree of liberation studies, magnetic and electrostatic tests have been performed on fractions: -420+250, -250+125 and -125+74 microns. High intensity magnetic tests in two ways, wet and dry separations were done by HIMS separator and plate separator. Analyses of magnetic test results showed that the separation has low recovery. Recovery for dry and wet methods was 45.03 and 26.99% respectively. Analyses of electrostatic test results showed that the maximum recovery of these tests is 51.36% uranium and in this state 27.63% uranium in 42.02 weight percent of feed is rejected. Generally, the recovery of these separations was low, so these methods are not suitable for concentration of this ore.
