The comparative beneficiation study of Gyel columbite ore using double stage (magnetic-to-magnetic and magnetic-to-gravity), located in the vicinity of Gyel village in Jos South Local Government Area of Plateau State ...The comparative beneficiation study of Gyel columbite ore using double stage (magnetic-to-magnetic and magnetic-to-gravity), located in the vicinity of Gyel village in Jos South Local Government Area of Plateau State to metallurgical grade was carried out. The ore sample was sourced from 20 different pits each 1.5 × 1.5 × 2 meters deep, 50 meter apart covering a land of 50 hectares. The samples from the 20 pits were crushed, pulverized and homogenized. 200 kg of the homogenized ore sample was used for the experiment and laboratory works. Chemical characterization of the ore sample was carried out using energy dispersive X-ray fluorescence spectrometer (ED-XFR). Single and double stage concentration tests using magnetic and gravity methods were carried out respectively. The results of the chemical analysis of ore sample reveal that, Pit 1 contains 12.26% Nb<sub>2</sub>O<sub>5</sub>, 21.6% Fe<sub>2</sub>O<sub>3</sub>, 36.1% SiO<sub>2</sub>;Pit 20 contains 4.78% Nb<sub>2</sub>O<sub>5</sub>, 19.34% Fe<sub>2</sub>O<sub>3</sub>, 23.96% SiO<sub>2</sub> and the homogenized sample contains 6.71% Nb<sub>2</sub>O<sub>5</sub>, 23.1% Fe<sub>2</sub>O<sub>3</sub> and 27.0% SiO<sub>2</sub> averagely. The liberation study reveals that the niobium of ore can be liberated over a range of sieve size fractions of -355 + 63 μm for the coarse and -63 + 45 μm for the fine particle size fractions. On the basis of this, sieve size fractions of -1400 + 355 μm (as coarse size), -355 + 90 μm (as medium size) and -90 + 45 μm (as fine size) were used for the concentration tests. The concentration test using the double stage processes revealed that the air-floatation followed by rapid magnetic method produced a concentrate with the highest percent assay of 54.48% Nb<sub>2</sub>O<sub>5</sub> with a recovery of 96.53% followed by the rapid-to-rapid magnetic method which produced a concentrate assaying 52.12% Nb<sub>2</sub>O<sub>5</sub> with a recovery of 86.96%. These results meet and surpass the 50% Nb<sub>2</sub>O<sub>5</sub> stipulated as the acceptable metallurgical grade concentrate for niobium metal production in the literature.展开更多
The present work focused on corrosion inhibition of AA6063 type Al-Mg-Si alloy in sodium chloride （NaCI） solution with a silicon carbide inhibitor, using the potentiodynamic electrochemical method. The aluminium all...The present work focused on corrosion inhibition of AA6063 type Al-Mg-Si alloy in sodium chloride （NaCI） solution with a silicon carbide inhibitor, using the potentiodynamic electrochemical method. The aluminium alloy surface morphology was examined, in the as-received and as-corroded in the un-inhibited state, with scanning electron microscopy equipped with energy dispersive spectroscopy （SEM-EDS）. The results obtained via linear polarization indicated a high corrosion potential for the unprotected as-received alloy. Equally, inhibition efficiency as high as 98.82% at 10.0 g/v silicon carbide addition was obtained with increased polarization resistance fRy）, while the current density reduced significantly for inhibited samples compared to the un-inhibited aluminium alloy. The adsorption mechanism of the inhibitor aluminium alloy follows the Langmuir adsorption isotherm. This shows that the corrosion rate of aluminium alloy with silicon carbide in NaCI environment decreased significantly with addition of the inhibitor.展开更多
Determination of the work index of Gyel-Buruku columbite ore sample in Plateau state, Nigeria, was investigated. The sample of the columbite ore was sourced from Gyel village in Jos East Local Government Area of Plate...Determination of the work index of Gyel-Buruku columbite ore sample in Plateau state, Nigeria, was investigated. The sample of the columbite ore was sourced from Gyel village in Jos East Local Government Area of Plateau state, Nigeria. The “reference ores (granites)” samples were sourced from Jiche and Gurum villages of Plateau state respectively. The reference ores and columbite ore of known weights were ground and pulverized. 80% passing size for the columbite ore, Jiche and Gurum granites samples was obtained at 100 μm sieve size for the feeds and products respectively. The work indexes of reference ores i.e. Jiche and Gurum granites were used to calculate the work index of the Gyel columbite ore sample. The values of 3.42 kWh/ton and 2.72 kWh/ton were obtained respectively for the two different reference granites ores samples used and 3.07 kWh/ton was calculated as their average and determined as the value of the work index of the Gyel-Bukuru columbite ore sample. This work index value obtained for the Gyel-Buruku columbite ore sample lies favourably within the work indexes of 3.94 - 10.81 kWh/ton for columbite minerals sighted in the literatures.展开更多
文摘The comparative beneficiation study of Gyel columbite ore using double stage (magnetic-to-magnetic and magnetic-to-gravity), located in the vicinity of Gyel village in Jos South Local Government Area of Plateau State to metallurgical grade was carried out. The ore sample was sourced from 20 different pits each 1.5 × 1.5 × 2 meters deep, 50 meter apart covering a land of 50 hectares. The samples from the 20 pits were crushed, pulverized and homogenized. 200 kg of the homogenized ore sample was used for the experiment and laboratory works. Chemical characterization of the ore sample was carried out using energy dispersive X-ray fluorescence spectrometer (ED-XFR). Single and double stage concentration tests using magnetic and gravity methods were carried out respectively. The results of the chemical analysis of ore sample reveal that, Pit 1 contains 12.26% Nb<sub>2</sub>O<sub>5</sub>, 21.6% Fe<sub>2</sub>O<sub>3</sub>, 36.1% SiO<sub>2</sub>;Pit 20 contains 4.78% Nb<sub>2</sub>O<sub>5</sub>, 19.34% Fe<sub>2</sub>O<sub>3</sub>, 23.96% SiO<sub>2</sub> and the homogenized sample contains 6.71% Nb<sub>2</sub>O<sub>5</sub>, 23.1% Fe<sub>2</sub>O<sub>3</sub> and 27.0% SiO<sub>2</sub> averagely. The liberation study reveals that the niobium of ore can be liberated over a range of sieve size fractions of -355 + 63 μm for the coarse and -63 + 45 μm for the fine particle size fractions. On the basis of this, sieve size fractions of -1400 + 355 μm (as coarse size), -355 + 90 μm (as medium size) and -90 + 45 μm (as fine size) were used for the concentration tests. The concentration test using the double stage processes revealed that the air-floatation followed by rapid magnetic method produced a concentrate with the highest percent assay of 54.48% Nb<sub>2</sub>O<sub>5</sub> with a recovery of 96.53% followed by the rapid-to-rapid magnetic method which produced a concentrate assaying 52.12% Nb<sub>2</sub>O<sub>5</sub> with a recovery of 86.96%. These results meet and surpass the 50% Nb<sub>2</sub>O<sub>5</sub> stipulated as the acceptable metallurgical grade concentrate for niobium metal production in the literature.
基金Supported by the National Research Foundation for the Department of Chemical,Metallurgical and Materials Engineering,Tshwane University of Technology,Pretoria with respect to equipment and funding
文摘The present work focused on corrosion inhibition of AA6063 type Al-Mg-Si alloy in sodium chloride （NaCI） solution with a silicon carbide inhibitor, using the potentiodynamic electrochemical method. The aluminium alloy surface morphology was examined, in the as-received and as-corroded in the un-inhibited state, with scanning electron microscopy equipped with energy dispersive spectroscopy （SEM-EDS）. The results obtained via linear polarization indicated a high corrosion potential for the unprotected as-received alloy. Equally, inhibition efficiency as high as 98.82% at 10.0 g/v silicon carbide addition was obtained with increased polarization resistance fRy）, while the current density reduced significantly for inhibited samples compared to the un-inhibited aluminium alloy. The adsorption mechanism of the inhibitor aluminium alloy follows the Langmuir adsorption isotherm. This shows that the corrosion rate of aluminium alloy with silicon carbide in NaCI environment decreased significantly with addition of the inhibitor.
文摘Determination of the work index of Gyel-Buruku columbite ore sample in Plateau state, Nigeria, was investigated. The sample of the columbite ore was sourced from Gyel village in Jos East Local Government Area of Plateau state, Nigeria. The “reference ores (granites)” samples were sourced from Jiche and Gurum villages of Plateau state respectively. The reference ores and columbite ore of known weights were ground and pulverized. 80% passing size for the columbite ore, Jiche and Gurum granites samples was obtained at 100 μm sieve size for the feeds and products respectively. The work indexes of reference ores i.e. Jiche and Gurum granites were used to calculate the work index of the Gyel columbite ore sample. The values of 3.42 kWh/ton and 2.72 kWh/ton were obtained respectively for the two different reference granites ores samples used and 3.07 kWh/ton was calculated as their average and determined as the value of the work index of the Gyel-Bukuru columbite ore sample. This work index value obtained for the Gyel-Buruku columbite ore sample lies favourably within the work indexes of 3.94 - 10.81 kWh/ton for columbite minerals sighted in the literatures.
