Dépouillements

Hydrometallurgical process for the separation and recovery of nickel from sulphate heap leach liquor of nickeliferrous laterite ores / S. Agatzini-Leonardou in Minerals engineering, Vol. 22 N° 14 (Novembre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1181–1192 Titre : Hydrometallurgical process for the separation and recovery of nickel from sulphate heap leach liquor of nickeliferrous laterite ores Type de document : texte imprimé Auteurs : S. Agatzini-Leonardou, Auteur ; P.E. Tsakiridis, Auteur ; P. Oustadakis, Auteur Année de publication : 2009 Article en page(s) : pp. 1181–1192 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Laterite  leach  liquor  Hydrometallurgical  process  Nickel  recovery Résumé : The Laboratory of Metallurgy of the National Technical University of Athens has developed and patented a novel integrated hydrometallurgical method, suitable to treat low-grade nickel oxide ores efficiently and economically. It involves heap leaching of the ore by dilute sulphuric acid at ambient temperature, purification of the leach liquor and recovery of nickel and cobalt by electrowinning. A typical composition of the pregnant solution produced from heap leaching is the following: Ni2+ = 5 g/L, Co2+ = 0.3 g/L, Fe3+ = 23.0 g/L, Al3+ = 6.0 g/L, Cr3+ = 1.0 g/L, Mn2+ = 1 g/L and Mg2+ = 8 g/L. The proposed hydrometallurgical process for nickel recovery from real sulphate heap leach liquors consists of the following six (6) unit operations: (1)Removal of iron, aluminium and chromium, as easily filterable crystalline basic sulphate salts of the jarosite–alunite type, at atmospheric pressure, by chemical precipitation at pH: 3.5 and 95 °C. (2)Cobalt, manganese and magnesium extraction over nickel by Cyanex 272 at pH: 5.5, T: 40 °C, with 20% extractant concentration and stripping of the loaded organic phase at T: 40 °C with diluted H2SO4 (4 M). (3)Nickel concentration by solvent extraction using Cyanex 272 at pH: 7.5, T: 40 °C, with 10% extractant concentration and stripping of the loaded organic phase by nickel spent electrolyte (55.45 g/L Ni) at T: 40 °C with diluted H2SO4 (2 M). (4)Nickel electrowinning from sulphate solutions, using stainless steel as cathode and Pb–8%Sb as anode. The pH of the electrolyte (10 g/L H3BO3, 75.95 g/L Ni2+ and 130 g/L Na2SO4) was adjusted at 3.5 and at 60 °C, while the current density was kept constant at 20 mA/cm2. (5)Cobalt and manganese extraction over magnesium by Cyanex 302 at pH: (5.0), T: 40 °C, with 20% extractant concentration and stripping of the loaded organic phase at T: 40 °C with diluted H2SO4 (1 M). (6)Removal of magnesium by chemical precipitation (as brucite), using Ca(OH)2 as neutralizing agent, at atmospheric pressure, pH = 10 and 25 °C. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001514 [article] Hydrometallurgical process for the separation and recovery of nickel from sulphate heap leach liquor of nickeliferrous laterite ores [texte imprimé] / S. Agatzini-Leonardou, Auteur ; P.E. Tsakiridis, Auteur ; P. Oustadakis, Auteur . - 2009 . - pp. 1181–1192. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1181–1192 Mots-clés : Laterite  leach  liquor  Hydrometallurgical  process  Nickel  recovery Résumé : The Laboratory of Metallurgy of the National Technical University of Athens has developed and patented a novel integrated hydrometallurgical method, suitable to treat low-grade nickel oxide ores efficiently and economically. It involves heap leaching of the ore by dilute sulphuric acid at ambient temperature, purification of the leach liquor and recovery of nickel and cobalt by electrowinning. A typical composition of the pregnant solution produced from heap leaching is the following: Ni2+ = 5 g/L, Co2+ = 0.3 g/L, Fe3+ = 23.0 g/L, Al3+ = 6.0 g/L, Cr3+ = 1.0 g/L, Mn2+ = 1 g/L and Mg2+ = 8 g/L. The proposed hydrometallurgical process for nickel recovery from real sulphate heap leach liquors consists of the following six (6) unit operations: (1)Removal of iron, aluminium and chromium, as easily filterable crystalline basic sulphate salts of the jarosite–alunite type, at atmospheric pressure, by chemical precipitation at pH: 3.5 and 95 °C. (2)Cobalt, manganese and magnesium extraction over nickel by Cyanex 272 at pH: 5.5, T: 40 °C, with 20% extractant concentration and stripping of the loaded organic phase at T: 40 °C with diluted H2SO4 (4 M). (3)Nickel concentration by solvent extraction using Cyanex 272 at pH: 7.5, T: 40 °C, with 10% extractant concentration and stripping of the loaded organic phase by nickel spent electrolyte (55.45 g/L Ni) at T: 40 °C with diluted H2SO4 (2 M). (4)Nickel electrowinning from sulphate solutions, using stainless steel as cathode and Pb–8%Sb as anode. The pH of the electrolyte (10 g/L H3BO3, 75.95 g/L Ni2+ and 130 g/L Na2SO4) was adjusted at 3.5 and at 60 °C, while the current density was kept constant at 20 mA/cm2. (5)Cobalt and manganese extraction over magnesium by Cyanex 302 at pH: (5.0), T: 40 °C, with 20% extractant concentration and stripping of the loaded organic phase at T: 40 °C with diluted H2SO4 (1 M). (6)Removal of magnesium by chemical precipitation (as brucite), using Ca(OH)2 as neutralizing agent, at atmospheric pressure, pH = 10 and 25 °C. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001514

Evaluation of models for air recovery in a laboratory flotation column / R.H. Estrada-Ruiz in Minerals engineering, Vol. 22 N° 14 (Novembre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1193–1199 Titre : Evaluation of models for air recovery in a laboratory flotation column Type de document : texte imprimé Auteurs : R.H. Estrada-Ruiz, Auteur ; R. Pérez-Garibay, Auteur Année de publication : 2009 Article en page(s) : pp. 1193–1199 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Column  flotation  Flotation  froths  Flotation  bubbles  Froth  flotation Résumé : One of the more interesting recent topics in flotation modelling is the association between the fraction of air that overflows to the concentrate as unbroken bubbles (air recovery, α) and concentrate recovery. This paper analyses several models to estimate air recovery. These models were tested using experimental data obtained with a laboratory flotation column (2 m high; 0.095 m diam.), which was used to float sphalerite. Predictions from these models were compared with the results obtained by image analysis. The aim of this last technique was to have a reference measurement, quantifying by visual detection (manual method) the bubbles bursting on the surface. Based on the experimental results, the best models were identified. This kind of comparison is valuable for simulator developers. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001526 [article] Evaluation of models for air recovery in a laboratory flotation column [texte imprimé] / R.H. Estrada-Ruiz, Auteur ; R. Pérez-Garibay, Auteur . - 2009 . - pp. 1193–1199. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1193–1199 Mots-clés : Column  flotation  Flotation  froths  Flotation  bubbles  Froth  flotation Résumé : One of the more interesting recent topics in flotation modelling is the association between the fraction of air that overflows to the concentrate as unbroken bubbles (air recovery, α) and concentrate recovery. This paper analyses several models to estimate air recovery. These models were tested using experimental data obtained with a laboratory flotation column (2 m high; 0.095 m diam.), which was used to float sphalerite. Predictions from these models were compared with the results obtained by image analysis. The aim of this last technique was to have a reference measurement, quantifying by visual detection (manual method) the bubbles bursting on the surface. Based on the experimental results, the best models were identified. This kind of comparison is valuable for simulator developers. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001526

Investigation on measuring the fill level of an industrial ball mill based on the vibration characteristics of the mill shell / Peng Huang in Minerals engineering, Vol. 22 N° 14 (Novembre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1200–1208 Titre : Investigation on measuring the fill level of an industrial ball mill based on the vibration characteristics of the mill shell Type de document : texte imprimé Auteurs : Peng Huang, Auteur ; Min-ping Jia, Auteur ; Bing-lin Zhong, Auteur Année de publication : 2009 Article en page(s) : pp. 1200–1208 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Ball  mill  Fill  level  Vibration  signal  Coal Résumé : A novel characteristic variable of fill level has been proposed, in order to reduce the influence of various factors on measuring the fill level and improve the measurement accuracy of the fill level. A relationship was developed between the fill level and the angular position of the maximum vibration point on the mill shell through theoretical calculation and on-site experiments. This relationship was studied theoretically with two assumptions. The vibration signals were then collected by an accelerometer mounted directly on the mill shell, and analyzed on the time domain to obtain the maximum vibration point on the mill shell, in order to study the correlation between the fill level and this angular position. Both the results of theoretical calculations and experiments show that the position of the maximum vibration point on the mill shell moves to a lower angular position as the fill level increases. Comparison of the traditional and the new characteristic variable of the fill level reveals that the characteristic variable proposed in this paper is more superior and stable. It shows potential for measuring the fill level more accurately. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001538 [article] Investigation on measuring the fill level of an industrial ball mill based on the vibration characteristics of the mill shell [texte imprimé] / Peng Huang, Auteur ; Min-ping Jia, Auteur ; Bing-lin Zhong, Auteur . - 2009 . - pp. 1200–1208. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1200–1208 Mots-clés : Ball  mill  Fill  level  Vibration  signal  Coal Résumé : A novel characteristic variable of fill level has been proposed, in order to reduce the influence of various factors on measuring the fill level and improve the measurement accuracy of the fill level. A relationship was developed between the fill level and the angular position of the maximum vibration point on the mill shell through theoretical calculation and on-site experiments. This relationship was studied theoretically with two assumptions. The vibration signals were then collected by an accelerometer mounted directly on the mill shell, and analyzed on the time domain to obtain the maximum vibration point on the mill shell, in order to study the correlation between the fill level and this angular position. Both the results of theoretical calculations and experiments show that the position of the maximum vibration point on the mill shell moves to a lower angular position as the fill level increases. Comparison of the traditional and the new characteristic variable of the fill level reveals that the characteristic variable proposed in this paper is more superior and stable. It shows potential for measuring the fill level more accurately. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001538

Effect of ultrasound on separation selectivity and efficiency of flotation / Emin Cafer Cilek in Minerals engineering, Vol. 22 N° 14 (Novembre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1209–1217 Titre : Effect of ultrasound on separation selectivity and efficiency of flotation Type de document : texte imprimé Auteurs : Emin Cafer Cilek, Auteur ; Selcuk Ozgen, Auteur Année de publication : 2009 Article en page(s) : pp. 1209–1217 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Flotation  froths  Flotation  kinetics  Sulphide  ores Résumé : The effect of the use of ultrasound in the froth phase on the flotation performance has been investigated in relation to the flotation rate of a complex sulphide ore. A series of kinetic flotation tests with and without ultrasound were conducted in a flotation machine with a 2-L cell, in which an ultrasonic probe is located in the froth zone. The results indicate that there is a considerable effect of ultrasound on separation selectivity and efficiency in the flotation of a complex sulphide ore at intermediate and high level airflow rates whereas, no significant differences in the separation performance were obtained from the flotation with and without ultrasound at low airflow rates. In addition, the results of the size-by-size analysis show that a much better cleaning action in the froth was promoted for coarse particles rather than fine particles as a result of the use of ultrasound. As a result of increase in the bubble coalescence, it was found that the use of ultrasound in the froth is more effective at shallow froths. Therefore, either effective pulp volume can be increased with a negligible loss of flotation performance or the pulp density can be decreased to obtain better product quality with the use of ultrasound in shallow froths. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S089268750900154X [article] Effect of ultrasound on separation selectivity and efficiency of flotation [texte imprimé] / Emin Cafer Cilek, Auteur ; Selcuk Ozgen, Auteur . - 2009 . - pp. 1209–1217. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1209–1217 Mots-clés : Flotation  froths  Flotation  kinetics  Sulphide  ores Résumé : The effect of the use of ultrasound in the froth phase on the flotation performance has been investigated in relation to the flotation rate of a complex sulphide ore. A series of kinetic flotation tests with and without ultrasound were conducted in a flotation machine with a 2-L cell, in which an ultrasonic probe is located in the froth zone. The results indicate that there is a considerable effect of ultrasound on separation selectivity and efficiency in the flotation of a complex sulphide ore at intermediate and high level airflow rates whereas, no significant differences in the separation performance were obtained from the flotation with and without ultrasound at low airflow rates. In addition, the results of the size-by-size analysis show that a much better cleaning action in the froth was promoted for coarse particles rather than fine particles as a result of the use of ultrasound. As a result of increase in the bubble coalescence, it was found that the use of ultrasound in the froth is more effective at shallow froths. Therefore, either effective pulp volume can be increased with a negligible loss of flotation performance or the pulp density can be decreased to obtain better product quality with the use of ultrasound in shallow froths. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S089268750900154X

Separation performance of double deck banana screens / Paul W. Cleary in Minerals engineering, Vol. 22 N° 14 (Novembre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1218–1229 Titre : Separation performance of double deck banana screens : Part 1: Flow and separation for different accelerations Type de document : texte imprimé Auteurs : Paul W. Cleary, Auteur ; Matthew D. Sinnott, Auteur ; Rob D. Morrison, Auteur Année de publication : 2009 Article en page(s) : pp. 1218–1229 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Screening  Separation  Discrete  element  method  DEM  Banana  screen Résumé : Banana screens are often used for high capacity separation of iron ore, coal and aggregates into different size fractions. They consist of one or more curved decks that are fitted with screen panels with arrays of square or rectangular holes. The screen structure is vibrated at high frequency to generate peak accelerations of around 4–6g which separates particles flowing over each screen according to their size. Screens are often used to close comminution circuits and return specific size fractions of rock to different destinations such as pebble mills, crushers and back into the mills. All multi-deck screens are difficult to sample for intermediate products which makes measurement and optimization very difficult. Banana screens are even more difficult because the screen cut size varies with the varying slope of the decks. In this paper, the discrete element method (DEM) is used to simulate a full industrial scale double deck banana screen for a range of accelerations. The nature of the particle flow through this complex machine is explored for a range of peak accelerations. Critical aspects of the flow are linked to the separation performance. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001551 [article] Separation performance of double deck banana screens : Part 1: Flow and separation for different accelerations [texte imprimé] / Paul W. Cleary, Auteur ; Matthew D. Sinnott, Auteur ; Rob D. Morrison, Auteur . - 2009 . - pp. 1218–1229. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1218–1229 Mots-clés : Screening  Separation  Discrete  element  method  DEM  Banana  screen Résumé : Banana screens are often used for high capacity separation of iron ore, coal and aggregates into different size fractions. They consist of one or more curved decks that are fitted with screen panels with arrays of square or rectangular holes. The screen structure is vibrated at high frequency to generate peak accelerations of around 4–6g which separates particles flowing over each screen according to their size. Screens are often used to close comminution circuits and return specific size fractions of rock to different destinations such as pebble mills, crushers and back into the mills. All multi-deck screens are difficult to sample for intermediate products which makes measurement and optimization very difficult. Banana screens are even more difficult because the screen cut size varies with the varying slope of the decks. In this paper, the discrete element method (DEM) is used to simulate a full industrial scale double deck banana screen for a range of accelerations. The nature of the particle flow through this complex machine is explored for a range of peak accelerations. Critical aspects of the flow are linked to the separation performance. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001551

Separation performance of double deck banana screens / Paul W. Cleary in Minerals engineering, Vol. 22 N° 14 (Novembre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1230–1244 Titre : Separation performance of double deck banana screens Titre original : Part 2: Quantitative predictions Type de document : texte imprimé Auteurs : Paul W. Cleary, Auteur ; Matthew D. Sinnott, Auteur ; Rob D. Morrison, Auteur Année de publication : 2009 Article en page(s) : pp. 1230–1244 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Screening  Separation  Discrete  element  method  DEM  Banana  screen Résumé : Banana screens are often used for high capacity separation of iron ore, coal and aggregates into different size fractions. They consist of one or more curved decks that are fitted with screen panels with arrays of square or rectangular holes. The screen structure is vibrated while a dense stream of particles flows over it and is separated according to size. The material discharging from the top of the deck is the oversize and may become a coarse product or be crushed and recycled to the screen feed. The material falling through the deck can be further separated by additional decks below. Each lower deck returns a product stream and the material passing out through the bottom deck is the undersize. In this paper, Discrete Element Method (DEM) is used to explore the separation performance of a full industrial scale double deck banana screen for a peak acceleration of 5g. The separation efficiency of each deck is analysed and the individual contributions of each screen panel are assessed using outputs from the model. Residence time distributions for particles on each deck provide insight into both the transport characteristics along the deck and the separation performance through each deck. The top and bottom decks have very different flow behaviour with very different bed structure and motion. The stresses applied by the flowing particles to the screen cloths and the impact and abrasive wear on the screen surfaces are evaluated. Finally, the energy absorbed by particles provides insight into the extent of particle degradation produced by transiting the screen. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001563 [article] Separation performance of double deck banana screens = Part 2: Quantitative predictions [texte imprimé] / Paul W. Cleary, Auteur ; Matthew D. Sinnott, Auteur ; Rob D. Morrison, Auteur . - 2009 . - pp. 1230–1244. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1230–1244 Mots-clés : Screening  Separation  Discrete  element  method  DEM  Banana  screen Résumé : Banana screens are often used for high capacity separation of iron ore, coal and aggregates into different size fractions. They consist of one or more curved decks that are fitted with screen panels with arrays of square or rectangular holes. The screen structure is vibrated while a dense stream of particles flows over it and is separated according to size. The material discharging from the top of the deck is the oversize and may become a coarse product or be crushed and recycled to the screen feed. The material falling through the deck can be further separated by additional decks below. Each lower deck returns a product stream and the material passing out through the bottom deck is the undersize. In this paper, Discrete Element Method (DEM) is used to explore the separation performance of a full industrial scale double deck banana screen for a peak acceleration of 5g. The separation efficiency of each deck is analysed and the individual contributions of each screen panel are assessed using outputs from the model. Residence time distributions for particles on each deck provide insight into both the transport characteristics along the deck and the separation performance through each deck. The top and bottom decks have very different flow behaviour with very different bed structure and motion. The stresses applied by the flowing particles to the screen cloths and the impact and abrasive wear on the screen surfaces are evaluated. Finally, the energy absorbed by particles provides insight into the extent of particle degradation produced by transiting the screen. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001563

The use of diffuse reflectance spectroscopy for the characterization of iron ores / Geraldo Magela Da Costa in Minerals engineering, Vol. 22 N° 14 (Novembre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1245–1250 Titre : The use of diffuse reflectance spectroscopy for the characterization of iron ores Type de document : texte imprimé Auteurs : Geraldo Magela Da Costa, Auteur ; Vidal Barrón, Auteur ; César Mendonça Ferreira, Auteur Année de publication : 2009 Article en page(s) : pp. 1245–1250 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Iron  ores  Goethite  Martite  Specularite  Reflectance Résumé : The aim of this work was to develop a diffuse reflectance methodology for quantifying minerals in powdered iron ores, which is a key quality control requirement for these materials. Selected samples ranging widely in their concentrations of hematite (as specularite and martite), goethite, magnetite, and quartz were collected in mines from the Iron Quadrangle, Minas Gerais State, and also in the Carajás region, Pará State, Brazil. A chemometric analysis based on the concentrations of the different minerals as determined with a combination of conventional methods (chemical analysis, X-ray diffraction, Mössbauer spectroscopy, light-reflected microscopy, and magnetic susceptibility) and the principal components derived from the diffuse reflectance spectra in the visible range was performed. Principal component regression analysis provided successful calibration for the concentrations of goethite (r2 = 0.94; standard error of validation (SEv) = 4.2%) and hematite (r2 = 0.89; SEv = 7.4%), in addition to good estimates for quartz (r2 = 0.83; SEv = 7.4%), specularite (r2 = 0.80; SEv = 11.6%), and martite (r2 = 0.78; SEv = 10.6%). Our results suggest that diffuse reflectance spectroscopy is a promising tool for the simultaneous determination of minerals in iron ores within a few minutes only. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001587 [article] The use of diffuse reflectance spectroscopy for the characterization of iron ores [texte imprimé] / Geraldo Magela Da Costa, Auteur ; Vidal Barrón, Auteur ; César Mendonça Ferreira, Auteur . - 2009 . - pp. 1245–1250. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1245–1250 Mots-clés : Iron  ores  Goethite  Martite  Specularite  Reflectance Résumé : The aim of this work was to develop a diffuse reflectance methodology for quantifying minerals in powdered iron ores, which is a key quality control requirement for these materials. Selected samples ranging widely in their concentrations of hematite (as specularite and martite), goethite, magnetite, and quartz were collected in mines from the Iron Quadrangle, Minas Gerais State, and also in the Carajás region, Pará State, Brazil. A chemometric analysis based on the concentrations of the different minerals as determined with a combination of conventional methods (chemical analysis, X-ray diffraction, Mössbauer spectroscopy, light-reflected microscopy, and magnetic susceptibility) and the principal components derived from the diffuse reflectance spectra in the visible range was performed. Principal component regression analysis provided successful calibration for the concentrations of goethite (r2 = 0.94; standard error of validation (SEv) = 4.2%) and hematite (r2 = 0.89; SEv = 7.4%), in addition to good estimates for quartz (r2 = 0.83; SEv = 7.4%), specularite (r2 = 0.80; SEv = 11.6%), and martite (r2 = 0.78; SEv = 10.6%). Our results suggest that diffuse reflectance spectroscopy is a promising tool for the simultaneous determination of minerals in iron ores within a few minutes only. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001587

Simulating particle agglomeration in the flash smelting reaction shaft / D.R. Higgins in Minerals engineering, Vol. 22 N° 14 (Novembre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1251–1265 Titre : Simulating particle agglomeration in the flash smelting reaction shaft Type de document : texte imprimé Auteurs : D.R. Higgins, Auteur ; N.B. Gray, Auteur ; M.R. Davidson, Auteur Année de publication : 2009 Article en page(s) : pp. 1251–1265 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Agglomeration  Flue  dusts  Pyrometallurgy  Computational  fluid  dynamics  Modelling Résumé : A steady-state, axi-symmetric, numerical model was developed to investigate the agglomeration of molten particles of sulphide ore in the reaction shaft of a flash smelting process used for extracting copper. The turbulent, particle-laden, gas flow was simulated in conjunction with a population balance model to account for agglomeration. The agglomeration was found to depend primarily on the particle to gas mass loading ratio, and the particle size and turbulence intensity at the shaft inlet. Predictions compared well with the limited experimental data in the literature. Increasing the angle at which the flow enters the shaft from the burner was found to increase agglomeration up to a critical angle at which the flow behaviour changes. The results have implications for the control and reduction of dust levels in the waste gas stream. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001599 [article] Simulating particle agglomeration in the flash smelting reaction shaft [texte imprimé] / D.R. Higgins, Auteur ; N.B. Gray, Auteur ; M.R. Davidson, Auteur . - 2009 . - pp. 1251–1265. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1251–1265 Mots-clés : Agglomeration  Flue  dusts  Pyrometallurgy  Computational  fluid  dynamics  Modelling Résumé : A steady-state, axi-symmetric, numerical model was developed to investigate the agglomeration of molten particles of sulphide ore in the reaction shaft of a flash smelting process used for extracting copper. The turbulent, particle-laden, gas flow was simulated in conjunction with a population balance model to account for agglomeration. The agglomeration was found to depend primarily on the particle to gas mass loading ratio, and the particle size and turbulence intensity at the shaft inlet. Predictions compared well with the limited experimental data in the literature. Increasing the angle at which the flow enters the shaft from the burner was found to increase agglomeration up to a critical angle at which the flow behaviour changes. The results have implications for the control and reduction of dust levels in the waste gas stream. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001599

Electrowinning of zinc from sulphate solutions in the presence of perfluoroglutaric acid / C.K. Sarangi in Minerals engineering, Vol. 22 N° 14 (Novembre 2009) 

Public ISBD [article]  in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1266–1269 Titre : Electrowinning of zinc from sulphate solutions in the presence of perfluoroglutaric acid Type de document : texte imprimé Auteurs : C.K. Sarangi, Auteur ; B.C. Tripathy, Auteur ; I. N. Bhattacharya, Auteur Année de publication : 2009 Article en page(s) : pp. 1266–1269 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Antimony(III)  Current  efficiency  Electrowinning  Morphology  Perfluoroglutaric  acid  Zinc Résumé : This paper deals with the effect of perfluoroglutaric acid in the presence and absence of antimony(III) on the cathodic current efficiency, energy consumption and polarisation behaviour of the cathode during electrowinning of zinc from acidic sulphate solutions. Surface morphologies and crystallographic orientations of the zinc deposits were also examined using scanning electron microscopy and X-ray diffraction analysis. Perfluoroglutaric acid was found to increase the current efficiency, decrease the energy consumption and produce better surface morphologies. Voltammetric studies revealed that perfluoroglutaric acid when present in the solution depolarised the cathode which was also reflected in the deposit morphologies showing bigger size crystal planes than the deposit obtained in its absence. Presence of antimony(III) in the solution deteriorated the deposit quality and resulted in corrugated deposits at higher concentrations. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001575 [article] Electrowinning of zinc from sulphate solutions in the presence of perfluoroglutaric acid [texte imprimé] / C.K. Sarangi, Auteur ; B.C. Tripathy, Auteur ; I. N. Bhattacharya, Auteur . - 2009 . - pp. 1266–1269. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 22 N° 14 (Novembre 2009) . - pp. 1266–1269 Mots-clés : Antimony(III)  Current  efficiency  Electrowinning  Morphology  Perfluoroglutaric  acid  Zinc Résumé : This paper deals with the effect of perfluoroglutaric acid in the presence and absence of antimony(III) on the cathodic current efficiency, energy consumption and polarisation behaviour of the cathode during electrowinning of zinc from acidic sulphate solutions. Surface morphologies and crystallographic orientations of the zinc deposits were also examined using scanning electron microscopy and X-ray diffraction analysis. Perfluoroglutaric acid was found to increase the current efficiency, decrease the energy consumption and produce better surface morphologies. Voltammetric studies revealed that perfluoroglutaric acid when present in the solution depolarised the cathode which was also reflected in the deposit morphologies showing bigger size crystal planes than the deposit obtained in its absence. Presence of antimony(III) in the solution deteriorated the deposit quality and resulted in corrugated deposits at higher concentrations. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687509001575

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