Acid mine drainage (AMD) derives from the oxidation of sulfide minerals, primarily pyrite (FeS2), and is the most severe environmental issue facing the minerals industry. The most common short-term approach to AMD treatment is migration control, such as acid neutralization and metal/metalloid and sulfate removal, through the addition of alkaline materials, including lime (Ca (OH)2), limestone (Ca CO3), gangue minerals and industrial wastes. This requires the continuous input of materials and may result in the production of a vast amount of secondary sludge requiring further treatment and disposal. Addition of chemicals is usually more important in metal/metalloid removal than in sulfate removal unless the sulfate is present in very high concentrations. A more promising long-term strategy for AMD prevention is source control through the complete removal of pyritic minerals and encapsulation of potential risk minerals by coating with impermeable surface layers. This is regarded as the most cost-effective approach, although the mechanisms underpinning this and the implementation procedures are yet to be fully elucidated. It is likely that long- and short-term practices can be combined to optimize the remediation of contaminated mining sites. Some factors such as differing geological and mineralogical characteristics and transportation costs must also be considered for the successful implementation of AMD prevention and remediation strategies. This review also considers some implications for AMD remediation, but the promising bioremediation of AMD is not discussed as it has been extensively reviewed.
{"title":"Acid mine drainage remediation strategies: A review on migration and source controls","authors":"Y. Li, W. Li, Q. Xiao, S. Song, Y. Liu, R. Naidu","doi":"10.19150/MMP.8464","DOIUrl":"https://doi.org/10.19150/MMP.8464","url":null,"abstract":"Acid mine drainage (AMD) derives from the oxidation of sulfide minerals, primarily pyrite (FeS2), and is the most severe environmental issue facing the minerals industry. The most common short-term approach to AMD treatment is migration control, such as acid neutralization and metal/metalloid and sulfate removal, through the addition of alkaline materials, including lime (Ca (OH)2), limestone (Ca CO3), gangue minerals and industrial wastes. This requires the continuous input of materials and may result in the production of a vast amount of secondary sludge requiring further treatment and disposal. Addition of chemicals is usually more important in metal/metalloid removal than in sulfate removal unless the sulfate is present in very high concentrations. A more promising long-term strategy for AMD prevention is source control through the complete removal of pyritic minerals and encapsulation of potential risk minerals by coating with impermeable surface layers. This is regarded as the most cost-effective approach, although the mechanisms underpinning this and the implementation procedures are yet to be fully elucidated. It is likely that long- and short-term practices can be combined to optimize the remediation of contaminated mining sites. Some factors such as differing geological and mineralogical characteristics and transportation costs must also be considered for the successful implementation of AMD prevention and remediation strategies. This review also considers some implications for AMD remediation, but the promising bioremediation of AMD is not discussed as it has been extensively reviewed.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"148-158"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8464","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48362246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Lehtiniemi, T. Kalliomäki, L. Rintala, Petri Latostenmaa, J. Aromaa, O. Forsén, M. Lundström
Conductivity is a typical physico-chemical property that has a substantial effect on electrical energy consumption in the electrorefining process. The objective of this study was to examine the validity of regression models predicting the conductivity of industrial copper electrorefining electrolytes. The models were based on data measured with synthetic solutions on a laboratory scale. The variables included in the models were temperature and the concentrations of copper, nickel, arsenic and sulfuric acid. Both first-order and combined effects of the variables were investigated. The measured data were analyzed using MODDE 8.0 modeling and design software. The validity of the models was investigated by comparing the predicted values with tankhouse conductivity measurements taken at the Boliden Harjavalta Copper Refinery in Pori in Finland. During the tankhouse tests, the conductivity and temperature of the industrial electrolyte were measured, and the composition of the electrolyte was analyzed. The measured conductivity values were compared with the predicted conductivities calculated using the developed models. The conductivity model developed in this paper was shown to be more accurate than previous models and suitable for industrial use.
{"title":"Validation of electrolyte conductivity models in industrial copper electrorefining","authors":"I. Lehtiniemi, T. Kalliomäki, L. Rintala, Petri Latostenmaa, J. Aromaa, O. Forsén, M. Lundström","doi":"10.19150/MMP.8460","DOIUrl":"https://doi.org/10.19150/MMP.8460","url":null,"abstract":"Conductivity is a typical physico-chemical property that has a substantial effect on electrical energy consumption in the electrorefining process. The objective of this study was to examine the validity of regression models predicting the conductivity of industrial copper electrorefining electrolytes. The models were based on data measured with synthetic solutions on a laboratory scale. The variables included in the models were temperature and the concentrations of copper, nickel, arsenic and sulfuric acid. Both first-order and combined effects of the variables were investigated. The measured data were analyzed using MODDE 8.0 modeling and design software. The validity of the models was investigated by comparing the predicted values with tankhouse conductivity measurements taken at the Boliden Harjavalta Copper Refinery in Pori in Finland. During the tankhouse tests, the conductivity and temperature of the industrial electrolyte were measured, and the composition of the electrolyte was analyzed. The measured conductivity values were compared with the predicted conductivities calculated using the developed models. The conductivity model developed in this paper was shown to be more accurate than previous models and suitable for industrial use.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"117-124"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8460","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48320127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The effects of pressure and cake thickness were studied using a split-plot design for pressure filtration of a fine refuse slurry obtained from a bituminous coal preparation facility. Pressure filtration offers the potential to significantly reduce the moisture content of the fine refuse stream with the addition of little to no flocculants, thereby minimizing the volume of refuse stored in impoundments and providing a recycle water stream for use within the plant. Experimental results showed that the final cake moisture decreased with increase in pressure and decrease in cake thickness. In addition, specific cake resistances calculated for the various tests indicated an increasing trend with increasing pressure and decreasing cake thickness. With increase in cake thickness, an increase in cake moisture and the weight of solids deposited in the cake was observed. An ANOVA analysis indicated that both cake thickness and pressure significantly affected the cake moisture, while only cake thickness statistically influenced the weight of solids in the cake. A regression model was developed with an R2 value of about 0.99 to relate cake thickness, the single largest statistically significant factor, with the weight of solids in the cake. Filter capacities were calculated in terms of the solids deposited per unit time based on a product specification of 25 percent cake moisture, and it was observed that the thinnest cake had the highest filter capacity.
{"title":"Effects of cake thickness and pressure on the filtration of coal refuse slurry","authors":"G. Raman, M. Klima","doi":"10.19150/MMP.8461","DOIUrl":"https://doi.org/10.19150/MMP.8461","url":null,"abstract":"The effects of pressure and cake thickness were studied using a split-plot design for pressure filtration of a fine refuse slurry obtained from a bituminous coal preparation facility. Pressure filtration offers the potential to significantly reduce the moisture content of the fine refuse stream with the addition of little to no flocculants, thereby minimizing the volume of refuse stored in impoundments and providing a recycle water stream for use within the plant. Experimental results showed that the final cake moisture decreased with increase in pressure and decrease in cake thickness. In addition, specific cake resistances calculated for the various tests indicated an increasing trend with increasing pressure and decreasing cake thickness. With increase in cake thickness, an increase in cake moisture and the weight of solids deposited in the cake was observed. An ANOVA analysis indicated that both cake thickness and pressure significantly affected the cake moisture, while only cake thickness statistically influenced the weight of solids in the cake. A regression model was developed with an R2 value of about 0.99 to relate cake thickness, the single largest statistically significant factor, with the weight of solids in the cake. Filter capacities were calculated in terms of the solids deposited per unit time based on a product specification of 25 percent cake moisture, and it was observed that the thinnest cake had the highest filter capacity.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"125-132"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8461","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44466788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Z. Mubarok, K. Sukamto, Z. T. Ichlas, A. T. Sugiarto
The use of ozone as an oxidant for the direct leaching of zinc sulfide (sphalerite) concentrate in sulfuric acid medium under atmospheric pressure was explored. The influence of acid concentration, feed gas injection rate, particle size distribution, stirring speed, temperature and slurry density on zinc extraction efficiency was examined. The experimental results showed that the leaching efficiency depends on all of these operating parameters except for stirring speed. It was found that essentially complete dissolution of zinc from the concentrate with the present method can be achieved in only about seven hours under the conditions of sulfuric acid concentration of 2 mol/L, particle size smaller than 74 µm, slurry density of 50 g/L, stirring speed of 420 rpm and feed gas injection rate of 1 L/min at ambient temperature. The experimental results suggest that the dissolution reactions produce independent elemental sulfur that is readily floated and can be easily separated rather than forming a layer on the surface of the reacted particle, as usually observed in a system with ferric-sulfate as oxidizing agent. It was therefore determined that the dissolved ozone play a key role in improving the rate of zinc dissolution from the concentrate. Analysis of the leaching kinetics indicate that the leaching rate follows the shrinking particle model, and the overall dissolution rate of zinc is controlled by a surface reaction.
{"title":"Direct sulfuric acid leaching of zinc sulfide concentrate using ozone as oxidant under atmospheric pressure","authors":"M. Z. Mubarok, K. Sukamto, Z. T. Ichlas, A. T. Sugiarto","doi":"10.19150/MMP.8462","DOIUrl":"https://doi.org/10.19150/MMP.8462","url":null,"abstract":"The use of ozone as an oxidant for the direct leaching of zinc sulfide (sphalerite) concentrate in sulfuric acid medium under atmospheric pressure was explored. The influence of acid concentration, feed gas injection rate, particle size distribution, stirring speed, temperature and slurry density on zinc extraction efficiency was examined. The experimental results showed that the leaching efficiency depends on all of these operating parameters except for stirring speed. It was found that essentially complete dissolution of zinc from the concentrate with the present method can be achieved in only about seven hours under the conditions of sulfuric acid concentration of 2 mol/L, particle size smaller than 74 µm, slurry density of 50 g/L, stirring speed of 420 rpm and feed gas injection rate of 1 L/min at ambient temperature. The experimental results suggest that the dissolution reactions produce independent elemental sulfur that is readily floated and can be easily separated rather than forming a layer on the surface of the reacted particle, as usually observed in a system with ferric-sulfate as oxidizing agent. It was therefore determined that the dissolved ozone play a key role in improving the rate of zinc dissolution from the concentrate. Analysis of the leaching kinetics indicate that the leaching rate follows the shrinking particle model, and the overall dissolution rate of zinc is controlled by a surface reaction.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"133-140"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8462","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45293631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The effect of microwave treatment on the surface roughness and wettability of chalcopyrite (CuFeS2 ) and on the chemical composition of its surface was studied. The microwave source was a conventional multimodal oven with frequency of 2.45 GHz and maximum power of 900 W. Pure chalcopyrite specimens and purified chalcopyrite concentrate were used in this study. Analysis using atomic force microscopy showed a decrease in the surface roughness of the chalcopyrite after microwave radiation. This decrease may be due to oxidation of the surface and formation of iron oxide. Moreover, the surface wettability of the chalcopyrite mineral increased with increasing duration of microwave radiation, which was in good agreement with the micro-flotation mass recovery results. The increased wettability of the surface may be attributed to the decreased surface roughness by microwave radiation. Analysis using scanning electron microscope/energy-dispersive X-ray spectroscopy indicate that after microwave radiation, the contents of sulfur and iron increased whereas that of copper decreased on the surface of the chalcopyrite, significantly changing the average atomic number of the chalcopyrite surface.
{"title":"Effect of microwave treatment on the surface properties of chalcopyrite","authors":"S. M. S. Azghdi, K. Barani","doi":"10.19150/MMP.8463","DOIUrl":"https://doi.org/10.19150/MMP.8463","url":null,"abstract":"The effect of microwave treatment on the surface roughness and wettability of chalcopyrite (CuFeS2 ) and on the chemical composition of its surface was studied. The microwave source was a conventional multimodal oven with frequency of 2.45 GHz and maximum power of 900 W. Pure chalcopyrite specimens and purified chalcopyrite concentrate were used in this study. Analysis using atomic force microscopy showed a decrease in the surface roughness of the chalcopyrite after microwave radiation. This decrease may be due to oxidation of the surface and formation of iron oxide. Moreover, the surface wettability of the chalcopyrite mineral increased with increasing duration of microwave radiation, which was in good agreement with the micro-flotation mass recovery results. The increased wettability of the surface may be attributed to the decreased surface roughness by microwave radiation. Analysis using scanning electron microscope/energy-dispersive X-ray spectroscopy indicate that after microwave radiation, the contents of sulfur and iron increased whereas that of copper decreased on the surface of the chalcopyrite, significantly changing the average atomic number of the chalcopyrite surface.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"141-147"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8463","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41787376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In 2003, a high-temperature pressure leaching circuit to treat copper sulfide concentrates was commissioned at the copper/molybdenum operation at Bagdad, AZ. In late 2007, a medium-temperature pressure leaching circuit was commissioned at the Morenci mine in Arizona. The Morenci circuit was shut down in mid-2008, following a fire in the autoclave circuit. The onset of the global financial crisis in late 2008 resulted in significant changes to the operating profile in the Southwestern United States with respect to concentrates production, concentrates treatment, acid production and acid consumption. As a result of these changes, the Morenci concentrator was shut down, and the pressure leaching circuit remained offline. In late 2014, the increasing acid requirements in the Southwestern United States prompted a reevaluation of the Morenci concentrate leaching facilities. As a result, the pressure leaching circuit was restarted in high-temperature (200 °C) mode in May 2015 and has operated successfully for three years since recommissioning. This paper describes the current pressure leaching circuit configuration and the factors leading to the successful application of copper sulfide concentrate leaching at this location.
{"title":"Pressure leaching of copper concentrates at Morenci, Arizona — 10 years of experience","authors":"C. Green, J. Robertson, J. Marsden","doi":"10.19150/MMP.8459","DOIUrl":"https://doi.org/10.19150/MMP.8459","url":null,"abstract":"In 2003, a high-temperature pressure leaching circuit to treat copper sulfide concentrates was commissioned at the copper/molybdenum operation at Bagdad, AZ. In late 2007, a medium-temperature pressure leaching circuit was commissioned at the Morenci mine in Arizona. The Morenci circuit was shut down in mid-2008, following a fire in the autoclave circuit. The onset of the global financial crisis in late 2008 resulted in significant changes to the operating profile in the Southwestern United States with respect to concentrates production, concentrates treatment, acid production and acid consumption. As a result of these changes, the Morenci concentrator was shut down, and the pressure leaching circuit remained offline. In late 2014, the increasing acid requirements in the Southwestern United States prompted a reevaluation of the Morenci concentrate leaching facilities. As a result, the pressure leaching circuit was restarted in high-temperature (200 °C) mode in May 2015 and has operated successfully for three years since recommissioning. This paper describes the current pressure leaching circuit configuration and the factors leading to the successful application of copper sulfide concentrate leaching at this location.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"109-116"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8459","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41749557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents the results of an analysis and summary of relevant literature on the mechanism of cementation of metals in acidic aqueous media, with the aim of reconsidering the conventional assumptions. The simplicity of the process as a mere galvanic metal displacement is discussed, and the real effects of pH and hydrogen pressure in different cases assessed. Finally, an alternative mechanism scheme with respect to the role of hydrogen species, in agreement with reported data, is proposed.
{"title":"Revisiting the mechanism of cementation: The role of hydrogen species in acidic aqueous media","authors":"J. Casado","doi":"10.19150/MMP.8286","DOIUrl":"https://doi.org/10.19150/MMP.8286","url":null,"abstract":"This paper presents the results of an analysis and summary of relevant literature on the mechanism of cementation of metals in acidic aqueous media, with the aim of reconsidering the conventional assumptions. The simplicity of the process as a mere galvanic metal displacement is discussed, and the real effects of pH and hydrogen pressure in different cases assessed. Finally, an alternative mechanism scheme with respect to the role of hydrogen species, in agreement with reported data, is proposed.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"55-60"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8286","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67758099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The oxide fraction of industrial zinc ash was characterized in terms of chemical and phase composition, leaching behavior in sulfuric acid solutions, and leaching thermal effect. The waste product contained about 68 percent zinc (Zn), 7 percent chlorine (Cl), 2 percent aluminum (Al) and less than 1 percent other metals, such as iron (Fe), manganese (Mn), calcium (Ca) and silicon (Si). It consisted mainly of zinc oxide contaminated with metallic zinc and zinc hydroxide chloride. The dissolution of metals from the zinc ash was determined for solid-to-liquid ratios ranging from 100 to 500 kg/m3, acid concentrations of 10 and 20 percent, and temperatures of 20 and 40 °C. The best result — 130 g/dm3 Zn(II) at 95 percent zinc recovery — was obtained at a solid-to-liquid ratio of 200 kg/m3, sulfuric acid concentration of 20 percent and initial temperature of 40 °C. The final solutions were contaminated mainly by Mn(II) and Fe(III) ions, but the presence of cadmium (Cd(II)) and lead (Pb(II)) ions enabled electrowinning of zinc of about 99 percent purity at high current efficiency of 85 to 99 percent. Leaching of the material was an exothermic process with reaction heat of about 520 kJ/kg.
{"title":"Hydrometallurgical treatment of zinc ash from hot-dip galvanizing process","authors":"E. Rudnik, G. Włoch, L. Szatan","doi":"10.19150/MMP.8288","DOIUrl":"https://doi.org/10.19150/MMP.8288","url":null,"abstract":"The oxide fraction of industrial zinc ash was characterized in terms of chemical and phase composition, leaching behavior in sulfuric acid solutions, and leaching thermal effect. The waste product contained about 68 percent zinc (Zn), 7 percent chlorine (Cl), 2 percent aluminum (Al) and less than 1 percent other metals, such as iron (Fe), manganese (Mn), calcium (Ca) and silicon (Si). It consisted mainly of zinc oxide contaminated with metallic zinc and zinc hydroxide chloride. The dissolution of metals from the zinc ash was determined for solid-to-liquid ratios ranging from 100 to 500 kg/m3, acid concentrations of 10 and 20 percent, and temperatures of 20 and 40 °C. The best result — 130 g/dm3 Zn(II) at 95 percent zinc recovery — was obtained at a solid-to-liquid ratio of 200 kg/m3, sulfuric acid concentration of 20 percent and initial temperature of 40 °C. The final solutions were contaminated mainly by Mn(II) and Fe(III) ions, but the presence of cadmium (Cd(II)) and lead (Pb(II)) ions enabled electrowinning of zinc of about 99 percent purity at high current efficiency of 85 to 99 percent. Leaching of the material was an exothermic process with reaction heat of about 520 kJ/kg.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"69-76"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8288","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43458731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Metallic droplets can remain attached to solid particles within liquid slags, resulting in production losses in several pyrometallurgical industries. This study shows the extension of a recently developed phase field model to include the movement of solid particles in the liquid slag in a system, considering the attachment of liquid metal droplets to solid particles in slags. The influence of this movement on the wetting of the metal droplets to the solid particles in the slag and on the resulting microstructures is investigated as a function of the velocity of the particles. For all wetting regimes, the apparent contact angle in the final microstructures was clearly larger than without particle movement. For the amount of metal attached to the particle, a clear trade-off was found between the speed of motion of the solid particle and the wetting regime.
{"title":"Influence of rigid body motion on the attachment of metallic droplets to solid particles in liquid slags — A phase field study","authors":"I. Bellemans, N. Moelans, K. Verbeken","doi":"10.19150/MMP.8290","DOIUrl":"https://doi.org/10.19150/MMP.8290","url":null,"abstract":"Metallic droplets can remain attached to solid particles within liquid slags, resulting in production losses in several pyrometallurgical industries. This study shows the extension of a recently developed phase field model to include the movement of solid particles in the liquid slag in a system, considering the attachment of liquid metal droplets to solid particles in slags. The influence of this movement on the wetting of the metal droplets to the solid particles in the slag and on the resulting microstructures is investigated as a function of the velocity of the particles. For all wetting regimes, the apparent contact angle in the final microstructures was clearly larger than without particle movement. For the amount of metal attached to the particle, a clear trade-off was found between the speed of motion of the solid particle and the wetting regime.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"87-97"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8290","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42638303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. He, Z. Xie, W. Xie, X. Liu, H. Li, Y. Wu, Y. Hu
China has rich phosphate rock resources, but with their continuous depletion, the rich ore resources have become increasingly scarce, which makes the exploration of collophane more important. Medium- and low-grade phosphate rock cannot be utilized until their impurities have been removed through mineral processing. However, due to the similar physical and chemical properties of dolomite and phosphorus minerals, the separation of dolomite from phosphate rock is a challenge for the beneficiation of phosphate rock.In this study, a collector that can separate dolomite from apatite by selective flotation was combined. The agent, named D12, is a new anionic surfactant that was obtained by the phosphorylation of ether-based nonionic surfactants. In order to determine the performance of the D12 collector, it was used in a flotation test. In this process, the raw ore had phosphorus oxide (P2O5) grade of 22.06 percent and magnesium oxide (MgO) content of 5.94 percent. The grinding fineness of 0.074 mm was approximately 87.33 percent. For roughing, the dosages of sulfuric acid (H2SO4), citric acid and collector were 7 kg/t, 1.5 kg/t and 0.5 kg/t, respectively. In the cleaning stage, the dosages of H2SO4 and collector were 5 kg/t and 0.3 kg/t, respectively. Concentrate grade of 31.02 percent and recovery rate of 68.64 percent with an open circuit were obtained under these conditions. Moreover, concentrate grade of 30.31 percent and recovery rate of 84.47 percent with MgO content of 0.92 percent were obtained with closed-circuit beneficiation indexes. The agent, D12, is promising to be applied to the industrial practice of mineral processing of phosphate rock.
{"title":"Flotation performance of a new collophane reverse flotation collector","authors":"D. He, Z. Xie, W. Xie, X. Liu, H. Li, Y. Wu, Y. Hu","doi":"10.19150/MMP.8291","DOIUrl":"https://doi.org/10.19150/MMP.8291","url":null,"abstract":"China has rich phosphate rock resources, but with their continuous depletion, the rich ore resources have become increasingly scarce, which makes the exploration of collophane more important. Medium- and low-grade phosphate rock cannot be utilized until their impurities have been removed through mineral processing. However, due to the similar physical and chemical properties of dolomite and phosphorus minerals, the separation of dolomite from phosphate rock is a challenge for the beneficiation of phosphate rock.In this study, a collector that can separate dolomite from apatite by selective flotation was combined. The agent, named D12, is a new anionic surfactant that was obtained by the phosphorylation of ether-based nonionic surfactants. In order to determine the performance of the D12 collector, it was used in a flotation test. In this process, the raw ore had phosphorus oxide (P2O5) grade of 22.06 percent and magnesium oxide (MgO) content of 5.94 percent. The grinding fineness of 0.074 mm was approximately 87.33 percent. For roughing, the dosages of sulfuric acid (H2SO4), citric acid and collector were 7 kg/t, 1.5 kg/t and 0.5 kg/t, respectively. In the cleaning stage, the dosages of H2SO4 and collector were 5 kg/t and 0.3 kg/t, respectively. Concentrate grade of 31.02 percent and recovery rate of 68.64 percent with an open circuit were obtained under these conditions. Moreover, concentrate grade of 30.31 percent and recovery rate of 84.47 percent with MgO content of 0.92 percent were obtained with closed-circuit beneficiation indexes. The agent, D12, is promising to be applied to the industrial practice of mineral processing of phosphate rock.","PeriodicalId":18536,"journal":{"name":"Minerals & Metallurgical Processing","volume":"35 1","pages":"98-108"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.19150/MMP.8291","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44414662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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