Microtextures and struetures of 9 hydrothermal chimneys sampled on the small spreading ridge Of the Mari ana Trough during SONNE Cruise 57 (SO57) and 69 (SO69) in 1988 and 1990 were studied by means of scanning elec...Microtextures and struetures of 9 hydrothermal chimneys sampled on the small spreading ridge Of the Mari ana Trough during SONNE Cruise 57 (SO57) and 69 (SO69) in 1988 and 1990 were studied by means of scanning electron microscope. The results reveal that the two types of chimneys from the Mariana Trough. the 'silicic chimneys' containing Fe sulfide and the pure 'silica chimneys' without sulfide, vary distinctly not only in mineral and chemical compositions, but also in microtextures and structures. The silicic chimneys generally show three major types of microtextures.The inside of the chimneys is dominated by holocrystalline or semicrystalline idiomorphic and hypidiomorphic granular textures and the outwall by amorphous colloidal texture. In some of the silicic chimneys relict texture is observed. However,the pure silica chimneys show chiefly amorphous colloidal texture from the inside to the outwall. Microstructurally. theinside of the silicic chimneys is dominated by a 'silica-covering' structure and a 'voidfilling' structure, and the outwall by a chain-like or three-dimentional chain-network structure built up by individual opal globules, whereas the pure silica chimneys are mainly three-dimentional chain-network and the dense silica bands in structure. These variations suggest that not only mineralizing conditions but also processes differ distinctly during the formation of the two types of chimneys, and that hydrothermal mineralization in the Mariana Trough shows a multistage or multieplsodical nature.展开更多
White sandstone samples from Hanout area of Late Cambrian-Early Ordovician sandstone in south of Jordan were studied and assessed as a source of glass sand. Upgrading the sand included removing or reducing the content...White sandstone samples from Hanout area of Late Cambrian-Early Ordovician sandstone in south of Jordan were studied and assessed as a source of glass sand. Upgrading the sand included removing or reducing the content of the contaminant oxides and the heavy minerals. The aim of this research was to achieve this upgrading by examining the best-suited and cost-effective processing method(s) with sufficient product recovery. Following the initial sample characterisation at “bench scale”, a pilot study was performed. A high-grade Glass Sand product of 500 - 125 μm size fraction was produced by wet screening, attrition scrubbing and the separation of heavy minerals using spirals. The high quality Glass Sand product compared well with Grade-A of the British Standard for glass sand. Due to the relatively low level of impurities in the raw material, a substantial silica sand recovery was produced with a high silica grade. The silica sand product was capable to be used in the high quality glass industry and in many other applications where pure silica is required. The mass flowrate of the feeds and the products in the spiral was calculated for the bulk sample as well as the amount of water required operating the process.展开更多
In order to gain practical experience and hands-on skills,full-time professional master degree postgraduate in mineral processing engineering should engage in professional practices.Nonetheless,a series of problems,in...In order to gain practical experience and hands-on skills,full-time professional master degree postgraduate in mineral processing engineering should engage in professional practices.Nonetheless,a series of problems,including insufficient time for practice,low management level,inadequate implementation of the double-supervisor system,and poor results of professional practice,has reduced the effectiveness of professional practice.In view of the aforementioned problems and the characteristics of the discipline,this paper proposes several strategies for improving the effectiveness of professional practice for postgraduates in mineral processing engineering.展开更多
A better understanding of solid-liquid separation would assist in improving the thickening performance and perhaps water recovery as well. The present work aimed to develop an empirical model to study the effects of o...A better understanding of solid-liquid separation would assist in improving the thickening performance and perhaps water recovery as well. The present work aimed to develop an empirical model to study the effects of ore properties on the thickening process based on pilot tests using a column. A hydro-cyclone was used to prepare the required samples for the experiments. The model significantly predicted the experimental underflow solid content using a regression equation at a given solid flux and bed level for different samples, indicating that ore properties are the effective parameters in the thickening process. This work confirned that the water recovery would be increased about 5% by separating the feed into two parts, overflow and underflow, and introducing two different thickeners into them separately. This is duo to the fact that thickeners are limited by permeability and compressibility in operating conditions.展开更多
The latest progress in mineral processing in China is described. It is also pointed out that the existing technology can not meet the needs of economic development. The combined challenges of poor resources, economica...The latest progress in mineral processing in China is described. It is also pointed out that the existing technology can not meet the needs of economic development. The combined challenges of poor resources, economical benefits and environmental pollution issues require further research to upgrade the separation efficiency economically. The methods of mineral processing should play a more important part in waste treatment such as wastewater treatment, the remediation of contaminated soil and the recycling of wastes. Biomineral technology will be utilised in the near future.展开更多
Rare metal ore reserves are an important strategic resource, and their metallogenic mechanism and mineralization studies have also been received widespread international attention.
Spinel exsolution is widespread in titanomagnetite from the Fe-Ti oxide gabbro of the Panzhihua intrusion, Emeishan Large Igneous Province, SW China. However, little research has been conducted into the implications o...Spinel exsolution is widespread in titanomagnetite from the Fe-Ti oxide gabbro of the Panzhihua intrusion, Emeishan Large Igneous Province, SW China. However, little research has been conducted into the implications of patterns in the mineralogical characteristics of the spinel for spatial variation in the controls on the exsolution mechanism and, hence, the formation process of the ore deposit. This study selected the Lanjiahuoshan Ore Block in the Panzhihua V-Ti magnetite deposit to explore this issue, systematically studying exsolution textures in the titanomagnetite through petrographic observation and the integrated use of in-situ microanalysis. The results show that the exsolved spinel gradually becomes finer-grained and less abundant from the center to edge and the bottom to top of the ore bodies. Compositionally, there is an inverse correlation between the size of exsolved spinel grains and their Mg# value. In addition, there is compositional zonation in the spinel interiors, with a gradual increase in the Mg content and decrease in Fe content from the core to the rim. The analysis suggests that fractional crystallization of ferrotitanium magma with a high oxygen fugacity in a shallow magma chamber caused compositional differences in the primary magnetite solid solution in different parts of the Panzhihua intrusion. Additionally, the thermal evolution of the magnetite solid solution differed in different parts of orebody, bringing about variations in spinel development. Together, these effects resulted in spatial variation in the abundance, grain size, and morphology of spinel in different parts of the orebody and intrusion that follows an identifiable distribution law. Furthermore, the compositional zonation of exsolved spinels reflects the rapid growth of exsolution features in a high-temperature environment. Thus, the size, morphology, abundance, and composition of spinel exsolution features in titanomagnetite provide a valuable petrogenetic tool for estimating the maturity and formational environment of the deposit.展开更多
The first International Conference on Modern Process Mineralogy and Mineral Processing, organized by the Nonferrous Metals Society of China and hosted by Beijing General Research Institute of Mining and Metallurgy,was...The first International Conference on Modern Process Mineralogy and Mineral Processing, organized by the Nonferrous Metals Society of China and hosted by Beijing General Research Institute of Mining and Metallurgy,was held on September 22-25,1992,in Beijing,China.About 350 scholars and experts from 25 countries and regions showed up at the conference and 130 papers were presented,among them 98 papers are of mineral processing.Some of the papers given in mineral processing are summed up as follows.展开更多
The effects of various general and heavy metal ions in acidic cadmium-containing wastewater on SBR desulfurization and cadmium removal under different concentrations were studied.CrO_(4)^(2-) and S^(2-) inhibited SRB ...The effects of various general and heavy metal ions in acidic cadmium-containing wastewater on SBR desulfurization and cadmium removal under different concentrations were studied.CrO_(4)^(2-) and S^(2-) inhibited SRB mineralization,and Mg^(2+),Ca^(2+),Fe^(2+),and Fe^(3+) promoted SRB mineralization at low concentration(<50 mg/L).The inhibitory concentrations of Cu^(2+),Mn^(2+),Co^(2+),Zn^(2+),Pb^(2+),Hg^(2+),Cr^(3+),and Ni^(2+) were 10,30,2,20,25,5,30 mg/L,respectively.The inhibition order was Co^(2+)>Hg^(2+)>Cu^(2+)>Ni^(2+)>Zn^(2+)>Pb^(2+)>Mn^(2+)>Cr^(3+).Furthermore,the inverted microscopy and scanning electron microscopy(SEM)were used to observe the sediment crystallization process from macroscopic and microscopic viewpoints in the optimized ion environment.The experimental results show that under the mineralization of SRB,cadmium sediment crystallization is mainly divided into the rapid growth of bacteria,crystal nucleus production,block formation,and crystallization occuration.At the same time,X-ray diffraction(XRD)and energy-dispersive spectra(EDS)have also confirmed the sediment and crystallization.展开更多
1 Introduction Studies of marine sedimentary phosphate rock have lasted decades,scholars proposed some standpoints about mineralization,however,the genesis of mineral deposits remains to be a controversial question(Sh...1 Introduction Studies of marine sedimentary phosphate rock have lasted decades,scholars proposed some standpoints about mineralization,however,the genesis of mineral deposits remains to be a controversial question(She et al.,2013).There are many viewpoints of mineralization about the Doushantuo phosphorites,Central Guizhou,including biological mineralization(Mi et al.,2010;Shi et al.,2005),展开更多
Social economic growth and the increasing demand for mineral resources have promoted the development of metallic mineral processing technology.Therefore,in order to satisfy the demands for development in mining,cultiv...Social economic growth and the increasing demand for mineral resources have promoted the development of metallic mineral processing technology.Therefore,in order to satisfy the demands for development in mining,cultivating comprehensive mineral processing engineering professionals with strong innovative practical skills has become the top priority in current education.We have established a new course,“Metallic Mineral Processing,”for students majoring in mineral processing engineering in universities,with coal and other sources of energy as the main focus.This paper analyzes the purpose and significance of setting up this course and the exploration of the reform of the teaching mode,with the aim of improving the teaching quality and ensuring the cultivation of mineral processing engineering undergraduates.展开更多
1 Introduction The large clusters of Zn-Pb deposits in northeastern Yunnan,located in the southwestern margin of the Yangtze Block,are an important part of the Sichuan-YunnanGuizhou Pb-Zn Poly-metallic Metallogenic Tr...1 Introduction The large clusters of Zn-Pb deposits in northeastern Yunnan,located in the southwestern margin of the Yangtze Block,are an important part of the Sichuan-YunnanGuizhou Pb-Zn Poly-metallic Metallogenic Triangle Area展开更多
More than 40 kinds of selected minerals and compounds were individually irradiated by microwaves under an inert atmosphere,and the temperatures of samples were measured with a metal-sheathed thermocouple inserted into...More than 40 kinds of selected minerals and compounds were individually irradiated by microwaves under an inert atmosphere,and the temperatures of samples were measured with a metal-sheathed thermocouple inserted into the samples directiy.The results indicated that most sulphide and some oxide minerals and compounds could be heated to high temperatures in a short timet whereas the common gangue minerals,some oxide and oxy-salt minerals or compounds could not.The sulphide minerals had faster heating rate than the oxide minerals containing the same cations.The impurities of minerals had significant effect on the heating rate.The selective heating characteristics of microwaves on different minerals and compounds could be attributed to the differences between their conductivities or dielectric loss factors and bonding properties.展开更多
Spatially superimposed multiple processes such as multiplicative cascade processes often generate multifractal measures possessing so-called self-similarity or self-affinity that can be described by power- law type of...Spatially superimposed multiple processes such as multiplicative cascade processes often generate multifractal measures possessing so-called self-similarity or self-affinity that can be described by power- law type of functions within certain scale ranges The multifractalities can be estimated by applying multifractal modeling to the measures reflecting the characteristics of the physical processes such as the element concentration values analyzed in rock and soil samples and caused by the underlying mineralization processes and the other geological processes. The local and regional geological processes may result in geochemical patterns with distinct multifractalities as wall as variable scaling ranges. Separation of these multifractal measures on the basis of both the distinct multifractalities and the scaling ranges will be significant for both theoretical studies of multifractal modeling and its applications. Multifractal scaling breaks have been observed from various multifractal patterns. This paper introduces a technique for separating multifractal measures on the basis of scaling breaks. It has been demonstrated that the method is effective for decomposing geochemical and geophysical anomalies required for mineral exploration. A dataset containing the element concentration values of potassium and phosphorus in soil samples was employed for demonstrating the application of the method for studying the fertilizer and yield optimization in agriculture展开更多
The Cr:Fe ratio (chromium-to-iron mass ratio) of chromite affects the production of chrome-based ferroalloys. Although the lit- erature contains numerous reports related to the magnetic separation of different mine...The Cr:Fe ratio (chromium-to-iron mass ratio) of chromite affects the production of chrome-based ferroalloys. Although the lit- erature contains numerous reports related to the magnetic separation of different minerals, limited work concerning the application of mag- netic separation to fine chromite from the Sukinda region of India to enhance its Cr:Fe ratio has been reported. In the present investigation, magnetic separation and mineralogical characterization studies of chromite fines were conducted to enhance the Cr:Fe ratio. Characterization studies included particle size and chemical analyses, X-ray diffraction analysis, automated mineral analysis, sink-and-float studies, and mag- netic susceptibility measurements, whereas magnetic separation was investigated using a rare earth drum magnetic separator, a rare earth roll magnetic separator, an induced roll magnetic separator, and a wet high-intensity magnetic separator. The fine chromite was observed to be upgraded to a Cr:Fe ratio of 2.2 with a yield of 55.7% through the use of an induced roll magnetic separator and a feed material with a Cr:Fe ratio of 1.6.展开更多
In combination with the Bagnold's shearing theory and the principle of Markov process,a mathematical model of sluice type's gravity concentrators has been developed based on the transfer probabilities of miner...In combination with the Bagnold's shearing theory and the principle of Markov process,a mathematical model of sluice type's gravity concentrators has been developed based on the transfer probabilities of mineral particles.According to the transfer probabilities,the quanti- tative relationship between the final separation results and feed variables has been established and verified by experimental data.The availability of this model is vital for process design and optimization or mill control of gravity concentration circuits.展开更多
The Agios Athanasios ore deposit is located within the wider area of Ieropigi in Kastoria, Greece. The specific ore deposit is developed in form of layers between ophiolites and Tertiary molassic conglomerates. The ma...The Agios Athanasios ore deposit is located within the wider area of Ieropigi in Kastoria, Greece. The specific ore deposit is developed in form of layers between ophiolites and Tertiary molassic conglomerates. The main mineralogical components are hematite, goethite, quartz, and secondarily, garnierite, lizardite, saponite, willemzeite and sepiolite, while scarcers are chromite, calcite and nepouite. Nickel is mainly found in garnierite, willemzeite and nepouite, which in coexistence with quartz are the main components in the binder material of the ore. For the mineral processing gravimetric and magnetic separations are used in the size of fractions -8 + 4 mm, -4 + 1 mm, -1 + 0.250 mm and -0.250 + 0.063 mm. The chemical and mineralogical analysis in combination with microscopic examination showed that mineral processing by gravimetric separation gave the most satisfactory results for the size fraction -1 + 0.250 mm.展开更多
文摘Microtextures and struetures of 9 hydrothermal chimneys sampled on the small spreading ridge Of the Mari ana Trough during SONNE Cruise 57 (SO57) and 69 (SO69) in 1988 and 1990 were studied by means of scanning electron microscope. The results reveal that the two types of chimneys from the Mariana Trough. the 'silicic chimneys' containing Fe sulfide and the pure 'silica chimneys' without sulfide, vary distinctly not only in mineral and chemical compositions, but also in microtextures and structures. The silicic chimneys generally show three major types of microtextures.The inside of the chimneys is dominated by holocrystalline or semicrystalline idiomorphic and hypidiomorphic granular textures and the outwall by amorphous colloidal texture. In some of the silicic chimneys relict texture is observed. However,the pure silica chimneys show chiefly amorphous colloidal texture from the inside to the outwall. Microstructurally. theinside of the silicic chimneys is dominated by a 'silica-covering' structure and a 'voidfilling' structure, and the outwall by a chain-like or three-dimentional chain-network structure built up by individual opal globules, whereas the pure silica chimneys are mainly three-dimentional chain-network and the dense silica bands in structure. These variations suggest that not only mineralizing conditions but also processes differ distinctly during the formation of the two types of chimneys, and that hydrothermal mineralization in the Mariana Trough shows a multistage or multieplsodical nature.
文摘White sandstone samples from Hanout area of Late Cambrian-Early Ordovician sandstone in south of Jordan were studied and assessed as a source of glass sand. Upgrading the sand included removing or reducing the content of the contaminant oxides and the heavy minerals. The aim of this research was to achieve this upgrading by examining the best-suited and cost-effective processing method(s) with sufficient product recovery. Following the initial sample characterisation at “bench scale”, a pilot study was performed. A high-grade Glass Sand product of 500 - 125 μm size fraction was produced by wet screening, attrition scrubbing and the separation of heavy minerals using spirals. The high quality Glass Sand product compared well with Grade-A of the British Standard for glass sand. Due to the relatively low level of impurities in the raw material, a substantial silica sand recovery was produced with a high silica grade. The silica sand product was capable to be used in the high quality glass industry and in many other applications where pure silica is required. The mass flowrate of the feeds and the products in the spiral was calculated for the bulk sample as well as the amount of water required operating the process.
基金This work was supported by The Graduate Education and Teaching Reform Project of CUMTB(YJG202200301)The Yueqi Outstanding Scholar Award of CUMTB and Science and Technology Major Project of Ordos City-Iconic Innovation Team(202204).
文摘In order to gain practical experience and hands-on skills,full-time professional master degree postgraduate in mineral processing engineering should engage in professional practices.Nonetheless,a series of problems,including insufficient time for practice,low management level,inadequate implementation of the double-supervisor system,and poor results of professional practice,has reduced the effectiveness of professional practice.In view of the aforementioned problems and the characteristics of the discipline,this paper proposes several strategies for improving the effectiveness of professional practice for postgraduates in mineral processing engineering.
文摘A better understanding of solid-liquid separation would assist in improving the thickening performance and perhaps water recovery as well. The present work aimed to develop an empirical model to study the effects of ore properties on the thickening process based on pilot tests using a column. A hydro-cyclone was used to prepare the required samples for the experiments. The model significantly predicted the experimental underflow solid content using a regression equation at a given solid flux and bed level for different samples, indicating that ore properties are the effective parameters in the thickening process. This work confirned that the water recovery would be increased about 5% by separating the feed into two parts, overflow and underflow, and introducing two different thickeners into them separately. This is duo to the fact that thickeners are limited by permeability and compressibility in operating conditions.
文摘The latest progress in mineral processing in China is described. It is also pointed out that the existing technology can not meet the needs of economic development. The combined challenges of poor resources, economical benefits and environmental pollution issues require further research to upgrade the separation efficiency economically. The methods of mineral processing should play a more important part in waste treatment such as wastewater treatment, the remediation of contaminated soil and the recycling of wastes. Biomineral technology will be utilised in the near future.
基金financially supported by the National Natural Science Foundation of China(grant No.41302061)
文摘Rare metal ore reserves are an important strategic resource, and their metallogenic mechanism and mineralization studies have also been received widespread international attention.
基金funded by the National Natural Science Foundation of China(Grant No.41172047)the Open Fund of the Key Laboratory of Ore Deposit Geochemistry(Institute of Geochemistry,Chinese Academy of Sciences,Guiyang),(Grant No.201308)the Open Fund of the Key Laboratory Metallogeny and Mineral Resource Assessment,Ministry of Land and Resources(Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing)(Grant No.ZS1407)
文摘Spinel exsolution is widespread in titanomagnetite from the Fe-Ti oxide gabbro of the Panzhihua intrusion, Emeishan Large Igneous Province, SW China. However, little research has been conducted into the implications of patterns in the mineralogical characteristics of the spinel for spatial variation in the controls on the exsolution mechanism and, hence, the formation process of the ore deposit. This study selected the Lanjiahuoshan Ore Block in the Panzhihua V-Ti magnetite deposit to explore this issue, systematically studying exsolution textures in the titanomagnetite through petrographic observation and the integrated use of in-situ microanalysis. The results show that the exsolved spinel gradually becomes finer-grained and less abundant from the center to edge and the bottom to top of the ore bodies. Compositionally, there is an inverse correlation between the size of exsolved spinel grains and their Mg# value. In addition, there is compositional zonation in the spinel interiors, with a gradual increase in the Mg content and decrease in Fe content from the core to the rim. The analysis suggests that fractional crystallization of ferrotitanium magma with a high oxygen fugacity in a shallow magma chamber caused compositional differences in the primary magnetite solid solution in different parts of the Panzhihua intrusion. Additionally, the thermal evolution of the magnetite solid solution differed in different parts of orebody, bringing about variations in spinel development. Together, these effects resulted in spatial variation in the abundance, grain size, and morphology of spinel in different parts of the orebody and intrusion that follows an identifiable distribution law. Furthermore, the compositional zonation of exsolved spinels reflects the rapid growth of exsolution features in a high-temperature environment. Thus, the size, morphology, abundance, and composition of spinel exsolution features in titanomagnetite provide a valuable petrogenetic tool for estimating the maturity and formational environment of the deposit.
文摘The first International Conference on Modern Process Mineralogy and Mineral Processing, organized by the Nonferrous Metals Society of China and hosted by Beijing General Research Institute of Mining and Metallurgy,was held on September 22-25,1992,in Beijing,China.About 350 scholars and experts from 25 countries and regions showed up at the conference and 130 papers were presented,among them 98 papers are of mineral processing.Some of the papers given in mineral processing are summed up as follows.
基金Funded by the National Natural Science Foundation of China(No.46120511)。
文摘The effects of various general and heavy metal ions in acidic cadmium-containing wastewater on SBR desulfurization and cadmium removal under different concentrations were studied.CrO_(4)^(2-) and S^(2-) inhibited SRB mineralization,and Mg^(2+),Ca^(2+),Fe^(2+),and Fe^(3+) promoted SRB mineralization at low concentration(<50 mg/L).The inhibitory concentrations of Cu^(2+),Mn^(2+),Co^(2+),Zn^(2+),Pb^(2+),Hg^(2+),Cr^(3+),and Ni^(2+) were 10,30,2,20,25,5,30 mg/L,respectively.The inhibition order was Co^(2+)>Hg^(2+)>Cu^(2+)>Ni^(2+)>Zn^(2+)>Pb^(2+)>Mn^(2+)>Cr^(3+).Furthermore,the inverted microscopy and scanning electron microscopy(SEM)were used to observe the sediment crystallization process from macroscopic and microscopic viewpoints in the optimized ion environment.The experimental results show that under the mineralization of SRB,cadmium sediment crystallization is mainly divided into the rapid growth of bacteria,crystal nucleus production,block formation,and crystallization occuration.At the same time,X-ray diffraction(XRD)and energy-dispersive spectra(EDS)have also confirmed the sediment and crystallization.
文摘1 Introduction Studies of marine sedimentary phosphate rock have lasted decades,scholars proposed some standpoints about mineralization,however,the genesis of mineral deposits remains to be a controversial question(She et al.,2013).There are many viewpoints of mineralization about the Doushantuo phosphorites,Central Guizhou,including biological mineralization(Mi et al.,2010;Shi et al.,2005),
基金This study was financially supported by the Undergraduate Education and Teaching Research and Reform Project of CUMTB(J20ZD08,202112)the Yueqi Outstanding Scholar Award of CUMTB.
文摘Social economic growth and the increasing demand for mineral resources have promoted the development of metallic mineral processing technology.Therefore,in order to satisfy the demands for development in mining,cultivating comprehensive mineral processing engineering professionals with strong innovative practical skills has become the top priority in current education.We have established a new course,“Metallic Mineral Processing,”for students majoring in mineral processing engineering in universities,with coal and other sources of energy as the main focus.This paper analyzes the purpose and significance of setting up this course and the exploration of the reform of the teaching mode,with the aim of improving the teaching quality and ensuring the cultivation of mineral processing engineering undergraduates.
基金supported by the Funds for the program of the National Natural Science Foundation (Noes. 41572060, U1133602)Projects of YM Lab (2011)Innovation Team of Yunnan province and KMUST (2008,2012)
文摘1 Introduction The large clusters of Zn-Pb deposits in northeastern Yunnan,located in the southwestern margin of the Yangtze Block,are an important part of the Sichuan-YunnanGuizhou Pb-Zn Poly-metallic Metallogenic Triangle Area
基金Supported by the National Natural Science Foundation and National Nonferrous Metals Industry Corporation of China。
文摘More than 40 kinds of selected minerals and compounds were individually irradiated by microwaves under an inert atmosphere,and the temperatures of samples were measured with a metal-sheathed thermocouple inserted into the samples directiy.The results indicated that most sulphide and some oxide minerals and compounds could be heated to high temperatures in a short timet whereas the common gangue minerals,some oxide and oxy-salt minerals or compounds could not.The sulphide minerals had faster heating rate than the oxide minerals containing the same cations.The impurities of minerals had significant effect on the heating rate.The selective heating characteristics of microwaves on different minerals and compounds could be attributed to the differences between their conductivities or dielectric loss factors and bonding properties.
文摘Spatially superimposed multiple processes such as multiplicative cascade processes often generate multifractal measures possessing so-called self-similarity or self-affinity that can be described by power- law type of functions within certain scale ranges The multifractalities can be estimated by applying multifractal modeling to the measures reflecting the characteristics of the physical processes such as the element concentration values analyzed in rock and soil samples and caused by the underlying mineralization processes and the other geological processes. The local and regional geological processes may result in geochemical patterns with distinct multifractalities as wall as variable scaling ranges. Separation of these multifractal measures on the basis of both the distinct multifractalities and the scaling ranges will be significant for both theoretical studies of multifractal modeling and its applications. Multifractal scaling breaks have been observed from various multifractal patterns. This paper introduces a technique for separating multifractal measures on the basis of scaling breaks. It has been demonstrated that the method is effective for decomposing geochemical and geophysical anomalies required for mineral exploration. A dataset containing the element concentration values of potassium and phosphorus in soil samples was employed for demonstrating the application of the method for studying the fertilizer and yield optimization in agriculture
文摘The Cr:Fe ratio (chromium-to-iron mass ratio) of chromite affects the production of chrome-based ferroalloys. Although the lit- erature contains numerous reports related to the magnetic separation of different minerals, limited work concerning the application of mag- netic separation to fine chromite from the Sukinda region of India to enhance its Cr:Fe ratio has been reported. In the present investigation, magnetic separation and mineralogical characterization studies of chromite fines were conducted to enhance the Cr:Fe ratio. Characterization studies included particle size and chemical analyses, X-ray diffraction analysis, automated mineral analysis, sink-and-float studies, and mag- netic susceptibility measurements, whereas magnetic separation was investigated using a rare earth drum magnetic separator, a rare earth roll magnetic separator, an induced roll magnetic separator, and a wet high-intensity magnetic separator. The fine chromite was observed to be upgraded to a Cr:Fe ratio of 2.2 with a yield of 55.7% through the use of an induced roll magnetic separator and a feed material with a Cr:Fe ratio of 1.6.
文摘In combination with the Bagnold's shearing theory and the principle of Markov process,a mathematical model of sluice type's gravity concentrators has been developed based on the transfer probabilities of mineral particles.According to the transfer probabilities,the quanti- tative relationship between the final separation results and feed variables has been established and verified by experimental data.The availability of this model is vital for process design and optimization or mill control of gravity concentration circuits.
文摘The Agios Athanasios ore deposit is located within the wider area of Ieropigi in Kastoria, Greece. The specific ore deposit is developed in form of layers between ophiolites and Tertiary molassic conglomerates. The main mineralogical components are hematite, goethite, quartz, and secondarily, garnierite, lizardite, saponite, willemzeite and sepiolite, while scarcers are chromite, calcite and nepouite. Nickel is mainly found in garnierite, willemzeite and nepouite, which in coexistence with quartz are the main components in the binder material of the ore. For the mineral processing gravimetric and magnetic separations are used in the size of fractions -8 + 4 mm, -4 + 1 mm, -1 + 0.250 mm and -0.250 + 0.063 mm. The chemical and mineralogical analysis in combination with microscopic examination showed that mineral processing by gravimetric separation gave the most satisfactory results for the size fraction -1 + 0.250 mm.