The patterns of metal distribution and alteration zonation in magmatic-hydrothermal systems primarily focus on porphyry deposit and other closely associated types,such as skarn,epithermal and distal vein deposits(e.g....The patterns of metal distribution and alteration zonation in magmatic-hydrothermal systems primarily focus on porphyry deposit and other closely associated types,such as skarn,epithermal and distal vein deposits(e.g.,Zheng,2022;Hutchison et al.,2020;Cooke et al.,2011;Hedenquist et al.,1998).展开更多
In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics...In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics.Given copper's extensive industrial applications,sustainable recovery from low-grade ores is critical.Five key parameters-acid concentration,leaching time,particle size,temperature,and solids percentage-were identified as major influences on copper recovery.The results revealed that leaching time and solids percentage,along with interactions between temperature-time and temperature-solids percentage,had the most significant effects.Optimal conditions for 80% copper recovery while minimizing iron recovery below 3% included an acid concentration of 1.21 mol L^(-1),a leaching time of 108 min,a particle size of 438μm,a temperature of 45℃,and a solids percentage of 18.2%.Leaching kinetics were analyzed using shrinking core models,with the Dickinson model best describing the process,showing an activation energy of 32.63 kJ mol^(-1),indicative of mixed diffusion and chemical reaction control.The final kinetic model effectively predicted the influence of key parameters.These findings highlight the importance of optimizing process variables and selecting suitable kinetic models to enhance extraction efficiency,reduce costs,and improve sustainability in copper recovery.展开更多
Microwave roasting self-leaching is an innovative method for recovering gold from high-sulfur refractory gold concentrates,without using deadly toxic cyanide reagents.However,the mechanism of gold self-leaching,which ...Microwave roasting self-leaching is an innovative method for recovering gold from high-sulfur refractory gold concentrates,without using deadly toxic cyanide reagents.However,the mechanism of gold self-leaching,which relies on lixiviants prepared using volatilized sulfur obtained from roasting,has not been fully elucidated.This study employs the response surface methodology to optimize processing parameters,resulting in an increased gold extraction rate of 96.18%.Analytical factorization and the Tafel curve indicate that CuSO_(4) and NH_(3)·H_(2)O significantly influence the self-leaching process.Furthermore,X-ray photoelectron spectroscopy(XPS)analysis reveals that S^(2−),S_(2)^(2−),polysulfides(S_(n)^(2−)),and thiosulfate(S_(2)O_(3)^(2−))are involved in the gold leaching reaction,with S^(2−),S_(2)^(2−),and S_(n)^(2−) serving as primary ligands for gold complexation.The role of S_(2)O_(3)^(2−) in the early stages of the gold-leaching reaction is also noteworthy.The copper–ammonia complex catalyzes the self-leaching gold reaction;however,an improper addition ratio can lead to copper-sulfur compound precipitates,reducing the extraction rate.展开更多
Seabed mining operations have been found to induce significant movement and deformation in overlying rock strata,posing serious threats to mining safety.The presence of geological faults further complicates these defo...Seabed mining operations have been found to induce significant movement and deformation in overlying rock strata,posing serious threats to mining safety.The presence of geological faults further complicates these deformation patterns.This study utilized geophysical surveys and the continuum-based discrete element method(CDEM)to investigate how fault activity influences rock deformation and failure.The results demonstrate that:1)Acting in mechanically weak zones,faults exerted a pronounced barrier effect on deformation propagation and stress redistribution within the surrounding rock,leading to markedly divergent displacement patterns on either side of the fault plane.Comparative analyses between single-fault and double-fault models revealed an 18%−22%expansion of the damage zone under the latter,together with significantly intensified deformation and failure;2)The double-fault model exhibited a larger maximum cumulative vertical displacement and a spatial shift in the location of peak deformation,thereby posing a heightened threat to mine safety;3)Acting in an orebody substitute,backfill effectively constrained surrounding rock deformation,enhanced its load-bearing capacity,and delayed the overburden subsidence.Nevertheless,backfill only reduced the amplitude of deformation;it could not entirely prevent settlement.These findings provide essential theoretical insights and foundational knowledge for safer submarine mining practices.展开更多
Ida2--H2O system(iminodiacetate aqueous solution) was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio(L/S),total concentration of Ida2-([Ida2-]T),leachi...Ida2--H2O system(iminodiacetate aqueous solution) was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio(L/S),total concentration of Ida2-([Ida2-]T),leaching temperature and pH on Zn leaching recovery and the dissolution of impurities such as Ca,Mg,Cu,Ni,Fe,Pb and Cd were investigated.Results show that Ca,Mg and Fe in ores were hardly dissolved in alkalescent iminodiacetate aqueous solution,while valuable metals such as Cu,Ni,Pb and Cd were partly dissolved into leaching liquor with Zn.The recovery of Zn reaches 76.6% when the ores were leached for 4 h at 70 ℃ by 0.9 mol/L iminodiacetate aqueous solution with pH of 8 and L/S of 5:1.展开更多
Pyrolusite was added in the bioleaching process to enhance the bio-oxidation process. Bioleaching tests at different dosages of pyrolusite ore, pH and inoculation amounts of Acidithiobacillus ferrooxidans were studied...Pyrolusite was added in the bioleaching process to enhance the bio-oxidation process. Bioleaching tests at different dosages of pyrolusite ore, pH and inoculation amounts of Acidithiobacillus ferrooxidans were studied. The results showed that the time of the bio-oxidation process was decreased obviously and the arsenic leaching rate reached 94.4% after the bioleaching. The bio-oxidation of arsenopyrite and the effective extraction of manganese from pyrolusite were achieved by the bioleaching process. After bioleaching, the leaching rate of gold from the reaction residues reached 95.8% by cyanide leaching. In the bio-oxidation process, pyrolusite increased the redox potential of the solution to accelerate the bioleaching rate. The experiment showed that there were two reaction modes in the bioleaching process.展开更多
The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan h...The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan highsulfidation Cu-Au deposit,the Luoboling porphyry Cu-Mo deposit,the transitional style Cu deposit(Longjiangting and Wuziqilong)and the Yueyang low-sulfidation Agpolymetallic deposit(Zhang,2013;Zhang et al.,2003)展开更多
Using GIS, GPS and GPRS, a dynamic management system of ore blending in an open pit mine has been designed and developed. A linear program was established in a practical application. The system is very good at automat...Using GIS, GPS and GPRS, a dynamic management system of ore blending in an open pit mine has been designed and developed. A linear program was established in a practical application. The system is very good at automatically drawing up a daily production plan of ore blending and monitors and controls the process of mining production in real time. Experiments under real conditions show that the performance of this system is stable and can satisfy production standards of ore blending in open pit mines.展开更多
Located in the Qinling (秦岭) molybdenum metallogenic belt on the southern margin of North China craton, the Nannihu (南泥湖) molybdenum (-tungsten) ore field, consisting of the Nannihu, Sandaozhuang (三道幢),...Located in the Qinling (秦岭) molybdenum metallogenic belt on the southern margin of North China craton, the Nannihu (南泥湖) molybdenum (-tungsten) ore field, consisting of the Nannihu, Sandaozhuang (三道幢), and Shangfang (上房) deposits, represents a superlarge skarn-porphyry molybdenum (-tungsten) accumulation. Outside the ore field, there are some hydrothermal lead-zinc-silver deposits found in recent years, for example, the Lengshuibeigou (冷水北沟), Yindonggou (银涧沟), Yangshuwa (杨树凹), and Yinhegou (银河沟) deposits. Ore-forming fluid geochemistry indicates that these deposits belong to the same metallogenic system. The hydrothermal solutions were mainly derived from primary magmatic water in the early stage and from the mixture of the primary magmatic water and meteoric water in the later stage, with an obvious decreasing tendency in temperature, salinity and gas-liquid ratio of fluid inclusions. Sulfur and lead isotope data show that the ore-forming substances and related porphyries were mainly derived from the lower crust, and a hidden magmatic chamber is indicated by aeromagnetic anomaly and drill hole data indicate that the Nannihu granite body extends to being larger and larger with depth increasing. The large-scale mineralization was the consequence of lithospheric extension during the late stage of the tectonic regime when the main compressional stress changed from NS-trending to EW-trending.展开更多
Many theoretical results on sandstone-type uranium mineralization in northern China obtained by the uranium research team of the Tianjin Center of Geological Survey in recent years are presented.From the source sink s...Many theoretical results on sandstone-type uranium mineralization in northern China obtained by the uranium research team of the Tianjin Center of Geological Survey in recent years are presented.From the source sink system of uranium-producing basins,sedimentary environment of uranium-bearing rock series,ore-forming fluid information,evolution of tectonic events,basin formation and development,we redefine and classify uranium orebodies,redox zoning,and ore-controlling structural styles.We then systematically propose a theoretical system of sandstone-type uranium deposits in northern China.We conclude that sandstone-type uranium deposits in northern China are mainly found in sedimentary environments such as rivers,deltas,and alluvial fans in the Mesozoic and Cenozoic lowstand systems tract and in gray sandstone layers in the vertical redox zoning.The orebodies are controlled by the tectonic slope belt,which is in the shape of a strip on the plane,and spreads in a layer or plate on the section.Vertical(ups and downs)tectonic movement triggers large-scale phreatic flow in the basin,which is the real driving force for controlling the ore-forming fluid.The theoretical system of sandstone-type uranium deposits in northern China should be based on global tectonic movement and environmental changes and take into account factors such as basins as a unit to study mineralization background,ore concentration areas as objects to study mineralization,and the correlation between regional tectonic movement and metallogenic process as a breakthrough point to study tectonic events and metallogenic events.It should also be based on different basin types to establish metallogenic models.The innovative research results and ideas are summarized with the aim of promoting the continuous improvement of sandstone-type uranium mineralization theory in northern China.展开更多
A prompt gamma-neutron activation analysis(PGNAA) system was developed to detect the iron content of iron ore concentrate. Because of the self-absorption effect of gamma-rays and neutrons, and the interference of chlo...A prompt gamma-neutron activation analysis(PGNAA) system was developed to detect the iron content of iron ore concentrate. Because of the self-absorption effect of gamma-rays and neutrons, and the interference of chlorine in the neutron field, the linear relationship between the iron analytical coefficient and total iron content was poor, increasing the error in the quantitative analysis. To solve this problem, gamma-ray self-absorption compensation and a neutron field correction algorithm were proposed, and the experimental results have been corrected using this algorithm. The results show that the linear relationship between the iron analytical coefficient and total iron content was considerably improved after the correction. The linear correlation coefficients reached 0.99 or more.展开更多
A novel process was proposed for treating nickeliferous laterite ores with molten sodium hydroxide.The effect on silicon extraction caused by the factors,such as stirring speed,reaction temperature,particle size and N...A novel process was proposed for treating nickeliferous laterite ores with molten sodium hydroxide.The effect on silicon extraction caused by the factors,such as stirring speed,reaction temperature,particle size and NaOH-to-ore mass ratio,was investigated.The results show that increasing stirring speed,reaction temperature and NaOH-to-ore mass ratio while decreasing particle size increases silicon extraction rate.The desiliconization kinetics of nickeliferous laterite ores in molten sodium hydroxide system was described successfully by chemical reaction control model.The activation energy of the desiliconization process was found to be 44.01 kJ/mol,and the reaction rate based on a chemical reaction-controlled process can be expressed as:1-(1-α) 1/3 = 27.67exp[-44 010/(RT)]t.展开更多
Rotary kiln process for iron ore oxide pellet production is hard to detect and control.Construction of one-dimensional model of temperature field in rotary kiln was described.And the results lay a solid foundation for...Rotary kiln process for iron ore oxide pellet production is hard to detect and control.Construction of one-dimensional model of temperature field in rotary kiln was described.And the results lay a solid foundation for online control.Establishment of kiln process control expert system was presented,with maximum temperature of pellet and gas temperature at the feed end as control cores,and interval estimate as control strategy.Software was developed and put into application in a pellet plant.The results show that control guidance of this system is accurate and effective.After production application for nearly one year,the compressive strength and first grade rate of pellet are increased by 86 N and 2.54%,respectively,while FeO content is 0.05% lowered.This system can reveal detailed information of real time kiln process,and provide a powerful tool for online control of pellet production.展开更多
The leaching kinetics of low grade zinc oxide ore in NH3-NH4Cl-H2O system was studied. The effects of ore particle size, reaction temperature and the sum concentration of ammonium ion and ammonia on the leaching effic...The leaching kinetics of low grade zinc oxide ore in NH3-NH4Cl-H2O system was studied. The effects of ore particle size, reaction temperature and the sum concentration of ammonium ion and ammonia on the leaching efficiency of zinc were examined. The leaching kinetics of low-grade zinc oxide ore in NH3-NH4Cl-H2O system follows the kinetic law of shrinking-core model. The results show that diffusion through the inert particle pores is the leaching kinetics rate controlling step. The calculated apparent activation energy of the process is about 7.057 kJ/mol. The leaching efficiency of zinc is 92.1% under the conditions of ore particle size of 69 μm, holding at 80 ℃ for 60 min, sum ammonia concentration of 7.5 mol/L, the molar ratio of ammonium to ammonia being 2-1, and the ratio (g/mL) of solid to liquid being 1-10.展开更多
Pelletization is one of useful processes for the agglomeration of iron ore or concentrates. However, manganese ore fines are mainly agglomerated by sintering due to its high combined water which adversely affects the ...Pelletization is one of useful processes for the agglomeration of iron ore or concentrates. However, manganese ore fines are mainly agglomerated by sintering due to its high combined water which adversely affects the roasting performance of pellets. In this work, high pressure roll grinding(HPRG) process and optimization of temperature elevation system were investigated to improve the strength of fired manganese ore pellets. It is shown that the manganese ore possesses good ballability after being pretreated by HPRG twice, and good green balls were produced under the conditions of blending 2.0% bentonite in the feed, balling for 7 min at 16.00% moisture. High quality roasted pellets with the compressive strength of 2711 N per pellet were manufactured through preheating at 1050 °C for 10 min and firing at 1335 °C for 15 min by controlling the cracks formation. The fired manganese pellets keep the strength by the solid interconnection of recrystallized pyrolusite grains and the binding of manganite liquid phase which filled the pores and clearance among minerals. The product pellets contain high Mn grade and low impurities, and can be used to smelt ferromanganese, which provides a possible way to use imported manganese ore fines containing high combined water to produce high value ferromanganese.展开更多
Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematica...Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematical models of temperature distribution,moisture distribution and oxidation degree distribution in pellet bed,with good universality,computation speed and calculation accuracy,are presented based on analysis of heat transfer and physical-chemical reactions during grate process.And real-time visualization of temperature,moisture and oxidation degree distribution in pellet bed during grate process is realized.Model validation is displayed,and the similarity of 91% is proved.The results can reveal real time status on grate,and provide a solid foundation for the subsequent study of artificial intelligence control system of pellet production.展开更多
Based on characteristics of deep sea flexible mining system,a new pump-lockage ore transportation system was designed.According to Bernoulli equation and two-phase hydrodynamics theory,parameters of the new system wer...Based on characteristics of deep sea flexible mining system,a new pump-lockage ore transportation system was designed.According to Bernoulli equation and two-phase hydrodynamics theory,parameters of the new system were obtained and four ore transportation systems were analyzed.The results indicate that the pump head of 1 000 m mining system is 100-150 m and that of 5 000 m mining system is 660-750 m.In addition,based on similarity theory,a model of the new transportation system was made,which can simulate more than 5 000 m actual ore transportation system.So both theory and experiment prove that the new pump-lockage ore transportation system is an ideal design for deep sea flexible mining system.展开更多
ore deposits and a large number of ore occurrences cluster in Dexing ore field which is 20 km long and 12 km wide. The tectonic evolution, magmatism, as well as the metallogeny are controlled by the Northeast Jiangxi...ore deposits and a large number of ore occurrences cluster in Dexing ore field which is 20 km long and 12 km wide. The tectonic evolution, magmatism, as well as the metallogeny are controlled by the Northeast Jiangxi deep seated fracture belt (NJDFB). The source is believed to have been derived from the Meso-Neoproterozoic marine volcanism. The magmatic activity of Mesozoic I type granite could have provided the metal elements, thermal fluid, heat, and the space for ore forming processes. A unified geological model is proposed, which combines the tectonism, magmatism and metallogeny as the basic control of the giant metal mineralizations.展开更多
The discovery of new-type ore deposits, an important approach to guarantee the mineral resources supply in the 21st century, often brings about a gigantic increase in the mineral resources reserves. The analysis of mi...The discovery of new-type ore deposits, an important approach to guarantee the mineral resources supply in the 21st century, often brings about a gigantic increase in the mineral resources reserves. The analysis of mineralization system is of great importance to the discovery of new type ore deposits. ① The understanding of the relationship among various ore deposit types within a mineralization system in a region can help us to locate the unknown ore deposit types from the known ore deposit types, evidence that has been proved in the mineral prospecting history of ore belts in the middle and lower reaches of the Yangtze River, China. ② The understanding of the spatial structure of a mineralization system, especially of the vertical zonation, is helpful for the discovery of the concealed ore deposit types. ③ Clarifying the temporal structure of a mineralization system, including the iteration relationship between the mineral deposit types in the mineralization, leads to the location of the missing mineralization chains from the known mineralization chains (mineral deposit type), a method often proved to be effective in the magmatic hydrothermal mineralization system.④ Clarifying the factors restraining the diversity of mineral deposit types in mineralization system leads to the discovery of the potential of new type mineral deposits in relevant region. ⑤ Studying new mineralization setting and new ore forming processes leads to discovery of new type mineral deposit. More probabilities of discovery of new type mineral deposits are present in biogenic mineralization system, deep sea mineralization system, low temperature mineralization system, tectonic mineralization system and superimposed mineralization system.展开更多
The extraction of gold from refractory gold ores(RGOs)without side reactions is an extremely promising endeavor.However,most RGOs contain large amounts of sulfide,such as pyrite.Thus,investigation of the influence of ...The extraction of gold from refractory gold ores(RGOs)without side reactions is an extremely promising endeavor.However,most RGOs contain large amounts of sulfide,such as pyrite.Thus,investigation of the influence of sulfide on the gold leaching process is important to maximize the utilization of RGOs.In this work,the effects of pyrite on the stability of the thiourea system were systematically investigated under different conditions.Results showed that the decomposition rate of thiourea was accelerated sharply in the presence of pyrite.The effect of pyrite on gold recovery in thiourea leaching systems was then confirmed via a series of experiments.The decomposition efficiency of thiourea decreased by 40%and the recovery efficiency of gold increased by 56%after the removal of sulfide by roasting.Under optimal conditions,the efficiency of the gold recovery system increased to 83.69%and only 57.92%of thiourea decomposition was observed.The high consumption of thiourea by the leaching system may be attributed to not only adsorption by mineral particles but also catalytic decomposition by some impurities in the ores,such as pyrite and soluble ferric oxide.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42122012,U2444208)the Inner Mongolia Academician Project(No.2022-TZH03)the Fundamental Research Funds for the Central Universities(No.2652023001)。
文摘The patterns of metal distribution and alteration zonation in magmatic-hydrothermal systems primarily focus on porphyry deposit and other closely associated types,such as skarn,epithermal and distal vein deposits(e.g.,Zheng,2022;Hutchison et al.,2020;Cooke et al.,2011;Hedenquist et al.,1998).
基金Open Access funding enabled and organized by Projekt DEAL.
文摘In this study,copper extraction from low-grade oxide-sulfide ores was investigated using a leaching method combined with response surface methodology(RSM)to optimize operational conditions and assess leaching kinetics.Given copper's extensive industrial applications,sustainable recovery from low-grade ores is critical.Five key parameters-acid concentration,leaching time,particle size,temperature,and solids percentage-were identified as major influences on copper recovery.The results revealed that leaching time and solids percentage,along with interactions between temperature-time and temperature-solids percentage,had the most significant effects.Optimal conditions for 80% copper recovery while minimizing iron recovery below 3% included an acid concentration of 1.21 mol L^(-1),a leaching time of 108 min,a particle size of 438μm,a temperature of 45℃,and a solids percentage of 18.2%.Leaching kinetics were analyzed using shrinking core models,with the Dickinson model best describing the process,showing an activation energy of 32.63 kJ mol^(-1),indicative of mixed diffusion and chemical reaction control.The final kinetic model effectively predicted the influence of key parameters.These findings highlight the importance of optimizing process variables and selecting suitable kinetic models to enhance extraction efficiency,reduce costs,and improve sustainability in copper recovery.
基金supported by the National Natural Science Foundation of China(No.51974016).
文摘Microwave roasting self-leaching is an innovative method for recovering gold from high-sulfur refractory gold concentrates,without using deadly toxic cyanide reagents.However,the mechanism of gold self-leaching,which relies on lixiviants prepared using volatilized sulfur obtained from roasting,has not been fully elucidated.This study employs the response surface methodology to optimize processing parameters,resulting in an increased gold extraction rate of 96.18%.Analytical factorization and the Tafel curve indicate that CuSO_(4) and NH_(3)·H_(2)O significantly influence the self-leaching process.Furthermore,X-ray photoelectron spectroscopy(XPS)analysis reveals that S^(2−),S_(2)^(2−),polysulfides(S_(n)^(2−)),and thiosulfate(S_(2)O_(3)^(2−))are involved in the gold leaching reaction,with S^(2−),S_(2)^(2−),and S_(n)^(2−) serving as primary ligands for gold complexation.The role of S_(2)O_(3)^(2−) in the early stages of the gold-leaching reaction is also noteworthy.The copper–ammonia complex catalyzes the self-leaching gold reaction;however,an improper addition ratio can lead to copper-sulfur compound precipitates,reducing the extraction rate.
基金Project(42072305)supported by the National Natural Science Foundation of China。
文摘Seabed mining operations have been found to induce significant movement and deformation in overlying rock strata,posing serious threats to mining safety.The presence of geological faults further complicates these deformation patterns.This study utilized geophysical surveys and the continuum-based discrete element method(CDEM)to investigate how fault activity influences rock deformation and failure.The results demonstrate that:1)Acting in mechanically weak zones,faults exerted a pronounced barrier effect on deformation propagation and stress redistribution within the surrounding rock,leading to markedly divergent displacement patterns on either side of the fault plane.Comparative analyses between single-fault and double-fault models revealed an 18%−22%expansion of the damage zone under the latter,together with significantly intensified deformation and failure;2)The double-fault model exhibited a larger maximum cumulative vertical displacement and a spatial shift in the location of peak deformation,thereby posing a heightened threat to mine safety;3)Acting in an orebody substitute,backfill effectively constrained surrounding rock deformation,enhanced its load-bearing capacity,and delayed the overburden subsidence.Nevertheless,backfill only reduced the amplitude of deformation;it could not entirely prevent settlement.These findings provide essential theoretical insights and foundational knowledge for safer submarine mining practices.
基金Project (2007CB613604) supported by the National Basic Research Program of China
文摘Ida2--H2O system(iminodiacetate aqueous solution) was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio(L/S),total concentration of Ida2-([Ida2-]T),leaching temperature and pH on Zn leaching recovery and the dissolution of impurities such as Ca,Mg,Cu,Ni,Fe,Pb and Cd were investigated.Results show that Ca,Mg and Fe in ores were hardly dissolved in alkalescent iminodiacetate aqueous solution,while valuable metals such as Cu,Ni,Pb and Cd were partly dissolved into leaching liquor with Zn.The recovery of Zn reaches 76.6% when the ores were leached for 4 h at 70 ℃ by 0.9 mol/L iminodiacetate aqueous solution with pH of 8 and L/S of 5:1.
基金Project(2015ZX07205-003)supported by the National Water Pollution Control and Treatment Science,ChinaProject(DY125-15-T-08)supported by China Ocean Mineral Resource R&D Association+1 种基金Project(2012BAB07B05)supported by the National Key Technology R&D Program of ChinaProject(2012AA062401)supported by the National High-tech Research and Development Program of China
文摘Pyrolusite was added in the bioleaching process to enhance the bio-oxidation process. Bioleaching tests at different dosages of pyrolusite ore, pH and inoculation amounts of Acidithiobacillus ferrooxidans were studied. The results showed that the time of the bio-oxidation process was decreased obviously and the arsenic leaching rate reached 94.4% after the bioleaching. The bio-oxidation of arsenopyrite and the effective extraction of manganese from pyrolusite were achieved by the bioleaching process. After bioleaching, the leaching rate of gold from the reaction residues reached 95.8% by cyanide leaching. In the bio-oxidation process, pyrolusite increased the redox potential of the solution to accelerate the bioleaching rate. The experiment showed that there were two reaction modes in the bioleaching process.
基金financially supported by Zijin Mining Group(No.01612216)the Ministry of Natural Resources,China(No.ZKKJ202426)。
文摘The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan highsulfidation Cu-Au deposit,the Luoboling porphyry Cu-Mo deposit,the transitional style Cu deposit(Longjiangting and Wuziqilong)and the Yueyang low-sulfidation Agpolymetallic deposit(Zhang,2013;Zhang et al.,2003)
文摘Using GIS, GPS and GPRS, a dynamic management system of ore blending in an open pit mine has been designed and developed. A linear program was established in a practical application. The system is very good at automatically drawing up a daily production plan of ore blending and monitors and controls the process of mining production in real time. Experiments under real conditions show that the performance of this system is stable and can satisfy production standards of ore blending in open pit mines.
基金supported by the National Graduate Student Program of Building World-Class Universities (No. [2007]3020),China Scholarship CouncilState Key Laboratory of Geological Processes and Mineral Resources (No. GPMR200644), China University of Geosciences (Beijing)the National Natural Science Foundation of China (No. 40172036)
文摘Located in the Qinling (秦岭) molybdenum metallogenic belt on the southern margin of North China craton, the Nannihu (南泥湖) molybdenum (-tungsten) ore field, consisting of the Nannihu, Sandaozhuang (三道幢), and Shangfang (上房) deposits, represents a superlarge skarn-porphyry molybdenum (-tungsten) accumulation. Outside the ore field, there are some hydrothermal lead-zinc-silver deposits found in recent years, for example, the Lengshuibeigou (冷水北沟), Yindonggou (银涧沟), Yangshuwa (杨树凹), and Yinhegou (银河沟) deposits. Ore-forming fluid geochemistry indicates that these deposits belong to the same metallogenic system. The hydrothermal solutions were mainly derived from primary magmatic water in the early stage and from the mixture of the primary magmatic water and meteoric water in the later stage, with an obvious decreasing tendency in temperature, salinity and gas-liquid ratio of fluid inclusions. Sulfur and lead isotope data show that the ore-forming substances and related porphyries were mainly derived from the lower crust, and a hidden magmatic chamber is indicated by aeromagnetic anomaly and drill hole data indicate that the Nannihu granite body extends to being larger and larger with depth increasing. The large-scale mineralization was the consequence of lithospheric extension during the late stage of the tectonic regime when the main compressional stress changed from NS-trending to EW-trending.
基金The“Northern Sandstone-type Uranium Deposits Investigation Project”(Project 0108)of the China Geological Survey has led to the discovery of many new sandstone-type uranium depositsThe National Basic Research Program(973 Program)(No.2015CB453000)+1 种基金the National Key R&D Program of China(No.2018YFC0604200)both from the Ministry of Science and Technology of the People’s Republic of China have led to innovations in many theoretical understandings of sandstone-type uranium depositsUnder the International Geoscience Programme(No.IGCP-675),a comparative study of sandstone-type uranium deposits between China and the rest of the world has been conducted。
文摘Many theoretical results on sandstone-type uranium mineralization in northern China obtained by the uranium research team of the Tianjin Center of Geological Survey in recent years are presented.From the source sink system of uranium-producing basins,sedimentary environment of uranium-bearing rock series,ore-forming fluid information,evolution of tectonic events,basin formation and development,we redefine and classify uranium orebodies,redox zoning,and ore-controlling structural styles.We then systematically propose a theoretical system of sandstone-type uranium deposits in northern China.We conclude that sandstone-type uranium deposits in northern China are mainly found in sedimentary environments such as rivers,deltas,and alluvial fans in the Mesozoic and Cenozoic lowstand systems tract and in gray sandstone layers in the vertical redox zoning.The orebodies are controlled by the tectonic slope belt,which is in the shape of a strip on the plane,and spreads in a layer or plate on the section.Vertical(ups and downs)tectonic movement triggers large-scale phreatic flow in the basin,which is the real driving force for controlling the ore-forming fluid.The theoretical system of sandstone-type uranium deposits in northern China should be based on global tectonic movement and environmental changes and take into account factors such as basins as a unit to study mineralization background,ore concentration areas as objects to study mineralization,and the correlation between regional tectonic movement and metallogenic process as a breakthrough point to study tectonic events and metallogenic events.It should also be based on different basin types to establish metallogenic models.The innovative research results and ideas are summarized with the aim of promoting the continuous improvement of sandstone-type uranium mineralization theory in northern China.
基金supported by the National Key Scientific Instrument and Equipment Development Projects(No.2012YQ240121)Liaoning science and technology project(No.2017220010)Changchun Science and Technology Bureau Local Company and College(University,Institution)Cooperation Projects(No.17DY023)
文摘A prompt gamma-neutron activation analysis(PGNAA) system was developed to detect the iron content of iron ore concentrate. Because of the self-absorption effect of gamma-rays and neutrons, and the interference of chlorine in the neutron field, the linear relationship between the iron analytical coefficient and total iron content was poor, increasing the error in the quantitative analysis. To solve this problem, gamma-ray self-absorption compensation and a neutron field correction algorithm were proposed, and the experimental results have been corrected using this algorithm. The results show that the linear relationship between the iron analytical coefficient and total iron content was considerably improved after the correction. The linear correlation coefficients reached 0.99 or more.
基金Project(2007CB613603)supported by the National Basic Research Program of China
文摘A novel process was proposed for treating nickeliferous laterite ores with molten sodium hydroxide.The effect on silicon extraction caused by the factors,such as stirring speed,reaction temperature,particle size and NaOH-to-ore mass ratio,was investigated.The results show that increasing stirring speed,reaction temperature and NaOH-to-ore mass ratio while decreasing particle size increases silicon extraction rate.The desiliconization kinetics of nickeliferous laterite ores in molten sodium hydroxide system was described successfully by chemical reaction control model.The activation energy of the desiliconization process was found to be 44.01 kJ/mol,and the reaction rate based on a chemical reaction-controlled process can be expressed as:1-(1-α) 1/3 = 27.67exp[-44 010/(RT)]t.
基金Project(NCET-05-0630) supported by Program for New Century Excellent Talents in University of China
文摘Rotary kiln process for iron ore oxide pellet production is hard to detect and control.Construction of one-dimensional model of temperature field in rotary kiln was described.And the results lay a solid foundation for online control.Establishment of kiln process control expert system was presented,with maximum temperature of pellet and gas temperature at the feed end as control cores,and interval estimate as control strategy.Software was developed and put into application in a pellet plant.The results show that control guidance of this system is accurate and effective.After production application for nearly one year,the compressive strength and first grade rate of pellet are increased by 86 N and 2.54%,respectively,while FeO content is 0.05% lowered.This system can reveal detailed information of real time kiln process,and provide a powerful tool for online control of pellet production.
基金Project(2007CB613604) supported by the Major State Basic Research Development Program of ChinaProject(50674104) supported by the National Natural Science Foundation of ChinaProject(GJJ08279) supported by the Department of Education of Jiangxi Province
文摘The leaching kinetics of low grade zinc oxide ore in NH3-NH4Cl-H2O system was studied. The effects of ore particle size, reaction temperature and the sum concentration of ammonium ion and ammonia on the leaching efficiency of zinc were examined. The leaching kinetics of low-grade zinc oxide ore in NH3-NH4Cl-H2O system follows the kinetic law of shrinking-core model. The results show that diffusion through the inert particle pores is the leaching kinetics rate controlling step. The calculated apparent activation energy of the process is about 7.057 kJ/mol. The leaching efficiency of zinc is 92.1% under the conditions of ore particle size of 69 μm, holding at 80 ℃ for 60 min, sum ammonia concentration of 7.5 mol/L, the molar ratio of ammonium to ammonia being 2-1, and the ratio (g/mL) of solid to liquid being 1-10.
基金Project(2011GH561685)supported by the China Torch Program
文摘Pelletization is one of useful processes for the agglomeration of iron ore or concentrates. However, manganese ore fines are mainly agglomerated by sintering due to its high combined water which adversely affects the roasting performance of pellets. In this work, high pressure roll grinding(HPRG) process and optimization of temperature elevation system were investigated to improve the strength of fired manganese ore pellets. It is shown that the manganese ore possesses good ballability after being pretreated by HPRG twice, and good green balls were produced under the conditions of blending 2.0% bentonite in the feed, balling for 7 min at 16.00% moisture. High quality roasted pellets with the compressive strength of 2711 N per pellet were manufactured through preheating at 1050 °C for 10 min and firing at 1335 °C for 15 min by controlling the cracks formation. The fired manganese pellets keep the strength by the solid interconnection of recrystallized pyrolusite grains and the binding of manganite liquid phase which filled the pores and clearance among minerals. The product pellets contain high Mn grade and low impurities, and can be used to smelt ferromanganese, which provides a possible way to use imported manganese ore fines containing high combined water to produce high value ferromanganese.
基金Project(NCET050630) supported by Program for New Century Excellent Talents in University,China
文摘Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematical models of temperature distribution,moisture distribution and oxidation degree distribution in pellet bed,with good universality,computation speed and calculation accuracy,are presented based on analysis of heat transfer and physical-chemical reactions during grate process.And real-time visualization of temperature,moisture and oxidation degree distribution in pellet bed during grate process is realized.Model validation is displayed,and the similarity of 91% is proved.The results can reveal real time status on grate,and provide a solid foundation for the subsequent study of artificial intelligence control system of pellet production.
基金Project(50574100)supported by the National Natural Science Foundation of China
文摘Based on characteristics of deep sea flexible mining system,a new pump-lockage ore transportation system was designed.According to Bernoulli equation and two-phase hydrodynamics theory,parameters of the new system were obtained and four ore transportation systems were analyzed.The results indicate that the pump head of 1 000 m mining system is 100-150 m and that of 5 000 m mining system is 660-750 m.In addition,based on similarity theory,a model of the new transportation system was made,which can simulate more than 5 000 m actual ore transportation system.So both theory and experiment prove that the new pump-lockage ore transportation system is an ideal design for deep sea flexible mining system.
文摘ore deposits and a large number of ore occurrences cluster in Dexing ore field which is 20 km long and 12 km wide. The tectonic evolution, magmatism, as well as the metallogeny are controlled by the Northeast Jiangxi deep seated fracture belt (NJDFB). The source is believed to have been derived from the Meso-Neoproterozoic marine volcanism. The magmatic activity of Mesozoic I type granite could have provided the metal elements, thermal fluid, heat, and the space for ore forming processes. A unified geological model is proposed, which combines the tectonism, magmatism and metallogeny as the basic control of the giant metal mineralizations.
文摘The discovery of new-type ore deposits, an important approach to guarantee the mineral resources supply in the 21st century, often brings about a gigantic increase in the mineral resources reserves. The analysis of mineralization system is of great importance to the discovery of new type ore deposits. ① The understanding of the relationship among various ore deposit types within a mineralization system in a region can help us to locate the unknown ore deposit types from the known ore deposit types, evidence that has been proved in the mineral prospecting history of ore belts in the middle and lower reaches of the Yangtze River, China. ② The understanding of the spatial structure of a mineralization system, especially of the vertical zonation, is helpful for the discovery of the concealed ore deposit types. ③ Clarifying the temporal structure of a mineralization system, including the iteration relationship between the mineral deposit types in the mineralization, leads to the location of the missing mineralization chains from the known mineralization chains (mineral deposit type), a method often proved to be effective in the magmatic hydrothermal mineralization system.④ Clarifying the factors restraining the diversity of mineral deposit types in mineralization system leads to the discovery of the potential of new type mineral deposits in relevant region. ⑤ Studying new mineralization setting and new ore forming processes leads to discovery of new type mineral deposit. More probabilities of discovery of new type mineral deposits are present in biogenic mineralization system, deep sea mineralization system, low temperature mineralization system, tectonic mineralization system and superimposed mineralization system.
基金This work was financially supported by the National Natural Science Foundation of China(No.51922108)the Hunan Natural Science Foundation(No.2019JJ20031)the Hunan Key Research and Development Program(No.2019SK2061).
文摘The extraction of gold from refractory gold ores(RGOs)without side reactions is an extremely promising endeavor.However,most RGOs contain large amounts of sulfide,such as pyrite.Thus,investigation of the influence of sulfide on the gold leaching process is important to maximize the utilization of RGOs.In this work,the effects of pyrite on the stability of the thiourea system were systematically investigated under different conditions.Results showed that the decomposition rate of thiourea was accelerated sharply in the presence of pyrite.The effect of pyrite on gold recovery in thiourea leaching systems was then confirmed via a series of experiments.The decomposition efficiency of thiourea decreased by 40%and the recovery efficiency of gold increased by 56%after the removal of sulfide by roasting.Under optimal conditions,the efficiency of the gold recovery system increased to 83.69%and only 57.92%of thiourea decomposition was observed.The high consumption of thiourea by the leaching system may be attributed to not only adsorption by mineral particles but also catalytic decomposition by some impurities in the ores,such as pyrite and soluble ferric oxide.