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Selective extraction of zinc from sulfate leach solution of zinc ore

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中国有色金属学会会刊：英文版 2003年第6期13卷 1435-1439页

作者：覃文庆蓝卓越黎维中邱冠周 School of Minerals processing and Bioengineering

Selective extraction of zinc from sulfate leach solution of zinc ore was studied. D2EHPA dissolved in 260#kerosene was used as extractant. The pH-extraction isotherms show the extraction order of D2EHPA for metals is Fe3+>Zn2+>Ca2+>Al3+>Mn2+>Cu2+>Cd2+>Co2+>Ni2+>Mg2+(pH0.5). This confirms that Fe3+ is preferentially extracted before the extraction of zinc. Extraction experiments were carried out with varying the extractant content, equilibration time, aqueous pH and phase ratio, and the solvent extraction of zinc with sodium salt of D2EHPA were also investigated. Some impurity co-extracted into the zinc loaded organic phase was efficiently removed by scrub, and the Fe3+ was hardly stripped from organic phase by sulfuric acid, hence zinc was separated from Fe3+ by selective stripping. A pregnant zinc sulfate solution with low contaminants was obtained by selective solvent extraction.

关键词：锌选择性萃取浸出硫酸盐滤液

Improving gold recovery of Pb–Zn sulfide ore by selective activation with organic acid

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Rare Metals 2016年第2期35卷 198-203页

作者： Dai-Xiong Chen Jun Xiao School of Minerals processing and Bioengineering Central South University Hunan Provincial Key laboratory of Complex Copper Lead Zinc Associated Metal Resources Comprehensive Utilization Hunan Research Institute for Nonferrous Metals

Free gold and gold wrapped in sulfides are considered as the object of gold floatation. However,floatation of free gold exhibits more variables in *** this study, improving gold recovery of a Pb-Zn sulfide ore from Yunnan Province, China, was investigated. The results show that free gold and auriferous sulfides account for 94.99 % of total gold. Without adding organic acid in floatation, only 82 % recovery of gold could be *** recovery in Au/Pb concentrates increases by 9.29 %with oxalate added and by 7.35 % with citric acid added,respectively, while performances of lead and arsenic nearly keep a constant. A possible reason is that free gold is of wonderful selectivity against pyrite with organic activators.A new method to enhance gold recovery is proposed.

关键词： Gold Improving recovery Pb-Zn sulfide ore Selective activation Organic acid

Growth behavior of the magnetite phase in the reduction of hematite via a fluidized bed

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International Journal of Minerals,Metallurgy and Materials 2019年第10期26卷 1231-1238页

作者： Jian-wen Yu Yue-xin Han Yan-jun Li Peng Gao School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China State Key laboratory of Mineral processing Beijing General Research Institute of Mining&Metallurgy GroupBeijing 102628China

To understand the formation and growth mechanism of the magnetite phase during the fluidized reduction of hematite, a high-purity hematite ore was isothermally reduced using a 20vol% CO 80vol% CO2 gas mixture in a micro-fluidized bed to examine the process of the selective conversion of hematite to magnetite. The micro-structural characteristics of the magnetite phase were investigated using scanning electron microscopy (SEM) and the Brunauer, Emmett, and Teller (BET) method, and the thickness of the magnetite layer was measured and evaluated using statistical analysis. The experimental results showed that the fresh magnetite nuclei were dense needles of different lengths, and the original hematite grains became porous after complete reduction to the magnetite phase. The thickness of the mag- netite layer increased with an increase in reduction temperature and reduction time. The growth kinetics of the magnetite layer was investi- gated, and the value of the activation energy E was estimated to be 28.33 kJ/mol.

关键词： hematite ore fluidized bed suspension magnetization roasting magnetite growth kinetics

Mathematical models and expert system for grate-kiln process of iron ore oxide pellet production(Part Ⅰ):Mathematical models of grate process

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Journal of Central South University 2012年第4期19卷 1092-1097页

作者：王祎范晓慧陈许玲 School of Minerals processing and Bioengineering Central South University

Grate process is an important step in grate-kiln pellet ***,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to *** 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 *** real-time visualization of temperature,moisture and oxidation degree distribution in pellet bed during grate process is *** validation is displayed,and the similarity of 91% is *** 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.

关键词： mathematical model temperature distribution moisture distribution oxidation degree distribution iron ore oxide pellet

Combustion behavior and influence mechanism of CO on iron ore sintering with flue gas recirculation

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Journal of Central South University 2014年第6期21卷 2391-2396页

作者：范晓慧余志元甘敏陈许玲季志云 School of Minerals processing and Bioengineering Central South University

The properties of circulating gas have a significant effect on sintering with flue gas recirculation,and the influence of CO in sintering process was *** results show that the post-combustion of CO conducts in sinter zone when flue gas passes through the sintering bed,which releases much heat and reduces the consumption of solid *** ratio of coke breeze can be reduced from 5% to 4.7% with 2% CO in circulating flue *** addition,with the increase of CO content in circulating flue gas,the combustion efficiency of fuel is improved,and the flame front is increased slightly while still matches with the heat transfer *** are beneficial to increasing the maximum temperature and prolonging the high temperature duration,especially in the upper layer of sintering *** a consequence,the productivity,vertical sintering velocity and quality of sinter are improved.

关键词： flue gas recirculation heat transfer front flame front combustion behavior

Calcium ferrite formation characteristic during iron ore sintering with different oxygen atmospheres

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Journal of Central South University 2014年第8期21卷 3043-3048页

作者：毛晓明游志雄张元波范振宇李光辉姜涛 School of Minerals processing & Bioengineering Central South University

It is generally known that the large formation amount of calcium ferrite is favorable for the iron ore sintering. The effects of sintering temperature and O2 content of inlet gas on the calcium ferrite formation characteristic of typical iron ores, including hematite, limonite, specularite and magnetite, were investigated. And the effect of O2 content on the microstructure of the roasted briquettes was also studied in detail. The results show the amount of calcium ferrite initially increases then decreases with the increase of the sintering temperature. The temperature of maximum calcium ferrite generation amount is determined as follows： for hematite and limonite it is 1275 ~C, whereas for specularite and magnetite, 1250℃. The maximum contents of calcium ferrite for hematite, limonite, specularite and magnetite under the optimal sintering temperature are 73%, 82%, 67% and 63%, respectively. Increasing O2 content of the airflow is advantageous to the formation of calcium ferrite. Relatively, the effect of O2 content on the calcium ferrite formation of magnetite is the most pronounced, while O2 content of inlet gas has little effect on the calcium ferrite formation of limonite.

关键词： iron ore sintering calcium ferrite mineralization

Influence of O_2 Content in Circulating Flue Gas on Iron ore Sintering

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Journal of Iron and Steel Research International 2013年第6期20卷 1-6页

作者： FAN Xiao-hui YU Zhi-yuan GAN Min LI Wen-qi JI Zhi-yun School of Minerals processing and Bioengineering Central South University

Circulating flue gas can reduce the emission of flue gas , and furthermore , it can reuse the waste heat effectively in the sintering *** with conventional sintering , O2 that gets through the sintering bed decreases because of substituting circulating gas for *** influences of O2 content on sintering process are studied through simulating the flue gas circulation sintering with artificial *** shows that , with the reducing of O2 content in circulating gas , the combustion speed of fuel decreases and incomplete combustion degree increases , which makes the flame front fall behind the heat front and reduces the heat utilization efficiency of *** ultimate result is that the temperature of sintering bed decreases and the liquid phase *** addition , the reducing atmosphere is strengthened because of flue gas circulation , which makes the magnetite increase yet calcium ferrite reduce gradually. Because the content of calcium ferrite with good strength reduces , the sinter yield and tumble strength *** ensure the sinter index , the favorable O2 content of circulating flue gas is no less than 15%.

关键词： flue gas circulation sintering heat front flame front sintering metallogenium

Mechanochemical sulfidization of a mixed oxide-sulphide copper ore by co-grinding with sulfur and its effect on the flotation efficiency

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Chinese Journal of Chemical Engineering 2020年第3期28卷 743-748页

作者： Mojtaba Masdarian Asghar Azizi Zahra Bahri Faculty of Mining Petroleum and GeophysicsShahrood University of TechnologyShahroodIran Department of Control and Modeling of Mineral processing Systems Institute of Mineral ProcessingACECR at Tarbiat ModaresTehranIran

Mechanochemical sulfidization of a mixed sulfide/oxide copper ore by co-grinding with sulfur and additives including Mg(NO3)2 and Fe(NO3)3 salts and iron,aluminum and magnesium powders was investigated for the first ***,the influence of sulfidization during the wet-milling process was examined on the separation efficiency and recovery of copper in *** results demonstrated that co-grinding with sulfur solely had the best flotation performance at the value of 0.5 wt.%and it was attributed to the possible existence of S\\O bonding on copper oxides *** addition,adding magnesium nitrate salt,magnesium powder,iron nitrate salt and aluminum powder as additive associated with 0.5 wt%sulfur into ball milling caused the flotation improvement at the amounts of 0.2 wt%,0.2 wt%,0.5 wt%and 0.5 wt%,***,the effect of grinding time and sulfidization pH with 0.5 wt%sulfur solely was determined and pH s of 7.5 to 8.5 gave the best *** highest recovery(75.76%)and separation efficiency(63.44%)were achieved at pH of 7.5 and 8.5,respectively.

关键词： Sulphide/oxide copper ore Floatability Mechanochemical sulfidization Reductive additives Recovery

Effect of H_2O(g)Content in Circulating Flue Gas on Iron ore Sintering with Flue Gas Recirculation

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Journal of Iron and Steel Research International 2015年第12期22卷 1107-1112页

作者： Xu-ling CHEN Yun-song HUANG Min GAN Xiao-hui FAN Zhi-yuan YU Li-shun YUAN School of Minerals processing and Bioengineering Central South University

The influence of H2O （g） content in circulating flue gas on sintering was studied by simulating the flue gas circulating sintering. The results show that the burning speed of solid fuel and the heat transfer rate during sintering process are improved when the H2O （g） content increases from 0 to 6%, which accelerates the sintering speed. However, when the H2O （g） content exceeds 6 %, the over-wet zone in sinter bed is thickened, which deteriorates the permeability of sintering bed. In addition, the magnetite content in sinter increases, while the acicular calcium ferrite content decreases. Accordingly, the sinter yield and tumble index decrease with excessive H2O （g） content. To guarantee the yield and quality of sinter, the favourable H2O （g） content in circulating flue gas should be controlled to be less than 6%.

关键词： flue gas circulating sintering burning speed heat front flame front sinter