检索结果-南通市图书馆

Testing the robustness of particle-based separation models for the magnetic separation of a complex skarn ore

International Journal of Mining Science and Technology 2022年第3期32卷 645-655页

作者： Lucas Pereira Max Frenzel Markus Buchmann Marius Kern Raimon Tolosana-Delgado K.Gerald van den Boogaart Jens Gutzmer Hemholtz-Zentrum Dresden-Rossendorf Helmholtz Institute Freiberg for Resource Technology09599 FreibergGermany German Aerospace Center Institute of Low-Carbon Industrial Processes03046 CottbusGermany TU Bergakademie Freiberg Institute for Stochastics09599 FreibergGermany

Physical separation processes are best understood in terms of the behaviour of individual ore particles.Yet,while different empirical particle-based separation modelling approaches have been developed,their predictive performance has never been tested under variable process conditions.Here,we investigated the predictive performance of a state-of-the-art particle-based separation model under variable feed composition for a laboratory-scale magnetic separation of a skarn ore.Two scenarios were investigated:one in which the mass flow of the different processing streams could be measured and one in which it had to be estimated from data.In both scenarios,the predictive models were sufficiently general to predict the process outcomes of new samples of variable composition.Nevertheless,the scenario in which mass flow could be measured was4%more precise in predicting mass balances.The process behaviour of minerals present at concentrations above 0.1%by weight could be accurately predicted.Our findings indicate the potential use of this method to minimize the costs of metallurgical testwork while providing in-depth understanding of the recovery behaviour of individual ore particles.Moreover,the method may be used to establish powerful tools to forecast mineral recoveries for partly new ore types at a running mining operation.

关键词： Metallurgical tests Particle-based separation modelling magnetic separation Cassiterite recovery

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Upgrade of nickel and iron from low-grade nickel laterite by improving direct reduction-magnetic separation process

引用

Journal of Iron and Steel Research(International) 2022年第8期29卷 1164-1175页

作者： Hong-yu Tian Zheng-qi Guo Ruo-ning Zhan Jian Pan De-qing Zhu Cong-cong Yang Liao-ting Pan Xue-zhong Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Beibu Gulf New Materials Co. Ltd.Beihai 536000GuangxiChina

Low-grade saprolite nickel laterite,characterized by complicated minerals composition and fine-grained and complex dissemination,was commonly treated with a low recovery efficiency of Ni and Fe by conventional methods.Hence,an improved direct reduction and magnetic separation process was proposed.Meanwhile,the mechanisms on the enhanced growth of the Ni-Fe particles and the phase transformation in the nickel laterite pellets were explored.The low-nickel concentrates as a nucleating agent can obviously decrease the activation energy for growth of Ni-Fe alloy particles during the improved direct reduction process from 197.10 to 154.81 kJ/mol when the low-nickel concentrates were added from 0 to 20%.Hence,it is able to decrease nucleation barrier,induce the growth of Fe-Ni alloy particles and increase their average size.As a result,the size of Ni-Fe particles in the pellets from less than 10 lm grew to more than 20 lm,which is beneficial for the full liberation and recovery of Ni and Fe in subsequent magnetic separation process.Therefore,the preferable Ni-Fe alloy concentrates with 6.44%Ni and 82.48%Fe can be prepared with corresponding recovery rates of 96.90%and 95.92%,respectively,when adding 20%low-nickel concentrates.

关键词： Nickel laterite Low-nickel concentrate Nucleating agent Growth kinetics Ni-Fe alloy Direct reduction magnetic separation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Localization of rare earth ions in an inhomogeneous magnetic field toward their magnetic separation

引用

Journal of Rare Earths 2022年第10期40卷 1598-1605页

作者： Barbara Fritzsche Zhe Lei Xuegeng Yang Kerstin Eckert TU Dresden Institute of Process Engineering and Environmental Technology01062DresdenGermany Helmholtz-Zentrum Dresden-Rossendorf(HZDR) Institute of Fluid DynamicsBautzner Landstrasse 40001328DresdenGermany

Efficient extraction and recycling methods are an important issue for rare earth elements(REE). The significant differences in their magnetic moments make magnetic separation a promising step. Although the magnetic field gradient manipulation of ions seemed to be impossible, the robust enrichment of some paramagnetic RE ions was found in the vicinity of the magnet. The studies in recent years resolved the physical paradox of why, despite the Brownian motion of the ions, there is a reproducible enrichment of RE ions in magnetic field gradients. The existence of trigger process and energy barrier was proved.However, these studies usually used only high paramagnetic ions, e.g., Dy(Ⅲ) or Ho(Ⅲ). This work verifies the theory of the possible magnetic separation for 8 different rare earth ions, respectively. For this purpose, concentration distribution in rare earth chloride solutions were measured using a MachZehnder interferometer. The magnetic field was assured by a Halbach configuration to enhance the effect. The results show the classification of RE solutions into 2 classes: Class I contains the REs with low magnetic moment, whereas Class II includes the REs of high magnetic moment. Only the latter group shows the enrichment of ions in the vicinity of the magnet which encourages the implementation of magnetic separation into existing hydrometallurgical technology to enhance the selectivity of REE.

关键词： magnetic separation Paramagnetic rare earth ions Enrichment Halbach array Interferometry Aqueous solution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

magnetic separation studies on ferruginous chromite fine to enhance Cr:Fe ratio

引用

International Journal of Minerals,Metallurgy and Materials 2015年第3期22卷 217-224页

作者： Sunil Kumar Tripathy P.K.Banerjee Nikkam Suresh Research and Development Division Tata Steel Ltd. Fuel and Mineral Engineering Dept. Indian School of Mines

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.

关键词： chromite ore treatment magnetic separation characterizafion mineral processing industry

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Development of the magnetic separation device for surface cracks of delinted cottonseed

引用

International Journal of Agricultural and Biological Engineering 2023年第6期16卷 11-19页

作者： Xinwu Du Guodong Wang Jing Pang Pengfei Li Xin Jin Wenhua Mao College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471003HenanChina Longmen Laboratory Luoyang 471000HenanChina Institute of Mechatronics Technology and Application Chinese Academy of Agricultural Mechanization SciencesBeijing 100080China

In seed processing for commercial production,the collision or friction between mechanical parts and seed is inevitable.These collisions or friction can cause cracks on the surface of the seed,which can affect germination rates and ultimately reduce crop yields.Using the difference of the seed motion trajectories with different crack degrees in the magnetic field,the grading of the surface crack seed can be realized.In this study,the motion law of seed in a non-uniform magnetic field was analyzed by taking the delinted cottonseed as an object.A magnetic separation device for crop seeds was developed.This device was essentially composed of the feed throat,magnetic roller,conveyor belt,and variable-frequency adjustable-speed motor.The magnetic powder adhering seeds enter the magnetic separation device through the feed throat and are conveyed to the magnetic roller through the conveyor belt.The magnetic roller has different adsorption forces on seeds with different degrees of cracking,and seeds fall into different outlets,thus completing the grading of the seeds.By adjusting working parameters such as the magnetic field strength and the speed of the conveyor belt,magnetic separation could be made.In order to verify the grading effect,the magnetic separation accuracy was taken as the inspection index,the magnetic powder’s mesh number,the mass mixing ratio between magnetic powder and delinted cottonseed,and the rotation speed of the magnetic roller were taken as the inspection factors.The response surface methodology was used to optimize the working parameters of the experimental device.The results showed that the optimal process parameters of the magnetic separation device were as follows:the number of magnetic powder meshes was 250,the mass mixing ratio between magnetic powder and delinted cottonseed was 1:20,and when the rotational speed of the magnetic separation roller was 20 r/min,the detection rate reached 92.5%.The designed magnetic separation device can realize the non-destructive batch detection of seed surfa

关键词： magnetic separation delinted cottonseed surface crack response surface design

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare-earth separation based on the differences of ionic magnetic moment via quasi-liquid strategy

引用

Frontiers of Chemical Science and Engineering 2022年第11期16卷 1584-1594页

作者： Na Wang Fujian Li Bangyu Fan Suojiang Zhang Lu Bai Xiangping Zhang College of Chemical and Engineering Zhengzhou UniversityZhengzhou 450001China CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Multiphase Complex SystemsBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process Engineering and Innovation Academy for Green ManufactureChinese Academy of SciencesBeijing 100190China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China College of Chemistry Nanchang UniversityNanchang 330031China

The separation of rare earth elements is particularly difficult due to their similar physicochemical properties.Based on the tiny differences of ionic radius,solvent extraction has been developed as the“mass method”in industry with hundreds of stages,extremely intensive chemical consumption and large capital investments.The differences of the ionic magnetic moment among rare earths are greater than that of ionic radius.Herein,a novel method based on the large ionic magnetic moment differences of rare earth elements was proposed to promote the separation efficiency.Rare earths were firstly dissolved in the ionic liquid,then the ordering degree of them was improved with the Z-bond effect,and finally the magnetic moment differences between paramagnetic and diamagnetic rare earths in quasi-liquid system were enhanced.Taking the separation of Er/Y,Ho/Y and Er/Ho as examples,the results showed that Er(Ⅲ)and Ho(Ⅲ)containing ionic liquids had obvious magnetic response,while ionic liquids containing Y(Ⅲ)had no response.The separation factors of Er/Y and Ho/Y were achieved at 9.0 and 28.82,respectively.magnetic separation via quasi-liquid system strategy provides a possibility of the novel,green,and efficient method for rare earth separation.

关键词： rare earth element different magnetic moment magnetic separation ionic liquid

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Iron-nickel alloy particles with N-doped carbon “armor” as a highly selective and long-lasting catalyst for the synthesis of Nbenzylaniline molecules

引用

Nano Research 2024年第4期17卷 2308-2319页

作者： Gang Wang Longchao Sun Wanyi Liu Haijuan Zhan Shuxian Bi College of Chemistry and Chemical Engineering Ningxia UniversityYinchuan 750021China

A scalable strategy for the convenient and rapid preparation of nitrogen-doped carbon-coated iron-based alloy catalysts was developed.By controlling the type and amount of metal salts in the precursor,various types of nitrogen-doped carbon-coated alloy catalysts can be prepared in a targeted manner.Fe_(2)Ni2@CN materials with small particle sizes and relatively homogeneous basic sites showed promising results in the N-alkylation reaction of benzyl alcohol with aniline(optimum yield:99%).It is worth noting that the catalyst can also be magnetically separated and recovered after the reaction,and its performance can be regenerated through simple calcination.Furthermore,it was confirmed by kinetic experiments that the activation of C–H at the benzyl alcohol benzylic position is the rate-determining step(RDS).According to density flooding theory calculations,Fe_(2)Ni2@CN catalysts require less energy than other materials(Fe@CN and Ni@CN)for the RDS(dehydrogenation reaction)process.Therefore N-alkylation reactions are more easily carried out on Fe_(2)Ni2@CN catalysts,which may be the reason for the best catalytic activity of Fe-Ni alloy materials.These carbon-coated alloy materials will show great potential in more types of heterogeneous catalysis.

关键词： iron-nickel alloy catalyst N-alkylation reaction magnetic separation reaction path dehydrogenation reaction

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Preparation and performance of novel magnetic phase-change-microcapsule-supported Bi_(2)WO_(6)catalyst

引用

Chinese Chemical Letters 2024年第3期35卷 158-161页

作者： Zhuoni Jiang Zhiqing Ge Shuo Yan Jingjing Shu Mozhen Wang Xuewu Ge Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Southwest University of Science and TechnologyMianyang 621010China

The design and synthesis of novel photocatalyst with self-temperature control function is an important topic in the field of advanced environmental functional materials.In this work,submicron-sized magnetic phase change microcapsules composed of paraffin core and Fe_(3)O_(4)-loaded silica shell are prepared,on which the Bi_(2)WO_(6)crystals is grown in situ through hydrothermal reaction to obtain novel magnetic phase-change-microcapsule-supported Bi_(2)WO_(6)catalyst(MP@FS/BWO).The MP@FS/BWO has a paraffin encapsulation ratio of 57.1%,and the phase change enthalpy of 105.1 J/g in a temperature range of 50–60℃,which endows the MP@FS/BWO with a certain self-temperature regulation ability.MP@FS/BWO shows excellent catalytic performance in the decomposition of rhodamine B under the simulated sunlight irradiation.After the light source is turned off,it still has good catalytic ability by maintaining high temperature due to its temperature control function based on the phase transition process.The MP@FS/BWO can be easily recycled by magnetic separation and shows good structural stability and reusability.This work provides a new idea for the development of long-effect and energy-saving outdoor photocatalysts.

关键词： Photocatalyst Phase change microcapsules Self-temperature regulation Bismuth tungstate magnetic separation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Metalizing reduction and magnetic separation of vanadium titano-magnetite based on hot briquetting

引用

International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 225-233页

作者： Shuang-yin Chen Man-sheng Chu School of Materials and Metallurgy Northeastern University

To achieve high efficiency utilization of Panzhihua vanadium titano-magnetite, a new process of metalizing reduction and magnetic separation based on hot briquetting is proposed, and factors that affect the cold strength of the hot-briquetting products and the efficiency of reduction and magnetic separation are successively investigated through laboratory experiments. The relevant mechanisms are elucidated on the basis of microstructural observations. Experimental results show that the optimal process parameters for hot briquetting include a hot briquetting temperature of 475°C, a carbon ratio of 1.2, ore and coal particle sizes of less than 74 μm. Additionally, with respect to metalizing reduction and magnetic separation, the rational parameters include a magnetic field intensity of 50 mT, a reduction temperature of 1350°C, a reduction time of 60 min, and a carbon ratio of 1.2. Under these above conditions, the crushing strength of the hot-briquetting agglomerates is 1480 N, and the recovery ratios of iron, vanadium, and titanium are as high as 91.19%, 61.82%, and 85.31%, respectively. The new process of metalizing reduction and magnetic separation based on hot briquetting demonstrates the evident technological advantages of high efficiency separation of iron from other valuable elements in the vanadium titano-magnetite.

关键词： magnetite hot briquetting ore reduction magnetic separation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Modeling assessment of recovering iron from red mud by direct reduction： magnetic separation based on response surface methodology

引用

Journal of Iron and Steel Research(International) 2018年第5期25卷 497-505页

作者： Ran Wang Zheng-gen Liu Man-sheng Chu Hong-tao Wang Wei Zhao Li-hua Gao School of Metallurgy Northeastern UniversityShenyang 110819 Liaoning China Northeastern Institute of Metal Materials Co. LtdShenyang 110108 Liaoning China

Red mud, the waste generated during alumina production, contains iron and other valuable metals. To recover the iron efficiently from red mud, a three-factor five-level central composite design in response surface methodology was used to study the effects of process parameters, such as FC/O （the molar ratio of fixed carbon in coal to reducible oxygen of iron oxide in red mud）, reduction temperature, reduction time, and their interaction on the iron recovery rate and total iron content in magnetic product obtained from the process of direct reduction-magnetic separation. The relevant assessment model was established. The model could predict the changing rules of iron recovery rate and total iron content in the magnetic product affected by the process parameters. The results show that the iron recovery rate is significantly influenced by three factors and reduction temperature plays the most important role. The iron recovery rate and total iron content in magnetic product could be up to 98.37 and 82.52%, respectively, under the numerically optimal process parameters condition of reduction temperature of 1400 ℃, FC/O of 0.80 and reduction time of 100 min obtained by the assessment model. The predicted values are in good agreement with the experimental values.

关键词： Red mud - Iron recovery Direct reduction magnetic separation Response surface methodology

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：