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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 335-350页

作者： Michal Kucewicz Pawel Baranowski Jerzy Maachowski Faculty of Mechanical Engineering Institute of Mechanics and Computational EngineeringMilitary University of Technology2 Gen.S.Kaliskiego StreetWarsaw00-908Poland

In this paper,the Johnson-Holmquist concrete(JHC)constitutive model is adopted for modeling and simulating the fracture of dolomite.A detailed step-by-step procedure for determining all required parameters,based on a series of experiments under quasi-static and dynamic regimes,is *** rate coefficients,failure surfaces,equations of state and damage/failure constants are acquired based on the experimental data and finite element *** JHC model with the obtained parameters for dolomite is subsequently validated using quasi-static uniaxial and triaxial compression tests as well as dynamic split Hopkinson pressure bar(SHPB)*** influence of mesh size is also *** shows that the simulated fracture behavior and waveform data are in good agreement with the experimental data for all tests under both quasi-static and dynamic loading *** studies will implement the validated JHC model in small-and large-scale blasting simulations.

关键词： Johnson-Holmquist concrete(JHC)model Rock modeling dolomite Constitutive modeling Split Hopkinson pressure bar(SHPB) Fracture Triaxial compression

dolomite apatite separation by amphoteric collector in presence of bacteria

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Journal of Central South University 2013年第6期20卷 1645-1652页

作者： Elmahdy Ahmed El-Mofty Salah Abdel-Khalek Mohamed Abdel-Khalek Nagui El-MidanyAyman Central Metallurgical Research and Development Institute Mining Petroleum and Metallurgical Engineering DepartmentCairo University

Bioflotation represents one of the growing trends to enhance the selectivity of conventional flotation processes. It utilizes the micro-organisms to replace or to interact with the chemical reagents to increase the gap between surface properties of similar minerals and to enhance the separation selectivity. In this work, dolomite-phosphate separation was investigated using amphoteric collector （dodecyl-N-carboxyethyl-N-hyroxyethyl-imidazoline） in presence of bacteria. Two types of bacteria, Corynebacterium- diphtheriae-intermedius （CDI）, and Pseudomonas aeruginosa （PA）, were used. The collector-bacteria interaction was characterized by Fourier transform infra-red （FTIR）, frothing height and Zeta potential. The results show that the collector-bacteria interaction improves the flotation selectivity. Although, the PA positively affects the separation results, the CDI cannot lower the MgO to less than 1%. A phosphate content of 0.7% MgO and 31.77% P205 with a recovery of 68% at pH 11, 3.0 kg/t amphoteric collector, 4× 10^7 cells of PA is obtained.

关键词： dolomite phosphate amphoteric collector bacteria bio-flotation carbonate minerals

Effect of depressants on flotation separation of magnesite from dolomite and calcite

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International Journal of Mining Science and Technology 2023年第1期33卷 83-91页

作者： Wenqing Qin Junjie Hu Hailing Zhu Fen Jiao Wenhao Jia Junwei Han Chen Chen School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China

The flotation separation of magnesite from calcium-containing minerals has always been a difficult subject in minerals *** work studied the inhibition effects of carboxymethyl cellulose(CMC),sodium lignosulphonate,polyaspartic acid(PASP)and sodium silicate on flotation behaviors of magnesite,dolomite and calcite,providing guidance for the development of reagents in magnesite *** micro-flotation results showed that among these four depressants,sodium silicate presented the strongest selectivity due to the highest recovery difference,and the flotation separation of magnesite from dolomite and calcite could be achieved by using sodium silicate as the *** angle measurement indicated that the addition of sodium silicate caused the largest differences in surface wettability of the three minerals,which was in line with micro-flotation ***,zeta potential test,the Fourier transform infrared(FT-IR)spectroscopy and atomic force microscope(AFM)imaging were used to reveal the inhibition mechanism of sodium *** results indicated that the dominated component SiO(OH)3of sodium silicate could adsorb on minerals surfaces,and the adsorption of sodium silicate hardly affected the adsorption of NaOL on magnesite surface,but caused the reduction of NaOL adsorption on dolomite and calcite surfaces,thereby increasing the flotation selectivity.

关键词： Sodium silicate Magnesite dolomite Calcite Flotation separation Inhibition

Flotation behavior and electronic simulations of rare earth minerals in the presence of dolomite supernatant using sodium oleate collector

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Journal of Rare Earths 2019年第1期37卷 101-112,M0005页

作者： E.R.L.Espiritu G.R.da Silva D.Azizi F.Larachi K.E.Waters Department of Mining and Materials Engineering McGill University Department of Chemical Engineering Université Laval

Common rare earth(RE) minerals, such as bastnasite and monazite, may be formed in deposits associated with carbonate gangue, such as calcite and dolomite. Sodium oleate is a widely used collector for the flotation of both RE and gangue minerals, which might, therefore, be an inefficient process due to the lack of selectivity of this collector. Since these minerals are also sparingly soluble in solution, they could release their constituent ions into the solution, which could affect the floatability of other minerals. In this study, the interactions of sodium oleate with bastnasite and monazite in the presence of dissolved dolomite species have been investigated. Microflotation tests were carried out to explore the effects of these dissolved species on the floatability of the RE minerals. Zeta potential measurements and XPS characterization were carried out to understand how the species affect the collector adsorption. To complement these characterizations, density functional theory(DFT) simulations were conducted to investigate the collector-mineral and collector-adsorbed species(on the mineral surface) *** results show that collector-dolomite interaction energy is greater than that of collector-adsorbed species, but lower than collector-monazite interaction energy, explaining the decrease in the minerals' recovery upon exposure to the dissolved mineral species. It is also shown that oleate ions(OI^-) have the strongest interaction with the minerals compared to other oleate species such as acid soap(HOI_2^-) and oleate dimer(OI_2^(2-)). The behavior(strength and selectivity) of sodium oleate towards RE minerals and dolomite, as compared to other RE mineral collectors(such as aromatic hydroxamate), is attributed mainly to the collector's and the minerals' structure. The long hydrocarbon chain of sodium oleate which imparts hydrophobic characteristic to the minerals, makes it stronger collector than ***, sodium oleate(with linear str

关键词： Rare earth minerals Bastnsite Monazite dolomite Sodium oleate DFT simulation

Production of high-purity Mg metal from dolomite through novel molten salt electrolysis and vacuum distillation

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Journal of Magnesium and Alloys 2023年第4期11卷 1308-1320页

作者： Hyeong-Jun Jeoung Tae-Hyuk Lee Jin-Young Lee Kyung-Woo Yi Jungshin Kang Korea Institute of Geoscience and Mineral Resources 124 Gwahak-ro Yuseong-guDaejeon 34132Republic of Korea Department of Materials Science and Engineering Seoul National University1 Gwanak-roGwanak-guSeoul 08826Republic of Korea Department of Resources Engineering University of Science and Technology217 Gajeong-ro Yuseong-guDaejeon 34113Republic of Korea School of Materials Science and Engineering Pusan National University2 Busandaehak-roGeumjeong-guBusan 46241Republic of Korea

In this study,a novel Mg production process for producing high-purity Mg metal from dolomite was *** the electrolysis of calcined dolomite was conducted using Cu cathode and C anode in MgF_(2)–LiF molten salt at 1083–1173 K by applying an average current of 1.42–1.46 A for 9.50–21.0 h,the current efficiency of 66.4–88.6%was *** produced Mg alloys consisted of MgCu_(2)and Cu(Mg)or MgCu_(2)and CuMg_(2)phases,depending on the Mg concentration in the Mg *** the electrolysis of calcined dolomite was conducted in MgF_(2)–LiF–CaF_(2)molten salt at 1083 K,the current efficiency was 40.9–71.4%,owing to undesired reactions such as electroreduction of Ca^(2+)or/and CO_(3)^(2−)***,the current efficiency increased from 40.9%to 63.2%by utilizing a Pt anode,because the occurrence of CO_(3)^(2−)ions in the molten salt was *** vacuum distillation of the obtained Mg alloys at 1300 K for 10 h,Mg metal with a purity of 99.9996–99.9998%was ***,the feasibility of this novel process for the production of high-purity Mg metal from dolomite was demonstrated.

关键词： High-purity magnesium dolomite Magnesium oxide Electrolytic process Copper metal cathode Vacuum distillation

Effect and mechanism of dolomite with different size fractions on hematite flotation using sodium oleate as collector

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Journal of Central South University 2016年第3期23卷 529-534页

作者：罗溪梅印万忠王云帆孙传尧马英强刘建 State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization(Faculty of Land and Rescource Engineering Kunming University of Science and Technology)Kunming 650093China College of Zijin Mining Fuzhou UniversityFuzhou 350116China Faculty of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Beijing General Research Institute of Mining&Metallurgy Beijing 100044China

The effect of dolomite with different particle size fractions on hematite flotation was studied using sodium oleate as collector at p H of about 9. The effect mechanism of dolomite on hematite flotation was investigated by means of solution chemistry, ultraviolet spectrophotometry(UV), inductively coupled plasma atomic emission spectrometry(ICP-AES) and X-ray photoelectron spectroscopy(XPS). It is observed that dolomite with different size fractions has depressing effect on hematite flotation using sodium oleate as collector, and dolomite could be the "mineral depressant" of hematite using sodium oleate as collector. The reasons for that are concerned with sodium oleate consumption and the adsorption onto hematite of dissolved species of dolomite.

关键词： dolomite hematite sodium oleate mineral dissolution depressing effect

Mechanism of calcium lignosulfonate in apatite and dolomite flotation system

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1697-1704页

作者： Bo Feng Liangzhu Zhang Wenpu Zhang Huihui Wang Zhiyong Gao Jiangxi Key Laboratory of Mining Engineering Jiangxi University of Science and TechnologyGanzhou 341000China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China State Key Laboratory of Rare Metals Separation and Comprehensive Utilization Guangzhou 510600China

Since the physical and chemical properties of apatite and dolomite can be similar,the separation of these two minerals is ***,when performing this separation using the flotation method,it is necessary to search for selective *** experimental research was performed on the separation behavior of apatite and dolomite using calcium lignosulfonate as a depressant,and the mechanism by which this occurs was *** results show that calcium lignosulfonate has a depressant effect on both apatite and dolomite,but the depressant effect on dolomite is stronger at the same *** analysis shows that the adsorptive capacity of calcium lignosulfonate on dolomite is higher than that of apatite,which is due to the strong reaction between calcium lignosulfonate and the Ca sites on *** addition,there is a hydrogen bond between calcium lignosulfonate and dolomite,which further prevents the adsorption of sodium oleate to dolomite,thus greatly inhibiting the flotation of dolomite.

关键词： apatite dolomite calcium lignosulfonate depression mechanism

Synthesis of glass ceramics from kaolin and dolomite mixture

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 194-201页

作者： Mohamed Reda Boudchicha Fausto Rubio Slimane Achour Engineering Mechanics and Materials Laboratory Mechanical Engineering Department Faculty of Technology Universite 20 Aout 1955 de Skikda Skikda 21000 Algeria Ceramics and Glass Institute Consejo Superior de Investigaciones Cientificas Madrid 28049 Spain National Polytechnic School Constantine 25000 Algeria

Cordierite- and anorthite-based binary glass ceramics of the CaO-MgO-Al2O3-SiO2 （CMAS） system were synthesized by mixing local and abundant raw minerals （kaolin and doloma by mass ratio of 82/18）. A kinetics study reveals that the activation energy of crystalli- zation （Ea） calculated by the methods of Kissinger and Marotta are 438 kJ·mol^-1 and 459 kJ·mol^-1, respectively. The Avrami parameter （n） is estimated to be approximately equal to 1, corresponding to the surface crystallization mechanism. X-ray diffraction （XRD） analysis shows that the anorthite and cordierite crystals are precipitated from the parent glass as major phases. Anorthite crystals first form at 850℃, whereas the μ-cordierite phase appears after heat treatment at 950℃. Thereafter, the cordierite allotropically transforms to α-cordierite at 1000℃. Complete densification is achieved at 950℃; however, the density slightly decreases at higher temperatures, reaching a stable value of 2.63 kg·m^-3 between 1000℃ and 1100℃, The highest Vickers hardness of 6 GPa is also obtained at 950℃. However, a substantial decrease in hardness is recorded at 1000℃; at higher sintering temperatures, it slightly increases with increasing temperature as the ct-cordierite crystallizes.

关键词： glass ceramics kaolinite dolomite crystallization activation energy

Effective utilization of dolomitic lead-zinc waste rock by replacing dolomite as flux in iron ore sintering process

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Journal of Iron and Steel Research International 2024年第8期31卷 1861-1872页

作者： Xin Wang Cong-cong Yang Jian Pan De-qing Zhu Zheng-qi Guo Guang-hui Xia Shi-juan Qu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Low-Carbon and Hydrogen Metallurgy Research Center Central South UniversityChangsha 410083HunanChina

With increasingly stringent environmental protection policies,cost-effective and value-added treatment of massive lead-zinc waste rock(LZWR)generated from the preconcentration process has attracted substantial attention.A type of dolomitic LZWR with 18 wt.%MgO,27 wt.%CaO,0.29 wt.%Zn and 1.43 wt.%S was used as a replacement flux in the iron ore sintering *** sinter pot tests were carried out based on an industrial ore *** results show that replacing 0%-60%of dolomite with LZWR does not adversely affect the sintering productivity,fuel consumption rate,and the quality of the sinter products,while the Zn and S elements contained in LZWR can be effectively removed with the residual Zn and S contents of the resultant sinter products being less than 0.02 and 0.055 wt.%,***,substituting LZWR for dolomite as a flux inevitably increases the SO_(2) concentration in the sintering flue gas due to its high sulfur *** the processing capacity of the sintering flue gas desulfurization system,the replacement ratio of dolomite can reach 40%,equal to LZWR consumption of 24.3 kg per ton of *** SO_(2) in sintering flue gas can be recovered to produce(NH_(4))_(2)SO_(4) or HSO_(4),while the volatilized Zn collected into the zinc-containing dust can be subsequently recycled by the rotary hearth furnace ***,it is technologically and economically feasible to use the LZWR as a replacement flux in the iron ore sintering process,providing a new way for the safe,large-scale and low-cost treatment of LZWR.

关键词： Lead Zinc waste rock dolomite Sintering Flue gas Sinter product

Rock physical characteristics of deep dolomite under complex geological conditions:A case study of 4th Member of Sinian Dengying Formation in the Sichuan Basin,China

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Petroleum Science 2024年第4期21卷 2370-2382页

作者： Chuang Li Shu-Xin Pan Hong-Bin Wang Ji-Xin Deng Jian-Guo Zhao Zhi Li Yu Zhang Northwest Branch of Research Institute of Petroleum Exploration&Development Lanzhou730020GansuChina State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Department of Geophysics and Exploration College of GeophysicsChengdu University of TechnologyChengdu610059SichuanChina

The deep-ultra deep carbonate reservoir in China,commonly subjected to modification of multi-stage diagenesis,has extremely high *** rock physics analysis cannot accurately identify the elastic responses of ***,the rock physics properties of the dolomite from the 4th Member of the Sinian Dengying Formation are experimentally measured,and the change law of rock physics characteristics is investigated within the framework of the diagenetic processes by the analysis of the elastic and petrologic characteristics,pore structure,and sedimentary *** results show that the differentiated diagenesis results in different pore structure characteristics and microtexture characteristics of the *** microbial dolomite of the algal mound-grain beach facies is subjected to the contemporaneous microbial dolomitization and seepage-reflux dolomitization,penecontemporaneous selective dissolution,burial dolomitization,and hydrothermal *** resultant crystalline dolomite is found with one main type of the dolomite crystal contact boundaries,and the dissolution pore is extensive *** siliceous,muddy,and limy dolomite of the interbeach sea environment mainly experiences the weak capillary concentration dolomitization,intensive mechanical compaction-induced densification,and burial *** crystalline dolomite is observed with four types of contact boundaries,namely the dolomite contact,clay contact,quartz contact,and calcite contact boundaries,and porosity mostly attributed to residual primary inter-granular or crystalline *** samples with the same crystal boundary condition have consistent correlations between the compressional-and shear-wave velocities,and between the compressional-wave velocity and the velocity ***,the variation of the acoustic velocity with effective pressure and the intensity of pore-scale fluid-related dispersion are controlled by the differentiation of pore st

关键词： Deep-ultra deep carbonate reservoirs Rock physics properties dolomite Seismic elastic properties Micro-crack Pore structure types