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International Journal of Modeling, simulation, and scientific Computing 2017年第1期8卷 271-296页

作者： M.Yaghobi Moghaddam s.z.shafaei tonkaboni M.Noaparast F.Doulati Ardejani school of Mining College of Engineering University of TehranP.O.Box 14395-515TehranIran

This paper attempts to address some nonlinear differential equations which describe main mechanisms governing heap(bio)leaching process as an important metallurgical facility in mining and mineral processing *** Homotopy Perturbation Method(HPM),Finite Volume Method and Analytical(Laplace)Method have been employed to provide proper solutions for these *** was made between the methods and agreement was close;considering the fact that the proposed solution in comparison with the others provided a remarkable accuracy in dealing with nonlinear problems associated with mining and mineral processing *** maximum error of HPM in relation to the analytical solution was *** numerical finite volume method incorporating a computational fluid dynamics model termed PHOENICs provided rational and accurate results;describing that many chemical and biological processes extremely affect the transportation mechanism of the aqueous compounds in a heap structure and subsequently on the process ***,all solution methods presented to simulate heap leaching process provided valuable information related to the time dependence concentrations of dissolved *** results obtained from this study can be effectively applied to manage the heap leaching costs to make the process feasible.

关键词： Diffusion-advection-reaction equations nonlinear problems Homotopy perturbation method finite volume method analytical solution Heap(bio)-leaching

Dual effects of sodium sulfide on the flotation behavior of chalcopyrite:Ⅰ. Effect of pulp potential

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 415-422页

作者： Bijan Taheri Mahmoud Abdollahy sied ziaedin shafaei tonkaboni soheyla Javadian Mohammadreza Yarahmadi Mining Division Tarbiat Modares University Faculty of Mining Engineering University of Tehran Faculty of science Tarbiat Modares University Research and Development Division of sarcheshmeh Copper Complex

This study explores the flotation behavior of chalcopyrite in the presence of different concentrations of sodium sulfide （Na2s·9H2O） at pH 12 under controlled potential conditions. It was observed that the flotation of chalcopyrite is not depressed completely when the pulp potential is low, even at high concentrations of sodium sulfide, i.e., 10-1-10-2 mol/L. However, a partial and controlled oxidation of pulp does enhance the effectiveness of sodium sulfide on the depression of chalcopyrite. Characterization of the chalcopyrite particle surface by X-ray photoelectron spectroscopy allowed the identification of hydrophilic and hydrophobic surface species, which are responsible for the depression and flotation of chalcopyrite. Changes in pulp potential were found to be an effective float controlling parameter, by which Na2s can be used to initiate or depress the flotation behavior of chalcopyrite.

关键词： chalcopyrite flotation electric potential sodium sulfide

Bio-dissolution of Cu,Mo and Re from molybdenite concentrate using mix mesophilic microorganism in shake flask

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Transactions of Nonferrous Metals society of China 2013年第1期23卷 219-230页

作者： H.ABDOLLAHI s.z.shafaei M.N OAPARAsT z.MANAFI N.AsLAN school of Mining College of EngineeringUniversity of TehranTehranIran National Iranian Copper Industries Co.sarcheshmeh Mine Iran Mining Engineering Department Cum huriyet UniversitySivasTurkey

The application of the response surface methodology and the central composite design（CCD） technique for modeling and optimization of the influence of some operating variables on copper,molybdenum and rhenium recoveries in a bioleaching process was *** main bioleaching parameters,namely pH,solid concentration and inoculum percent,were changed during the bioleaching tests based on *** ranges of the bioleaching process variables used in the design were as follows：pH1.46-2.14,solid concentration 0.95%-11.05%,and inoculum percent 1.59%-18.41%.A total of 20 bioleaching tests were carried out by the CCD method according to software-based designed *** model equations were developed according to the copper,molybdenum and rhenium recoveries obtained with these three *** equations of responses at the base of parameters were achieved by using statistical *** model equations were then individually optimized by using quadratic programming to maximize copper,molybdenum and rhenium recoveries individually within the experimental *** optimum conditions for copper recovery were pH 1.68,solid concentration 0.95% and the inoculum 18.41%（v/v）,while molybdenum and rhenium recoveries were 2.18% and 24.41%,*** predicted values for copper,molybdenum and rhenium recoveries were found to be in good agreement with the experimental *** jarosite formation during bioleaching tests was also investigated.

关键词： bioleaching molybdenite concentrate copper molybdenum rhenium mix mesophilic microorganisms response surface methodology CCD

Bioleaching of sphalerite sample from Kooshk lead-zinc tailing dam

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Transactions of Nonferrous Metals society of China 2013年第12期23卷 3763-3769页

作者： J.V.MEHRABANI s.z.shafaei M.NOAPARAsT s.M.MOUsAVI M.M.RAJAEI school of Mining Engineering College of Engineering University of Tehran Biotechnology Group Chemical Engineering Department Tarbiat Modares University

The zinc extraction from Kooshk lead-zinc tailing dam’s sample was investigated by bioleaching method. The Kooshk lead-zinc deposit/mine is located in Yazd province, Iran, and its tailing dam contains about 3.64%zinc, 0.97%lead and 24.18%iron. Experiments were designed and carried out by a mixed culture of mesophile bacteria as well as a mixed culture of moderate thermophile strain in the shake flasks. The results indicated that, more than 90% of sphalerite was dissolved during 14 d, while without bacteria, 44% of zn was merely extracted. In addition, some experiments were performed in the absence of the bacterial medium （9K）. The results of these experiments indicated significant difference in zn extraction with and without 9K until the 10th day of bioleaching, but after that the zn extraction was improved and the same extraction was achieved at the end of bioleaching tests. This improvement can be attributed to the increase of the number of bacteria or Fe3＋concentration at the last days of leaching. zn extraction kinetics of moderate thermophile bacteria was significantly higher than that of the mesophile, therefore sphalerite was successfully dissolved in preference to the pyrite using moderate thermophile bacteria in a lower redox potential.

关键词： bioleaching pyrite tailing sphalerite

Empirical model for bio-extraction of copper from low grade ore using response surface methodology

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Transactions of Nonferrous Metals society of China 2015年第12期25卷 4126-4143页

作者： M.YAGHOBI MOGHADDAM s.z.shafaei M.NOAPARAsT F.DOULATI ARDEJANI H.ABDOLLAHI M.RANJBAR M.sCHAFFIE z.MANAFI school of Mining College of Engineering University of Tehran Department of Mining Engineering Shahid Bahonar University of Kerman Department of Chemical Engineering Shahid Bahonar University of Kerman Hydrometallurgy Research Unit R&D Center Sarcheshmeh Copper Mine Complex

The copper extraction in shaking bioreactors was modeled and optimized using response surface methodology（RsM）. Influential parameters in the mesophilic bioleaching process of a low-grade copper ore including p H value, pulp density, and initial concentration of ferrous ions were comprehensively studied. The effect of leaching time on the response（copper extraction） at the 1st, 4th, 9th, 14 th and 22 nd days of treatment was modeled and examined. The central composite design methodology（CCD） was used as the design matrix to predict the optimal level of these parameters. Then, the model equation at the 22 nd day was optimized using the quadratic programming（QP） to maximize the total copper extraction within the studied experimental range. Under the optimal condition（initial p H value of 2.0, pulp density of 1.59%, and initial concentration of ferrous ions of 0 g/L）, the total copper extraction predicted by the model is 85.98% which is significantly close to that obtained from the experiment（84.57%）. The results show that RsM could be useful to predict the maximum copper extraction from a low-grade ore and investigate the effects of variables on the final response. Besides, a couple of statistically significant interactions are derived between p H value and pulp density as well as p H value and initial ferrous ion concentration which are precisely interpreted. However, there is no statistically significant interaction between the initial ferrous ion concentration and the pulp density. Additionally, the response at optimal levels of p H value and pulp density is found to be independent on the level of initial ferrous concentration.

关键词： modeling optimization bacterial leaching response surface methodology copper extraction copper ore

Modeling and process optimization for microbial desulfurization of coal by using a two-level full factorial design

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International Journal of Mining science and Technology 2013年第2期23卷 266-270页

作者： Golshani T. Jorjani E. Chelgani s. Chehreh shafaei s.z. Nafechi Y. Heidari Department of Mining Engineering Science and Research Branch Islamic Azad University Young Researchers and Elites club Science and Research Branch Islamic Azad University school of Mining Engineering University of Tehran

The microbial sulfur removal was investigated on high sulfur content (1.9%) coal concentrate from Tabas coal preparation plant. A mixed culture of ferrooxidans microorganisms was isolated from the tailing dam of the plant. Full factorial method was used to design laboratory test and to evaluate the effects of pH, particle size, iron sulfate concentration, pulp density, and bioleaching time on sulfur reduction. statistical analyses of experimental data were considered and showed increases of pH and particle size had negative effects on sulfur reduction, whereas increases of pulp density and bioleaching time raised microbial desulfurization rate. According to results of designing, and regarding statistical factors, the optimum values for maximum sulfur reduction were obtained; pH (1.5), particle size (-180 μm), iron sulfate concentration (2.7 mmol/L), pulp density (10%) and bioleaching time (14 d), which leaded to 51.5% reduction from the total sulfur of sample.

关键词： Coal Microbial desulfurization Ferrooxidant microorganisms statistical technique