The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Merete Tangstad - One of the best experts on this subject based on the ideXlab platform.
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New advances in metallurgical solar Grade Silicon based on recent Norwegian research activities
Physica Status Solidi (c), 2012Co-Authors: Eivind Øvrelid, Merete Tangstad, Gabriella Tranell, Otto Lohne, Bruno CeccaroliAbstract:Among the new routes for the production of solar Grade Silicon, the metallurgical refining leading to upGraded metallurgical Grade (UMG) Silicon emerge as serious alternatives to replace the feedstock produced by the Siemens process (commonly called polySilicon). Most of these new alternative processes generally consist of a sequence of purification steps. The most effective and frequently used among these refining steps will be described. Some recent results based on research studies carried out in Norway will be presented with more details. The intention is to give an overview and an understanding of these emerging processes and provide some tools to optimize and further develop new cost efficient processes for production of solar Grade Silicon (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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Processes for Upgrading Metallurgical Grade Silicon to Solar Grade Silicon
Energy Procedia, 2012Co-Authors: Jafar Safarian, Gabriella Tranell, Merete TangstadAbstract:The photovoltaic (PV) industry is in rapid growth and a large supply of PV feedstock materials must be provided to maintain this growth. Since Silicon is still the dominant material for the fabrication of solar cells, low-cost solar-Grade Silicon (SoG-Si) feedstock is demanded. The most cost-effective and direct approach for producing SoG-Si is to purify and upGrade metallurgical-Grade Silicon. Many impurities in MG-Si can be effectively removed through directional solidification of molten Silicon. However, the removal of boron (B) and phosphorus (P) by this method is difficult and expensive due to the relatively large distribution coefficients of these elements. Therefore, the elimination of B and P to the levels required for SoG-Si feedstock requires the development of new processes. In the present study, the effect of impurities on the solar cell efficiencies and the impurity contents in Silicon materials are studied. The chemical and metallurgical processes that can be applied to purify metallurgical Grade Silicon to solar Grade Silicon are reviewed and evaluated. It is shown that under development Silicon refining processes are applicable to produce solar Grade Silicon. However, there are specific challenges for each process and their benefits and risks must be considered for economic production.
Sergey M. Karabanov - One of the best experts on this subject based on the ideXlab platform.
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Study of Plasma-chemical Purification of Metallurgical-Grade Silicon under the Conditions of Electromagnetic Stirring by Mathematical Modeling
Energy Procedia, 2018Co-Authors: Sergey M. Karabanov, Dmitriy V. Suvorov, Evgeniy V. Slivkin, Andrey S. Karabanov, Dmitriy Yu. Tarabrin, Oleg A. Belyakov, Andrey E. Serebryakov, Vladimir V. KlimakovAbstract:Abstract In this paper, we present the research results of plasma-chemical purification of metallurgical-Grade Silicon from boron and carbon under the conditions of electromagnetic stirring of Silicon melt. The research is carried out by mathematical modeling using COMSOL Multiphysics software. The regularities between the process parameters and the efficiency of Silicon purification from boron and carbon are established. The obtained data show that Silicon plasma-chemical purification using electromagnetic stirring allows achievement of a purity level corresponding to the solar-Grade Silicon requirements.
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New Environmentally Friendly Chlorine-Free Solar-Grade Silicon Production Technologies
Mediterranean Green Buildings & Renewable Energy, 2016Co-Authors: Sergey M. Karabanov, Victor I. Yasevich, Dmitriy V. Suvorov, Evgeniy V. Slivkin, Andrey S. KarabanovAbstract:One of the major lines of solar energy development is the creation of environmentally friendly, wasteless, and cheap solar-Grade Silicon production technologies. Currently the main Silicon production technologies are based on a reduction of Silicon hydrogen chloride compounds: trichlorosilane, tetrachlorosilane, and monosilane. These technologies use environmentally dangerous and nonfireproof compounds in quantity. Such production levels can be profitable only in large volumes (more than 1000 tons per year). This chapter examines the research results of methods of Silicon purification by extraction from a solid phase and plasma-chemical purification of metallurgical-Grade Silicon from impurities to the solar-Grade level.
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Mathematical modeling and experimental research of the method of plasma chemical purification of metallurgical-Grade Silicon
2016 IEEE 16th International Conference on Environment and Electrical Engineering (EEEIC), 2016Co-Authors: Sergey M. Karabanov, Victor I. Yasevich, Dmitriy V. Suvorov, Andrey S. KarabanovAbstract:One of the major lines of solar energy development is the creation of environmentally friendly, wasteless and cheap solar-Grade Silicon production technology. Currently the main Silicon production technologies are based on reduction of Silicon hydrogen chloride compounds: trichlorosilane, tetrachlorosilane, monosilane. These technologies use harmful and potentially dangerous compounds in quantity. These productions can be profitable only at big volumes (more than 1000 tons per year). The paper presents the research results of mathematical modeling and experimental research of metallurgical-Grade Silicon purification by the method of plasma chemical treatment of Silicon melt up to solar-Grade level with further direct crystallization in one reactor.
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New Technologies for Solar Grade Silicon Production
MRS Proceedings, 2002Co-Authors: Sergey M. KarabanovAbstract:AbstractThe paper presents the results of study of carbothermic reduction method for solar Grade Silicon (SG-Si) production. The interconnection between the purity of source materials and derivable Silicon has been established. The technological concept of SG-Si production, including source materials preparation, carbothermic process, Silicon filtration and crystallization is suggested. The comparative analysis data of different methods of SG-Si is given.
Xuetao Luo - One of the best experts on this subject based on the ideXlab platform.
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reaction mechanism and kinetics of boron removal from metallurgical Grade Silicon based on li2o sio2 slags
JOM, 2016Co-Authors: Huixian Lai, Ming Fang, Liuqing Huang, Pengfei Xing, Xuetao LuoAbstract:Boron removal from metallurgical-Grade Silicon by Li2O-SiO2 slag refining under an air atmosphere was experimentally investigated to explore the potential of this method for achieving high boron removal. The boron concentration in the refined Silicon was studied under different conditions of holding time, slag composition, and mass ratio of slag to Silicon. The boron concentration in metallurgical-Grade Silicon was successfully reduced from 8.6 ppmw to 0.4 ppmw after slag refining for 0.5 h at 1973 K when the mass ratio of the 60 wt.% Li2O-40 wt.% SiO2 slag to metallurgical-Grade Silicon was 3. It was proposed that the addition of CaF2 decreased the activity of silica, which brings about a negative effect on the boron removal capacity of Li2O-SiO2 slags. Moreover, the reaction mechanism and kinetics of boron removal were further studied. Analysis of the boron concentration in the resulting slag after refining revealed that the primary boron removal approach was that a large amount of boron was oxidized and then volatilized to the atmosphere in the form of gaseous borates. Based on the two-film theory, the total mass transfer coefficient of boron was determined to be 2.3 × 10−2 μm/s.
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evaporation behavior of phosphorus from metallurgical Grade Silicon via calcium based slag treatment and hydrochloric acid leaching
Journal of Electronic Materials, 2016Co-Authors: Liuqing Huang, Ming Fang, Huixian Lai, Pengfei Xing, Xuetao LuoAbstract:Phosphorus removal from metallurgical Grade Silicon by CaO-SiO2-CaCl2 slag treatment, HCl leaching, and vacuum refining was investigated. The effect of different compositions of slag was evaluated. The calcium concentration in slag-treated Silicon increased with increasing CaO/SiO2 mass ratio of slag, decreasing the evaporation efficiency of phosphorus in molten Silicon. The total phosphorus removal efficiency changed from 93.0% to 98.3% when the slag-treated Silicon was treated with HCl before vacuum refining. The final concentration of phosphorus in Silicon was 0.43 ppmw. This is because phosphorus was removed from metallurgical-Grade Silicon as follows: Phosphorus reacts with slag at the Silicon/slag interface and forms Ca3(PO4)2 and Ca3P2, most of which diffuse from the interface to the slag phase. The remaining Ca3(PO4)2 and Ca3P2 reduce the phosphorus removal efficiency by altering the activity coefficient of phosphorus in molten Silicon. HCl leaching enhanced the phosphorus removal efficiency by removing the remaining Ca3(PO4)2 and Ca3P2. Therefore, the mass transfer of phosphorus from metallurgical-Grade Silicon was accelerated.
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effect of calcium based slag treatment on hydrometallurgical purification of metallurgical Grade Silicon
Industrial & Engineering Chemistry Research, 2014Co-Authors: Ming Fang, Liuqing Huang, Huixian Lai, Juan Chen, Pengfei Xing, Xuetao LuoAbstract:The effect of CaO–SiO2–CaF2 slag treatment on acid leaching of metallurgical-Grade Silicon was investigated in this study. Based on the analysis of the acid sensitivity of silicide precipitated phases, it was found that HCl + HF mixed acid was a better solvent to remove Si–Fe system intermetallics from metallurgical-Grade Silicon, and HCl was an effective leaching agent for eliminating Si–Ca system intermetallics from slag treated metallurgical-Grade Silicon. Acid leaching experimental results revealed that slag treatment enhanced the extraction of impurities Fe, Al, Mn, and Ti from metallurgical-Grade Silicon compared with results in the absence of slag treatment. Moreover, a remarkable decrease in the concentration of impurities B and P was attributed to the oxidation reaction in the slag refining process.
Malek Ould Hamou - One of the best experts on this subject based on the ideXlab platform.
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Recovery of solar Grade Silicon from kerf loss slurry waste
Renewable and Sustainable Energy Reviews, 2014Co-Authors: Nadjib Drouiche, Patricia Cuellar, Fouad Kerkar, Sidali Medjahed, Nabila Boutouchent-guerfi, Malek Ould HamouAbstract:Abstract During the last two decades and, particularly, in recent years, the photovoltaic sector has increased interest in the recovery of solar Grade Silicon (SOG). In order to further develop related technologies and to find suitable commercial applications for its recovery, it is essential to understand the current scientific know-how and advances. This review paper copes with recently published scientific articles in which the recovery of solar Grade Silicon has been studied. In addition, the present work provides an updated picture of the current understanding of the theory behind the employed technologies. The techniques discussed were divided into six categories, which are: (i) alloying process, (ii) hydrobromination, (iii) supercritical water, (iv) electrophoresis and gravitational settling, (v) directional solidification, and (vi) centrifugation.
Ming Fang - One of the best experts on this subject based on the ideXlab platform.
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reaction mechanism and kinetics of boron removal from metallurgical Grade Silicon based on li2o sio2 slags
JOM, 2016Co-Authors: Huixian Lai, Ming Fang, Liuqing Huang, Pengfei Xing, Xuetao LuoAbstract:Boron removal from metallurgical-Grade Silicon by Li2O-SiO2 slag refining under an air atmosphere was experimentally investigated to explore the potential of this method for achieving high boron removal. The boron concentration in the refined Silicon was studied under different conditions of holding time, slag composition, and mass ratio of slag to Silicon. The boron concentration in metallurgical-Grade Silicon was successfully reduced from 8.6 ppmw to 0.4 ppmw after slag refining for 0.5 h at 1973 K when the mass ratio of the 60 wt.% Li2O-40 wt.% SiO2 slag to metallurgical-Grade Silicon was 3. It was proposed that the addition of CaF2 decreased the activity of silica, which brings about a negative effect on the boron removal capacity of Li2O-SiO2 slags. Moreover, the reaction mechanism and kinetics of boron removal were further studied. Analysis of the boron concentration in the resulting slag after refining revealed that the primary boron removal approach was that a large amount of boron was oxidized and then volatilized to the atmosphere in the form of gaseous borates. Based on the two-film theory, the total mass transfer coefficient of boron was determined to be 2.3 × 10−2 μm/s.
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evaporation behavior of phosphorus from metallurgical Grade Silicon via calcium based slag treatment and hydrochloric acid leaching
Journal of Electronic Materials, 2016Co-Authors: Liuqing Huang, Ming Fang, Huixian Lai, Pengfei Xing, Xuetao LuoAbstract:Phosphorus removal from metallurgical Grade Silicon by CaO-SiO2-CaCl2 slag treatment, HCl leaching, and vacuum refining was investigated. The effect of different compositions of slag was evaluated. The calcium concentration in slag-treated Silicon increased with increasing CaO/SiO2 mass ratio of slag, decreasing the evaporation efficiency of phosphorus in molten Silicon. The total phosphorus removal efficiency changed from 93.0% to 98.3% when the slag-treated Silicon was treated with HCl before vacuum refining. The final concentration of phosphorus in Silicon was 0.43 ppmw. This is because phosphorus was removed from metallurgical-Grade Silicon as follows: Phosphorus reacts with slag at the Silicon/slag interface and forms Ca3(PO4)2 and Ca3P2, most of which diffuse from the interface to the slag phase. The remaining Ca3(PO4)2 and Ca3P2 reduce the phosphorus removal efficiency by altering the activity coefficient of phosphorus in molten Silicon. HCl leaching enhanced the phosphorus removal efficiency by removing the remaining Ca3(PO4)2 and Ca3P2. Therefore, the mass transfer of phosphorus from metallurgical-Grade Silicon was accelerated.
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effect of calcium based slag treatment on hydrometallurgical purification of metallurgical Grade Silicon
Industrial & Engineering Chemistry Research, 2014Co-Authors: Ming Fang, Liuqing Huang, Huixian Lai, Juan Chen, Pengfei Xing, Xuetao LuoAbstract:The effect of CaO–SiO2–CaF2 slag treatment on acid leaching of metallurgical-Grade Silicon was investigated in this study. Based on the analysis of the acid sensitivity of silicide precipitated phases, it was found that HCl + HF mixed acid was a better solvent to remove Si–Fe system intermetallics from metallurgical-Grade Silicon, and HCl was an effective leaching agent for eliminating Si–Ca system intermetallics from slag treated metallurgical-Grade Silicon. Acid leaching experimental results revealed that slag treatment enhanced the extraction of impurities Fe, Al, Mn, and Ti from metallurgical-Grade Silicon compared with results in the absence of slag treatment. Moreover, a remarkable decrease in the concentration of impurities B and P was attributed to the oxidation reaction in the slag refining process.
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Effect of sodium-based slag treatment on the distribution of impurities in metallurgical Grade Silicon
Advanced Materials Research, 2013Co-Authors: Ming Fang, Kui Xian Wei, Wen Hui, Liuqing Huang, Huixian Lai, Juan Chen, Zhi Lin Sheng, Jian Ning ShenAbstract:The distribution of impurities in metallurgical Grade Silicon before and after slag treatment was investigated for the purpose of upgrading metallurgical Grade to solar Grade Silicon. It was found that metal impurities co-deposited with Silicon and formed different intermetallics in the precipitated phase, and these intermetallics such as Si-Fe, Si-Ni, Si-Ti-V and Si-Ca-Al-Fe were substituted by Si-Fe-Ti-V after treatment of Na2CO3-SiO2 slag. Non-metallic impurities B and P were nearly homogeneous distribution in metallurgical Grade Silicon before and after slag treatment. Moreover, a particular analysis of the microstructure of slag has been carried out, it was determined that metal impurities Al and Ca could easily migrate from Silicon to slag phase in the refining process.
