Hui-chuan REN , Xiao-bo MIN , Yong KE , Long-gong XIA , Yun-yan WANG , Cong PENG , Yun LI , Rong-he TAN , Chuan-fu ZHANG
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引用次数: 0
Abstract
A method to upgrade the iron grade in copper slag was proposed using lime to decompose Al2O3-containing fayalite melt (AFMT). Thermodynamic calculations indicated that adjusting the CaO/AFMT ratio can yield a residual melt with a FeO concentration of 75-88 wt.% and produce Ca2SiO4. In-situ observations suggested that the reaction was impeded in some way. Quenching experiments revealed that the initial reaction products consisted of calcium ferrite compounds and FeO-CaO melt. At the FeO-CaO melt/AFMT interface, Ca2SiO4 particles precipitated, forming a dense Ca2SiO4 film that significantly impeded mass transfer. Although trace amounts of Al2O3 in AFMT temporarily enhanced mass transfer, they were insufficient to overcome this retardation effect. The decomposition reaction was far from achieving equilibrium, demonstrating a self-retardation effect. Measures must be implemented to eliminate this self-retardation effect and enhance the efficiency of reaction kinetics.
期刊介绍:
The Transactions of Nonferrous Metals Society of China (Trans. Nonferrous Met. Soc. China), founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, INSPEC, CA, METADEX, AJ and JICST.