(1. 北京科技大学 钢铁冶金新技术国家重点实验室,北京 100083;
2. 北京科技大学 期刊中心,北京 100083)
摘 要: 研究红土镍矿的脱水机理及还原过程动力学。结果表明,红土镍矿在升温过程中主要进行自由水的脱除、针铁矿的分解、高岭石及蛇纹石的脱羟基反应和蛇纹石类矿物的第二段脱羟基反应;红土镍矿还原过程可分为3个阶段,第一阶段的控速环节是化学反应,预焙烧和未焙烧红土镍矿的活化能分别为90.21和63.12 kJ/mol;第二阶段和第三阶段控速环节是扩散,红土镍矿的活化能逐渐增大。
关键字: 红土镍矿;动力学;热分析;直接还原
(1. State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China;
2. Journals Publishing Centre, University of Science and Technology Beijing, B)
Abstract:The dehydration mechanism and reduction process dynamics of laterite nickel ore were studied. The results indicate that the dehydration of free water, the decomposition of goethite and the dehydroxylation reaction of kaolinite and serpentine as well as the second period reaction of dehydroxylation for serpentine mineral all take place in the process of heating. The reduction of laterite nickel ore consists of three stages. Chemical reaction is the controlling unit in the first stage, the activation energies of the precalcined and unroasted laterite nickel ores are 90.21 and 63.12 kJ/mol, respectively. Diffusion is the dominant link in the following two stages, in which the activation energy of laterite nickel ore gradually increases.
Key words: laterite nickel ore; dynamics; thermal analysis; direct reduction