含铁粉尘碳酸化反应动力学研究

Study on Carbonation Reaction Kinetics of Ferrous Dust

通过热重实验对含铁粉尘碳酸化反应动力学进行了研究,建立了碳酸化反应的未反应收缩核模型,分析了反应温度对反应控制阶段动力学特性参数的影响规律.结果表明,提高反应温度有利于碳酸化球团的转化;碳酸化反应温度由400℃升高到600℃时,CaO转化率明显增大,800℃达到最大;碳酸化反应的总速率受到内扩散和界面化学反应共同控制,反应前期化学反应为限制环节,反应速率较快,反应后期内扩散为限制环节,反应速率变慢;在200～800℃的反应活化能为11.091kJ/mol.

The carbonation reaction kinetics of ferrous dust was studied using thermal experiment for carbonate pellets. The un-reacted shrinking core model for carbonation reaction was set. The influence of reaction temperature on reaction kinetics parameters in the reaction control stage was analyzed. The results showed that raising reaction temperature was beneficial to transformation of carbonation pellets. While the temperature rising from 400 ℃ to 600 ℃, the conversion rate of CaO increased obviously, and reached the highest at 800 ℃. The total rate of carbonation reaction was controlled by internal diffusion and interracial chemical reaction together. The reaction was controlled by chemical reaction in the initial reaction stage, the reaction rate was faster. Then the reaction was controlled by internal diffusion, the rate slowed down. At the temperatures of 200-800℃, its activation energy was 11.09 kJ/mol.