宣钢优特钢用活性石灰反应过程动力学研究

Dynamics model of producting active lime in Xuanhua Steel

摘要: 对宣化钢铁公司石灰厂所用的石灰石的分解过程进行了动力学研究.以升温速率分别为10、15、20、25和30℃/min的方式将过200目筛子的石灰石粉末加热到1000℃,通过测量其热重曲线,得出分解过程的机理方程为F(α)=(1-α)^-1;所用碳酸钙的热分解反应的速率常数为k=54325\rme^-\frac98873RT.通过对(0.02 m×0.02 m×0.02 m)的石灰石样品在1223、1323和1423 K进行的分解实验,确定了CO₂在该石灰石生成CaO过程中的扩散系数和温度的关系为\lg D=-\frac2506T+2.28,得到了石灰石分解的动力学模型,并用此模型作了预测,与实际吻合较好.

Abstract: The limestone decomposed to activity lime by TG at the rates of 10, 15, 20, 25 and 30℃/min was studied. The decomposing mechanism equation is F(α)=(1-α)^-1, and the reaction rate constant is k=54325\rme^-\frac98873RT. It is founded that the diffused constant in the decomposition of lime from limestone is \lg D=-\frac2506T+2.28, a dynamics model of decomposing time of limestone with the decomposition ratio X_B was revised, and the finished time of limestone decomposition at 1423 K was forecasted with this model. It indicates that the forecasted results agree very well with the experiment results.