宣鋼優特鋼用活性石灰反應過程動力學研究

Dynamics model of producting active lime in Xuanhua Steel

摘要: 對宣化鋼鐵公司石灰廠所用的石灰石的分解過程進行了動力學研究.以升溫速率分別為10、15、20、25和30℃/min的方式將過200目篩子的石灰石粉末加熱到1000℃,通過測量其熱重曲線,得出分解過程的機理方程為F(α)=(1-α)^-1;所用碳酸鈣的熱分解反應的速率常數為k=54325\rme^-\frac98873RT.通過對(0.02 m×0.02 m×0.02 m)的石灰石樣品在1223、1323和1423 K進行的分解實驗,確定了CO₂在該石灰石生成CaO過程中的擴散系數和溫度的關系為\lg D=-\frac2506T+2.28,得到了石灰石分解的動力學模型,并用此模型作了預測,與實際吻合較好.

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.