摘要
提高 CaO的固硫是对煤炭燃烧污染防治的研究热点.采用热天平测试研究在 CaO中添加不同碳酸盐的固硫反应的进程,并采用等效粒子模型处理实验数据,计算了表面化学反应控制阶段及产物层扩散控制阶段的动力学参数.实验及计算结果表明, CaO固硫反应初期为表面化学反应控制阶段,后期转为产物层扩散控制阶段.以碱金属碳酸盐为催化剂,能使固硫反应前期的化学反应控制阶段的反应活化能下降,并按 Li, Na, K, Cs的顺序依次递减.将不同的碳酸盐作为固硫促进剂的 CaO加入型煤中,都得到了较高的固硫效率.
Kinetics of CaO desulfurization reaction and the effects of some alkali carbonates on it was investigated by thermogravimetric analysis method. The kinetic behavior of desulfurization can be explained by grain model. The activity energy of surface reaction (Ea) and the activity energy of product layer diffusion (Ep) were determined by using the model. The overall rate of desulfurization is controlled initially by surface chemical reaction, and then shift to product layer diffusion control. Some alkali carbonates can decrease the activation energy in the surface chemical reaction. Ea dereases orderly when the added catalysts changed from Li, Na, K to Cs, while Ep increases.
出处
《煤炭转化》
CAS
CSCD
2000年第4期59-62,共4页
Coal Conversion
基金
国家重点基础研究发展规划项目!(G19990222051)
清华大学基础研究基金!(JC1999051).