论文部分内容阅读
提高CaO的固硫率是对煤炭燃烧污染防治的研究热点.本研究探索用催化剂提高CaO固硫率的可行性及其对固硫反应动力学的影响.用热天平测试了在CaO中添加不同催化剂的固硫反应的进程,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.以碱金属的盐类为催化剂,它们均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,而碱金属盐的负离子主要影响产物层扩散阶段的固硫反应.
Increasing the sulfur fixation rate of CaO is a hotspot in coal combustion pollution prevention and control.This study explored the feasibility of using catalyst to increase the sulfur fixation rate of CaO and its effect on the kinetics of sulfur fixation reaction.Furthermore, The process of sulfur fixation reaction and the equivalent particle model were used to deal with the experimental data.The kinetic parameters of the surface chemical reaction control stage and product layer diffusion control stage were calculated.The experimental results show that the initial stage of CaO sulfur fixation reaction is the stage of surface chemical reaction control , And later changed to the diffusion control phase of product layer.The alkali metal salts as catalysts all decreased the reaction activation energy in the chemical reaction control phase before the sulfur fixation reaction and decreased the activation energies in the order of Li, Na, K and Cs Decrease, while the negative ions of alkali metal salt mainly affect the product-layer diffusion stage of the sulfur-fixing reaction.