含湿Ca(OH)_2颗粒脱硫反应特性的模型研究

Modeling the reactivity of aqueous Ca(OH)_2 particle

在半干法脱硫装置中脱硫反应主要表现为含湿Ｃａ（ＯＨ）２ 颗粒与ＳＯ２ 的反应．在液相反应溶解和传质理论基础上，通过对含湿Ｃａ（ＯＨ）２ 颗粒内反应机理的研究分析提出了含湿Ｃａ（ＯＨ）２ 的脱硫反应模型．通过分析和计算可发现，含湿Ｃａ（ＯＨ）２ 颗粒由于液相的存在使反应特性与干燥Ｃａ（ＯＨ）２ 颗粒相比发生明显变化．反应速率随含湿量的提高而增加，含湿颗粒的粒径减少和钙转化率提高均会使反应速率下降，当温度低于某一临界温度Ｔｃｒ时，温度升高反应速率增加，当温度超出某临界温度Ｔｃｒ时，反应速率随温升而下降．

The reaction between aqueous Ca(OH)\-2 particle and SO\-2 is the mainly sulfation reaction in semi\|dry FGD system.Based on reaction,dissolution and mass transfer theory and by the way of reaction mechanism analysis.A desulphurization model of aqueous Ca(OH)\-2 particle is proposed.It can be found that the sulfation reaction mechanism of aqueous Ca(OH)\-2 particle is obviously different from dry Ca(OH)\-2 particle,and the reaction rate increased with water content in aqueous sorbent and decreased with particle size and conversion ratio.The temperature effect on reaction rate of aqueous sorbent is relatively complex and there is a critical temperature point in the related curve.Below this point,the reaction rate increased with temperature increasing,while alove the point,the reaction rate decreased with the temperature increasing.The results supply the optimum parameters for semi\|dry FGD system designed.