HCl干式净化过程平衡浓度计算及其应用

Determination of HCl Equilibrium Concentration and Its Application During HCl Dry Removal Process

利用固体产物生成的能耗分析 ,在传统的热力学平衡公式中加入修正项 ,计算 HCl气体在利用石灰类吸收剂对其进行干式净化过程中的平衡浓度 ,首次提出气固反应过程中反应气体的平衡浓度随着固体反应率的增大而上升的概念。计算结果表明 :吸收剂在达到一定的反应率以后 ,HCl的平衡浓度随温度的上升而下降。利用平衡浓度随反应率和温度的变化特征可以解释传统的热力学平衡式所不能解释的一些实验现象 ,并可以利用平衡浓度来预测利用钙基吸收剂干式净化焚烧炉排烟中 HCl的净化效率和吸收剂用量。预测结果可以判断干式净化的使用范围。

Based on energy consumption analysis,thermodynamical equilibrium equation for gas solid reaction was modified to take into account chemical potential consumption on mechanical work to push away product layers for new product crystals to grow.According to the modified equilibrium equation,equilibrium conceentrations are calculated for HCl,a typical acidic gas in incienerator flue gas during its dry removal process with lime sorbents at different temperatures and under different sorbent conversions.It is found firstly that HCl equilibrium concentration increases with conversion rate of sorbents and decreases with temperature rising after reaching certain conversion rates.The changing characteristics of the equilibrium concentration with tempratures and sorbent conversions can explain some phenomena that cannot be explained with traditional thermodynamical equilibrium theory.With the help of equilibrium concentrations,dry scrubbing efficiency of HCl and sorbent dosage can be estimated quantitatively;also limits for dry scrubbing application and direction for raising dry removal efficiency can be predicted.