活化碳酸钾溶液吸收CO_2的动力学研究  

Kinetics of CO_2 Absorption by Promoted Aqueous Potassium Carbonate Solution

作　　者：申淑锋[1] 冯晓霞[1] 赵瑞红[1] 

机构地区：[1]河北科技大学化学与制药工程学院,河北省药物化工工程技术研究中心,河北石家庄050018

出　　处：《高校化学工程学报》2013年第5期903-909,共7页Journal of Chemical Engineering of Chinese Universities

基　　金：河北省自然科学基金(B2012208022);国家自然科学基金(21206029);河北省引进留学人员资助项目

摘　　要：化学溶剂吸收法是实现燃煤电厂烟气中CO2控制排放的有效途径之一。与有机胺溶剂相比,碳酸钾溶液吸收CO2具有溶剂成本和再生能耗等方面的优势,近年来再次受到人们的关注和重视。今在湿壁柱装置中,研究了碳酸钾溶液体系在不同浓度和不同温度下吸收CO2的速率,同时讨论了不同活化碳酸钾溶液对吸收CO2的归一化传质通量的影响。结果表明,加入1%(wt)硅酸钾可以明显提高碳酸钾溶液吸收CO2的速率,相同条件下活化后吸收CO2的归一化传质通量增加约1倍。采用快速拟一级吸收动力学模型,获得硅酸钾活化碳酸钾溶液吸收CO2的本征反应速率常数为8.35×1013exp(-6789.66/T)m3·kmol-1·s-1。Carbon dioxide absorption using chemical solvents is one of the developed and feasible methods used to reduce CO2 emission from coal-fired power plants. Using potassium carbonate as absorbent has a number of advantages, such as solvent costs and regenerating energy consumption, over the amine based solvents, therefore it has been paid more attention in recent years. In this work, the CO2 absorption rates in tmpromoted K2CO3 solution at various concentrations and temperatures were investigated in a wetted wall column and the effect of different promoters added into aqueous carbonate solution on the normalized mass-transfer flux was discussed. Results show that the addition of 1%（wt） potassium silicate into the aqueous carbonate solution could significantly enhance the CO2 absorption rate, and the normalized mass-transfer flux obtained by the promoted K2CO3 solution increases 100% during the investigated temperature range. Based on the fast pseudo-first-order reaction model, the inherent kinetic constant for reaction between potassium silicate and C02 was obtained as 8.35×10^13exp（-6789.66/T） m^3·kmol^-1.s-1.

关 键 词：二氧化碳吸收 碳酸钾 硅酸钾 活化剂 动力学 

分 类 号：TQ028.14[化学工程] TQ013.2