凹凸棒石改性钙基吸收剂循环碳酸化特性的试验分析  

Cyclic Carbonation Characteristic Analysis of Calcium-Based Sorbent Modified with Attapulgite

作　　者：单历元 李辉[1,2] 孟冰露 孟晶晶[1] 于有海[3] 闵永刚[1,2] 

机构地区：[1]西安建筑科技大学材料与矿资学院,西安710055 [2]陕西循环经济工程技术院,西安710055 [3]中国科学院西安光学精密机械研究所,西安710119

出　　处：《硅酸盐通报》2016年第10期3119-3125,3131,共8页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金项目(51274159);陕西省重大科技创新专项(2012zkc06-2)

摘　　要：钙基吸收剂在较高的温度下可有效的循环捕集烟气中的较低浓度的CO_2,通过升温释放出高浓度的CO_2。但其弊端在于随着CO_2释放/吸附的不断进行,吸收剂的烧结现象严重,CO_2的吸收效率也显著的下降,若仅采用钙基材料作为CO_2捕集剂,需不断的投入新鲜的吸收剂,消耗量较大。本论文以水泥工业为背景,研究其烟气中CO_2的捕集,并采用一维结构的凹凸棒对吸收剂进行表面修饰处理,来缓解吸收剂的烧结现象,以提升CO_2的吸收效率。试验结果表明:凹凸棒石物理吸附CO_2的量对钙基吸收剂碳酸化率的提高有一定的贡献,但此贡献要小于吸收剂抗烧结性能的提高所带来的贡献;凹凸棒石对颗粒粒径较大的吸收剂的改性效果较好;不改变钙基吸收剂的粒径,当将提纯凹凸棒石的粒径减小时,其改性效果进一步提高。Calcium-based sorbent can circularly capture low concentration CO_2 effectively in flue gas,and release high concentration CO_2 by raising temperature. But the disadvantage of Calcium-based sorbent was sintering seriously with the times of cyclic calcination/carbonation,so that Carbonation rate declined rapidly. If only using natural calcium-based sorbent as capture agent,the consumption of limestone is too large. This paper was based on the flue gas in cement industry,and used attapulgite which is abundant in the nature and with the one dimensional structure to modified the surface of limestone,with the effect of anti-sintering and carbonation rate(XN) was improved. The results showed that: attapulgite physical adsorption to CO_2 made contribution to the improvement of calcium-based sorbent carbonation rate(XN),however,the contribution was less than the improvement of sintering resistance; carbonation rate(XN) of attapulgite modified larger particle size sorbent was better; kept the particle size of calcium-based sorbent and reduced to particle size of purified attapulgite,its modified effect was further enhanced.

关 键 词：CO2捕集 凹凸棒石 钙基吸收剂 粒径 碳酸化率 

分 类 号：TQ172[化学工程—水泥工业]