单塔双循环烟气脱硫系统结晶过程的模拟研究  

Simulation Research on Crystallization Process in Single-tower and Double-cycle Gas Desulfurization System

作　　者：方志强 蒋惠梦 史贺贺 谷小兵 赵怡凡 刘健[1] 王兰蕙 王祖武[1] FANG Zhiqiang;JIANG Huimeng;SHI Hehe;GU Xiaobing;ZHAO Yifan;LIU Jian;WANG Lanhui;WANG Zuwu(School of Resource and Environmental Sciences, Wuhan University, Wuhan 430079, China;Datang Environment Industry Group Co. Ltd., Beijing 100080, China)

机构地区：[1]武汉大学资源与环境科学学院,湖北武汉430079 [2]大唐环境产业集团股份有限公司,北京100080

出　　处：《环境科学与技术》2018年第5期73-79,共7页Environmental Science & Technology

基　　金：武汉市科技局2015年高新技术成果转化及产业化计划项目(2015060303010164)

摘　　要：单塔双循环湿法烟气脱硫系统中,二水硫酸钙结晶是影响该工艺运行的关键技术之一。在单因素条件下分别研究晶种浓度、晶种粒径、相对过饱和度(RS)和p H值对硫酸钙结晶速率、晶体粒径、形貌以及结垢特性的影响。结果表明:晶种浓度和粒径对二水硫酸钙结晶影响显著,当晶种过100目筛,适当增加晶种浓度(C≤2 g/L),有利于晶体快速生长,且晶体生长得更为粗壮和均匀,结垢量也不断减少;相对过饱和度增大会大大提高结晶速率,但适中的相对过饱和度(RS=6)更利于形成以片状和棒状为主且粒径分布均匀的晶体,结垢量相对较少;反应溶液p H在5~6之间时,结垢量少,对晶体形貌有利且与脱硫塔中实际酸碱度相符。以上结论对单塔双循环脱硫工艺具有一定的参考价值。Crystallization of calcium sulphate dihydrate is one of the key technologies that affect the operation of the process in single-tower and double-cycle wet flue gas desulfurization system. In a bench scale experiment the effects of parameters such as seed concentration, seed size, relative super-saturation（RS） and p H value on the crystallization rate, crystal size and morphology as well as scale formation were studied. The experimental study suggested that seed crystal concentration and grain size greatly affected the crystallization of calcium sulphate dehydrate, and when seed crystal exceeded 100 mesh, properly increasing seed concentration（C≤2 g/L） was conducive to rapid crystal growth, which led to the advantages： crystal growth was more uniform and the amount of scale reduced; with the increases of relative supers-saturation, the crystallization rate was greatly improved, but the moderate super-saturation condition（RS=4） would be more favorable to formation of lamellar and rod-like crystals with uniform particle size distribution, amount of scale is relatively small; when p H value of the reaction solution ranged between 5 and 6, conforming to the actual p H value in the desulfurization tower, the amount of scale declined and crystalline grain became bigger with the ideal morphology.

关 键 词：单塔双循环 二水硫酸钙 结晶 相对过饱和度 

分 类 号：X701.3[环境科学与工程—环境工程]