钙基脱硫剂用于冶炼烟气脱硫的模拟与实验  

Simulation and experimental study on smelter off-gas desulfurization using calcium-based desulfurizer

作　　者：昌晶[1] 胡修德 田红景[3] 远富启 许静文 郭庆杰 CHANG Jing;HU Xiude;TIAN Hongjing;YUAN Fuqi;XU Jingwen;GUO Qingjie(College of Resources and Environment, Qingdao Agricultural University, Qingdao 266109, Shandong, China;State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering, Ningxia University, Yinchuan 750021, Ningxia, China;College of Chemical Engineering, Qingdao University of Science ＆ Technology, Qingdao 266042, Shandong, China)

机构地区：[1]青岛农业大学资源与环境学院,山东青岛266109 [2]省部共建煤炭高效利用与绿色化工国家重点实验室(宁夏大学),宁夏银川750021 [3]青岛科技大学化工学院,山东青岛266042

出　　处：《化工学报》2018年第5期2233-2241,共9页CIESC Journal

基　　金：国家自然科学基金项目(51608291;51106077);山东省自然科学基金项目(ZR2017QB019);青岛市自主创新计划项目(16-5-1-30-jch);宁夏引进科技创新团队项目(煤炭清洁利用);煤炭高效利用与绿色化工国家重点实验室开放课题(2017-K19)~~

摘　　要：提出了一种应用钙基脱硫剂脱除冶炼烟道气中高浓度SO_2并回收硫单质的方法。通过热力学模拟多种硫化物与SO_2之间的反应,筛选得出硫化钙(Ca S)适合作为化学链脱硫技术的脱硫剂,它在400~650℃范围内可将SO_2还原为单质硫,生成的固相产物为Ca SO_4而非Ca O。通过固定床反应器内的脱硫实验,发现温度对脱硫率和硫单质回收率影响较大。在400~650℃范围内温度越高,脱硫率和硫单质回收率越大;当温度高于600℃时,脱硫率和硫单质回收率基本相等。提高空速,则会降低脱硫率和硫单质回收率,但两者的差值随空速增大逐渐减小。当烟气中SO2浓度小于1%时,脱硫率维持在99.8%基本不变;SO_2浓度升至3.45%后,平均脱硫率急剧下降至92.1%;SO_2浓度越高,平均脱硫率越低。硫单质回收率随SO_2浓度增大存在一最佳范围。在脱硫反应后期,粒径较大的脱硫剂颗粒脱硫性能较低。SEM照片表明了脱硫剂颗粒随反应温度的升高团聚现象更为明显,XRD表征证明了反应中SO_2气体被还原为升华硫颗粒。A method was developed to recover elemental sulfur from smelter off-gas with high SO2 content. Based on thermodynamic simulation of reactions between some sulfides and SO2, calcium sulfide（Ca S） was demonstrated to be a novel chemical desulfurizer. SO2 was reduced to elemental sulfur by reacting with Ca S in temperature range from 400℃ to 650℃ and direct solid product was Ca SO4 rather than Ca O. The experimental desulfurization in a fixed bed reactor showed that reaction temperature had a strong effect on SO2 removal efficiency and sulfur recovery ratio. When temperature was increased within the range of 400℃ and 650℃, both SO2 removal efficiency and sulfur recovery ratio were raised gradually. When temperature was higher than 600℃, SO2 removal efficiency was approximately equal to sulfur recovery ratio. Increasing gas velocity reduced SO2 removal efficiency, sulfur recovery ratio, and difference between these two. SO2 removal efficiency remained at 99.8% at SO2 concentration below 1% but dropped sharply to 92.1% at SO2 concentration up to 3.45%. Average SO2 removal efficiency declined gradually when SO2 concentration was continuously increased. With increase of SO2 concentration, sulfur recovery ratio exhibited an optimal range. At late stage of desulfurization, large particle size of Ca S decreased SO2 removal efficiency. SEM photos showed that desulfurizer particles agglomerated more obviously at increase of reaction temperature. XRD patterns verified sublimated elemental sulfur particles in the reduction of SO2 by Ca S.

关 键 词：烟道气 回收 还原 脱硫率 

分 类 号：X701.7[环境科学与工程—环境工程]