亚硫酸镁对NO2的液相吸收及产物离子分布  

Absorption of NO2 by magnesium sulfite and ions distribution in liquid phase

作　　者：张梦笛 应孟悦 刘越[1] 吴忠标[1,2] ZHANG Meng-di;YING Meng-yue;LIU Yue;WU Zhong-biao(College of Environmental and Resource Sciences,Zhejiang University,Hangzhou 310058,China;Zhejiang Provincial Engineering Research Center of Industrial Boiler and Furnace Flue Gas Pollution Control,Hangzhou 310058,China)

机构地区：[1]浙江大学环境与资源学院,浙江杭州310058 [2]浙江省工业锅炉炉窑烟气污染控制工程技术研究中心,浙江杭州310058

出　　处：《浙江大学学报（工学版）》2020年第10期1978-1985,共8页Journal of Zhejiang University：Engineering Science

基　　金：国家重点研发计划资助项目(2017YFC0210201)。

摘　　要：以亚硫酸镁模拟氧化镁湿法脱硫浆液对NO2进行吸收,考察不同操作条件下的NO2吸收效率及吸收液中主要离子的分布情况.结果表明,O2对吸收过程的影响很大,NO2主要通过与SO32-之间发生的链式反应在液相中产生SO42-和NO2-,O2会与NO2发生竞争作用,极大地消耗了SO32-,导致脱硝效率迅速下降.抗氧化剂邻苯二酚的添加可以抑制SO32-的氧化,且添加的浓度越高,抑制效果越好.溶液的pH值主要通过影响S(Ⅳ)的存在形态来影响吸收反应,当pH值较低时,吸收反应的速率降低,且在酸性条件下,NO2-易发生歧化反应转化为NO3-.NO2-的累积将会在一定程度上降低NO2的吸收,其他阴离子NO3-、SO42-及Cl-对NO2的吸收无明显影响.金属阳离子例如Mn2+及Co2+会加速SO32-的氧化,在一定程度上影响NO2的吸收.Magnesium sulfite was employed as simulated magnesia wet flue gas desulfurization(WFGD)slurry for NO2 absorption.The NO2 absorption efficiency and the distributions of aqueous ions in the absorption solution under different operating conditions were analyzed.The experimental results show that the presence of oxygen greatly influences on NO2 absorption.The absorption of NO2 mainly occur via a series of chain reactions with SO32-,finally generating SO42-and NO2-.Oxygen can competitively consume SO32-,resulting in a great decrease in NO2 absorption efficiency.The addition of catechol can retard the consumption of SO32-by O2 so that NO2 absorption efficiency can maintain,and this effect is enhanced with an increase of content.The pH value affects the absorption reaction through the existing form of S(Ⅳ).The denitrification efficiency reduces under acidic conditions,and increased NO3-content can be observed owing to the disproportionation of NO2-.The accumulation of nitrite ions can slightly inhibit the absorption of NO2,while other anions such as NO3-,SO42-and Cl-have no significant effects.Some metal cations like Mn2+and Co2+can accelerate the oxidation rate of SO32-,which affect the absorption of NO2 to some extent.

关 键 词：亚硫酸镁 二氧化氮 液相吸收 离子分布 链式反应 

分 类 号：X701[环境科学与工程—环境工程]