鼓泡反应器中Na_2S对低浓度NO_x的吸收  

Absorption of nitrogen dioxides with sodium sulfide solutions in bubbling reactor

作　　者：付鹏艳 童华[1] 杨迪[1] 

机构地区：[1]北京化工大学环境科学与工程系,北京100029

出　　处：《环境工程学报》2016年第8期4424-4428,共5页Chinese Journal of Environmental Engineering

摘　　要：实验研究了在鼓泡反应器中硫化钠溶液吸收低浓度NO_x的吸收特性,分析了NO_x、O_2、Na_2S和Na OH浓度对吸收过程的影响,以及被吸收NO2的形态。结果显示,Na2S浓度在15.8和47.5 mmol·L^(-1)时,气相中NO2浓度变化对吸收率影响不明显,但在0.30~3.25 mmol·L^(-1)时,NO2浓度变化对吸收率有较大影响。气相中的O2会加速吸收反应,但同时也引起吸收剂的额外消耗。当Na2S溶液中加入Na OH,浓度达到0.1%时,可强化NO_2的吸收。NO_x中NO含量增加会导致吸收率下降,即使有Na OH的条件下,也未观察到NOx氧化度为0.5时NO与NO2的协同吸收效应。Na2S溶液将被吸收的NO2一部分还原为N2,一部分还原为NO-2。Effects of NO2,O2,Na2 S,and alkalinity on the absorption of low-concentration NOxby sodium sulfide solution in a bubbling reactor were empirically evaluated; the speciation of the absorbed NO2 was also discussed. The results showed that when the Na2 S concentration was in the range of 15. 8 to 47. 5 mmol·L^-1,the effect of the NO2 concentration on the absorption efficiency was poor; however,the effect was pronounced when the concentration of Na2 S solution was 0. 30 to 3. 25 mmol·L^-1. Oxygen in the simulated flue gas did not decrease the NO2 absorption efficiency,but led to extra consumption of Na2 S. The NO2 absorption efficiency could be augmented by 0. 1% Na OH in the Na2 S solution. When the NO content in NOxincreased,the efficiency of NOxabsorption declined. Even in the presence of Na OH,no synergistic effect of NO and NO2 on the absorption was observed at a NOxoxidation degree of 0. 5. The absorbed NO2 was converted into N2 and NO-2by Na2 S solution.

关 键 词：Na2S溶液 NO2 吸收 

分 类 号：X511[环境科学与工程—环境工程]