摘要
基于乙二胺四乙酸亚铁螯合剂络合吸收的NO和NO_2协同净化工艺,一级净化采用铁屑填料床,利用螯合物吸收、铁屑还原净化NO,二级吸收采用鲍尔环清水喷淋塔,考察协同净化效果。结果表明:当NO进口质量浓度约为200mg/m~3、NO_2进口质量浓度约为70mg/m~3、螯合剂为0.02mol/L、液气比为3L/m~3、空塔气速为0.078m/s的条件下,一级出口NO降至75mg/m~3左右;在一级吸收塔螯合剂为0.02mol/L、液气比为3L/m~3和二级吸收塔氧化度(NO_2占NO_x的体积分数)为50%、液气比为4L/m~3的条件下,二级出口NO、NO_2分别可稳定在20、8mg/m~3左右。
The synergistic purification of NO and NO_2 was realized based on complexation and absorption of ethylene diamine tetra acetic acid chelating agent.The first stage purification was carried out by iron packing bed,using chelate absorption and iron reduction,to decrease the concentration of NO.The second stage absorption was implemented in Bauer ring water spray tower,and the effect of synergistic purification was investigated.The results showed that when the mass concentration of NO was about 200 mg/m~3,NO_2with 70 mg/m~3,the concentration of chelating agent at 0.02mol/L,the liquid gas ratio at 3L/m~3,and the air velocity of air tower with 0.078m/s,the first order export NO was reduced to about 75mg/m~3.NO and NO_2of the second stage outlet was stabilized at 20and 8mg/m~3 respectively,under conditions of the chelating agent of the first order absorption tower at 0.02 mol/L,the liquid gas ratio at 3L/m~3 and the second absorption tower oxygen degree of 50%,the liquid gas ratio at 4L/m~3.
引文
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