CeCl_3/活性炭纤维去除模拟烟气中单质汞的实验研究

Experimental research of removing elemental mercury from simulated flue gas by CeCl_3-loaded activated carbon fiber

运用等量浸渍法制备了一系列CeCl3/ACF去除剂,研究了不同负载量、不同温度和不同烟气成分对其脱汞效果的影响,并采用BET和XRD等手段对去除剂的理化性质进行了表征.结果表明,负载CeCl3后显著改善了活性碳纤维的脱汞能力,在本实验条件下,CeCl3的最佳负载量为5%(质量分数);当反应温度低于140°C时,去除剂的脱汞效率随着温度的升高而升高,当反应温度超过140°C后,去除效率随温度的升高而下降;通过考察NO、SO2和水蒸气对ACF脱汞效果的影响发现,NO对单质汞脱除具有一定的促进作用,不同浓度的NO与单质汞的脱除效率之间存在正相关关系;SO2对单质汞的脱除具有抑制作用,且脱除效率随着SO2浓度的增加而下降;水蒸气对单质汞的脱除具有阻碍作用.

ACF impregnated with CeCl3 was developed and some related experiments including reaction temperature,CeCl3 loading value and flue gas component on Hg0 removal efficiencies were conducted.In addition,Brunauer-Emmett-Teller（BET） and X-ray diffractometer（XRD） analyses were used to characterize the samples.The results showed that CeCl3 significantly improved the mercury removal capacity of activated carbon fiber in the simulated flue gas.In this experimental condition,the optimal loading value of CeCl3 was 5%（mass fraction）;when the temperature was below 140°C,the removal efficiency of CeCl3/ACF for Hg0 was enhanced with the increase of the temperature and then decreased above 140°C;moreover,the effect of NO,SO2 and water vapor on the removal of mercury were studied.It has been found that NO had a certain facilitating role on removal of elemental mercury,and there was a positive relationship between the concentrations of NO and the removal efficiency of Hg0;SO2 inhibited the removal of Hg0,and the removal efficiency decreased with the increase of SO2 concentrations;the Hg0 removal efficiency of CeCl3/ACF was hindered by the water vapor.