School of Energy and Power Engineering, Jiangsu University , Zhenjiang, Jiangsu 212013, China.
Environ Sci Technol. 2014 Oct 21;48(20):12181-9. doi: 10.1021/es501966h. Epub 2014 Oct 3.
In this article, a novel technique on removal of elemental mercury (Hg(0)) from flue gas by thermally activated ammonium persulfate ((NH4)(2)S(2)O(8)) has been developed for the first time. Some experiments were carried out in a bubble column reactor to evaluate the effects of process parameters on Hg(0) removal. The mechanism and kinetics of Hg(0) removal are also studied. The results show that the parameters, (NH4)(2)S(2)O(8) concentration, activation temperature and solution pH, have significant impacts on Hg(0) removal. The parameters, Hg(0), SO2 and NO concentration, only have small effects on Hg(0) removal. Hg(0) is removed by oxidations of (NH4)(2)S(2)O(8), sulfate and hydroxyl free radicals. When (NH4)(2)S(2)O(8) concentration is more than 0.1 mol/L and solution pH is lower than 9.71, Hg(0) removal by thermally activated (NH4)(2)S(2)O(8) meets a pseudo-first-order fast reaction with respect to Hg(0). However, when (NH4)(2)S(2)O(8) concentration is less than 0.1 mol/L or solution pH is higher than 9.71, the removal process meets a moderate speed reaction with respect to Hg(0). The above results indicate that this technique is a feasible method for emission control of Hg(0) from flue gas.
本文首次开发了一种通过热活化过硫酸铵((NH4)(2)S(2)O(8))从烟道气中去除元素汞(Hg(0))的新方法。在鼓泡柱反应器中进行了一些实验，以评估工艺参数对 Hg(0)去除的影响。还研究了 Hg(0)去除的机理和动力学。结果表明，(NH4)(2)S(2)O(8)浓度、活化温度和溶液 pH 等参数对 Hg(0)去除有显著影响。Hg(0)、SO2和 NO 浓度等参数对 Hg(0)去除的影响较小。Hg(0)通过过硫酸铵、硫酸盐和羟基自由基的氧化而被去除。当(NH4)(2)S(2)O(8)浓度大于 0.1 mol/L 且溶液 pH 小于 9.71 时，热活化(NH4)(2)S(2)O(8)对 Hg(0)的去除符合一阶快速反应。然而，当(NH4)(2)S(2)O(8)浓度小于 0.1 mol/L 或溶液 pH 大于 9.71 时，Hg(0)的去除过程符合中速反应。上述结果表明，该技术是一种从烟道气中控制 Hg(0)排放的可行方法。
