海水改性分子筛吸附剂脱除燃煤烟气中Hg^0的实验研究

Study of Using Seawater Modified Molecular Sieves Adsorbents to Remove Hg^0 from Coal-Fired Flue Gas

由于在吸附剂中引入卤族元素可以极大地促进其对燃煤烟气中Hg-0的脱除,考虑到海水中含有丰富的氯元素,因此采用海水改性来提高吸附剂脱除Hg-0的效率。在氧气体积分数为6%的氮氧（94%N2＋6%O2）基本气氛下进行了改性吸附剂脱除Hg-0的活性测试。研究表明：经海水改性后提高了吸附剂的脱汞效率且改性吸附剂对Hg-0主要以化学吸附的方式脱除;改性吸附剂的最高脱汞效率达到90%,相比于Na（13X）分子筛原样的脱汞效率提升了约40%,表明通过海水改性来提高吸附剂脱汞效率是可行的。

The Hg^0 removal from coal-fired flue gas using molecular sieves adsorbents could be greatly promoted by introduction of halogen elements. In this work, considering the richness of Cl element, seawater was employed to modify molecular sieves adsorbents to improve its Hg^0 removal efficiency. As a resuit,the chemical adsorption of Hg^0 for the modified adsorbent was significantly enhanced and thus the promoted removal performance was achieved. The Hg^0 removal activity tests of the modified adsorbents were carried out under N2/O2 basic atmosphere with 6% volume fraction of oxygen. The highest Hg^0 removal efficiency of the modified adsorbent could reach a high level of 90% ,40% higher than that of the raw Na（13X） molecular sieves adsorbent. This study suggested that the Hg^0 removal efficiency of molecular sieves could be effectively improved after modified by seawater. It was expected to provide a new idea for developing adsorbents for cost-effective and highly efficient elemental mercury removal.