中国电力 ›› 2019, Vol. 52 ›› Issue (4): 151-155,160.DOI: 10.11930/j.issn.1004-9649.201806025

• 节能与环保 • 上一篇    下一篇

商用SCR催化剂对单质汞(Hg0)的氧化作用研究

曲立涛1,2, 李彩亭2, 陶莉3   

  1. 1. 华电电力科学研究院有限公司, 辽宁 沈阳 110180;
    2. 湖南大学环境科学与工程学院, 湖南 长沙 410082;
    3. 国网湖南省电力公司电力科学研究院, 湖南 长沙 410007
  • 收稿日期:2018-06-13 修回日期:2018-07-08 出版日期:2019-04-05 发布日期:2019-04-16
  • 作者简介:曲立涛(1982-),男,硕士,工程师,从事火力发电厂污染物控制技术研究,E-mail:litao-qu@chder.com

Study on the Oxidation Effects of Commercial SCR Catalyst on Elemental Mercury (Hg0)

QU Litao1,2, LI Caiting2, TAO Li3   

  1. 1. Huadian Electric Power Research Institute Co., Ltd., Shenyang 110180, China;
    2. College of Environmental Science and Engineering, Hunan University, Changsha 410082, China;
    3. State Grid Hunan Electric Power Corporation Research Institute, Changsha 410007, China
  • Received:2018-06-13 Revised:2018-07-08 Online:2019-04-05 Published:2019-04-16

摘要: 为开发对烟气NOx和汞等多种污染物具有良好联合脱除效用的一体化新型催化剂,研究了目前商用SCR脱硝催化剂对单质汞(Hg0)的氧化作用及其影响因素,探求Hg0氧化反应机理。实验结果表明:SCR催化剂对烟气中的Hg0具有一定的氧化作用,但在催化剂最佳反应温度250~300 ℃时,其对Hg0的最大氧化效率仍低于50%。在低浓度NO和5%O2同时存在的情况下,催化剂对Hg0有相对较高的氧化效率;SO2存在时,Hg0的氧化明显被抑制,SO2对催化剂的毒性基本不可逆转;NH3与Hg0在吸附过程中存在竞争关系,因而NH3的存在降低了催化剂对Hg0的氧化效率;H2O对Hg0的氧化有十分明显的负面影响。

关键词: 燃煤电厂, 烟气脱硝, SCR催化剂, 单质汞(Hg0), Hg0氧化效率

Abstract: In order to develop a novel integrated catalyst with better joint removal effects on various pollutants such as NOx and mercury in the flue gas, the oxidation effects of commercial SCR denitration catalyst on elemental mercury (Hg0) and its influencing factors were studied in this paper. The oxidation reaction mechanism of Hg0 was also explored. The experimental results show that the SCR catalyst has some certain oxidation effects on Hg0 in flue gas. However, its maximum oxidation efficiency on Hg0 is still below 50% even at the optimum reaction temperature of 250~300 ℃. In the presence of low concentration of NO and 5% O2, the catalyst has a relatively high oxidation efficiency for Hg0. While in the presence of SO2, the oxidation of Hg0 was apparently inhibited, and the toxicity of SO2 to the catalyst was basically irreversible. Moreover, there exists a competitive relationship between NH3 and Hg0 in the adsorption process. So the presence of NH3 reduces the oxidation efficiency of Hg0 by the catalyst. It also appears that the presence of H2O has significant negative impact on the oxidation of Hg0.

Key words: coal-fired power plants, flue gas denitration, SCR catalyst, elemental mercury (Hg0), oxidation efficiency of Hg0

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