化工进展 ›› 2018, Vol. 37 ›› Issue (07): 2635-2643.DOI: 10.16085/j.issn.1000-6613.2018-0022

• 工业催化 • 上一篇    下一篇

硫酸氢铵在钒基选择性催化还原催化剂表面的生成、作用及防治

张道军1, 马子然1, 孙琦1, 徐文强1, 李永龙1, 王宝冬1, 竹涛2, 林德海1, 季广辉3, 马静1   

  1. 1 北京低碳清洁能源研究所, 北京 102211;
    2 中国矿业大学(北京) 化学与环境工程学院, 北京 100083;
    3 神华河北国华定州发电有限责任公司, 河北 定州 073000
  • 收稿日期:2018-01-03 修回日期:2018-03-07 出版日期:2018-07-05 发布日期:2018-07-05
  • 通讯作者: 王宝冬,教授级高级工程师,青年千人计划专家,主要研究方向为大气污染控制;竹涛,教授,博士生导师,主要研究方向为大气污染控制。
  • 作者简介:张道军(1989-),男,博士,博士后,主要研究方向为大气污染控制。E-mail:zhangdaojun@nicenergy.com
  • 基金资助:
    中组部青年千人启动经费——洁净煤(燃煤电厂)污染物控制项目(GB9300120001)。

Formation mechanism, effects and prevention of NH4HSO4 formed on the surface of V2O5 based catalysts

ZHANG Daojun1, MA Ziran1, SUN Qi1, XU Wenqiang1, LI Yonglong1, WANG Baodong1, ZHU Tao2, LIN Dehai1, JI Guanghui3, MA Jing1   

  1. 1 National Institute of Clean-and-Low-Carbon Energy, Beijing 102211, China;
    2 School of Chemical & Environmental Engineering, China University of Mining & Technology(Beijing), Beijing 100083, China;
    3 Shenhua Hebei Guohua Dingzhou Power Generation Company Limited, Dingzhou 073000, Hebei, China
  • Received:2018-01-03 Revised:2018-03-07 Online:2018-07-05 Published:2018-07-05

摘要: 电厂燃煤锅炉低负荷运行导致脱硝装置烟气温度偏低,硫酸氢铵中毒影响低温脱硝催化剂的长期稳定运行。本文分析了硫酸氢铵的形成机理及其对选择性催化还原(selective catalytic reduction,SCR)催化剂的影响,提出控制烟气中SO3浓度是减缓甚至避免SCR催化剂中毒的关键。文章从工艺和催化剂设计角度详细总结和分析了脱硝装置前端和脱硝装置中SO3的控制方法,并总结了硫酸氢铵中毒催化剂的再生方法及其优缺点。分析表明,通过喷入碱性吸收剂降低脱硝装置前端SO3浓度的工艺和对催化剂组分及结构进行合理设计以减少脱硝装置中SO3生成的方法具有很强的实用性,是未来研究发展的重要方向。低温条件下长期运行难免导致催化剂失活,而在线升温是恢复中毒催化剂活性的良好方法,在工程设计中应考虑相应工艺。

关键词: 烟道气, 选择性催化还原, 二氧化硫氧化, 三氧化硫, 硫铵盐, 硫酸氢铵

Abstract: When the coal-fired power plant operates at low loads, the low temperature of the flue gas entering the denitrification device will result in the formation of ammonium hydrogen sulfate on the catalyst, decreasing its activity and performance. The formation mechanism of ammonium hydrogen sulfate and its effects on the SCR catalyst are analyzed. Following that, this paper suggests that reducing the concentration of SO3 in flue gas is the key to slow down or even to avoid the poisoning of SCR catalyst by ammonium hydrogen sulfate. The methods to reduce the concentration of SO3 in denitrification unit and other units are reviewed and analyzed from the aspects of process and catalyst design. And the regeneration methods for the poisoned catalyst and their advantages and disadvantages are also reviewed and discussed. We proposed several important research directions in the future to prolong the working life of the catalyst:①spraying alkaline absorbents to reduce the SO3 concentration before the flue gas goes into the denitrification unit to contact with NH3;②making a rational design of the composition and structure of the catalyst, since the SCR catalyst in the denitrification device also oxidize SO2 into SO3. However, despite of various methods to avoid catalyst poisoning, it is difficult to remain high activity for the SCR catalyst running under low temperature. To develop the regeneration method and build the device are also of importance. One promising way is to increase the catalyst temperature to decompose the ammonium hydrogen sulfate and regenerate the catalyst in operation.

Key words: flue gas, selective catalytic reduction (SCR), SO2 oxidation, sulfur trioxide, ammonia sulfate salts, ammonium hydrogen sulfate

中图分类号: 

京ICP备12046843号-2;京公网安备 11010102001994号
版权所有 © 《化工进展》编辑部
地址:北京市东城区青年湖南街13号 邮编:100011
电子信箱:hgjz@cip.com.cn
本系统由北京玛格泰克科技发展有限公司设计开发 技术支持:support@magtech.com.cn