化工进展2018，Vol.37Issue(3)：822-831,10.DOI:10.16085/j.issn.1000-6613.2017-0797
NH3-SCR工艺中硫酸铵盐的生成与分解机理研究进展
Research progress on the formation and decomposition mechanism of ammonium-sulfate salts in NH3-SCR technology
摘要
Abstract
Selective catalytic reduction denitrification method with ammonia as the reducing agent (NH3-SCR) has high denitrification efficiency,good selectivity and high level of refinement,and thus, is the most widely used flue gas denitrification technology in coal-fired power plants and other industries at present. However,when the flue gas flows through the SCR catalyst,SO2in the flue gas is oxidized into SO3by the V2O5. Ammonium sulfate and ammonium bisulfate are then produced when SO3reacts with NH3and water vapor. These ammonium-sulfate salts will probably be deposited in the catalyst,air preheater and affiliated equipment when the flue gas temperature is below their condensation temperatures,which may cause many serious problems. In this review,the formation mechanism of ammonium-sulfate salts is introduced at first. Then the main factors that affect the formation of ammonium-sulfate salts are summarized in terms of concentration of the reactants and the reaction temperature. Afterwards,the deposition of the ammonium-sulfate salts and its harm are analyzed. The decomposition mechanism of ammonium-sulfate salts is introduced,and the interaction between the catalyst and ammonium bisulfate is discussed in detail,whose influence on the decomposition of ammonium bisulfate is pointed out. Finally,the measures for controlling the formation of ammonium-sulfate salts are proposed. Overall,systematic research on the formation and decomposition mechanism of ammonium-sulfate salts in the NH3-SCR process provides theoretical basis for the deactivation and regeneration of SCR catalysts,the development of low temperature SCR catalysts and the optimization of operation and design of the related equipments in coal-fired power plants,which therefore deserves further research.关键词
选择性催化还原/催化剂/硫酸铵盐/生成与分解机理/沉积物Key words
selective catalytic reduction(SCR)/catalyst/ammonium-sulfate salts/formation and decomposition mechanism/deposition分类
化学化工引用本文复制引用
唐昊,李慧,杨江毅,蔺卓玮,庄柯,陆强,李文艳..NH3-SCR工艺中硫酸铵盐的生成与分解机理研究进展[J].化工进展,2018,37(3):822-831,10.基金项目
国家重点基础研究发展计划(2015CB251501)、北京市科技新星项目(Z171100001117064)及中央高校基本科研业务专项资金项目(2015ZD08,2016YQ05). （2015CB251501）
