NH3对SCR催化剂Hg0催化氧化性能的影响

作为我国主要的汞污染源之一，燃煤电厂汞污染物排放控制是我国环保标准的要求。通过改性SCR催化剂和卤化物添加等方法将Hg⁰氧化为Hg²⁺，进而通过后续设备进行脱除，是提高汞脱除率的有效方法。但对我国而言，这类结合现有环保设备的联合脱除方法都面临着SCR入口高浓度NH₃的抑制作用。为此，基于文献调研，总结了NH₃对SCR催化剂Hg⁰氧化性能的影响，以及卤素存在条件下NH₃对Hg⁰氧化性能的影响，分析了改性催化剂及卤化物添加对Hg⁰氧化率的提高机理，进而对应地分析了NH₃对Hg⁰氧化的抑制机理。研究结果为实际燃煤电厂提高SCR设备Hg⁰氧化率提供了参考。

Influence of NH3 on Hg0 Oxidation Performance of SCR Catalyst

As one of the main sources of mercury pollution in China, the emission control of mercury pollutants from coal-fired power plants is the requirement of China's environmental protection standards. Hg⁰ is oxidized to Hg²⁺ by means of modified SCR catalyst and halide addition in coal, and then removed by subsequent equipment, which are effective methods to improve mercury removal rate. For these methods based on air pollution control device (APCD) in China, the inhibition of high concentration NH₃ at SCR inlet is a problem to solve. Therefore, based on literature research, the influence of ammonia injection on Hg⁰ oxidation performance under the combined effect of SCR catalyst and halide addition in coal was concluded. The mechanism of improving Hg⁰ oxidation rate by modified catalyst and halide addition was analyzed. The corresponding inhibition mechanism of NH₃ on Hg⁰ oxidation was also analyzed. The research results provide a reference for the coal-fired power plants to improve Hg⁰ oxidation rate of SCR.