Application of gaseous oxidized mercury reduction technology in mercury continuous emission monitoring system

Accurate monitoring of oxidized mercury in coal-fired flue gas is a prerequisite for developing an optimal mercury emission control strategy, and it is a crucial part of mercury continuously emission monitoring system(Hg-CEMS). The wet chemical sampling method, the solid adsorbent sampling method and the mercury continuously emission monitoring system were discussed and compared, and then an overview of divalent mercury reduction technology was presented, which was the key of Hg-CEMS. The research progress of oxidized mercury wet chemical reduction method, high temperature pyrolysis reduction and solid-state catalytic reduction were described. For high-temperature pyrolysis reduction, the study is mainly focused on the heat storage capacity and the ability to remove acid gas as well as oxidizing components of filling materials; for solid-state catalytic reduction, it is mainly focused on the active components of solid catalyst, reaction temperature windows, and preferential selectivity for mercury reduction. Combined with the current study results and application status of the oxidized mercury reduction technology in flue gas, the research ideas and application prospects of the conversion technology of oxidized mercury in Hg-CEMS are proposed. © 2021, Central South University Press. All right reserved.