Mercury removal properties of current flue gas purification devices in coal-fired power plants

In order to study the mercury emission characteristics and mercury removal properties of the ex- isting flue gas purification devices (such as desulfurization/denitration/dust removal equipments) in a lig- nite coal-fired power plant,the Ontario (OHM) method and the cold atomic absorption spectrum analysis method were employed to detect the concentration of zero-valent mercury (Hg0), oxidation state mercury (Hg2+ ) ,particle state mercury (Hgp) and total Hg (HgT) in the flue gas during combustion and gas emis- sion. The results show that,the SCR denitration device's mercury removal effect was not obvious, the dust collector had a certain removal effect for the particle state mercury, and the desulfurization equipment mainly removed the oxidation state mercury in the flue gas. Therefore, the mercury removal efficiency of the existing flue gas purification device in coal-fired power plants is not very high (only 33. 94%).