Emission Control of Trace Heavy Metal Elements in Coal-fired Power Plants

The trace heavy metal elements occur in coal during the coal-forming process and enrich on the bottom ash or fly ash after coal combustion, then escape into the air in the form of particulate or vapour, causing certain environmental hazards. In this paper, control methods for three important trace heavy metal elements, As, Pb, and Se, which were defined as hazardous air pollutants (HAPs) in CAAA, are compared and classified, the emissions control technologies can be mainly implemented by the pre-combustion processing, the in-combustion processing, and the post-combustion processing as well as other aspects. In view of different elements, the corresponding removal methods are proposed.