3 - Minimization of Hg and trace elements during coal combustion and gasification processes

Abstract

Trace element (TE) emissions, especially mercury, have grown in concern due to their environmental and health impact. Coal combustion is one of the major sources of these emissions to air. The final fate of these elements is determined by complex mechanisms and depends on fuel properties, combustion parameters, and power plant configuration. However, a classification based on their partitioning and volatility has been established. Current international and national legislation is becoming increasingly stringent, and technologies to establish emission limit values have been investigated. Existing air pollutant control devices are a cost-effective option, and although removal efficiencies depend on TE and operational conditions, high removal efficiencies can be achieved. The more volatile TEs are captured to a much lower extent in coal-fired power stations. For that reason, specific technologies mainly based on sorbent injection have been developed.