Evaluation of trace element mobilization and control under different fluidized bed combustion scenarios

Abstract

As consequence of its relatively abundant reserves compared to other energy sources, coal will continue to be widely employed in power plants. To reduce coal’s negative impact on the environment, new approaches have been evaluated and adopted by various countries in recent years to minimize CO2 emissions. Initial developments focused on the selection of new fuels (such as biomass fuels) to combine with coal to reduce emissions from coal combustion, whereas subsequent approaches aimed at implementing new processes for CO2 capture and storage, such as oxy-fuel combustion. In addition, coal combustion is one of the main anthropogenic sources of trace elements (TE) emitted to the atmosphere. The increasing knowledge acquired as to the impact of these pollutants in the environment has led to more restricted emission standards for some of these elements and to increased research on the technologies and pathways to control these emissions. This article reviews the main factors involved in TE capture by comparing results obtained for Hg and other TEs under different control scenarios. Both the effect of novel combustion processes and the potential of different pollution control techniques toward these pollutants are discussed.