Mercury Removal in A Fgd Slurry

One of the leading sources of environmental mercury contamination comes from the burning of coal in coal-fire power plants. In power plants equipped with FGD's, wet flue gas desulfurization units, mercury can enter the environment through two pathways. The trace amounts of mercury, present in the coal, can either be emitted in the exhaust gasses or it can bond to the gypsum that is formed as a byproduct of the sulfur dioxide sequestration. In second case the mercury is considered to be stabilized; however, the gypsum byproduct is used make wallboard and this manufacturing processes occurs at temperatures high enough to volatilize the mercury.

The aim of this study is to find an effective sorbent, which can be inserted into a FGD slurry to prohibit mercury emission from either of the two aforementioned pathways. Research is being conducted in two steps. The first step is to investigate iron, sulfur, and activated carbon sorbents in batch system to develop an understanding of capacities of these sorbents in a FGD slurry. The second step is to test promising sorbents in a bench scale simulation of a FGD in order to ascertain data that can be used to model larger scale implementations.