BEHAVIOR OF MERCURY IN QUENCH TOWERS WITH APPLICATION TO INCINERATORS

摘要

Mercury is one of a number of pollutants that persist in the environment and bioaccumulate in the food chain. Because of its toxicity and the potential for bioaccumulation, mercury emissions to the environment are the subject of environmental regulation. U.S. EPA estimates that the majority of the man-made emissions of mercury come from point sources of combustion. There are currently emission limits on mercury from certain categories of combustion sources, including cement kilns and incinerators burning hazardous waste. When fuels or wastes containing mercury are combusted in incinerators, the combustion exhaust gases contain mercury compounds. Air pollution control devices such as acid gas scrubbers remove gaseous ionic mercury compounds like HgCl2, but not gaseous elemental mercury. The formation of gaseous ionic compounds from elemental mercury is governed by the composition of the flue gas and the time-temperature history. In this paper, we review the chemistry of mercury in combustion systems and develop a model applicable to the transformations of mercury in incinerators and removal in quench towers.