A Comparison among Different Sorbents for Mercury Adsorption from Flue Gas

The adverse effects of mercury on human health are a well-known problem, as mercury is a persistent toxic pollutant. Among the anthropogenic sources, the coal fired utility boilers, the combustion of municipal solid waste (MSW) and the cement production process are the main sources of mercury emission. The problem of mercury abatement is particularly tricky, because during combustion up to 98% of mercury is rapidly volatized without being captured by means of particulate control devices. The present work is focused on the removal of mercury compounds in flue gas by dry adsorption process on solid sorbents, which is considered a BAT (Best Available Technology) for mercury pollution control. In this paper, a comparison among different commercial solidsorbents (i.e. several commercial activate carbons) used by this research group to adsorb metallic and divalent mercury from combustion flue gas is presented. The tested activated carbon are HGR carbon and Darco G60 carbon, impregnated or not. The comparison is carried out in terms of isotherm curves, for the temperatures ranging from 90°Cto 200°C, which is an interval typical of the exhaust gas treatment line downstream an industrial combustor