| The amendments to the Clean Air Act of 1990 have focused attention on 189 chemicals cited as potential hazardous air pollutants. Among the list are eleven metallic substances, i.e., antimony, arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, mercury, nickel, and selenium. Most coal in the United States contains trace amounts of these metals, so metallic pollutants are produced during coal combustion.; This study investigated the potential of employing suitable sorbents to capture trace metallic substances during fluidized bed coal combustion. Experiments were carried out in a 25.4 mm (1{dollar}sp{lcub}primeprime{rcub}{dollar}) quartz fluidized bed coal combustor enclosed in an electric furnace. The metals involved in the study were cadmium, lead, and chromium, and the sorbents tested included bauxite, zeolite, and lime. In addition, potential metal-sorbent reactions were also identified through performing chemical equilibrium analyses based on the minimization of system free energy. |
