Sulfation phenomena in fluidized bed combustion systems

Fluidized bed combustors (FBCs) are noted for their ability to capture SO2 in situ via direct reaction with Ca-based sorbents. However, despite more t han 30 years of intensive study of sulfation processes in atmospheric FBC b oilers and numerous laboratory studies, there are still many uncertainties and disagreements on the subject. In particular, the mechanisms of the sulf ation reaction are still not properly understood, and there is dispute over the explanation of the well-known temperature maximum for optimum sulfur c apture found in FBC boilers. This paper discusses these points of contentio n and suggests the most probable mechanisms and explanations for the variou s phenomena seen with sulfur capture, based on current literature and perso nal experimentation. (C) 2001 Elsevier Science Ltd. All rights reserved.