Dry desulfurization in a circulating fluidized bed (CFB) with chain reactions at moderate temperatures

Abstract

A series of experiments in a circulating fluidized bed (CFB) pilot plant has explored a new dry desulfurization process, using the NOx in the flue gas and a new sorbent that has been prepared from fly ash and lime. Various desulfurization operating parameters were tested for the thermodynamic, chemical, and dynamic states for temperatures of 523-673 K. The NOx increased the calcium conversion ratio in the desulfurization process. In addition, with the NOx, the desulfurization by product was determined to be mostly CaSO4, instead of CaSO3, as a result of the chain reaction caused by the NOx. Therefore, the NOx in the flue gas can improve the efficiency of the dry desulfurization process. © 2005 American Chemical Society.