Simultaneous capture of metal, sulfur and chlorine by sorbents during fluidized bed incineration

Metal capture experiments were carried out in an atmospheric fluidized bed incinerator to investigate the effect of sulfur and chlorine on metal captu re efficiency and the potential for simultaneous capture of metal, sulfur a nd chlorine by sorbents. In addition to experimental investigation, the eff ect of sulfur and chlorine on the metal capture process was also theoretica lly investigated through performing equilibrium calculations based on the m inimization of system free energy. The observed results have indicated that , in general, the existence of sulfur and chlorine enhances the efficiency of metal capture especially at low to medium combustion temperatures. The c apture mechanisms appear to include particulate scrubbing and chemisorption depending on the type of sorbents. Among the three sorbents tested, calcin ed limestone is capable of capturing all the three air pollutants simultane ously. The results also indicate that a mixture of the three sorbents, in g eneral, captures more metals than a single sorbent during the process. In a ddition, the existence of sulfur and chlorine apparently enhances the metal capture process. (C) 2001 Elsevier Science Ltd. All rights reserved.