CONTROL OF TOXIC METAL EMISSIONS FROM COMBUSTORS USING SORBENTS - A REVIEW

This paper constitutes a review of the control of toxic metal emission s using sorbents. The objective of sorbent-injection methods is to eff ectively capture the metal species (preferably transform it to an envi ronmentally benign form) and to suppress the fraction in the submicrom eter mode. The design of an effective sorbent-injection methodology th us requires an understanding of the fate of the metallic species and i ts transformation pathways (transfer to the gas phase, subsequent chem istry at high temperatures, and aerosol formation and growth dynamics) in the combustor. Several different sorbent methodologies used for me tals capture are discussed, and a mechanistic description is provided. The need for further experimentation and pilot scale testing is also emphasized.