7 - Conversion of solid fuels and sorbents in fluidized bed combustion and gasification

Abstract

This chapter deals with solid fuels and sorbent conversion during fluidized bed combustion and gasification. The conversion of solid fuels is discussed with reference to fuel properties, fuel devolatilization and volatiles conversion, char combustion and gasification reactions, mechanisms controlling char conversion rate, regimes and models of char conversion, and char particle temperature. As regards the second topic, the discussion is focused on calcium-based sorbents for in-situ desulphurization, calcination and sulphation processes, reaction models, controlling mechanisms, reactivation by water- and steam-hydration of spent sorbents and fluidized bed ash properties. Other sorbent conversion processes, such as calcium looping technique, are also mentioned.