Thermal ash agglomeration process

摘要

A process and apparatus for thermal agglomeration of high melting temperature ashes in fluidized bed processes is disclosed. Carbonaceous material to be combusted, incinerated or gasified is introduced into a fluidized bed supported on a perforated sloping supported grid through which a fluidizing gas is injected. An upflowing discharge control gas is injected through a density/size solids withdrawal conduit in communication with the base of the perforated sloping support grid. Positioned within the solids withdrawal conduit is a central jet pipe through which fuel and oxidant are injected into the base of the fluidized bed forming a hot temperature zone in which ash melts and agglomerates. Positioned above the perforated sloping support grid and peripherally mounted through the reactor wall are one or more burners through which fuel and oxidant are injected into the fluidized bed forming supplemental hot temperature zones in which ash melts and agglomerates. The temperature of the supplemental hot zones is controlled independent of the bulk-bed temperature of the fluidized bed by the amount of fuel injected through the burners and can be maintained substantially higher than the bulk-bed temperature, thereby enabling the agglomeration of higher melting temperature ashes.