A PROCESS FOR PRODUCING VALUE ADDED ASH FROM FLY ASH WITH HIGH UNBURNT CARBON AND A SYSTEM

摘要

A fly ash processing system comprising: (a) a storage silo or facility (9) for storing high carbon fly ash, having various levels of loss on ignition, (b) connected to a screw feeder(10) on a level slightly above the fluidization zone in a fluidized bed combustor (1), (c) the fluidized bed combustor having a conventional fluidized bed of me solid fuel provided with nozzles (2) for impinging preheated air, characterized in, (d) there being a preheat start up burner (11) for preheating air received from a forced draft an (3), for preheating air stream and supplying it at pressure below the nozzles, (e) mere being provided a closed loop recycle system (4) within me fluidized bed combustor for receiving the product flue gas and separating high carbon solids and recycling same to the fluidized bed combustor while allowing flue gases with tow carbon solids to leave from the recycle system (4), (f) die recycle system being in conjunction with a heat exchanger (5) for exchanging heat with cold water (8) and to produce steam thereby cooling the flue gases, (g) the heat exchanger (5) being also connected to a dust collector (6) upstream for recovering for recovering cooled, value added product ash dust collector having a product collection system (12), and an an induced fan (7) for withdrawing clean gas from the dust collector and to pass it to the exhaust (13).