Method for treating fly ash in a fluidized bed boiler and boiler plant

Abstract

A boiler plant comprises a fluidized bed boiler having a furnace (1), a flue gas duct (5) exiting the furnace, and a sorting device (8) which is arranged to separate a first fraction from the fly ash entering the flue gas duct, as well as a side duct (9) for leading the first fraction away from the sorting device (8). The boiler plant comprises a separator (10) for separating a first fly ash fraction from the flue gases flowing in the side duct (9). The sorting device (8) is arranged to separate into the side duct (9) the flue gases from a flow entering the flue gas duct (5). The flow in the side duct is more concentrated with respect to the fly ash and has a smaller gas volume than a flow that remains in the flue gas duct (5) after the sorting device (8). As to its hazard classification, the first fraction of fly ash obtained by the separator (10) corresponds to bottom ash.

Dependencies are inferred from the claim text.