Mineralogical and Elemental Composition of Fly Ash from Pilot Scale Fluidised Bed Combustion of Lignite, Bituminous Coal, Wood Chips and Their Blends

Mineralogical and elemental composition of fly ash from pilot scale fluidised bed combustion of lignite, bituminous coal, wood chips and their blends were investigated. The blend of coal and wood chips adds aluminum and iron to the ash and the trace element levels were generally in the same ranges as for wood fly ash. Fly ash deriving from the combustion of pure lignite and pure wood chips had a low loss-on-ignition (LOI) level. The mineralogical composition of the fly ashes depended on the components of the blends and the combustion temperature. The results indicated that the presence of minerals namely anhydrite and portlandite was more possible when the used fuels contain calcium.