Particle Size Distribution and Enrichment of Alkali and Heavy Metals in Fly Ash on Air and Oxy-Fuel Conditions from Sludge Combustion

Comparative tests in air and oxy-fuel combustion were conducted a 30 kWth circulating fluidized bed (CFB) pilot plant for waste sludge combustion. General characteristics of the CFB, such as pressure profiles, temperatures along bed, flue gas composition, different under conditions. At bottom fly ash, alkali heavy metals had distributions The particle size distribution ash from was dominated by coarse particles, over 2.5 μm size, whereas with combustion, most particles submicron approximately 0.1 μm, smaller quantity formed than Mass fractions Al, Ca, K, below found ashes higher those Submicron formation Cr, Ni, Cu, Zn occurred more during it did