Evaluation of Oxy-coal Combustion Modelling at Semi-industrial Scale

Duringthe oxy-fuelcombustion processpulverizedcoalisburntinan atmosphere consistingofpureO2mixedwith recycled fluegas whereas during the conventional process air serves as the only oxidant. This entails specific conditions regarding thermo-physical properties which impact both combustion characteristics and heat transfer. Accordingly, adjustments within CFD codes are required in order to maintain accuracyand prediction quality criteria within simula–tions of oxy-coal combustion. The CFD code AIOLOS was used to evaluate recent oxy-coal specific implementations concerning the global chemistry mechanism and the heat transfer. For validation purposes extensive tests have been carried out at IFK's semi-industrial scale furnace (500kWth). Simulations have been performed for both, conventional air-firing and oxy-coal combustion conditions with US bituminous coal, and a comparison of simulation results and corresponding experimental data is given. In general, satisfactory agreement is observed.