Modelling and Dynamic Studies of the Second Generation Oxy-Fired CFB Boiler

Climate change due the temperature increase in the world is one of the biggest challenges for the mankind. The need to develop low carbon power production is obvious already nowadays and specially in the future. In the EU 7th Framework Program's project O2GEN (Optimization of Oxygenbased CFBC Technology with CO2 capture), modelling plays a major role in evaluation of an oxy-firing and circulated fluidized bed based solution for low carbon energy production. In the earlier, 1st generation CCS capable plant concept, the conditions in the oxidant streams and furnace side were close to air-firing conditions, and the boiler could continuously produce electricity both in air and oxy modes. This paper deals with the 2nd generation concept, which major differences and improvements include duplication of the plant power capacity, increasing the oxygen content up to 40 mol% in the oxidant streams, focusing on continuous operation only in oxy-firing mode, and heat integration to increase the overall efficiency. This paper presents the 2nd generation concept modelling, simulation results as well as the first implications on the dynamic behavior, illustrated with a firing mode switching case.