论文信息 - CFD MODELING OF THE OXY-FUEL COMBUSTION OF VICTORIAN BROWN COAL IN DROP TUBE FURNACE AND 3MW PILOT SCALE BOILER

CFD MODELING OF THE OXY-FUEL COMBUSTION OF VICTORIAN BROWN COAL IN DROP TUBE FURNACE AND 3MW PILOT SCALE BOILER

With Victorian brown coal being responsible for electricity generation in the state, minimising the environmental impact of its combustion is vital for the sustainable use. Oxy-fuel technology is one promising and cost-effective option for carbon capture and sequestration in both short and medium terms. Due to the presence of abundant moisture within it, i.e. up to 70 wt%, Victorian brown coal combustion possesses numerous distinct characteristics in oxy-fuel combustion. In this study, a series of CFD modelling has been conducted by using Ansys-Fluent to clarify pulverized coal flame ignition and propagation in oxy-fuel process, and its variation with coal moisture content. First, the simulation focused on particle temperatures under different oxy-fuel conditions in a labscale drop tube furnace (DTF). The pulverized coal particle temperature in 27 vol% O2 balanced by CO2 was found agreeing with conventional air-combustion mode. Such a phenomenon was further confirmed by simulating coal combustion in a 3 MW pilot boiler. Moreover, modelling a wet coal containing 30% moisture indicated the expansion of pulverized-coal flame length and char ignition delay. NOMENCLATURE p A

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