Oxy-fuel fluidized bed combustion using Victorian brown coal: An experimental investigation

Oxy-fuel combustion is a promising power generation technology due to its potential for easier CO2 separation and capture. This when combined with fluidized bed combustion offers additional advantages like fuel flexibility, uniform temperature distribution, low NOx emissions and in-bed SO2 capture via sorbent addition. Although few studies have addressed the oxy-fuel fluidized bed combustion of lignites, its applicability using Victorian brown coal has remained unexplored. From experiments in a bench-scale fluidized bed under oxy-fuel combustion condition using Victorian brown coal, this study finds that the flue gas CO2 concentration increases with oxygen concentration and steam in the feed gas while the effect of temperature is modest between 850 °C and 900 °C. The addition of steam lowers the trace element retention in ash; this may indirectly affect their partitioning behavior. These results are important for selection of operating conditions for oxy-fuel fluidized bed combustion of Victorian brown coal.

• First ever study on oxy-fuel fluidized bed combustion of Victorian brown coal.
• Flue gas CO2 concentration increased slightly with temperature.
• CO2 concentration increased with oxygen and steam concentration in the feed gas.
• Addition of steam lowered the trace elements retention in ash.