Thermodynamic Study on the Utility Oxy-Fuel Boiler with Different Oxygen Volume Fractions

Oxy-fuel combustion technology is one of the most promising technologies for capturing CO2 emitted from coal-fired power plants. For the operation of an oxy-fuel combustion utility boiler, its thermodynamic features should be clarified. For this purpose, a calculation model for oxy-fuel combustion boiler was established, and the thermodynamic characteristics of a 2102 t/h oxy-fuel utility boiler were explored. The results show that at a given oxygen volume fraction, the start-up process of an oxy-fuel boiler can be completed in a short time. Along with the increasing of the oxygen volume fraction, from 22 to 29%, it showed a strong effect on furnace radiant surfaces and furnace volumes. And that variation of CO2 enthalpy played a vital role in the flue gas enthalpy, the oxygen volume fraction was shown to affect the various parts of the furnace differently. The calculations in present research could contribute to the oxy-fuel boiler design and operation.