Oxy-fuel combustion is the process of burning fuel using pure oxygen instead of air as the primary oxidant. Since the nitrogen component of air is not heated, fuel consumption is reduced, and higher flame temperatures are possible. Historically, the primary use of oxy-fuel combustion has been in the welding and cutting of metal.
Advantages:
1. The mass and volume of the flue gas are reduced by approximately 75%.
2. less heat is lost in the flue gas.
3. The size of the flue gas treatment equipment can be reduced by 75%.
4. The flue gas is primarily CO2, suitable for sequestration.
5. Low nitrogen oxide/NOXes production.
Challenges are high installation and operating costs. Installed at small-scale power plants still needs to be adopted by oil refineries. Linde Engineering has several references.
Simple process of Oxy-fuel combustion is shown by Linde.
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