
6 Oxygen-Enhanced Combustion
approximately the same temperature and heat transfer
characteristics of an air/fuel system.
There are generally two methods of blending ue
gases into the combustion process. The rst is the
more traditional method of blending where ue gases
are extracted from the exhaust and recycled back to
the burner (see Figure 1.7), which is usually referred
to as ue or exhaust gas recirculation (FlGR) because
the recycle gases come from the ue (exhaust). This
method is also referred to as external ue gas recircu-
lation. An example of this method applied to oxy/fuel
combustion is given in reference [30]. Another example