Emission characteristics of the 0.03 MW oxy-fuel combustor

Emission characteristics of the 0.03 MW oxy-fuel combustor have been experimentally investigated under a wide operating range of velocity and quarl angle. To simulate the NO emission characteristics of industrial oxy-fuel furnaces, we mixed 3% nitrogen by supplied oxygen with pure oxygen. When a quarl is not fitted, the flame length decreased with increasing inlet fuel or oxidizer velocity, mainly because of the increase in turbulent intensity. In the case of the high-speed injection of fuel or oxidizer without a quarl, NO emission levels decrease because high-speed injection enhances the entrainment of product gas to the flame zone as well as decreases the overall combustion residence time. When a quarl is fitted, the flame length increases with expanding quarl angle because of the decrease in turbulent intensity. The NO emission level increases with expanding quarl angle because both the entrainment of product gas is prevented and the overall combustion residence time is increased with the installation of a quarl.