The effect of CO2 addition on the flame behavior of a non-premixed oxy-methane jet in a lab-scale furnace

Abstract The dilution effect of carbon dioxide (CO 2 ) in an oxidizer was studied experimentally in a non-premixed oxy-methane flame. A lab-scale furnace with a slot-type burner was used as a model of an industrial furnace. The objectives of the current study are to investigate the flame stabilization, to analyze the flame spectra, and to study the flame behavior of non-premixed oxy-methane flames as the CO 2 mole fraction is varied in an oxidizer. The flame stabilization was estimated by changing the flow velocity at the fuel jet nozzle exit ( u F ) and the oxygen nozzle exit ( u Ox ) from u F  = 7–50 m/s for methane (CH 4 ) and from u Ox  = 10–120 m/s for oxygen (O 2 ), respectively. The experimental results indicate that the flame stabilization of non-premixed oxy-methane flames decreased with increases in the CO 2 mole fraction in the oxidizer. The flame spectra of non-premixed oxy-methane flames had a maximum intensity at the wavelength ( λ ) of λ  = 308 nm. The reaction zone of non-premixed oxy-methane flames was broadened by the addition of CO 2 to the oxidizer.