Impact of direct oxygen injection on flame stability and overall burnout during oxyfuel combustion

This experimental study investigated oxy-fuel combustion characteristics with and without direct oxygen injection. Temperature distribution, gas composition and coal conversion were measured. The combustion tests were performed with a 100 kW swirl burner at TUM´s oxyfuel combustion test rig. The recycle ratio was set to 67% and either 0%, 2.5% or 5% of the total added oxygen was injected as pure oxygen using an additional lance. The direct injection of O2 leads to a hot and highly reactive zone close to the burner. Thus, the injection supports flame stability and prevents flame detachment. NO formation is enhanced due to the higher temperatures. Without injection the overall and carbon conversion is higher.      «

This experimental study investigated oxy-fuel combustion characteristics with and without direct oxygen injection. Temperature distribution, gas composition and coal conversion were measured. The combustion tests were performed with a 100 kW swirl burner at TUM´s oxyfuel combustion test rig. The recycle ratio was set to 67% and either 0%, 2.5% or 5% of the total added oxygen was injected as pure oxygen using an additional lance. The direct injection of O2 leads to a hot and highly reactive zone...     »