Nitrogen oxides emitted from gas burners are mainly thermal NOxand prompt NOx.On the basis of analyzing the combustion mechanisms in low NOx gas burner

a low NOx gas burner was designed in combination of subsonic super mixing

opposed swirl nonlinear dynamics and biased staged combustion technology.Moreover

relative retrofitting was performed on a natural gas fired boiler.By carrying out performance tests before and after the reformation

the influences of certain key parameters such as boiler load

central gas

central air flow rates and rotation angle of gas guns on NOxemission were investigated.The results reveal that

within the whole operating ranges

NOxemission from the gas burner developed above can be controlled below 100mg/m3

which fulfills the latest environmental protection requirements.