In order to reduce nitrogen oxides(NOx)produced from gas combustion

a new low-NOxburner for gas combustion process was designed.This burner applies the special staged combustion technology of fuel and combustion gas as well as the subsonic mixing technology and others to form an opposed firing effect by internal and external layer of fuel.Thus

the fuel and the combustion air can be mixed more evenly in the furnace so as to reduce the local high temperature and NOxformation.Moreover

by using the CFD software

this paper simulated the temperature field and NOxformation inside the furnace

and carried out low NOx gas burner retrofit on a 120t/h boiler.The temperature field and NOxemission concentration before and after the retrofitting were compared numerically and experimentally.The results verified this novel low NOx gas burner can reduce the local high temperature and NOxformation during combustion

which can provide references for low NOxcombustion retrofit for gas boilers.