Numerical simulation on the emission of NOx from the combustion of natural gas in the sidewall burner

The NOx produced from industrial facilities is a serious environmental problem in China. In this work, the NOx emission from the combustion of natural gas in the sidewall burner was investigated by using computational fluid dynamics method. To achieve the low-NOx emission, the sidewall burner structure was optimized involving the width of the primary premixed gas outlet, the secondary fuel gas nozzles number and angular spacing. The mixing rate of fuel gas and air could be improved by increasing the width of primary premixed gas outlet, and the lowest NOx emission of 32.8 ppm was achieved at the width of 8 mm. The NOx emission was remarkably reduced with the increasing of nozzles number, where 28.33 ppm of NOx emission and 357.35 ppm of CO were obtained at 4 nozzles. The combustion performance and NOx emission was improved as well as NOx emission was reduced at the angular spacing of 55?, compared to that of 30?, 35?, 40?, 45?, 50? and 60?.