Computer Simulation of NOx Formation in Boilers

Understanding of how and where NOx formation occurs in industrial boiler is very important for efficient and clean operation of utility boilers. This study aims to numerically simulate the NOx formation using a 3D model furnace of an industrial boiler. The studied boiler is a 160 MW and is gas fired with natural gas. The boiler combustion model is a 3D problem that involves turbulence, combustion, radiation in addition to NOx modeling. The 3D model is developed by dividing the volume of the furnace into 371000 control volumes with more concentration of grids near solid walls and regions of high property gradients. The simulation study provided the 3D temperature distribution as well as the rate of formation of the NOx in the combustion chamber and in the exhaust gas at various operating conditions.