Numerical Study of Reduction of NOx Emission by High Temperature Air Combustion Technology

A numerical study on Nox emission from an industrial furnace utilizing high temperature air combustion (HTAC) technology was done. The basic concept of the regenerative burner including heating a diluting of fresh air by flue gas was implemented in a two-dimensional furnace model. Governing equations in conjunction with a turbulence model and an overall chemistry model were solved using an implicit numerical scheme. Effect of temperature and O2 concentration of preheated airflow on Nox emission from a furnace were investigated. Numerical results show a drastic increase in Nox emission when temperature or O2  concentration of preheated airflow increases. High combustion efficiency and low Nox emission can be achieved when the inlet airflow is preheated up to a high temperature, for instance, about 1500 ºK , and O2  reduced to about 5%.