Numerical Modeling and Simulation of Highly Preheated and Diluted Air Combustion Furnaces

This paper presents some of the results of the modeling and simulation of an industrial furnace under the conventional combustion as well as under the highly preheated and diluted air combustion (HPDAC) conditions. The results are obtained using a computer program written by authors in FORTRAN language. It was found that, the HPDAC offers a more uniform and relatively moderate gas temperature profile resulting in the reduction of NOx pollutant formation and also a larger flame indicating lower maximum local heat release rate. Higher thermal performance (up to 39%) and therefore lower fuel or energy consumption up to (30%) which result in reduction of CO2 pollutant emission to the environment, in addition to requiring a smaller chamber size for processing the same material/feed or increasing productivity for the same furnace size are also concluded. Finally, in this paper a modified concept and formula has been proposed and used to define the chemical flame shape and size.