Recent developments in heat recovery systems allow for preheating of combustion air up to temperatures of 1300 deg C, and, thus, fuel savings up to 60% are achievable. In conventional burner/furnace designs, the higher the combustion air temperature the higher the NOx emissions. However, the most recent developments allow for low NOx combustion using high temperature combustion air. The objective of this paper is to establish conditions under which industrial furnaces should be operated in order to maximise the efficiency and minimize the pollutant emissions including carbon dioxide. To this end, semi-industrial scale experiments have been carried out using natural gas and vitiated air at 1300 deg C. This article can be downloade in full free of charge from: www.metallurgi.kth.se/htc/skiva/presentations/weber.pdf
