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Show This proprietary technique is being further developed improving both the equipment as well as the thermal aspects of the operation. Upcoming test will involve a 1 MY firing rate furnace and later on an industrial unit. Natural gas/pure oxygen flame is a primary low NOx technology for very high temperature processes, as glass melting for instance. This fact has been recently demonstrated on an industrial furnace. However, when better performances have to be achieved under unfavourable conditions (such as high nitrogen content in natural gas), pulsating combustion is a very simple technique which can yield up to 90% NOx emission reduction. Recent pilot experiments show that these results is obtained without significant changes of the heat transfer to the charge. High overall flame temperature and heat transfer efficiency of the pure oxygen flame are maintained. There is no flame dilution or recirculation which may alter the heat transfer. Pulsated combustion represents a technical solution which benefits from all the advantages associated to pure oxygen-based combustion with low NOx emissions. 7. References A. AI-HADDAD and N. AI-BINALLY, Int. J. Heat and Fluid Flow, Vol 10, n02, June 1989. E. BRIFFA and P. STADDON , Symposium on Pulsed Combustion Application, Proceedings Vol 1, Atlanta (Georgia), 1982. O. CHARON et al., NOx formation in glass melting furnaces, modeling and experimental results, AFRC fall International Symposium, October 8-10 1990. A. PUTNAM F. BELLEST and J. KENTFIELD, Prog. Energy Combust. Sci., Vol 12, pp 43-79, 1986. 17 |