OCR Text |
Show Although necessarily sophisticated in mode of operation, it has proven long term reliability in the field. Because of the many desirable features it incorporates, it is more expensive than most conventional burners, but the economics are favorable compared with other options if lower NOx levels are required. Since some of the existing and proposed regulations may require NOx emissions to be limited to 150 ppm or lower, only fuels that contain small amounts of organic nitrogen will be suitable for use even with the best burner technology available today. The authors suggest that further work is needed in developing better methods of forecasting expected NOx levels from a given fuel under specified conditions in a known type of burner and furnace configuration. It is hoped that improvements in continuous field measurement techniques for NOx will be developed and universally accepted. ACKNOWLEDGEMENTS: The authors gratefully acknowledge the support and help of D.M. Radford and G.H. Leaver, both of Urquhart Engineering Company Ltd. in providing some results and reference material, and W . H. Wheeler for permission to use some previously unpublished work. REFERENCES Matsui Yasuji & Nomaguchi Tamotsu - Spectroscopic Study of Prompt Nitrogen Oxide Formation Mechanism in Hydrocarbon-Air Flames Combustion and Flame 32,205-214 (1978) Michelfelder, S.; Heap, M.P.; Lowes, T.M. - The Effect of Burner Construction and Burner Parameters on the Emission of N O x from Natural Gas, Heavy Fuel Oil and Pulverised Coal Flames - IFRF presentation of Chemical Engr. Congress - Milano, Italy - April 1977. Siddiqu, A.; Tenini, J.W.; Killion, L.S. - Control Nox Emissions from Fixed Fireboxes - Hydrocarbon Processing - Oct. 1976. 13/14 |