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Show most often was the control of emissions. Next came incineration. If the "incineration boom" really is coming, then we had better learn how to live with it. If the incineration boom isn't coming, then we had better come up with commercially available alternatives that are acceptable to the general public. Consequently, we enthusiastically support the International Flame Research Foundation's initiatives on the incineration of wastes and welcome any help the combustion R&D community can provide. Conclusion While it may be that the expanded use of alternative fuels would be "good," perhaps in synergistic combination with cogeneration, on balance today's economic and environmental . pressures do not augur well. To the contrary, they force emphaSis on more and better use of the traditional gaseous fuels. In the proceedings of the first Symposium on the Fluid Mechanics of Combustion, sponsored by ASME some 15 years ago, it was observed that combustion has traditionally been a science in chemistry but an empirical art in deSign, that we really understand very little about the fluid mechanics of combustion. What does "two feet per million" really mean? Despite a certain fondness and naive faith among contractors and designers for "specifying" the length of a flame based upon its heat release, the answer is, not much. Quoting a comprehensive report published by the Ingenieurs Bureau in The Netherlands, "It has often been seen that a flame for no apparent reason changes from long and slender into flat and broad, and vice versa." "For my burner in my firebox, what flame will I get?" "What changes will produce the flame that I really want?" Those are good questions that are largely unanswerable today except by firing up the burner in its firebox. We can really use some help there from the combustion R&D community and some good work is going on. An oil refinery or a petrochemical plant is a place in which heat is exchanged. The heat comes from combustion. This leads us to a healthy selfinterest in good-running furnaces and what makes them that way. Today in programs like the one sponsored by the International Flame Research Foundation, a better understanding of combustion aerodynamics is emerging that will put burner design on a firmer footing, with obvious benefits for industrial furnace operation. And in programs like the United States Department of Energy's study of oxygen enriched combustion there is the outside chance that the dual imperatives of energy conservation and emissions reduction might simultaneously be satisfied in some future applications. But tomorrow must wait for a while. Programs such as those being carried out today by the International Flame Research Foundation, by the Department of Energy, by the Gas Research Institute and others, are improving our understanding and leading us "forward to the past," to better use of the traditional gaseous fuels. Author's Biographical Sketch James G. Seebold gained three degrees in Mechanical Engineering at Stanford University. With Chevron Corporation, Jim has for more than twenty years had consulting responsibilities in the general area of combustion and fuels, with a special interest in the fluid mechanics and emissions of combustion. Seebold's videotape course "Refinery Combustion Systems", produced for the Stanford University Industrial Television Network, has been viewed worldwide. He has served as a technical advisor on the United States Department of Energy's Study of Oxygen Enriched Combustion and the United States Environmental Protection Agency's Study of the Efficiency of Industrial Flares, and has served for many years as Chevron's member of the American Flame Research Committee of the International Flame Research Foundation. |