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Show 8 5. Conclusion Reducing and direct-flame burner is already being applied to the continuous annealing furnace in iron and steel works. However, the reduction mechanism is still unknown. In this report, it was proved that the air pre-heating and oxygen enrichment improve reducing ability of reduction flame in experiments. The flame temperature rises with both methods and radical species, especially H, O and O H , are increasingly generated. H, which is generated in the high flame temperature region during early to latter stages of combustion, is the predominant reductive radical species in numerical simulation. It is especially important to clarify the behavior of a radical species with steel. Mixing and combustibility of the resulting mixture were especially considered when the burner structure was designed. One problem is that Nox is generated by high local flame temperature and C O is generated by low air ratio combustion. To solve these environmental problems, further investigation is necessary. The reducing and direct-fired heating method adds the reducing function to the heating process, and is a newly developed process. In addition, basic research on the combustion reaction is necessary to develop new combustion technologies other than heating. References 1. Gotou.K, Uemura.M., Hisano,Y, Saita.H. and Kishi,K, Current Advances in Materials and Processes, 7(1994),p.461 2. Hukuda,S. and Abe,M., Kogyo Kanetsu, 23(1986)4,p.25 3. Suzuki.Y, Yabuki.K, Nojima.K., Takashima,K. and Kaminaka,M. Current Advances in Materials and Processes, 12(1989),p1577 4. Suzuki.Y, Yabuki.K, Okada.S., Takeuchi,K. and Nojima.K, Current Advances in Materials and Processes, 15(1992),p1548 5. Suzuki.Y, Yabuki.K and Okada,S., Current Advances in Materials and Processes, 15(1992),p1549 6. lshibashi,K and Tsuge.S., Tetsu-to-Hagane, 76(1990),p345 |