Reduction flame - Kangenen

It refers to a flame with reducing properties, or the reducing part inside a flame. A typical gas burner that premixes air has an inner flame surrounded by a cone that emits a strong blue light, and a large outer flame outside of that. The inside of the inner flame contains unburned gas, N ₂ , CO, carbon, etc., and is reducing, and is called a reducing flame. On the other hand, the outer flame contains high-temperature water vapor, CO ₂ , and oxygen, and is oxidizing, and is called an oxidizing flame. Reducing flame and oxidizing flame are used differently in the bead reaction, a dry analytical method. In industrial heating furnaces, when there is an excess of air, it becomes an oxidizing flame, and when there is an excess of fuel, it becomes a reducing flame. If the purpose is only heating, an oxidizing flame has higher thermal efficiency and is more advantageous, but a reducing flame is also used to keep the atmosphere inside the furnace reducing. [See alternative terms] Flame

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

還元性のある炎，あるいは一つの炎の内部の還元性の部分をいう．空気を予混した通常のガスバーナーには，強い青色の光を放つ円すいで囲まれた内炎と，その外側の大きい外炎とがある．内炎の内部は未燃焼ガス，N₂，CO，炭素などを含み，還元性であり還元炎とよばれる．一方，外炎は高温の水蒸気，CO₂，酸素を含み酸化性であり，酸化炎とよばれる．還元炎と酸化炎は，乾式分析法である溶球反応でそれぞれ使い分けられる．工業用加熱炉では，空気過剰の場合は酸化炎となり，燃料過剰の場合は還元炎となる．加熱だけを目的とする場合は酸化炎のほうが熱効率が高く有利であるが，炉内雰囲気を還元性に保つためには還元炎も用いられる．[別用語参照]火炎

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