Conclusions
The specific rate of additional reduction of the oxides films on the particles of iron in a falling layer of the powder in the temperature range 800–1000°C calculated for the initial specific surface was 0.036–0.078 g[O]/m2· sec. The activation of the reduction process was equal to 54.16 kJ/mole.
The rate of additional reduction of the iron powder in the falling layer is high. For example, in the temperature range 800–1000°C it is 1.2–3.1% [O]/sec.
The experimental results as well as the comparison with the available data make it possible to conclude that the process of reduction of the surface oxides in the falling layer in the temperature range 800–1000°C takes place in the kinetic range of reaction and is limited by the reaction of interaction of hydrogen with the surface oxides of iron.
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Translated from Poroshkovaya Metallurgiya, No. 9-(345), pp. 1–5, September, 1991.
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Maslov, V.A., Aleksandrov, Y.A. Mechanism of additional reduction of metallic powders in a falling layer. Powder Metall Met Ceram 30, 713–716 (1991). https://doi.org/10.1007/BF00794205
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DOI: https://doi.org/10.1007/BF00794205