Keywords
direct reduced iron (DRI)
catalysis
iron catalyst
swelling
absorption
nitriding
isothermal reduction
nitrogen in coal
How to Cite
Abstract
The purpose of this work is to study the relation and the effect of nitrogen in the reducing gas mixture used in the isothermal reducibility testing of the iron oxide by planning and carrying out using ammonia gas so that its decomposition produces 15% H2 and N2 gases. Ammonia gas also 6% by volume was added to a gas flow containing 28% H2 y 68% N2 by weight so that obtain a final gas composition of 30% H2 and &0% N2. This reinterpretation of the test data allows the comparison of reducibility test reducibility in such a way to compare the nitrogen effect on swelling of iron oxides undergoing reduction. The comparison was made based on the theoretical estimation of nitrogen absorption, the fresh metallic iron formation during the hematite-magnetite-Wustite so produced and the abnormal volume increase of the considered samples. It was also possible to empirically relate and compare the studied effects of nitrogen content from different sources but gas such as solid carbon-containing reducers such as coalThe purpose of this work is to study the relation and the effect of nitrogen in the reducing gas mixture used in the isothermal reducibility testing of the iron oxide by planning and carried out using ammonia gas so that its decomposition produces 15% H2 and N2 gases. Ammonia gas also 6% by volume was added to a gas flow containing 28% H2 y 68% N2 by weight so that obtain a final gas composition of 30% H2 and &0% N2. This reinterpretation of the test data allows the comparison of reducibility test reducibility in such a way to compare the nitrogen effect on swelling of iron oxides undergoing reduction. The comparison was made based on the theoretical estimation of nitrogen absorption, the fresh metallic iron formation during the hematite-magnetite-Wustite so produced and the abnormal volume increase of the considered samples. It was also possible to empirically relate and compare the studied effects of nitrogen content from different sources but gas such as solid carbon-containing reducers such as coal.
Keywords: Gaseous reduction, Direct reduced iron (DRI), catalysis, iron catalyst, swelling, absorption,
nitriding, isothermal reduction, nitrogen in coal.
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