STUDY OF THE OXIDATION PROCESS IN IRON–ORE MATERIALS AT TEMPERATE AND HIGH TEMPERATURES
https://doi.org/10.17073/0368-0797-2016-6-378-384
Abstract
The process of oxidation of magnetite and titanium-magnetite in lumped iron-ore materials at temperate (400 – 1000 °C) and high (1000 – 1300 °C) temperatures was studied by using methods of physical-chemical analysis. Kinetics of the diffusion process was studied on briquettes of Olhov and Kachkanar titanium-magnetite concentrate and also on the samples of non-fluxed and fluxed to the basicity 1.3 iron-ore Kachkanar pellets. It was determined that at temperate temperatures the diffusion of reagent is the limiting point of the oxidation process on the zones of spherical surface the size of which is smaller than the total surface of the spherical object. At high temperatures diffusion of oxygen in the pores of pellets is the limiting point of the process in the isothermal and nonisothermal conditions as well. According to kinetic dependence the isothermal oxidation of investigated materials, the apparent energy of activation at the set degrees of conversion was calculated, and changing of the activation is connected with transformation of the type of diffusion of reagents through the layer of the reaction product. The apparent coefficients of diffusion of oxygen applied to iron-fluxed Kachkanar pellets for temperature 500 – 1000 °C were defined. The methods of definition of the oxidation degree of pellets were obtained in dependence on changing time and temperature at nonisothermal operational parameters. The possibility of using the given methods for calculation of the oxidation degree of pellets at their roasting in the conveyer roasting machinery was shown. The obtained results can be used for definition of the completing degree of oxidizing processes in the roasting layer of pellets and at optimizing of operational parameters in roasting machinery.
Keywords
oxidation,
magnetite,
titanium-magnetite,
briquette,
pellets,
analysis,
diffusion,
kinetics,
methods,
operational parameters
About the Authors
S. G. Melamud
Ural Federal University named after the first President of Russia B.N. Yeltsin, Ekaterinburg, Russia
Russian Federation
Russian Federation
Cand. Sci. (Eng.), Deputy Director of Training and Design Center “URFU Design Institute”
B. P. Yur’ev
Ural Federal University named after the first President of Russia B.N. Yeltsin, Ekaterinburg, Russia
Russian Federation
Russian Federation
Cand. Sci. (Eng.), Assist. Professor of the Chair “Thermal Physics and Informatics in Metallurgy”
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Review
For citations:
Melamud S.G., Yur’ev B.P. STUDY OF THE OXIDATION PROCESS IN IRON–ORE MATERIALS AT TEMPERATE AND HIGH TEMPERATURES. Izvestiya. Ferrous Metallurgy. 2016;59(6):378-384. (In Russ.) https://doi.org/10.17073/0368-0797-2016-6-378-384
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