Simulation of Drying and Oxidation Process of Pellets Layers in Steel Belt Sintering

doi:10.12068/j.issn.1005-3026.2021.09.010

Abstract

Abstract: A multi-scale Eulerian-Eulerian mathematical model was developed to study the drying and coke-magnetite oxidation process of ferrochrome pellets in a steel belt sintering machine. Physicochemical reactions of an individual pellet were calculated by the shrinking core model. The predictions were in reasonable agreement with the industrial data. The results showed that the drying of green pellets can be divided into two stages: the uneven increasing-rate and the falling-rate drying stages. However， in the latter stage， it was also observed that the drying rate increased gradually at the bottom of green pellets when the surface temperature of the wet bulb was higher than 383K. It decreased again after the radius of the wet bulb was smaller than 4.75mm. The maximum weight percent of the moisture in green pellets was 10.2%， which was 7.4% higher than the initial one. When the temperature of ferrochrome pellets reached the coke ignition， the coke oxidation had precedence over the magnetite oxidation. The average sintering temperature of green pellets was 1698K at the outlet of the sintering zone， meeting the process requirements.

Key words: sintering of ferrochrome pellets; shrinking core model; heat and mass transfer; drying and oxidation

CLC Number:

TF046

WANG Chang-jun， YU Yang， LI Bao-kuan， LIU Xue-lin. Simulation of Drying and Oxidation Process of Pellets Layers in Steel Belt Sintering[J]. Journal of Northeastern University(Natural Science), 2021, 42(9): 1282-1289.

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