Studying the Effect of Grinding Mechanism and Composition of Golgohar Concentrate on the Microstructure and Mechanical Properties of Pellets

Document Type : Original Articles

Authors

Abouzar Eskandarinasab ¹

Abouzar Eskandari Nasab ²

Gholamhossein Akbari Fakhrabadi ²

¹ Department of Materials Science and Engineering, Shahid Bahonar University of Kerman, Kerman, Iran.

² Department of Materials and Metallurgy Engineering, Shahid Bahonar University of Kerman, Kerman, Iran

10.22067/jmme.2025.90387.1162

Abstract

The effect of raw material composition and grinding process by ball mill and HPGR in Golgohar Complex on the properties of the final pellet was investigated. Tests were performed on the mixer input feed in the form of raw material composition analysis, granulation, moisture content and specific surface area measurement using two methods, Blaine and BET. Also, strength measurement and microstructural analysis were performed using SEM on raw and cooked pellets. In addition, the abrasion resistance and sphericity of the pellets were investigated. The results of the tests showed that the particle size produced by the ball mill was finer and had a higher specific surface area (1988 cm2/g). The morphology of the particles produced by the two milling methods was irregular and non-spherical and did not differ significantly from each other. The input feed of the pelletizing plant number one had a higher percentage of FeO, sulfur, and magnesium oxide. Also, microstructural studies of the pellets indicate a better distribution of fine particles and non-magnetic phases in the pellets produced in Plant No. 1. The pellets produced in Plant No. 1 have higher wet strength (WCS), while the dry strength (DCS) and fired strength (CCS) of the pellets produced in Plant No. 2 are higher. In addition, 96.3% of the pellets from the plant number one passed the dumpler abrasion test without crushing, and their sphericity was 0.824, which was higher than that of the pellets produced by the HPGR method.

Keywords

Pellets

Iron recovery

HPGR

Magnetite

Granulation

Subjects

• Extractive Metallurgy

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