Effect of thermal treatment on phase transformations and standard Bond rod mill work index

Authors

1 M.Sc Graduated, Dept. of Mining Engineering, Imam Khomeini International University

2 Assistant Professor, Dept. of Mining Engineering, Imam Khomeini International University

Abstract

In this study, the effect of thermal treatment on phase transformations and grindability of a low-grade manganese ore containing silica was studied. Thermal analysis (DTA/TG) and scanning electron microscope (SEM) are used to study the phase transformation and structural change of samples under thermal treatment. Thermal effect on grindability under various temperature and thermal duration time on mill feed was determined by standard Bond rod mill work index. Based on the results of thermal analysis, at 750°C dehydroxylation of montmorillonite and decomposition of calcite occured, and at 850°C decomposition of montmorillonite to silicate minerals were proved. SEM studies revealed that thermal treatment lead to some cracks with the size of 280*13 µm in the sample. For 60 min thermal treatment, while increasing temperature to 800°C, the amount of fine particles produced in a cycle (Gi) and the P80 of the mill product were increased to 90% and 10%, respectively and standard Bond rod mill work index was decreased from 20.06 Kwh/t to 14.35 Kwh/t.

Keywords

References

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Journal of Mineral Resources Engineering
Volume 2, Issue 2
September 2017
Pages 33-43

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  • Receive Date: 20 September 2017
  • Accept Date: 20 September 2017

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