Comparison of preconditioning rock samples in single and multi-mode microwave cavities for application in comminution processes

Ghoreishi-Madiseha, Shadi, Rafezi, Sasmito, Manouchehri, Hassani

Published in Proceedings of the IMPC2020 Congress, SAIMM


Weakening rocks by taking advantage of microwave-induced microcracks is a promising solution for comminution processes. This paper investigates the effects of microwave treatment of the rock/or samples in single and multi-mode cavities.

Based on the experimental results of using a 2.45 GHz microwave generator, the performance of different cavity setups and their impact on the energy effectiveness of the microwave irradiation was examined. Physical interpretations were drawn from multiple experiments with a relatively wide range of power rates and exposure times. Both basalt and kimberlite samples were used in experiments, and their results were systematically compared.

For single-mode cavity tests, a microwave applicator waveguide antenna was placed at different distances from the samples to evaluate the effects of sample positioning on microwave heating, both numerically and experimentally.

Eventually, cavity performance was assessed by using calorimetric test results, and strength decay was documented based on the spallation of the samples. It was found that the single-mode cavity setup has unique properties that can significantly improve the electromagnetic heating and therefore, strength degradation process.


Microwave, fragmentation, energy effectiveness, calorimetry, mine-to-mill


the financial support of the Natural Sciences and Engineering Research Council of Canada (NSERC) together with our industrial partners DeBeers, Metso, and Argex Titanium Inc. is acknowledged. The authors are also grateful to the staff, engineers, and geologists from these companies for their help and contribution.


S.A. Ghoreishi-Madiseha,*, A.Shadic, H.Rafezib, A.P. Sasmitob, H.R.Manouchehric, and F.P. Hassanib

aCanada Research Chair in Advanced Mine Energy Systems, The University of British Columbia, Vancouver, British Columbia, Canada

bMining and Materials Engineering Department, McGill University, Montreal, Quebec, Canada

cThe University of British Columbia, Vancouver, British Columbia, Canada

* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

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