The influence of microwave irradiation on thermal properties of main rock-forming minerals. (5th February 2017)

• Record Type: Journal Article
• Authors: Lu, Gao-ming; Li, Yuan-hui; Hassani, Ferri; Zhang, Xiwei
• Is Part Of: Applied thermal engineering. Volume 112(2017:Feb.)
• Page Start: 1523
• Page End: 1532
• Publication Date: 2017-02-05
• Subjects: Thermal stress -- Thermal expansion -- Microwave-assisted rock fragmentation -- Rock-forming minerals -- Microwave absorption capacity -- SEM-EDX elemental analysis; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2016.11.015
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: Different rock-forming minerals present very different microwave absorption capacity to microwave energy. The test results can be used to estimate the heating behaviors of rocks to microwave irradiation. SEM-EDX technique was used to determine the elemental distribution and mineralogical composition. Ferrum may influence the interacting mechanisms between rock-forming minerals and microwaves. Abstract: The sample will burst into fragment when the thermal stress induced by thermal expansion greater than the ultimate strength of the rock after microwave irradiation. Microwave-assisted rock fragmentation has been illustrated to be potentially beneficial for mineral processing, mining and geotechnical engineering. In order to have a comprehensive understanding on the influence of microwave on thermo-mechanical properties of rocks, it is necessary to investigate the interaction effect between microwaves and the main rock-forming minerals. In this work, eleven rock-forming minerals were tested in a multimode cavity at 2.45G Hz with a power of 2 kW, subsequently, the Scanning Electron Microscopy–Energy Dispersive X-ray (SEM-EDX) was used to determine the elemental distribution and mineralogical composition of the tested samples. It was observed that different rock-forming minerals present very different susceptibility induced by microwave treatment. Enstatite presents the strongest microwave absorption capacity by a large margin and most of the rock-forming minerals are weak microwave absorbers. It is significant that the results can be used to predict the heating behaviors of rocks subjected to microwave energy. Furthermore, the SEM-EDX elemental analysis demonstrates that the microwave absorption capacity of rock-forming minerals could link to the contribution of the ferrum, which may influence the interacting mechanisms between microwaves and the rock-forming minerals.