Development of novel 100 kW microwave-assisted rock excavation system for large scale proof-of-concept

采矿业的未来被认为是连续、自动化、实时监测和控制、一致的产品、高效、节约能源和减少环境足迹。目前，大多数开采过程都是采用钻爆技术进行分批开采，一些软岩和煤矿开始采用连续采煤机、采煤机等岩石切削工具进行连续开采。然而，在硬岩矿山中，由于机械切削齿钻入率低、机械工具磨损大、设备尺寸不实用（如果在地下矿山中）、工具能耗大等原因，连续开采方法仍然面临着许多挑战，效率远不高。从2008年开始，我们的团队探索了各种可能的使用无炸药破岩技术的连续开采方法。结果表明，微波辐照结合机械切削工具对岩石进行预处理（弱化）是最可行的方法。这一结论引起了矿业公司的注意，并在2011年至2016年（第二阶段）获得了NSERC合作研究与开发（CRD）资助。论证了影响岩样辐照的基本参数及其对岩石强度降低的影响。研究并证明了微波辅助破岩技术在开挖中的可行性。此外，之前的NSERC CRD拨款使申请人能够建造最先进的15千瓦微波辅助岩石破碎试验台，这是加拿大麦吉尔大学独有的，也是世界上为数不多的。目前，我们的岩石微波研究已进入第三阶段。由矿业公司支持的NSERC合作研究与开发（CRD）赠款正在进行中。第三阶段的目标是进行大规模的现场试验，以证明微波辅助岩石开挖工具的概念。通过NSERC RTI要求的设备是一个100千瓦的岩石微波系统，以升级我们现有的15千瓦岩石微波系统。请注意，我们现有的15千瓦岩石微波系统已成功用于实验室规模的概念验证；然而，对于大规模的现场试验，需要更强的100 kW的微波辐照功率，即岩石在采煤台阶或采煤工作面中较大且自然受限，以及实际开采环境下岩石颗粒组成非均质性的随机性，再加上岩石切削工具设备。

The future of mining industry is believed to be continuous, automated, real-time monitoring and control, consistent product, efficient, conserve energy and reduce environmental footprint. Currently, most of mining process are in batch mode using drill and blast technique, albeit some soft-rock and coal mines started implementing continuous mining method using continuous miner, shearer and other rock cutting tools. In hard-rock mine, however, continuous mining method still faces many challenges and far from efficient due to low penetration rate of mechanical cutters, high wear of mechanical tools, unpractical size of equipment (if it is in underground mines) and high energy consumption of the tools. Started in 2008, our team has explored various possible method of continuous mining using explosive free rock breaking techniques. It was concluded that the most feasible technique to pre-condition (weaken) the rock using microwave irradiation coupled with mechanical rock cutting tool. This conclusion drew the attention of mining companies and resulted in securing an NSERC Collaborative Research and Development (CRD) grant in 2011 – 2016 (Phase II). Basic parameters affecting the irradiation of rocks samples and its influence on the reduction of rock strength has been demonstrated. This study investigated and proved the feasibility of using microwave-assisted rock breaking technology in excavation. Also, this previous NSERC CRD grant enabled the applicants to build a state-of-the-art 15 kW microwave-assisted rock breakage test rig, unique to McGill University in Canada and one of the few in the world. Currently, our rock-microwave research is entering Phase III. NSERC Collaborative Research and Development (CRD) grant supported by mining companies is underway. The objective of Phase III is large scale in-field tests for proof of concept of microwave assisted rock excavation tool. The equipment requested through NSERC RTI is a 100 kW rock-microwave system to upgrade our existing 15 kW rock-microwave system. Note that our existing 15 kW rock-microwave system was successfully used for lab-scale proof of concept; however, stronger microwave irradiation power of 100 kW is essential for large scale in-field tests, i.e. rocks are much larger and confined naturally in the mining bench or mining face as well as the stochastic nature of the heterogeneity of rock particles composition under real mining environment coupled with rock cutting tool equipment.