The mining industry has many facets, which may be grouped as :-
- the mine facility, which is basically the geological environment and the physical structure of the mine, be it underground or surface mining;
- the mine machinery, which, while utilising different machines for underground and surface operations, have similar applications,
- product preparation, which includes washing and grading of the final product.
Acoustic emission techniques have direct applications in each of these areas. Metacoustics has completed a number of major research projects with the mining industry in each of the above groupings. It has been demonstrated that surface monitoring of underground mining can detect the earliest rock deformation in a mine roof, and, with local knowledge, warning can be given prior to a roof fall, goaf activity, or product seam collapse. Using acoustic emission and micro-seismic techniques, Metacoustics has developed a mine specific monitoring technology which uses the natural world wide earth tide stimulus to provide the energy to monitor mine roof activity.
The continued damage to mine machinery is an ongoing cost to mine operators. Metacoustics has been active in researching these problems in the mining industry and has recently completed nine years of active research on mining machines, with specific reference to draglines. The Metacoustics instrumentation was installed on operating draglines for this period and was still operational and in calibration at the end of the nine years. Metacoustics has adapted this technology into a long term, remote surveillance system that can be applied to most mine machinery.
Metacoustics has also developed technology based on acoustic emission techniques that can quantify ash content of coal, virtually in an on-line situation.