Monash University’s Geo-mechanics for Geo-energy and Geo-resources Deep Research Group (or 3GDeep) consists of ten key researchers and well over 30 PhD students. 3GDeep’s primary aim is to facilitate collaborative research – fundamental and applied research on feasibility assessment, and on technical problems in the development of alternative deep-Earth resources. These include new low-emission hydrocarbon alternatives (such as underground coal gasification, coal-bed methane, shale gas, and tight gas and oil); renewable energy sources (geothermal energy); options for geological waste containment, notably carbon dioxide (CO2) storage and nuclear waste disposal; and future metals that will be critical for renewable energy technologies.

The group’s research laboratory (3GDeep-RL) has state-of-the-art testing facilities. 3GDeep-RL is the first of its kind in Australia and Worldwide, and serves as a national focal point for this specialisation. Its suite of equipment (valued at A$18 million, featuring macroscale high-pressure testing chambers) is unique in Australia and perhaps the world. Through 3GDeep-RL, Monash has drawn international attention as a power house for large-scale testing applied to deep-Earth explorations. These advanced facilities enable unprecedented research on coal-seam gas, shale gas, oil, and deep geothermal recovery under complex and extreme geological conditions.

Climate change legislation, along with regulations to limit greenhouse gases, has led to natural gas competing with oil and coal. It now ranks as the third largest of the world’s energy sources. Among these sources, natural gas is the cleanest and most hydrocarbon-rich, with high energy-conversion efficiencies for power generation. The greatest challenge to its exploitation is very low recovery of gas. Because of extremely low permeability in shale gas reservoirs, adequate recovery demands permeability-enhancing techniques. Of all these techniques, hydraulic fracturing (hydro-fracturing) of the reservoir rock by injection of high-pressure fluid is the most commonly used. However, conventional enhancement of permeability for hydro-fracturing poses significant environmental challenges; so we are developing environmentally friendly extraction techniques, through critical experiments in modified hydraulic fracturing. These innovative techniques (especially use of waste CO2 as an input to the unconventional reservoirs) need hard research to identify optimum mechanisms with rigour and certainty.

CO2 emissions into the atmosphere (mainly from use of fossil fuel in power generation and other industrial processes) can be reduced by as much as 90 per cent, through carbon capture and storage (CCS). CCS is widely considered the best large-scale option for mitigating climate change. However, predicting the long-term safety of CO2 storage in oceans or deep underground is still very difficult. It is a major focus for our team. We work for a future in which deep geological CCS systems are a fully functioning, immediate, and affordable option for controlling the impacts of global warming. According to our findings, injection of nitrogen into the coal seam during sequestration will reverse CO2-induced swelling by 20 or 30 per cent, considerably increasing CO2 injectability; and efficiency will also be improved by proper control of how injection and production wells are arranged. As a further major development, our group has provided first confirmation that supercritical CO2 can significantly reduce permeability in coal seams and similar porous media. This finding opens up new research directions toward the use of supercritical CO2 flow through deep underground reservoirs (coal seams, shale basins, saline aquifers, and oil beds). It also promises important advances in CO2 injection for enhanced recovery of coal-seam gas.

The mining industry seeks innovations in the science and technology of breaking rocks for mineral extractions – to reduce energy consumption through operational efficiencies, and to minimise environmental impacts. Our group researches and develops innovative techniques for rock fragmentation: primarily at mine sites, but also for later comminution of extracted materials. We envisage significantly less consumption of energy in processing. Given Australia’s pre-eminence in this domain and its excessive expenditure on energy, the national benefit alone will be significant (saving of billions of dollars every year), even before considering the global impact. Techniques developed in recent decades have failed to improve the situation; but our team has radical new methods in mind.

 

 3GDeep Group Members (not all members in the photo)

 

Prof Ranjith PG
Founding Director of 3GDeep Research Group
Head, Geomechanics