Presenting at the Coal Operators Conference 2018

The 2018 Coal Operators Conference is being held on 7-8 February 2018 in Wollongong. The conference, has been held by the Mining and Engineering Group of the Faculty of Engineering and Information Sciences, University of Wollongong, since 1998. The conference is supported by the Illawarra Branch of The Australasian Institute of Mining and Metallurgy (AusIMM) and the Mine Managers Association of Australia (MMAA).

The conference aims to address issues related to various aspects of modern coal mining operations, both surface and underground and offers the opportunity for industry experts to share advice and insights in this area.

Dennis, from CoalGAS, is pleased to be presenting on his recent investigations into the use of the DRI method ( Desorption Rate Index ) to determine outburst threshold limits for Australian underground coal mines. Book your tickets now and come and meet the team.


Title: Analysis of Bulli Seam Benchmark and DRI to determine outburst threshold limits

Abstract: Following the introduction of the Desorption Rate Index (DRI) and Bulli Seam Benchmark to the Australian coal industry in 1995, the use of the DRI900 method was adopted and continues to be used as the primary method to assess outburst risk and to determine gas content threshold values for outburst risk management in Australian coal seams. In addition to assessing outburst risk based on gas content threshold values, several Australian coal mines also include DRI900 as a threshold level in assessing outburst risk. It is apparent that there is a broad lack of awareness and understanding of the limitations and deficiencies of using DRI to assess outburst risk and to determine appropriate outburst threshold limit values.

A comprehensive set of gas test results from Australian coal seams has been collected as part of research into control and management of outburst risk in Australian underground mines and the results of specific investigation into DRI and its applicability for use in assessing outburst risk and determining appropriate gas content threshold levels has identified significant deficiencies which are presented and discussed.

Title: Control and management of outburst in Australian underground coal mines

Abstract: Outbursts represent a major safety hazard to mine personnel working near the coal face in areas of increased outburst risk. There have been over 878 outburst events recorded in twenty two Australian underground coal mines and most outburst have been associated with abnormal geological conditions.

Details of Australian outburst incidents and mining experience in conditions where gas content was above current threshold levels is presented and discussed. Mining experience suggests that for gas content below 9.0 m 3 /t, mining in CO2 rich seam gas conditions does not pose a greater risk of outburst than mining in CH4 rich seam gas conditions.

Mining experience also suggests that where no abnormal geological structures are present, mining in areas with gas content greater than the current accepted threshold levels can be undertaken with no discernible increase in outburst risk.

The current approach to determining gas content threshold limits in Australian mines has been effective in preventing injury from outburst however operational experience suggests the current method is overly conservative and in some cases the threshold limits are low to the point that they provide no significant reduction in outburst risk.

Other factors that affect outburst risk, such as gas pressure, coal toughness and stress and geological structures are presently not incorporated into outburst threshold limits adopted in Australian mines. These factors and the development of an Outburst Risk Index applicable to Australian underground coal mining conditions is the subject of ongoing research.

Find out more about the Coal Operators Conference