Water Infusion
Control 0 CommentWater Infusion Water infusion, the injection of water at high pressure (>7 Mpa), has been explored as a stress relief mechanism to prevent outbursts. The water pressure fractures the coal in advance of the face and provides for slow relaxation of stress through lateral movement enhanced by the presence of […]
Read MoreGround Destressing
Control 0 CommentGround Destressing Two of the key elements associated with outbursts are mine gases and tectonics. Just as gas drainage involves the prevention of outbursts in the seam and or associated rock strata to prevent outbursts. Currently, there are four different mechanisms used to de-stress a seam outburst prevention, these being […]
Read MorePulse Infusion Shotfiring
Control 0 CommentPulse Infusion Shotfiring Inducer shotfiring is considered to be the oldest and most widely used method to control outbursts in mines, and it was initially developed in France by the end of 19th or beginning of the 20th Centuary in the Gard coalfield. Blast holes are drilled into the face […]
Read MoreHydraulic Fracturing
Control 0 CommentHydraulic fracturing has been used by the mining industry at least since the end of the 19th century, when it was applied to quarrying blocks of granite, and in the petroleum industry since the late 1940s when it was introduced to stimulate wells. It now represents a major petroleum service […]
Read MoreGas Drainage
Prevention 0 CommentRemoval of gas from the coal seam and surrounding strata has proven to be an effective method in reducing or eliminating outbursts. The benefits of gas drainage are: Gas given off from the virgin coal is reduced so that gas percentage in intake airways and at working faces are kept […]
Read MoreGas Threshold Limits
Prevention 0 CommentIn 1994 and following a fatality at West Cliff Colliery relating to an outburst incident, a notice under section 61 of the Coal Mines Regulation Act, 1982 was issued to all mines operating in the Bulli seam. This notice enforced gas threshold values on these mines to the extent that […]
Read MoreGeophysical detection of outbursts
Prediction 0 CommentGeophysical techniques provide the opportunity for remote assessment of the state of a rock mass and to remotely monitor changes in its behaviour. Geophysical techniques are widely used for these purposes in resource exploration and extraction. Because coal outbursts can be associated with geological structures and with zones of anomalous […]
Read MoreMonitoring
Prediction 0 CommentGas Monitoring System The gas monitoring systems widely used in Australian underground mines are: Tube Bundel System ( ACARP report C 3076) Telemetry System ( ACARP report C 3076) Advantages of Tube Bundel System Disadvantages of Tube Bundel system Continious monitoring Monitoring of full range of gases Sometimes difficult to locate […]
Read MorePrediction Indices
Prediction 0 CommentOutburst prediction indices( ACARP C 4034 Chapter 9) Different indices are use in different countries to predict an outburst Ettinger’s Sorption/ Desorption index : This index was developed initially by Ettinger (1953) as the means of classifying coal in terms of proneness to outburst. The gas emission index was based on the gas pressure […]
Read MoreGeology
Prediction 0 CommentGeology plays a very important role in the manifestation of Outbursts. Seams having complex geological structures are more prone to outbursts if high gas conditions are prevalent. The following points need attention when geological factors are being considered. • Any structure related to horizontal movement of beds within the coal […]
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