Development of novel technologies for predicting and combating gas outbursts and uncontrolled emissions in thick seam coal mining (COGasOUT) : final report

The main objective of this project has been to develop and test new and novel technologies for the assessment, prediction, prevention and risk management of gas outbursts and uncontrolled gas emissions in coal mines which operate in thick and/or steeply dipping thick seams. The project monitored stress and gas dynamics in the seams around the longwall faces as well as monitoring gas emissions and concentration in the ventilation air in the test districts. The application of seismic tomography as the means to detect changes in lithology, structural features and stress/gas pressure zones ass an indicator of outbursts were investigated. Remote and automated microseismic monitoring of the processes leading to outburst and/or uncontrolled gas emissions at Coal Mine Velenje and HVL lead to the development of a methodology to identify the building up of excessive gas emissions and outburst conditions. The use of advanced electromagnetic survey techniques for detection and characterisation of overstressed zones and other geological stress anomalies which lead to gas outburst conditions was also invstigated. Coupled geomechanical and gas flow simulations of realistic mining layouts successfully history matched field measurements. An outburst model to assist the analysis and assessment of stress, gas pressure and permeability conditions leading to gas outbursts was developed. The drainage trials at Coal Mine Velenje were successfully completed. Drainage trials at HVL were not as successful due to malfunctioning of the drainage system. Numerical predictions of the drainage trials matched the exact location of low/high permeability and successful drainage locations around LTCC faces. A risk assessment framework and a methodology for outburst was developed and validated using data obtained at HVL. MRSL developed the prototype outburst protective barrier, evaluated its functioning principles in test galleries and provided realistic designs for its application underground.