Modelling of Gas Flow in Fractured Rock and Coal
Methane (CH4) forms a significant component of coal seam gas and is extracted as a preventative measure before or during the mining of coal，as well as for a resource in its own right.Aspart of a major collaborative project with the aim of extracting gasses for low-emission energy from deep or otherwise difficult seams，an explicit fracture computer model of coal seam methane extraction is being developed.The aim of the model is to assist and verify the continuousmodels in predicting the rate of coal gas extraction by simulating the deformation of coal andthe flow of gas through fractures and natural joints.Initial studies to investigate theinfluence on computer run times of fluid and material properties and the ratio of mechanical to fluid cycles in the computer program are presented.The paper then presents initial results from a multi-seam model of coal.Results indicate that extraction of methane into a borehole changes the local pore pressure distribution leading to shrinkage of the coal while injection of fluid into a borehole inhibits this deformation.With two coal seams separated by five metres，themodelling results indicate that methane extraction is enhanced if fluid is injected into theborehole in the adjacent seam in comparison with the case of extracting gas from both holessimultaneously.These results，while still preliminary，offer the potential to optimise theextraction of coal seam gas by developing optimal staged injection and extraction scenarios.
Coal Methane Numerical modelling Joint fluid flow
Brett Poulsen Baotang Shen
CSIRO Exploration&Mining,PO Box 883 Kenmore,Queensland 4069 Australia
国内会议
安徽淮南
英文
178-190
2007-10-25（万方平台首次上网日期，不代表论文的发表时间）