NMRI research of storage and transport of coal bed methane

Nuclear Magnetic Resonance Imaging, called NMRI for short, is an advanced non-damaged test method. NMRI method was introduced into the study of coal bed methane. The three-axis stress osmo-scope was designed originally which can be placed into NMRI equipment. The adsorption, desorption and diffusion of coal bed methane in coal seam were studied in microcosmic field by NMRI. The quantitative analysis of physics and mechanics parameters of pore structure and coal permeability and so on can be done with it. Using NMRI the whole processes of desorption, diffusion and seepage of coal bed methane can be explained on basis of microcosmic field. The imaging mechanism and application in coal bed methane were presented. It is indicated that permeability of coal seam, as an important parameter that shows the transport rule of coal bed methane, has basic correlation with NMR permeability. The calculation method of NMR permeability was put forward. The results show that the quantitative analysis and real-time observation of the storage and transport of coal bed methane by NMRI are more effective and accurate. So NMRI research of the storage and transport of coal bed methane supplies new means and approach to increase the recovery ratio of coal bed methane that will plays important roles in site practice in China.