Development and application of multi-field coupling test system for coal-bed methane(CBM) exploitation

Multi-field coupling test system for coal-bed methane(CBM) exploitation was developed independently, which mainly consists of bearing skeleton frame, specimen box, servo loading system, single tube system for methane exploitation, lateral multi-tube system for methane exploitation, and data acquisition system. The test system could be used for multi-field coupling simulation of CBM exploitation under single coal bed occurrence status and multi-coal bed occurrence status, and for multi-field coupling simulation of gas drainage in the distressed area of the protected seam. And multi-channel data acquisition system was used to collect reservoir parameter such as temperature, stress and gas pressure, in order to research their evolution and correlation with gas flow during CBM exploitation. The preliminary result of the CBM exploitation test indicates that: there is obvious coupling effect between gas pressure and temperature, which finds expression in the greater temperature reduction with the greater gas pressure decrease;the difference of gas pressure drop in the section becomes more and more obvious as its distance to the exploitation tube decreases;the pressure and temperature nearby the tube both drop earlier and greater than that of the further location;and the gas pressure gradient is directly correlative with the gas flow. The research proved the test system's qualification and its real-time monitoring function for physical simulation of CBM exploitation. The test system provides a new methodology for research on CBM exploitation by physical simulation. ©, 2014, Academia Sinica. All right reserved.