Research And Application Of Gas Wetting Reversal Method To Increase Coal Bed Methane Recovery

In this paper, throught theoretical analysis and experimental studies, the author measured the porosity, permeability, wettability and heterogeneity of the coal samples from Pingmei Group, and developed the gas wetting reversal agent for the target area, then summarized the main factors which lead the low recovery. On the base of the above study, the author found out a technology to increase the recovery factor of CBM.The main research findings of this paper include the following aspects:1) Summarize the methods and techniques to enhance gas drainage efficiency and extraction rate. On the basis of extensive literature survey, analyzes and summarizes existing theories and techniques of the CBM to further clarify the research orientation.2) Measure the porosity and permeability of the coal sample from the target mining area in different vertical depth, by the methods of gas measured porosity and fluid measured porosity. It can be seen from the results the porosity of coal samples is generally less than5%, and the permeability is mostly lower than0.1mD.3) Study the heterogeneity of the target mining area. Observe; analyze the images taken by scanning electron microscopy, and compare with other domestic and foreign coal seam SEM images.4) Study the wettability of coal samples and development gas wetting reversal agent. Treating coal samples by the developed reversal agent compare the wettability changes and choose the right gas wetting reversal agent for the target mining.5) Research and analyze the fracturing technology for occurrence coal seam. Analyze the CBM extraction effect after the fracturing of the target mining area.