利用排采数据校正煤层含气量

目前,国内外煤层含气量最常用的测定方法为取芯做解吸实验,逸散气量利用直接法由解吸时间确定。然而在此过程中,最容易引起误差的部分即逸散气量的估算;尤其是取芯时逸散时间未能控制在标准时间内;或者计算含气量时逸散气量没有得到正确校正,都会导致所得含气量结果产生较大误差,从而误导产能评估、开发设计和生产控制。采用逆向思维,利用排采数据求取每口井的产气压力;并与由实验室所测数据和朗格缪尔方程求取的临界解吸压力相对应,求得对应煤层的含气量;然后利用数理统计方法曲线回归建立含气量与深度的函数关系式,进而计算所有煤层含气量,以指导后期的优化、开发和生产。

Gas content calibration through production data

The most reliable gas content method is coring,then measure gas desorbed from coal samples in a canister. However, the greatest errors in estimating total gas content in this way are usually caused by errors in the lost gas volume estimation, especially when lost gas volume is not involved in the total gas estimation. How to calibrate gas content when the provided data even does not include lost gas estimation is still a problem. In this study, new idea on gas content verification will be mentioned through production data from which critical desorption pressure, relationship between gas content and depth will be derived from production data which can be used to compute gas content of each coal seam.