从煤层含气量测定技术发展看页岩含气性评价的发展方向

Prospect of shale gas evaluation in view of measurement techniques development of coal seam gas content

鲍云杰

Bao Yunjie

中国石化 石油勘探开发研究院 无锡石油地质研究所, 江苏 无锡 214151

Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi, Jiangsu 214151, China

介绍了煤层含气量测定技术的发展历程,以及煤心中甲烷的逸散、解吸模拟实验研究成果,剖析了现用煤层含气量测定标准的适用范围及其约束条件。指出页岩岩心在提心、大气暴露和密封解吸三个阶段具有不同的气体逸散、解吸条件和机制,煤心损失气量估算方法应用于页岩存在着不确定性和风险。提出应重视页岩岩心涵盖"三个阶段"的全过程气体逸散、解吸实验及其规律的基础性研究。将页岩气分为钻井液气、暴露散失气和岩心残留气三部分。开发钻井液气检测装置,结合综合录井资料,建立钻井液气量的快速检测技术及计算方法;完善现有岩心解吸气和残余气测定技术,形成岩心残留气量快速测定方法;探索建立探测或利用解吸气测试数据确定暴露散失气量的方法,从而构建新的页岩含气量测定技术方法体系。

It was introduced in this paper the development process of coal seam gas content measurement techniques, the experimental modeling results of methane escaping and desorption in coal cores, as well as the application conditions and constraints for the present coal seam gas content measurement standards. During the sampling, atmospheric exposure and sealing desorption phases of coal cores, the conditions and mechanisms for gas escaping and desorption were various. Uncertainty and risk remained when coal core gas loss estimation method was applied in shales. The basic studies of gas escaping and desorption in shale cores during the above-mentioned three phases should be focused on. Shale gas was classified into three types: gas in drilling fluids, gas exposed and escaped, and gas remained in cores. Some proposals were made as followed to set up a new measurement techniques standard of gas content in shales: developing detection devices for gas in drilling fluids, and establishing rapid detection and calculation methods for gas in drilling fluids combined with comprehensive logging data; improving the existing core desorption gas and residual gas measurement technology, and establishing a rapid determination method for core residual gas; exploring for the detection or calculation method for exposed and escaped gas based on desorbed gas tests.

https://doi.org/10.11781/sysydz201406762