页岩含气量自动测定技术

由于应用于现场含气量测定的手动排水采气法难以满足页岩储层取样密度增加的需要，为此，研发出页岩含气量自动测定技术。根据在U形管内的液体在同等大气压条件下其液体等高的等压液位平衡原理，采用光电非接触式闭环测控方法，实现对页岩储层含气量的恒压等容自动连续测定。现场应用表明，相邻井深的样品分别采用自动、人工计量方法的测量结果仅相差0.03 m3/t，页岩含气量现场自动测定技术能够代替手动排水采气法，可满足页岩含气量现场测定的需要。该技术能有效减轻现场测试人员的劳动强度，且具有较高的精度，实现了页岩含气量的自动、精准评价。该技术已成功应用于四川盆地20余口页岩气井的含气量现场测定，为四川盆地页岩气示范区（长宁、威远）的建设提供了强有力的数据支撑。此外，该项自动测定技术还能应用于煤层含气量的测定以及气体的连续计量测试。

Automatic shale gas content measurement technology

The manual drainage gas recovery method that is applied to measure the gas content on site can hardly meet the measurement requirements when the sampling density of shale reservoir is increased. In this paper, an automatic shale gas content measurement technology was developed. According to the constant-pressure level equilibrium principle of the liquid of the same height in U-tube under the equal atmospheric pressure, photoelectric non-contacting closed loop measurement and control method is adopted to measure the gas content of shale reservoir automatically and continuously at constant pressure and volume. Field application shows that the difference between the manual measurement and the automatic one of the samples from the adjacent well depth is only 0.03 m3/t. It is indicated that on-site automatic shale gas content measurement technology can take the place of manual drainage gas recovery method and can meet the requirements of on-site shale gas content measurement. By virtue of this technology, the labor intensity of field testers is reduced effectively. This technology is of higher precision and can evaluate shale gas content automatically and precisely. This technology has been successfully applied on site to measure the gas content of over 20 shale gas wells in the Sichuan Basin. It provides the vigorous data support for the construction of shale gas demonstration regions (Changning and Weiyuan) in the Sichuan Basin. This automatic measurement technology can be also applicable to CBM content measurement and continuous gas metering and testing.