Luo Pan, Harrist Jonathan, Menduni Giansergio, Mesdour Rabah, StMichel Nathan, Sampaolo Angelo
EXPEC Advanced Research Center, Saudi Aramco, Dhahran 31311, Saudi Arabia.
Houston Research Center, Aramco Americas, Houston, Texas 77084, United States.
ACS Omega. 2022 Jan 18;7(4):3395-3406. doi: 10.1021/acsomega.1c05645. eCollection 2022 Feb 1.
Natural gas is sampled and produced throughout the lifespan of a petroleum field. Gas composition and isotope data are critical inputs in the exploration and field development, such as gas show identification, petroleum system analysis, fluid characterization, and production monitoring. On-site gas analysis is usually conducted within a mud gas unit, which is operationally unavailable after drilling. Gas samples need to be taken from the field and shipped back to the laboratory for gas chromatography and isotope-ratio mass spectrometry analyses. Results are usually without sufficient resolution to fully characterize the heterogeneity and dynamics of fluids within the reservoir and the production system. In addition, it often takes a considerable time to obtain the results using the traditional method. A novel QEPAS (quartz-enhanced photoacoustic spectroscopy) sensor system was developed to move gas composition analyses to field for quasi-real-time characterization and monitoring. With respect to previously reported QEPAS prototypes for trace gas detection, the new system realized measuring concentrations of methane (C1), ethane (C2), and propane (C3) in gas phase within the percentage range that is typically encountered in natural gas samples from oil and gas fields. A gas mixing enclosure was used to dilute the natural gas-like mixtures in nitrogen gas (N) to avoid the saturation of QEPAS signals. An iterative analysis based on multilinear regression of QEPAS spectra was developed to filter out the influence of gas matrix variation from multiple hydrocarbon components. The advance in simultaneous measuring hydrocarbon gases and expanded linearity range of QEPAS, with previously reported detection of HS, CO, and gas isotopes (CO/CO, CH/CH), opens a way to use the advanced sensing technology for in situ and real-time gas detection and chemical analysis in the oil industry.
在石油田的整个生命周期内都会对天然气进行采样和生产。气体成分和同位素数据是勘探和油田开发中的关键输入信息，例如气测显示识别、石油系统分析、流体表征以及生产监测等。现场气体分析通常在泥浆气单元内进行，而该单元在钻井后就无法运行了。需要从现场采集气体样本并运回实验室进行气相色谱和同位素比率质谱分析。其结果通常分辨率不足，无法充分表征储层和生产系统内流体的非均质性和动态变化。此外，使用传统方法往往需要相当长的时间才能获得结果。一种新型的石英增强光声光谱（QEPAS）传感器系统被开发出来，以便将气体成分分析转移到现场，实现准实时表征和监测。相对于先前报道的用于痕量气体检测的QEPAS原型，新系统能够在油气田天然气样本中常见的百分比范围内测量气相中的甲烷（C1）、乙烷（C2）和丙烷（C3）浓度。使用气体混合箱将类似天然气的混合物在氮气（N）中稀释，以避免QEPAS信号饱和。基于QEPAS光谱的多线性回归开发了一种迭代分析方法，以滤除多种碳氢化合物成分引起的气体基质变化的影响。QEPAS在同时测量碳氢化合物气体方面的进展以及线性范围的扩大，加上先前报道的对H₂S、CO和气体同位素（¹³CO/¹²CO、¹³CH₄/¹²CH₄）的检测，为在石油工业中使用先进传感技术进行原位实时气体检测和化学分析开辟了道路。
