低渗透油藏CO2驱SF6微量气体示踪实验研究

摘要

The CO2 flooding technology is an effective method for enhanced oil recovery (EOR). Well-to-well tracer test is one important means to achieve the in-depth understanding on the characteristics of the displacement process for CO2 flooding. In this paper, the laboratory study of the SF6 gas tracer test in CO2 flooding is carried out for the natural low permeability core. The micro-size amount SF6 tracer injection method named as "Put in at atmospheric pressure and high-pressure injection" is originally designed, but also the gas chromatography detection method for SF6 tracer is established on the basis of high-sensitivity thermal conductivity detector. The results show that the SF6 tracer delivery process has the advantages of simplicity, controllable dosage strengths and tracer detection method also exhibit the advantages of simplicity, fast detection speed, high sensitivity and good precision.%CO2驱油技术是提高低渗透油藏采收率的有效方法,而井间示踪监测是深入理解实际油田注CO2驱替特征的重要手段之一.通过天然低渗透岩芯CO2驱SF6气体示踪室内实验研究,独创性地设计了“常压加剂高压注入”的微体积量气体示踪剂的投放方法,建立了基于高灵敏度热导检测器的SF6示踪剂气相色谱检测方法.实验结果表明:SF6气体示踪剂的投放工艺具有简便、加剂量可控的优点,示踪剂检测方法具有简单、速度快(2min/样)、灵敏度高(检测极限10-7)和精密度好(相对标准偏差为0.6％)的优点.