水平气井斜井段气流携液分析研究

Analysis and Research on Air Flow and Liquid Carrying in Inclined Section of Horizontal Gas Well

水平气井斜井段气流携液最为困难,气流携液状况较为复杂,现有携液模型不够准确。鉴于此,本文利用室内多相管流实验及理论分析相结合的方法,针对斜井段气流携液开展了特定研究。研究发现,斜井段气流携液处于段塞流向扰动流转变的临界状态;井筒中持液率随产气量的减小而增大,随管倾角的增加而呈现先增大后减小的趋势;建立的斜井段临界新模型经现场验证,其预测准确度高,平均误差小(2.16%)。本文的研究可为水平气井实施排液采气工艺措施提供科学依据,为实际生产过程提供一定的理论参考。

It is the most difficult for the air flow to carry liquid in the inclined section of a horizontal gas well. The air flow and liquid carrying situation are more complicated, and the existing liquid carrying model is not accurate enough. In view of this, this paper uses the method of indoor multiphase pipe flow experiment and theoretical analysis to carry out specific research on air flow and liquid carrying in the inclined well section. The study found that the gas flow in the inclined well section is in the critical state of the transition from slug flow to disturbance flow;the liquid holdup in the wellbore increases with the decrease of gas production, and shows a trend of first increasing and then decreasing with the increase of pipe dip.;the new model for criticality of the inclined well section has been verified on site, and its prediction accuracy is high, and the average error is small (2.16%). The research in this paper can provide a scientific basis for the implementation of liquid drainage and gas recovery technology measures in horizontal gas wells, and provide a certain theoretical reference for the actual production process.