泡沫排水采气井筒流动规律实验研究

An Experimental Study of the Flow Characteristics of Foam Drainage Well

王贵生 张宇豪 王志彬 王翔 王锦昌

WANGGuisheng ZHANGYuhao WANGZhibin WANGXiang WANGJinchang

中国石化华北分公司采气一厂, 陕西 榆林 719000 西安交通大学动力工程多相流国家重点实验室, 陕西 西安 710049 油气藏地质及开发工程全国重点实验室·西南石油大学, 四川 成都 610500 中国石化华北分公司工程技术研究院, 河南 郑州 450006

No. 1 Gas Production Plant of North China Branch, SINOPEC, Yulin, Shaanxi 719000, China State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China National Key Laboratory of Oil & Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, China Research Institute of Engineering Technology of North China Branch, SINOPEC, Zhengzhou, Henan 450006, China

泡沫排水采气工艺因成本低、施工简单及收效快在国内外各大气田广泛应用，在众多排水采气工艺中扮演主力军作用。准确揭示泡沫排水井井筒压降规律及携液规律对于优化泡沫排水工艺技术参数、提高泡沫排水采气工艺技术水平具有重要意义。搭建了高8 m、内径30 mm可视化实验装置，通过垂直管流实验对比了起泡剂对气液两相流型特征及流型转化条件的影响，揭示了其内在机理；测试了起泡剂浓度、气相表观流速、液相表观流速和倾角对气液两相压降、持液率和临界携液气相流速的影响规律。实验表明，加入起泡剂后： 1）降低了段塞流向搅动流、搅动流向环状流转变的气相表观流速，使段塞流和搅动流的气相流速区间变窄。2）段塞流和搅动流的压力梯度显著降低，环状流压力梯度显著增加。3）段塞流和环状流气液间的滑脱减弱，持液率降低。4）连续临界携液气相流速急剧降低，在50 °左右的倾斜管段效果尤为明显，最大降幅超过40%。

Foam drainage and gas recovery technology is widely used in various gas fields, especially low permeability gas reservoirs at home and abroad due to its low cost, simple construction and quick results. It plays a leading role in many drainage and gas recovery processes. It is of great significance to accurately reveal the flow pattern and the liquid carrying rule of the bubble discharge well in order to optimize the technological parameters of bubble discharge process and improve the technological level of foam drainage and gas production. Therefore, in this paper, a set of 30 mm diameter visual experimental equipment was set up to carry out the experimental research of surfactant effect on the flow characteristics of gas-liquid twophase flow under different surfactant concentration, inclination angle and gas-liquid ratio. By comparing the flow characteristics with and without surfactant, surfactant effect on flow pattern, structure and transition boundary of gas-liquid two phase flow in vertical pipe were analyzed. The experimental results show that: 1) The addition of surfactant promotes the slug-to-churn and churn-to-annular transition were shifted to somewhat lower gasflow rates. Simultaneously the foam was better able to suppress the intermittent flow, leading to a narrower range of slug flow and churn flow. 2) The pressure gradients of surfactant solutions were lower than those of pure water especially in slugflow and churnflow regimes, with less irregular flow at low gas velocity. However, the pressure difference of annular flow increased rapidly along the increase of concentration. 3) The liquid holdup was much smaller with surfactant, while tended towards stability by the change of concentration at higher gas flow rate. 4) After surfactant addition, the critical gas velocity decreased sharply by over 40% at inclination angle about 50 ° especially.

10.11885/j.issn.1674-5086.2022.03.10.01