致密砂岩产水气井气举排液模型研究

苏里格气田是典型的致密砂岩气藏，其有效储层含水饱和度高，气、水层混杂分布，开发中后期一般因井筒积液阻碍天然气有效开发，往往需要排液才能保持一定的产量，目前气举是排液较为有效的方法，然而如何提高排液效率及优化气井排液制度已成为制约气举排液效果的难题。以高产水生产气井为研究对象，根据油套管质量、动量和能量方程，建立了气举井筒排液模型，运用显示欧拉差分方法对其进行求解。基于所建立的气井井筒排液模型，研究了不同注气量、井口油压等参数对气井排液效率的影响程度，并分析了S井气举排液过程中产液量、产气量以及排液时间等工作指标变化特征。研究成果为致密砂岩产水气井提高排液效率，以及气举排液生产制度优化提供了一定的指导。

Study on gas-lift drainage model of tight sandstone water-producing gas well

The Sulige gas field is one of the typical tight sandstone gas reservoirs in China, the reservoir features high water saturation in the effective reservoir and mixed distribution of gas and water layers. During the middle and late stages of development, the effective development of natural gas is usually hindered by fluid accumulation in the wellbore, and fluid drainage is often required to maintain sustain production. In this paper, a gas lift wellbore drainage model is developed based on the oil casing''s mass, momentum, and energy equations, and it is solved using Eulerian difference method. Based on the established gas wellbore drainage model, the degree of influence of different parameters, e.g., gas injection volume and wellhead oil pressure on the drainage efficiency of gas wells has been studied, and variables such as fluid production, gas production and drainage time during gas lift drainage of S wells are analyzed, which provide guidance for improving drainage efficiency of water-producing gas wells in tight sandstone and optimizing gas lift drainage production.