低渗油藏注气前缘运移特征及影响因素  

Migration characteristics and influencing factors of gas injection front in lowpermeability reservoirs

作　　者：顾骁 王智林 葛永涛[1] 阎焕玉 GU Xiao;WANG Zhilin;GE Yongtao;YAN Huanyu(Exploration and Development Research Institute of Jiangsu Oilfield Company,SINOPEC,Yangzhou 225009,China)

机构地区：[1]中国石化江苏油田分公司勘探开发研究院,江苏扬州225009

出　　处：《复杂油气藏》2024年第3期342-346,共5页Complex Hydrocarbon Reservoirs

摘　　要：CO_(2)气驱过程中,对气相前缘运移及影响因素的研究有助于我们预防气窜,改善开发效果。基于长岩心CO_(2)驱替实验及X-CT测试,揭示了非均质性对气相前缘运移的影响。通过抽提机理模型数值模拟总结了非均质条件下的压力前缘、组分前缘、气相前缘的运移特征,明确了不同的注入速度对气驱前缘运移的影响规律。研究表明:气驱前缘的运移速度会随着渗透率的上升而增大,高渗岩心中的气相前缘运移速度比低渗快25%以上;机理模型中,七点法情况下压力前缘接近六边形,而气相前缘和组分前缘接近于菱形;随着注入时间的增加,气相前缘的移动速度先减小后增加,后期移动速度上升,速度越来越大,且注气速度越大,气相前缘移动速度越快。研究结果为低渗油藏气驱开发的前缘预测及控制提供依据。In the process of CO_(2) gas flooding,the study of the gas front migration and influencing factors can help us to prevent gas channeling,improving the development effect.Based on long-core CO_(2) displacement experiments and X-CT tests,this paper reveals the influence of heterogeneity on the migration of the gas injection front.The numerical simulation of the extraction mechanism model summarizes the migration characteristics of the pressure front,component front,and gas injection front under heterogeneous conditions,clarifying the influence of different injection rates on the migration of the gas-driving leading edge.The results show that the migration speed of the gas injection front increases with the increase of permeability,and the migration speed in high-permeability cores is more than 25%faster than that in low-permeability.In the mechanism model,the pressure leading edge is close to hexagonal in the case of the seven-point method,while the gas displacement front and the component front are close to the rhombus.With the increase of injection time,the moving speed of the gas front decreases and then increases,and the rising speed of the gas front migration in the later stage becomes bigger and bigger.Furthermore,the higher the gas injection speed is,the faster the speed of the gas front migration becomes.The research results provide a basis for the prediction and control of the gas injection front in the development of lowpermeability reservoirs.

关 键 词：前缘运移 CT饱和度测试 非均质性 数值模拟 注气速度 

分 类 号：TE348[石油与天然气工程—油气田开发工程]