仿水平井开发渗流机理及指标预测研究

发布时间：2018-11-06 17:13

【摘要】：特低渗透油藏渗透率低、孔喉小,导致渗流能力低、产能低,在埋藏深、丰度低条件下,常规开发效益差。仿水平井技术是将大型压裂工艺技术与注采开发井网相结合,通过“造长缝、大井距”开发,提高储量动用率和采油速度,对特低渗透油藏的合理开发具有重要意义。本文首先利用油藏数值模拟方法,对仿水平井交错及正对井网的渗流机理、交错井网注水开发及衰竭开发的渗流机理进行了对比分析,研究了仿水平井交错井网注水开发的渗流阶段及贡献度,对比分析了仿水平井、水平井、直井开发的渗流机理,并研究了非均质性对仿水平井开发渗流机理的影响;然后在渗流机理研究的基础上,通过数据统计与油藏数值模拟相结合的方法,对仿水平井实际区块进行开发指标规律分析;最后利用多元线性回归、改进的多元线性回归方法,分别进行了仿水平井开发指标预测模型的建立与校验完善,并对这两种预测模型进行了对比。研究结果表明:仿水平井交错井网相对于正对井网来说,波及系数更大、采出程度更高;仿水平井开发存在近裂缝早期线性流、近裂缝拟径向流、系统线性流三个主要的渗流阶段,其中系统线性流阶段的产能贡献度达到95%以上;仿水平井交错井网开发时,剩余油主要分布于油井连线附近,是后期加密调整的重点;利用改进的多元线性回归方法得到的指标预测模型准确度较高。研究成果可为致密砂岩特低渗油藏仿水平井开发提供理论指导和技术支持。
[Abstract]:Low permeability and low pore throat lead to low percolation capacity and low productivity. Under the condition of deep buried depth and low abundance the conventional development benefit is poor. Horizontal well imitating technology is a combination of large fracturing technology and injection-production development well pattern. It is of great significance to reasonable development of ultra-low permeability reservoir by "making long fractures and long well spacing" to improve the production rate of reserves and oil recovery rate. In this paper, by using reservoir numerical simulation method, the percolation mechanism of horizontal well pattern and vertical well pattern, the seepage mechanism of cross well pattern water injection development and failure development are compared and analyzed. The percolation stage and contribution of horizontal well pattern in horizontal well pattern are studied. The seepage mechanism of horizontal well and vertical well development is compared and analyzed, and the influence of heterogeneity on the seepage mechanism of horizontal well development is studied. Then on the basis of the study of percolation mechanism, through the combination of data statistics and reservoir numerical simulation, the development index law of the actual horizontal well block is analyzed. Finally, by using multivariate linear regression and improved multivariate linear regression method, the prediction model of horizontal well development index is established and verified, and the two prediction models are compared. The results show that the cross well pattern of horizontal well is larger in sweep coefficient and higher in recovery degree than that in positive pattern. There are three main percolation stages in the development of imitating horizontal wells: early linear flow near fracture, quasi-radial flow near fracture and linear flow in the system, in which the productivity contribution of system linear flow is more than 95%. In the development of horizontal well pattern, the remaining oil is mainly distributed near the oil well line, which is the emphasis of later infilling adjustment, and the accuracy of the index prediction model obtained by the improved multivariate linear regression method is high. The research results can provide theoretical guidance and technical support for the development of horizontal wells in tight sandstone ultra-low permeability reservoirs.
【学位授予单位】：中国石油大学(华东)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE312

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