海洋低渗N油藏驱油效率实验及渗流机理研究

发布时间：2018-11-18 09:19

【摘要】：随着海洋油气资源开发力度的加大,越来越多的优质储量已经被动用,因此加大对海洋低渗透油田的开发并提高其开发效果显得越来越重要。目前,我国陆上低渗透油田的开发已经具有较为成熟的开发理论和技术,可以为海洋低渗透油田的开发提供一定的借鉴意义。但与陆上低渗透油田相比,海上低渗油气田的开发不仅要面对油藏埋藏深、储层物性差、非均质性强、存在启动压力梯度和应力敏感、产量递减快等诸多油藏问题,还要面对由于海洋环境、平台空间和承重受限等诸多不利条件所带来的作业施工挑战。另外,由于海洋油田开发成本较高,对单井产量和采油速度的要求都较高。因此,在研究海洋低渗透油田合理的开发方式时,不仅需要借鉴陆上低渗透油藏开发的经验,又要结合海上油田开发的特点。本文以海洋低渗N油藏为背景,归纳分析了油藏基本地质特征,并根据实验方法与原理,利用天然岩心做了启动压力梯度、驱油效率、润湿性和应力敏感实验。在分析基本地质特征和实验结果的基础上,结合油藏工程及数学模拟软件,分析油藏渗流机理及水驱波及效率的影响因素。论文取得了以下研究成果： (1)进行了工区储层岩心的渗流实验研究,得到了单相水和束缚水饱和条件下单相油的启动压力梯度与流度的关系曲线；进行了水驱油实验,得到8块岩心的相渗曲线,并得到了恒速、变速两种驱替方式的驱油效率与润湿性、注入倍数等的变化关系曲线。 (2)进行了润湿性及应力敏感实验研究,得到了8块岩心的润湿性及有效应力与渗透率的变化关系曲式。 (3)利用油藏工程和渗流力学的方法和原理,对两种典型非均质模式下的非线性渗流规律进行了研究,研究了不同井型的采油能力,并进行了压裂水平井的参数优化。 (4)利用油藏工程及仿真软件研究了直井注水-压裂水平井采油开发井网条件下的渗流场特征,并分析了直井注水-压裂水平井采油开发井网条件下油藏的面积波及效率及垂向波及效率的影响因素。
[Abstract]:With the development of offshore oil and gas resources, more and more high-quality reserves have been used, so it is more and more important to increase the development of marine low-permeability oil fields and improve their development effect. At present, the development of onshore low permeability oil fields in China has more mature development theory and technology, which can be used for reference for the development of marine low permeability oil fields. However, compared with onshore low permeability oil and gas fields, offshore low permeability oil and gas fields not only face many reservoir problems, such as deep reservoir burial, poor reservoir physical property, strong heterogeneity, but also have many reservoir problems, such as starting pressure gradient and stress sensitivity, fast production decline and so on. It also faces the construction challenges caused by many unfavorable conditions, such as ocean environment, platform space and load limitation. In addition, because of the high development cost of offshore oil field, the requirement of single well production and oil recovery speed is higher. Therefore, when studying the reasonable development mode of marine low permeability oil field, we should not only learn from the experience of onshore low permeability reservoir development, but also combine the characteristics of offshore oil field development. In this paper, the basic geological characteristics of marine low permeability N reservoir are summarized and analyzed. According to the experimental method and principle, starting pressure gradient, oil displacement efficiency, wettability and stress sensitivity experiments are carried out by using natural core. Based on the analysis of basic geological characteristics and experimental results, combined with reservoir engineering and mathematical simulation software, this paper analyzes the reservoir percolation mechanism and the influencing factors of water flooding sweep efficiency. The research results are as follows: (1) the experimental study of reservoir core percolation is carried out, and the curve of the relationship between the starting pressure gradient and mobility of single-phase oil under the condition of single-phase water and irreducible water saturation is obtained. The phase and permeability curves of 8 cores were obtained by water flooding experiments, and the relation curves of displacement efficiency, wettability and injection multiple of constant velocity and variable speed displacement were obtained. (2) the wettability and stress sensitivity of 8 cores are studied and the relationship between effective stress and permeability is obtained. (3) by using the methods and principles of reservoir engineering and percolation mechanics, the nonlinear percolation law under two typical heterogeneous modes is studied, the oil recovery ability of different well types is studied, and the parameter optimization of fracturing horizontal well is carried out. (4) using reservoir engineering and simulation software, the characteristics of percolation field under the condition of water injection and fracturing horizontal well development well pattern are studied. The influencing factors of area sweep efficiency and vertical sweep efficiency of reservoir under the condition of water injection and fracturing horizontal well production pattern are analyzed.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE53

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