裂缝性油藏油水相渗曲线实验研究

发布时间：2019-01-29 05:25

【摘要】：目前,随着世界原油消费量的增大,占探明储量近一半的裂缝性油藏逐渐受到重视。与孔隙性油藏相比裂缝性油藏非均质性强,油水流动规律复杂,其相对渗透率受储层因素(岩石物性、裂缝网络模式等)、流体因素(润湿性、油水黏度比等)、驱替因素(驱替压差、驱替流速等)多方面影响,故其相渗资料的获取相对困难。因此,深入研究裂缝性油藏的相渗曲线影响因素并得出计算方法具有十分重要的意义。本文以裂缝性碳酸盐岩油藏的相渗曲线计算模型为主要研究对象,在充分调研相渗曲线的获取途径及裂缝性油藏室内物理模拟方法的基础上,根据裂缝网络的地质成因、油田地质资料考虑相似原理设计制作了可视化大模型和全直径岩心模型,开展了多次水驱油实验,提出了裂缝性油藏的相渗曲线获取方法。取得的主要研究成果如下： 1)设计制作了不同缝网模式的实验模型并制定了相应的实验方案参考油田地质资料,依照相似原理,着重考虑缝网模式、缝宽度相似性,制做了两种缝网模式的可视化大模型(斜交缝和复杂缝)以及两种缝网模式的全直径岩心模型(平行缝和斜交缝)；制定了以上两类模型的实验方案,通过实验研究油水黏度比、驱替速度和缝网模式对相渗的影响。 2)开展了一系列可视化大模型水驱油实验通过该部分实验,分析了不同缝网模式、不同油水黏度比下的相渗曲线形态和含水率变化,并结合实验现象阐述水驱油流动特征和剩余油分布规律。研究认为裂缝中的油水相渗及剩余油分布受以上两方面因素的综合影响。 3)开展了一系列全直径岩心水驱油实验作为可视化大模型实验的补充,该部分实验在高温高压环境下完成。该部分实验另外考虑了驱替速度对水驱油的影响,认为驱替速度适中有利于最大限度减少剩余油并且最佳的驱替速度受油水黏度比和缝网模式的综合影响。 4)通过实验数据拟合和理论推导得到两种用于裂缝性油藏的相渗计算模型通过拟合可视化大模型实验测得的相渗数据,得到了考虑缝网复杂程度、油水黏度比的相渗计算经验公式；通过理论推导的方法得到考虑缝宽分布的相渗计算模型,分析认为若缝宽服从正态分布N(μ,(?)2),则μ越大等渗点越靠右,(?)2越大等渗点越靠左。
[Abstract]:At present, with the increase of world crude oil consumption, fractured reservoirs, which account for nearly half of proven reserves, have been paid more and more attention. Compared with porous reservoir, fractured reservoir has stronger heterogeneity, more complex oil-water flow law, and its relative permeability is affected by reservoir factors (rock physical property, fracture network model, etc.), fluid factor (wettability, oil-water viscosity ratio, etc.), Because of the influence of displacement factors (displacement pressure difference, displacement velocity, etc.), it is difficult to obtain the permeability data. Therefore, it is of great significance to study the factors affecting the permeability curve of fractured reservoir and obtain the calculation method. In this paper, the computational model of facies and permeability curve of fractured carbonate reservoir is taken as the main research object. Based on the investigation of the way of obtaining phase and permeability curve and the method of indoor physical simulation of fractured carbonate reservoir, the geological origin of fracture network is considered. The large visual model and the full diameter core model are designed and made by considering the similarity principle of oilfield geological data. Several experiments of water flooding have been carried out and the method of obtaining the phase and permeability curve of fractured reservoir has been put forward. The main research results are as follows: 1) the experimental models of different fracture pattern are designed and made, and the corresponding experimental schemes are drawn up to refer to the geological data of oil fields. According to the principle of similarity, the fracture pattern is considered emphatically. Because of the similarity of seam width, two kinds of visual large models (oblique joints and complex joints) and two kinds of full-diameter core models (parallel joints and oblique joints) were made. The experimental schemes of the above two kinds of models are worked out, and the effects of oil-water viscosity ratio, displacement speed and fracture pattern on the permeability are studied. 2) A series of visualized large model water flooding experiments were carried out. Through this part of experiments, the changes of phase permeability curve and water cut under different fracture pattern and different oil-water viscosity ratio were analyzed. Combined with experimental phenomena, the characteristics of water drive oil flow and the distribution of remaining oil are described. It is considered that the oil-water phase permeability and the remaining oil distribution in the fracture are affected by the above two factors. 3) A series of full-diameter core water flooding experiments were carried out as a supplement to the visualized large-scale model experiment, which was completed in high temperature and high pressure environment. In addition, the effect of displacement velocity on water drive oil is considered in this part of the experiment. It is considered that the moderate displacement rate is conducive to the maximum reduction of remaining oil and the optimum displacement velocity is affected by the oil / water viscosity ratio and the fracture pattern. 4) through experimental data fitting and theoretical derivation, two kinds of phase permeability calculation models used in fractured reservoirs are obtained, and the permeability data measured by visual large model experiments are fitted, and the complexity of fracture network is taken into account. Empirical formula for calculation of oil-water viscosity ratio; Based on the theoretical derivation method, a phase permeability calculation model considering the distribution of fracture width is obtained. It is considered that if the seam width is from the normal distribution N (渭, (?) 2), the larger the equal permeability point 渭 is, the right the equal permeability point is, and the larger the equiosmotic point is, the left the equal permeability point is.
【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】：TE312

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