【作者】 李洁；

【导师】 侯读杰；

【作者基本信息】 中国地质大学（北京） ， 油气田开发工程， 2009， 博士

【摘要】 储层的孔隙结构是指岩石孔隙和喉道的空间结构,包括孔隙大小和分布、孔隙和喉道的连通情况、孔隙的几何形状和微观非均质特征、孔隙中粘土矿物的成分和产状等,是反映储层微观非均质的重要参数。它不仅控制了石油的运移和储集,而且对储层的产油能力、驱油效率以及最终采收率都有较大的影响。已有研究成果表明,水驱采收率与孔隙结构的某些参数具有较好的相关性,但未见孔隙结构与聚合物驱采收率关系的有关报道。实际上由于聚合物驱与水驱的驱油机理不同,聚合物驱存在不可及孔隙体积,以及岩石对聚合物分子存在吸附和捕集作用,还有聚合物溶液的粘弹性、流变性等等,使得储层的孔隙结构特征对聚合物驱油效果的影响可能会远远大于水驱。因此,有必要开展储层的微观孔隙结构特征对聚合物驱油效果影响这方面的研究。本文应用普通压汞、恒速压汞、铸体薄片分析、电镜扫描等研究手段,通过大量的分析数据,对喇萨杏油田萨葡油层的微观孔隙结构特征进行了研究,建立了储层微观孔隙结构参数与宏观参数(渗透率)的关系;分析了相同油层组在不同地区的孔隙结构差异、同一地区不同油层组之间的孔隙结构差异以及不同相别油层之间的孔隙结构差异,得出:①从平面上来看,葡Ⅰ组油层在萨中孔隙均质性最强,在杏南孔隙非均质性最强;萨尔图油层由北往南孔隙非均质性增强。②从纵向上来看,喇嘛甸葡Ⅰ组油层较萨Ⅱ、萨Ⅲ组油层微观非均质性强;在萨中和杏南则是萨Ⅱ、萨Ⅲ组油层微观非均质性较强。③相同渗透率下,杏南葡I组油层平均孔隙半径略大,微观非均质性较强。结合物理模拟实验结果,应用相关性分析和网络模型,定量研究了孔隙结构参数与聚合物驱效果的关系,并根据影响程度的大小确定了影响聚合物驱效果的主要孔隙结构参数。同时应用多元线性回归、多项式逐步回归以及人工神经网络方法,建立了主控参数与聚合物驱效果的关系方程和预测模型,并对喇萨杏油田萨葡油层聚合物驱提高采收率值进行了预测。本文还提出了一种较实用的计算聚合物驱不可及孔隙体积的方法,可以准确地确定任意分子量聚合物在任意渗透率油层的不可及孔隙体积。发明应用了一种荧光示踪聚合物驱油物理模拟实验方法,可以较直观地观察到聚合物溶液在多孔介质中的流动轨迹。更多还原

【Abstract】 The reservoir pore structure means that space structures of pore and throat space,which include the size and distribution of pore, the connectivity between pore and throat, the geometry and heterogeneity of pore, the component and occurrence of the clay mineral in pore and so on,and they reflect the heterogeneity of reservoir. The pore structure parameters not only control migration and accumulation of oil but have major effect on production capacity and displacement efficiency and final recovery efficiency of the reservoir.The previous research demonstrated that there was preferable correlation between some pore structure and water flooding recovery, but there was not a report about the correlation between pore structure and polymer floodinging recovery. Actually pore structure has bigger effect on polymer floodinging than water floodinging because oil displacement mechanism of polymer floodinging is different from water flooding and polymer flooding has inaccessible pore structure and polymer solution has viscoelasticity and rheological property and adsorption captation effect on rock. So it is necessary to research the effect of microscopic pore structure on polymer floodinging displacement characteristics.This paper used the methods including normal mercury penetration, constant rate mercury penetration, cast thin analysis and electron microscope scanning to analysed the microscopic pore structure of Lasaxing oilfield ,and built the relationship between pore structure parameter and macro-parameter; it also analysed the pore structure divergence in different oil layer and different oilfield:①The pore homogeneity in PI oil layer was the strongest in Sazhong area and the pore heterogeneity was the strongest in Xingnan area; the pore heterogeneity in Saertu oil layer became stronger from north to south;②In Lamadian oilfield, the micro-heterogeneity in PI oil layer was stronger than SII and SIII oil layer; and in Sazhong and Xingnan oil field micro-heterogeneity in SII and SIII oil layer was stronger than PI oil layer.③The average pore radius was bigger and the micro-heterogeneity was stronger in PI oil layer of Xingnan area.Incorporating physical modeling experiment result, it also analysed the quantitative effect of pore structure parameters on polymer flooding displacement characteristics and selected the principal factors; Using the methods of polynomial regression and artificial neural network, it built the relationship equation and forecasting model between principal factors and polymer flooding displacement characteristics and forecasted the polymer flooding recovery in Lasaxing oil filed.This thesis provided an utility method which could calculate the inaccessible pore volume which could establish the inaccessible pore volume of arbitray molecular polymer solution in arbitray permeability reservoir, and invented a polymer floodinging physical modeling method using tracer polymer solution which could watch the flow route of polymer solution in porous media.更多还原