火山岩气藏水平井产能评价研究

发布时间：2018-03-11 22:26

本文选题：火山岩气藏　切入点：裂缝-孔隙型　出处：《西南石油大学》2015年硕士论文　论文类型：学位论文

【摘要】：火山岩天然气藏作为一个新的勘探开发领域,其天然气资源丰富、勘探开发前景广阔。目前我国己探明火山岩天然气地质储量达数千亿立方米,储量规模属世界最大。在当前国家能源需求迅速增长的背景下,火山岩天然气资源的开发,对于保障国家能源安全、优化能源结构、改善环境具有重大意义。与常规砂岩气藏相比,火山岩气藏储层具有较为复杂的储渗模式,发育孔、洞、缝多重介质,从而决定了火山岩储层的储层物性差、渗流机理复杂,且缺乏适合于火山岩气藏复杂渗流特性的产能评价模型。本文综合运用现代渗流力学、油气藏工程、数学物理方法、计算机程序设计等学科知识,研究在不同介质条件下,水平井及压裂水平井不稳态渗流理论、产能评价模型,为火山岩气藏开发提供理论依据。本文完成的主要工作如下： (1)对国内外文献进行了大量调研,总结了火山岩气藏渗流机理,地质特征,储层特征及开采难点,同时总结了常规水平井和压裂水平井的产能评价方法。 (2)从火山岩气藏的基本渗流理论出发,考虑了井筒储集和表皮效应的影响,建立裂缝—孔隙型火山岩气藏水平井不稳态渗流数学模型,运用拉普拉斯变换、傅里叶变换对模型进行了求解,得出了各种外边界条件下渗流模型的拉普拉斯空间解,绘制了产能特征曲线,对产能特征曲线进行了流动阶段的划分,分析了各参数对曲线动态的影响。 (3)建立了裂缝—孔隙型火山岩气藏有限导流压裂水平井不稳态渗流模型,在模型中引入了裂缝离散化机制,采用半解析法求解渗流数学模型,并绘制了产能特征曲线,对产能特征曲线进行了流动阶段的划分,分析了各参数对曲线形态的影响。 (4)建立了裂缝—孔隙型火山岩气藏无限导流压裂水平井不稳态渗流模型,考虑了人工裂缝内的流动阻力,采用半解析法求解渗流数学模型,并进行了产能特征曲线对比和分析。 (5)运用建立的火山岩气藏产能模型对实例井进行了拟合分析,应用结果表明本文所建立的模型理论正确、方法可行。
[Abstract]:As a new field of exploration and development, volcanic gas reservoirs are rich in natural gas resources and have broad prospects for exploration and development. At present, hundreds of billions of cubic meters of volcanic natural gas reserves have been proved in China. The scale of reserves is the largest in the world. Under the background of the rapid growth of national energy demand, the exploitation of volcanic natural gas resources is of great significance to ensure the national energy security, optimize the energy structure and improve the environment. Compared with conventional sandstone gas reservoirs, volcanic gas reservoirs have a more complex reservoir and permeability model, developing pores, cavities and fractures with multiple media, which determines that the reservoir physical properties of volcanic reservoirs are poor, and the percolation mechanism is complex. There is a lack of productivity evaluation model suitable for the complex percolation characteristics of volcanic gas reservoirs. In this paper, the knowledge of modern seepage mechanics, reservoir engineering, mathematical and physical methods, computer programming and so on is used to study the different media conditions. The unsteady percolation theory and productivity evaluation model of horizontal wells and fracturing horizontal wells provide theoretical basis for the development of volcanic gas reservoirs. The main work of this paper is as follows:. 1) A large number of literatures at home and abroad have been investigated, and the percolation mechanism, geological characteristics, reservoir characteristics and production difficulties of volcanic gas reservoirs have been summarized. At the same time, the productivity evaluation methods of conventional horizontal wells and fracturing horizontal wells have been summarized. Based on the basic percolation theory of volcanic gas reservoir, considering the influence of wellbore reservoir and skin effect, the mathematical model of unsteady seepage in horizontal well of fractured and porous volcanic gas reservoir is established, and Laplace transformation is used. Fourier transform is used to solve the model. The Laplace space solution of seepage model under various external boundary conditions is obtained. The productivity characteristic curve is drawn, and the productivity characteristic curve is divided into flow stages. The influence of the parameters on the curve dynamics is analyzed. In this paper, the unsteady seepage model of fractured porous volcanic gas reservoir with finite conductivity fracturing is established. The fracture discretization mechanism is introduced into the model, and the mathematical model of seepage flow is solved by semi-analytical method, and the characteristic curve of productivity is drawn. The characteristic curve of productivity is divided into flow stages and the influence of each parameter on the shape of the curve is analyzed. In this paper, an unsteady seepage model of fractured porous volcanic gas reservoir with infinite diversion fracturing is established. Considering the flow resistance in artificial fracture, the mathematical model of seepage is solved by semi-analytical method, and the characteristic curve of productivity is compared and analyzed. 5) the model of volcanic gas reservoir is used to fit and analyze the example well. The application results show that the theory of the model is correct and the method is feasible.
【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】：TE328

【参考文献】