基于多重烃类运移机制的页岩气藏多级压裂水平井渗流机理与模型研究

项目名称： 基于多重烃类运移机制的页岩气藏多级压裂水平井渗流机理与模型研究

项目编号： No.51304165

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 矿业工程

项目作者： 王海涛

作者单位： 西南石油大学

项目金额： 25万元

中文摘要： 页岩气藏孔隙结构的多尺度性及特殊的烃类赋存方式，决定了页岩储层中复杂的烃类运移机制，包括吸附-解吸、扩散、粘性流、应力敏感等。此外，压裂水平井已被证实是开采页岩气藏的最有效方法，水平井压裂后在地层中形成复杂的裂缝网络系统，包括压裂缝、诱导缝、天然缝的连通以及应力释放形成的径向缝，使得本就复杂的页岩气藏渗流规律变得更加复杂。常规渗流理论不足以刻画页岩气藏中压裂水平井的渗流特征，而这将不可避免地导致矿场实践的盲动性甚至开发策略的失败。本课题将在综合考虑页岩气多重运移机制和地层中复杂裂缝网络的基础上，建立页岩气藏多级压裂水平井不稳定渗流模型（包括不稳定试井和产能预测模型），采用数学物理方法对其进行求解及编程实现，并对压力及产量动态的主要影响参数进行敏感性分析，从而形成一套较完整的页岩气藏不稳定试井分析及不稳态产能预测方法，可用于气藏及气井动态参数的反求和压裂参数的优化，科学指导页岩气藏高效开发。

中文关键词： 页岩气藏；吸附/解吸；扩散；多级压裂水平井；渗流

英文摘要： Shale gas reservoirs have complex, multimodal pore-size distributions and unique storage properties, causing shale gas to be transported by multiple flow mechanisms through the pore structure which include desorption from the surface of kerogen, diffusion in kerogen, viscous flow and stress sensitive. Multiply-fractured horizontal wells (MFHW) have been proved to be the most effective way to produce from shale gas reservoirs. Due to the complex fracture network created or induced by hydraulic fracturing, including primary fractures, second fractures, radial fractures in the immediate neighborhood of the horizontal well as a result of stress release and reconnection of natural fractures, which makes it more difficult to model gas flow in shale gas reservoirs with MFHW. Current gas flowing theories become inadequate to describe the multiple flow mechanisms in this kind of reservoir-well configuration, which will inevitably lead to blindness in practice and failure in developing strategy. Based on the consideration of multiple migration mechanisms in shale gas reservoirs and analysis of the complicated fracture network, this work will try to establish flowing models for MFHW in shale gas reservoirs, including transient well testing model and rate prediction model. The models will then be solved analytically or nume

英文关键词： Shale gas reservoir；Adsorption/Desorption；Diffusion；Multi-stage fractured horizontal well；Seepage flow