页岩气井生产剖面分析及预测模型

An analysis and prediction model of production profile in shale gas well

滕柏路 郭为 曾晶莹 彭越 张晓伟 罗万静 万玉金

中国地质大学（北京）能源学院，北京 100083 中国石油勘探开发研究院，北京 100083

随着压裂技术在页岩气藏领域的大规模应用，气体在页岩基质和裂缝中的流动机理研究变得尤为重要。为了更准确地分析和预测页岩气井的生产剖面，基于流线模拟中的一维飞行时间方法，文中建立了一种计算简便、稳定的体积压裂复杂裂缝网络渗流数学模型：将裂缝性储层离散为以裂缝和储层边界为界限的基质块，将这些基质块的局部性质放大来表示非均质储层，将等压线的轮廓近似为泄流面积的动态边界，引入拟压力推导出可模拟单相气流的流动方程。其中，每个基质块的边界代表储层中的裂缝，通过组合基质块的所有边界来表征非常规气藏中复杂裂缝网络的结构。将该裂缝网络模型在软件上验证，并在一口实际页岩气水平井进行应用。结果表明，建立的数学模型能准确地模拟气井的生产动态。

With the large-scale application of fracturing technology in the shale gas field, it is particularly important to study the flow mechanism of gas between the matrix and fractures. Based on the one-dimensional time of flight  (1D-TOF) method in the streamline simulation, a simple and stable mathematical model for complex fracture network of volume fracturing is established to analyze and predict the production profile of shale gas wells in this paper. By discretizing a fractured reservoir into matrix blocks that are bounded by the fractures and the reservoir boundary, the local properties of these blocks are enlarged to represent the heterogeneous reservoir. The contour of the isobaric line is approximated as the dynamic boundary of the discharge area, and the pseudo pressure is introduced to deduce the flow equation that can simulate single-phase gas flow. Among them, the borders of each matrix block represent the fractures in the reservoir; the configurations of complex fracture networks in unconventional gas reservoir are characterized by assembling all the borders of the matrix blocks. This proposed model is validated against a commercial software. The model is applied to actual shale gas wells, and the results show that the model can accurately simulate the production performance of gas wells. 

10.6056/dkyqt202304009