页岩气井产量递减分析方法选择研究

Selection of production decline analysis method of shale gas well

页岩气藏开发递减规律有Arps模型、SEPD模型、Duong模型以及它们之间的组合模型等。Arps递减规律是气井产量递减分析的主要方法。递减规律模型的选择主要有两种方法:第一种是单一的转化为线性关系,利用线性回归,选择相关系数高的作为分析方法。第二种组合递减模型,可以组合成多种模型,主要利用非线性回归,选择相关系数高的作为分析方法。提出一种新的选择产量递减分析方法,利用各种递减规律的线性组合,分析每种递减规律与实际生产数据的关联程度,根据关联程度的高低排序选择递减分析方法,该方法通过实际生产数据分析,生产数据拟合精度高,为递减分析方法选择提供依据。

There are several methods of the production decline analysis during the shale gas reservoir development,such as the Arps model,the SEPD model,the Duong model and their composition models.Among them,the Arps model is the main method.There are two main choices of the appropriate decline methods.One is to transform the data into the linear relationship and the meth-od with high correlation coefficient can be deemed as the better model.The other is to use the non-linear regression by the combina-tion of the above models and choose the analysis method with high correlation coefficient.Then we proposed a new method to choose the production decline analysis model,and obtained the relation degree by comparing the linear combination of the different decline analysis models with the practical production data,furthermore,according to the degree of correlation in order,selected the produc-tion decline analysis method.This method is validated by the high fitting precision between the calculated results and the produc-tion data,which provides a reliable and reasonable way to choose the production decline models.