深层页岩气吸附模型和物质平衡新方法

Deep Shale Gas Adsorption Model and New Material Balance Method

准确评价深层页岩气井单井最终可采储量(EUR)对页岩气的高效开发具有重要意义。调研深层页岩气吸附模型,基于各模型对吸附数据的拟合程度优选出考虑深层页岩气吸附因素的T-Langmuir模型。基于T-Langmuir模型表征的深层页岩气吸附特征和流动物质平衡方程基本原理,建立考虑深层页岩气吸附特征的流动物质平衡新方法,并计算了四川盆地某页岩气井的单井最终可采储量。研究结果表明:T-Langmuir模型在高压条件下拟合效果较好,可以作为深层页岩气的吸附模型。新方法计算的单井最终可采储量为1.397×10^(8) m^(3),比传统方法的计算结果大0.109×10^(8) m^(3),经过和其他方法对比,新方法计算结果更为准确。

Accurate evaluation of single well dynamic reserves(EUR)of deep shale gas wells is of great significance for the efficient development of shale gas.The adsorption models of deep shale gas are investigated,and the T-Langmuir model considering the adsorption factors of deep shale gas is optimized based on the fitting degree of each model to the adsorption data.Based on the adsorption characteristics of deep shale gas characterized by T-Langmuir model and the basic principle of flow material balance equation,a new method of flow material balance considering the adsorption characteristics of deep shale gas is established and the single well EUR of a shale gas well in Sichuan Basin is calculated.The results show that the T-Langmuir model has a good fitting effect under high pressure conditions and can be used as an adsorption model for deep shale gas.The EUR of single well calculated by the new method is 1.397×10^(8) m^(3),which is 0.109×10^(8) m^(3) larger than that calculated by the traditional method.Compared with other methods,the new method is more accurate.