改进物质平衡法在致密气藏气井生产动态预测中的应用  

Application of improved material balance method in gas well production performance prediction in tight gas reservoirs

作　　者：毕晓明[1] BI Xiaoming(Exploration and Development Research Institute of PetroChina Daqing Oilfield Co Ltd,Daqing 163712,China)

机构地区：[1]中国石油大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712

出　　处：《大庆石油地质与开发》2022年第6期94-101,共8页Petroleum Geology & Oilfield Development in Daqing

基　　金：中国石油股份有限公司重大科技专项“深层天然气高效开发技术研究与应用”(2016E-0211)。

摘　　要：物质平衡法是中高渗气藏气井进行生产动态预测的常用方法,该方法不适用于低渗致密气藏。以气井拟稳定状态流动时的二项式产能方程为基础,采用动态数据校正的方式,对物质平衡法进行了改进。具体方法为:直接采用气井实测的产气量与压力点求取二项式产能方程系数,通过回归方程系数与地层压力间的关系,把物质平衡法中固定的二项式产能方程转换成动态的二项式产能方程,从而能够体现低渗、致密气藏气井的生产动态特征;将原来由3个方程组成的物质平衡法,改进成由二项式产能方程、定容封闭气藏物质平衡方程、井筒管流方程、二项式产能方程系数A经验方程、产能方程系数B经验方程共5个方程组成。应用区块的实际数据检验表明此方法是可行的,改进物质平衡法充分体现了开采对象的动态特点,提高了低渗、致密气藏中气井的动态指标预测精度。Material balance method is a commonly used method for predicting gas well production performance in medium-high permeability gas reservoirs,but not suitable for low-permeability tight gas reservoirs.Based on gas well binomial productivity equation of pseudo-steady state flow,through dynamic data reconciliation,material bal‑ance method is improved.The specific method is that the coefficients of binomial productivity equation are directly calculated by means of measured points of gas production and pressure for gas well.With the help of relationship be‑tween equation coefficients and formation pressure,the fixed binomial productivity equation of material balance method is converted into dynamic binomial productivity equation,to express gas well production performance of lowpermeability tight gas reservoirs.Original material balance method composed of 3 equations is improved as com‑posed of 5 equations,including binomial productivity equation,material balance equation for constant-volume closed gas reservoir,wellbore conduit flow equation,and binomial productivity equation coefficients A and B empiri‑cal equations.The verification of the actual data test in the applied block shows that the improved material balance method is feasible and fully expresses exploited target’s dynamic characteristics,and furthermore the dynamic index predicted precisions have been enhanced for the gas well in low⁃permeability and tight reservoirs.

关 键 词：气井 动态预测 产能方程 物质平衡 稳产期 递减期 

分 类 号：TE345[石油与天然气工程—油气田开发工程]