一种低渗气藏单井产量递减计算方法及分析——以大牛地盒三气藏为例

低孔、低渗气藏关井压力恢复需要时间较长,不适宜采用试井的方法获取地层参数,因此,采用一种传统与现代相结合的方法来研究大牛地气田盒三气藏的产量递减规律。该产量递减分析方法以Arps产量递减方法为基础,引入Blasingame归一化产量、物质平衡时间和拟时间概念,将变产量/变压降生产数据转变为等效恒定压力系统,运用Fetkovich产量递减标准图版进行拟合,所得匹配点数值分别进行地层参数计算和用于Arps产量预测。该方法提高了产量递减分析的可靠性,具有操作简单的优点,同时可有效求取地层参数。

Well production decline analysis of low permeability gas reservoir:example from H_3 gas reservoir of Daniudi oil field

As pressure recovery will take a long shut-in time for wells in low porosity and low permeability gas reservoir,well test method which is used to obtain formation parameters is not appropriate.A combination of traditional and modern method is used in this paper to study production decline rule of wells in H3 Gas Reservoir of Daniudi Oil Field.This production decline analysis method is based on Arps production decline method,introducing the concept of Blasingame normalized production,material balance time and the adjusted time,turning variable pressure/production data into equivalent constant pressure system.Using Fetkovich's production decline standard chart to carry on the fitting,the matching point data is calculated to get formation parameters and used for Arps method to forecast the production.This method turning variable pressure/production data into equivalent constant pressure system improves the reliability of the production decline analysis,having the advantages of simple operation of Fetkovich production decline method,It also effectively utilized the gas well production data of unstable flow period(transient flow period)to calculate the reservoir parameters.