基于分段拟合的致密气藏递减分析方法  

Production decline analysis method of fracturing gas well in tight reservoir based on partitioned imitation

作　　者：刘会会[1,2] 崔越华[1,2] 吴优 江乾锋 杨辉[1,2] LIU Huihui;CUI Yuehua;WU You;JIANG Qianfeng;YANG Hui(Research Institute of Exploration and Development,PetroChina Changqing Oilfield Company,Xi′an Shaanxi 710018,China;National Engineering Laboratory for Exploration&Development of Low-Permeability Oil&Gas Field,Xi′an Shaanxi 710018,China)

机构地区：[1]中国石油长庆油田分公司勘探开发研究院,陕西西安710018 [2]低渗透油气田勘探开发国家工程实验室,陕西西安710018

出　　处：《石油化工应用》2020年第3期20-24,共5页Petrochemical Industry Application

摘　　要：Arps递减模型的适用条件之一是气井生产达到边界控制流阶段,应用Arps递减模型对苏里格致密砂岩气藏压裂气井产量进行递减分析时,存在以下难点:如何确定气井到达边界控制流的时间;达到边界控制流阶段的气井,如何进一步判断其递减类型。为此,根据苏里格气田气井生产特征,结合试井理论及数值模拟方法,建立不同类型气井数值模型,确定气井到达边界控制流时间,以此为分界点,分段拟合,研究不同阶段气井产量变化规律。结果表明:已进入边界控制流的气井,递减指数介于(0,1),为0.5左右,属于双曲递减的一种特殊形式-衰竭递减。利用研究成果能够合理有效的预测气井不同生产阶段的生产指标及变化规律,对致密砂岩气藏压裂气井的产量递减分析及指标预测有一定的指导意义。The main assumption of the traditional decline analysis(Arps)is boundary dominated flow(BDF).If the prerequisite is violated and inaccurate forecasts may result. Then,how to forecast the production-index preliminarily for the gas wells during transient flow,and how to choose the decline type for the gas wells during BDF, are the difficulties of production forecasting for tight gas reservoirs, for example, Sulige gasfield. The goal of this work is to research the production development of gas well during different stages,by means of building numerical model to simulate the behaviour of fracturing gas well and study the duration before BDF. Study results show that the decline exponent of gas well during BDF is about 0.5, which is depleting decline and a special form of hyperbolic decline.Using the research,we can forecast the behaviour and production-index of gas well during different stages rationally and effectively, which has important directive to the production forecasting of fracturing gas well in Sulige tight gas reservoir.

关 键 词：致密气藏 苏里格气田 Arps递减模型 边界控制流 分段拟合 递减指数 

分 类 号：TE328[石油与天然气工程—油气田开发工程]