摘要
超深层气藏一般具有低渗的特征,因而存在启动压力梯度;与此同时,储层岩石渗透率亦随气藏压力或有效覆压的变化而改变。以达西公式为基础,并综合考虑启动压力梯度和压敏效应对超深层气藏渗流规律的影响,建立了新的产能方程。应用于实际气藏计算,结果表明:仅考虑压敏效应或启动压力梯度时气井产能有所下降;当综合考虑这2种因素时,气井产量比单考虑其中一种因素下降幅度更大,其无阻流量约为不考虑压敏效应和启动压力梯度时的71.44%。此结果进一步说明,研究超深层气藏渗流规律及流入动态时,启动压力梯度和压敏效应的影响不可忽略。该研究对深入了解超高压气藏的产能及预测其开发动态和采收率具有一定意义。
Ultra-deep gas reservoirs generally have low-permeability characteristics,so there will be threshold pressure gradient.Meanwhile,the permeability of reservoir rock changes as the gas reservoir pressure or effective overburden pressure changes.Therefore,based on Darcy′s formula and considering the influence of threshold pressure gradient and pressure-sensitive effect on the seepage law of ultra-deep gas reservoir,this paper established a new productivity equation.The established equation was used in a gas reservoir.The calculation result shows that the production of gas well decreased when considering the threshold pressure gradient and pressure-sensitive effect of gas reservoir.When considering one of two effects,the production of the gas well decreased even more and the ratio of the AOF（absolute open flow） is about 71.44% of that when neglecting these two effects.This study also shows that the threshold pressure gradient and pressure-sensitive effect can not be ignored when examining the seepage law and inflowing performance of ultra-deep gas reservoir.This study is significant to deeply understand the productivity,predict the production performance and the recovery factor of ultra-deep gas reservoir.
出处
《断块油气田》
CAS
北大核心
2011年第3期360-362,共3页
Fault-Block Oil & Gas Field
基金
国家自然科学基金项目"超深层油气藏岩石物性垂向分布规律及渗流特征研究"(50874114)资助
关键词
超深层
启动压力梯度
压敏效应
产能方程
ultra-deep formation
threshold pressure gradient
pressure-sensitive effect
productivity equation
作者简介
孙晓旭，女，1986年生，在读油气田开发工程专业硕士研究生，主要从事油气田开发工作。E—mail：sunxiaoxu19860914@163．com。
