摘要
长深气藏天然气富含CO2,尚未常规方法计算其高压物性参数及其相态特征分析.针对这一特殊性,采用室内PVT实验进行测定与分析.研究表明,对于含CO2天然气,其压缩因子、密度、体积系数、等温压缩系数在低压(20 MPa以下)时表现出很强的压力敏感性,而水蒸气含量则表现相反,绝对黏度则始终保持较强的压力敏感性;压缩因子、密度、绝对黏度、水蒸气含量随着CO2含量增大而变化幅度较大,对CO2的敏感性较强,而体积系数对CO2的敏感性较弱,等温压缩系数对CO2则无敏感性.长深气藏的原始地层温度(140℃)和井口温度(40℃)均在气液两相区之外,可以判断在开发过程(从气层到井口分离器)中流体不穿过两相区,表明该气藏为干气气藏.
The natural gas in Changshen gas reservoir is of high content of CO2.There are no conventional methods for calculating the physical parameters of the natural gas and analyzing its phase behaviors at high-pressure.In view of this specificity,the physical parameters and the phase behaviors are determined and analyzed by PVT laboratory experiments.Experimental studies show that,at low pressure (below 20 MPa),the compressibility factor,density,volume factor and isothermal compressibility factor have strong sensitivity to pressure,but the steam content is not sensitive to pressure.And the absolute viscosity is always to maintain strong pressure sensitivity.The compressibility factor,density,absolute viscosity and steam content increase stronger than volume factor and isothermal compressibility factor with the increase of CO2 content.Both gas reservoir temperature (140 ℃) and wellhead temperature (40 ℃) are outside gas-liquid two-phase zone.So it can be judged that the gas reservoir is a dry gas reservoir,and the fluid does not pass through the two-phase region in the development process of the natural gas (from gas reservoir to wellhead separator).
出处
《西安石油大学学报（自然科学版）》
CAS
北大核心
2011年第1期45-47,118-119,共3页
Journal of Xi’an Shiyou University（Natural Science Edition）
基金
国家重点基础研究发展规划项目"温室气体提高石油采收率的资源化利用及地下埋存"(编号:2006CB705800)
关键词
长深气藏
高压物性
相态特征
Changshen gas reservoir
high-pressure physical property
phase behavior
