凝析气体积系数理论方程新形式推导及应用  

Derivation and application of the new theory equation of condensate gas volume coefficient

作　　者：康志勇 张兴文 黄祥光 回岩 李龙 KANG Zhiyong;ZHANG Xingwen;HUANG Xiangguang;HUI Yan;LI Long(Research Institute of Exploration and Development,Liaohe Oilfield Company,PetroChina,Panjin 124010,China)

机构地区：[1]中国石油辽河油田公司勘探开发研究院,辽宁盘錦124010

出　　处：《天然气地球科学》2021年第9期1403-1409,共7页Natural Gas Geoscience

基　　金：中国石油天然气股份公司科技重大专项“辽河油田千万吨稳产关键技术研究与应用”(编号:2017E-16)资助。

摘　　要：为了解决凝析气体积系数在凝析气藏评价中高压物性(PVT)取样分析成本高,借用天然气体积系数公式计算精度又明显偏低这一实际问题,以凝析气体积系数定义及气体状态方程为理论基础推导并建立了凝析气体积系数新方程,同时建立了地层凝析气摩尔组分反演公式。用新方程计算凝析气组分和凝析气体积系数的应用效果明显优于传统方法。采用生产气油比和凝析油密度可将地面天然气组分和凝析油组分还原为地层凝析气组分,且反演精度大于99%;采用新建凝析气体积系数理论方程计算凝析气体积系数不仅大幅降低凝析气PVT取样分析成本,计算精度也由72.9%提升到86.2%,满足了凝析气藏在勘探开发各阶段的评价研究需求。In order to solve the practical problem about high pressure physical property(PVT)sampling and analysis cost of condensate gas volume coefficient in the evaluation of condensate gas reservoirs and the low accuracy of natural gas volume coefficient of condensate formula,a new equation of condensate gas volume coefficient was deduced and established based on the definition of condensate gas volume coefficient and gas state equation.At the same time,the inversion formula of molar composition of the formation condensate gas molar is established.The application effect of the new equation in calculating the condensate gas composition and volume coefficient is obviously better than that of the traditional methods.Using the production gas-oil ratio and condensate density can revert the ground natural gas component and condensate component to the formation condensate gas component,the inversion accuracy is greater than 99%.Using the new theoretical equation of condensate gas volume coefficient to calculate condensate gas volume coefficient not only greatly reduces the cost of PVT sampling analysis of condensate gas,but also improves the calculation accuracy from 72.9%to 86.2%,which meets the evaluation and research needs of condensate gas reservoir in any stage of exploration and development.

关 键 词：凝析气体积系数 凝析气密度 凝析气组分 天然气组分 气体偏差系数(气体压缩因子) 体积换算系数 

分 类 号：TE372[石油与天然气工程—油气田开发工程]