牙哈凝析气藏注气开发过程反蒸发动态相态特征  

Retrograde vaporization dynamic phase behaviors in gas injection development of the Yaha condensate gas reservoir

作　　者：陈文龙[1] 廖发明[1] 吕波[2] 苗继军[2] 常志强[2] 

机构地区：[1]西南石油大学研究生学院 [2]中国石油塔里木油田公司

出　　处：《天然气工业》2012年第8期67-70,131-132,共4页Natural Gas Industry

基　　金："十二五"CNPC重大科技攻关专项"天然气开发关键技术研究"(编号:2011B-1507)资助

摘　　要：针对牙哈凝析气藏出现的反凝析问题,利用油气相平衡理论,在对典型气井YH301井地层流体相态实验拟合的基础上,模拟研究了该凝析气藏的反凝析相态特征和组分变化特征,同时分析了注入气与地层剩余凝析油和剩余井流物的反蒸发相态变化特征。结果表明:①随着地层压力的降低,凝析气中C1含量逐渐增加,C10+的含量逐渐降低,反之也成立;②加载不同比例注入气后,随着注入气比例从20%增加到80%,地层反凝析油的p—T相图临界点从右向左偏移,当注入气摩尔含量超过40%后,整个体系在地层温度134℃下已经变成露点状态;③地下剩余流体注气后混合物体系反凝析液量降低,注入气所占摩尔含量越高,反凝析液量降低越多;④注入气摩尔含量大于40%有利于降低体系露点压力和反凝析液量,使凝析气不会再显著发生反凝析损失,反凝析饱和度明显降低,有利于牙哈凝析气藏开发中后期进一步提高凝析油的采收率。Concerning the problem of the retrograde condensation in the Yaha condensate gas reservoir,we adopted the oil-gas phase equilibrium theory to conduct a simulation research into the retrograde condensate phase behavior and its composition variation in the condensate gas reservoir based on the formation fluid phase behavior experiment on the typical gas well YH301.At the same time we analyzed the behavior variation of retrograde vaporization phase of the injected gas,the formation residual condensate oil and the residual well fluids.The following conclusions are drawn.First,as the formation pressure decreases,the content of C1 contained in the condensate oil increases and that of C10+ gradually decreases,and vice versa.Second,if different percentages of the injected gas is added,the critical point of formation condensate oil in the p-T phase diagram moves from the right to the left as the percentage increases from 20 to 80,and when the molar content of injected gas is above 40 percent,the system is turned into the dew point state at 134℃ of the formation temperature.Third,when gas is injected into the subsurface residual fluid,the retrograde condensate liquid of the mixture system decreases;and the higher the molar content of the injected gas,the less the retrograde condensate liquid.Fourth,when the molar content of the injected gas is above 40 percent,the dew point pressure of the system and retrograde condensation loss are reduced;with the obvious decrease of retrograde condensate oil saturation,the recovery efficiency of condensate oil will be further improved in the later development of the Yaha condensate gas reservoir.

关 键 词：凝析油气田 注气 开发 反蒸发 动态 相态 采收率 塔里木盆地 牙哈凝析气藏 

分 类 号：P618.13[天文地球—矿床学]