CO_2或N_2压裂凝析气藏后近缝带烃类的相态分析  

Hydrocarbon Phase Behavior Analysis around Fracture after CO_2 or N_2 Fracturing Condensate Gas Reservoir

作　　者：位云生[1] 胡永全[2] 张啸枫[1] 张俊良[3] 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]西南石油大学油气藏地质及开发工程国家重点实验室,四川成都610500 [3]西南油气旧分公司川东北气矿工程技术与监督部,四川达州635000

出　　处：《石油钻探技术》2008年第3期84-86,共3页Petroleum Drilling Techniques

基　　金：四川省天然气开采重点实验室项目“凝析气藏压裂优化设计”(编号:GPL0409)部分研究内容

摘　　要：以中原白庙凝析气田白52井为例,研究了CO2或N2压裂停泵时刻裂缝周围的相态变化。首先分析了压后近缝带烃类组分和相态,然后借助牛顿拉夫森算法,对烃类的相态变化及凝析油饱和度进行了计算,得到了凝析气藏近缝带不同温度和压力下烃类的相态分布情况,以及随着地层中注入气体摩尔分数变化,烃类相态的变化情况。同时,对注入CO2或N2后的相态变化结果进行了定量对比分析。结果表明,注入CO2或N2在储层中的摩尔分数不同时,它们对烃类相态的影响程度是不同的;储层中注入相同摩尔分数的CO2或N2的优劣程度也是不一样的。这对优化凝析气藏压裂的气体类型、气体用量、排量及压裂规模,提高我国低渗透凝析气藏压裂井产量和采出程度具有重要的现实意义。Using Well Bai-52 in Baimiao condensate gas reservoir, Zhongyuan Oilfield as an example, phase behavior around fracture was investigated after CO2 or N2 fracturing was stopped. First of all, hydrocarbon composition and phase behavior around fracture was analyzed, then phase behavior of the hydrocarbon and condensate oil saturation was calculated by Newton-Raphson algorithm. The distribution of phase behavior around fracture under different temperature and pressure, and the phase behavior change with the change of injected gas molecule percentage were obtained. The results indicate that when molecule percentage of CO2 or N2 was different, the impact on hydrocarbon was different; the effect of CO2 and N2 was different with the same mole injection. This research is important to optimize gas type, gas volume, displacement and fracturing scale in fracturing condensate gas reservoir, and to increase fractured well productivity and degree of reserve recovery in low permeable condensate reservoirs.

关 键 词：凝析油气田 气体压裂 相态 凝析油饱和度 露点压力 

分 类 号：TE357.28[石油与天然气工程—油气田开发工程]