低渗透多孔介质对高含凝析油型凝析气相态影响  

INFLUENCE OF LOW PERMEABILITY POROUS MEDIUM ON PHASE STATE OF CONDENSATE GAS SYSTEM WITH HIGH CONDENSATE OIL CONTENT

作　　者：汪周华[1,2] 郭平[2] 钟兵[1] 罗涛[1] 张培东[3] 杨涛[4] 

机构地区：[1]西南油气田分公司勘探开发研究院 [2]西南石油大学油气藏地质及开发工程国家重点实验室 [3]胜利油田井下作业公司 [4]中石油西南油气田分公司采气工程研究院

出　　处：《钻采工艺》2009年第3期56-59,共4页Drilling & Production Technology

摘　　要：低渗透气藏在我国已发现的气藏中所占比例较大;由于低渗透多孔介质的影响,与常规高渗气藏相比,开发难度较大,尤其是对于凝析气藏。因此,考虑低渗透多孔介质对凝析气体系的影响对于提高我国低渗透凝析气藏开发水平有一定实际意义。此次研究主要分析低渗透多孔介质对凝析气体系相态特征影响。采用中原桥白气藏实际低渗透储层岩心和配置的高含凝析油型(凝析油含量364g/m3)凝析气样分别从实验、数值模拟角度研究衰竭过程中,多孔介质、初始水饱和度对凝析油饱和度和残余油饱和度的影响,以及多孔介质对凝析气露点压力影响。研究表明:多孔介质中测试的凝析气露点压力高于PVT仪中测试值;对同一块岩心,采用相同的凝析气样品,随着初始含水饱和度的增加,测得的衰竭至大气压下凝析油残余饱和度越小;衰竭过程中,多孔介质中凝析油流动及再蒸发较PVT仪中明显,凝析油残余饱和度低于PVT仪测试值。对于低含凝析油型凝析气,由于致密储层对凝析油的吸附作用明显,岩心测试的残余油饱和度值高于PVT仪测试值,因此,对于这类凝析气藏必须考虑凝析油污染问题。The influence of low permeability porous medium on phase state of condensate gas system was studied.The experiment used the real low permeability core and condensate gas sample with high gas condensate content(containing gas condensate:364g/m3)both of which come from Qiaobai gas field in Zhongyuan to research the effects of the porous media and original water saturation on gas condensate saturation and residual oil saturation and that the porous media on dew pressure of condensate gas.The research results showed that dew pressure of condensate gas measured in porous media is higher testing value of PVT.To the same core with the same condensate gas sample,the residual oil saturation declines with the increasing original water saturation when the pressure is depleted to atmospheric pressure.Gas condensate flow and re-evaporation in porous media are more obvious than in PVT and residual oil saturation of gas condensate is lower than measured in PVT in the process of depletion.To condensate gas with low condensate oil content,residual oil saturation measured in core is higher than in PVT.Therefore,the pollution caused by gas condensate must be considered.

关 键 词：低渗透 多孔介质 凝析气 露点 油饱和度 初始水饱和度 

分 类 号：P618.13[天文地球—矿床学]