中深层特稠油重力泄油模拟实验  

Experiments of physical simulation of gravity drainage for a mid-deep extra-heavy oil reservoir

作　　者：王成[1] 钟立国[1] 刘建斌 刘义刚 张伟 WANG Cheng;ZHONG Liguo;LIU Jianbin;LIU Yigang;ZHANG Wei(Institute of Unconventional Oil and Gas Science and Technology,China University of Petroleum-Beijing,Beijing 102249,China;Tianjin Subcompany of CNOOC,Tianjin 300459,China)

机构地区：[1]中国石油大学(北京)非常规油气科学技术研究院,北京102249 [2]中海石油(中国)有限公司天津分公司,天津300459

出　　处：《石油科学通报》2019年第4期378-389,共12页Petroleum Science Bulletin

基　　金：国家科技重大专项“海上稠油热采调剖工艺及配套技术研究”(2016ZX05058-003-007);国家自然科学基金面上项目“蒸汽—气体协同驱替与重力泄油开采方法研究”(51474227)资助

摘　　要：针对原始地层压力较高的中深层特稠油油藏,为了研究重力泄油开采效果,利用高温高压三维物理模拟系统开展了重力泄油模拟实验。研究了不同压力下SAGD生产过程蒸汽腔发育特征和生产动态特征,优选出中深层特稠油开展SAGD的合理压力范围;对比了SAGD和MFAGD的开采效果,研究了气水比对MFAGD开采效果的影响。在此基础上,提出了高效开采高压稠油油藏的重力泄油方法,即SAGD转MFAGD,并对MFAGD开采阶段的气水比进行了优化。研究结果表明:SAGD生产压力对蒸汽腔扩展和开采动态具有明显的影响。生产压力高时,蒸汽腔扩展慢,开采初期蒸汽腔呈椭圆状、产油量上升较慢。蒸汽腔升至油藏顶部后,蒸汽腔上部向两侧扩展速度加快,蒸汽腔呈"漏斗"形。生产压力越高,蒸汽腔温度越高,蒸汽腔内残余油饱和度越低,SAGD开采采收率越高。但是,生产压力越高,采出液温度也越高,对采油设备的要求越高。结合油田现场条件,推荐SAGD生产阶段的生产压力为5~7 MPa。MFAGD开采初期产量上升快,开采后期产量递减较慢,瞬时产油量和瞬时油汽较高。随着气水比的增加,MFAGD阶段采油量和累积油汽比均上升。但气水比超过50后,阶段采油量和累积油汽比上升幅度减缓。在生产压力5 MPa条件下,MFAGD推荐气水比为50。在相同生产压力下,SAGD后期转MFAGD开采可提高采收率5%左右。SAGD转MFAGD开采的初期建议采用较高的气水比,后期逐渐降低。To study the development of gravity drainage, physical simulation experiments were conducted with a high-temperature and high-pressure 3 D physical simulation system for a mid-deep extra-heavy oil reservoir. The characteristics of steam chamber development and production dynamics in SAGD processes under different pressures were studied to optimize the reasonable production pressure for SAGD development in a mid-deep extra-heavy oil reservoir. The development effects of SAGD and MFAGD(Multi-thermal Fluid Assisted Gravity Drainage) were compared, and the influence of gas-water ratio on the development effects of MFAGD was studied. On this basis, a gravity drainage method, SAGD-MFAGD, is proposed to efficiently develop high-pressure heavy oil reservoirs, and the gas-water ratio in the MFAGD stage is optimized. The research results show that the production pressure of SAGD has a significant effect on steam chamber expansion and recovery performance. At higher production pressure, the steam chamber expands slowly, and at the initial stage of production, the steam chamber is elliptical and the oil production rises slowly. After the steam chamber rises to the top of the reservoir, the upper part of the steam chamber expands to both sides at a faster speed, and the steam chamber is shaped like a funnel. The higher the production pressure, the higher the temperature of the steam chamber, the lower the residual oil saturation in the steam chamber, and the higher the recovery rate of SAGD production. However, the temperature of produced fluid increases with the increase of production pressure. If the temperature of the produced fluid is too high, it will damage the production equipment. Based on the oilfield conditions, it is recommended that the production pressure in SAGD process is 5~7 MPa. In the early stage of MFAGD, oil production increases rapidly, while in the later stage of MFAGD, oil production decreases slowly, and instantaneous oil production and the instantaneous oil-steam ratio are higher. With an increase of

关 键 词：蒸汽辅助重力泄油 多元热流体辅助重力泄油 物理模拟实验 中深层特稠油油藏 

分 类 号：TE53[石油与天然气工程—油气田开发工程]