缝洞型碳酸盐岩油藏CO_2注入方式及部位优化  

Optimization of injection manners and injection positions of CO_2 huff and puff in fractured-vuggy carbonate reservoirs

作　　者：赵凤兰[1,2,3] 席园园 侯吉瑞[1,2,3] 王建斐 苏伟[1,2,3] 赵腾[1,2,3] 

机构地区：[1]中国石油大学(北京)提高采收率研究院,北京102249 [2]中国石油大学(北京)石油工程教育部重点实验室,北京102249 [3]中国石化海相油气藏开发重点实验室,北京100086

出　　处：《油气地质与采收率》2017年第2期67-72,共6页Petroleum Geology and Recovery Efficiency

基　　金：国家"973"计划"碳酸盐岩缝洞型油藏开采机理及提高采收率基础研究-缝洞型油藏提高采收率方法研究及优化"(2011CB20100603);国家科技重大专项"碳酸盐岩油田开发关键技术-缝洞型碳酸盐岩油藏提高开发效果技术"(2011ZX05014-003)

摘　　要：缝洞型碳酸盐岩油藏以大型溶洞、溶蚀孔洞及裂缝为主要储集渗流空间,连通方式复杂,非均质性强。CO_2吞吐及CO_2驱替可通过补充地层能量及溶解降粘作用来改善油田开发效果,是一种有效的开发方式。根据现场地质资料,设计并制作室内三维仿真物理模型以模拟典型缝洞油藏单元,通过室内实验模拟CO_2吞吐及CO_2驱替过程,分析生产动态,考察高、低部位井CO_2吞吐的增产效果,并对比高、低部位井CO_2吞吐与驱替对采出程度的影响,在此基础上分析缝洞型碳酸盐岩油藏注气替油机理。实验结果表明:利用底水与次生气顶间的相互作用及井位优势,高部位井CO_2吞吐比低部位井CO_2吞吐采收率高16.09%;利用吞吐与驱替过程中不同的气体控制范围,高、低部位井CO_2吞吐采收率比CO_2驱替采收率分别高8.07%和5.01%,CO_2吞吐效果优于CO_2驱替效果。Large caves,water-eroded pores and cracks are the main reservoir spaces of fractured-vuggy carbonate reservoir with complicated connectivity pattern and strong heterogeneity. CO_2 huff and puff and CO_2 displacement are effective productive method,which can improve development effect by supplying formation energy and reducing oil viscosity through dissolved CO_2 in oil. According to the field geological data,a 3D simulation physical model was designed and used in laboratory experiment to simulate the typical fractured-vuggy reservoir units,and a series of laboratory experiments were carried out to simulate CO_2 huff and puff and CO_2 displacement processes. The dynamics of production was analyzed. The stimulation effect of CO_2 huff and puff in high and low position was researched and the recovery percentage in high or low position with CO_2 huff and puff and CO_2 displacement was compared. On this basis,the mechanism of gas injection and oil displacement in the fractured-vuggy reservoir was analyzed. Experimental results show that the EOR of CO_2 huff and puff in high position is 16.09% higher than that in low position due to the interaction between bottom water and secondary gas cap and the advantage of well location. Taking advantage of the different controlling areas of gas,the oil recovery of CO_2 huff and puff in high and low position is 8.07% and 5.01% higher than that of CO_2 displacement,respectively. The effect of CO_2 huff and puff is superior to that of CO_2 displacement.

关 键 词：缝洞型碳酸盐岩油藏 CO2吞吐 CO2驱替 三维仿真模型 采收率 

分 类 号：TE357.42[石油与天然气工程—油气田开发工程]