摘要
模拟大庆某注聚油藏 ,制作了包含渗透率和厚度不同的 4个小层的三维非均质物理模型 ,尺寸 80× 80× 4.6 (cm) ,中央设注入井 ,四角设采出井 ,驱替中测定每层测量网点上的压力和电阻率 ,由电阻率求出该点含水率和含油率。驱替程序如下 :水驱至含水 93% ,注入 10 0 0mg/L聚合物溶液 0 .5 7PV(模型 1,聚合物驱 )或先注入 0 .0 3PV调剖剂 ,成胶后注入 0 .5 4PV聚合物溶液 (模型 2 ,调剖 +聚合物驱 ) ,最后均水驱至含水 98% ,实验温度45℃。与聚合物驱相比 ,调剖 +聚合物驱中注聚采收率提高 2 .16 % ,最终采收率提高 2 .18% ,含水率下降滞后(最低点由 1.0 7PV移至 1.33PV) ,注聚后采收率上升也滞后。模型第 3层注入井到 3号采出井方向上 (含高渗条带 ) ,调剖 +聚合物驱中前一段压力梯度增幅较大 ,后一段则较小 ,这是强凝度调剖剂封堵了高渗条带的结果。给出了驱替结束时两个模型各层油饱和度分布图。聚合物驱后的油饱和度 ,第 1和第 4层分别为 0 .42和 0 .48,第 3层 1,2 ,4号采出井方向上为 0 .5 4,3号采出井方向上为 0 .42。与聚合物驱相比 ,调剖 +聚合物驱后第 3层各方向上油饱和度分布趋于均匀 ,第 3层采出油量略减少 。
Simulating a certain polymer flooding reservoir in Daqing, 3-dimensional heterogeneous physical models (80×80×4.6 cm) composed of 4 layers of varying permeability and thickness are made with an injection bore in the center, 4 production bores in corners, and monitoring nets in every layer for measuring pressure and electric resistance (from the later water and oil saturations are obtained). Experimental procedures are as follows: injecting water until water cut of produced fluid reaching 93%; injecting 0.57 PV of 1 g/L polymer solution (model 1, polymer flood (PF) experiment) or squeezing 0.03 PV of a permeability control (PC) fluid and, after its gelation, injecting 0.54 PV of 1 g/L polymer solution( model 2, PC+PF experiment); injecting water until water cut=98%. The experimental temperature 45℃. Comparing with PF experiment on model 1, in PC+PF experiment on model 2 the enhancement in oil recovery by polymer is by 2.18% higher and in ultimate oil recovery - by 2.18% higher, the decrease in water cut is delayed with minimum displaced from 1.07 PV to 1.33 PV of fluids injected and the increase in oil production is delayed, too. In the 3rd layer of model along the direction from injection bore to production bore No3 with a high permeable zone(HPZ) laid, the pressure gradient along the 1st section 15 cm long is higher and along the 2nd section (15 cm long) is lower for PC+PF than that for PF, a result of plugging the HPZ by strong gelled PC fluid. The distribution of residual oil saturation, S o, at the end of the two experiments is given for every layer. The S o values are of 0.42 for the 1st layer, 0.48 for the 4th layer, 0.54 for the 3rd layer in directions to production bore No1,2,and 4 and 0.42 in direction to bore No3 for PF experiment. For PC+PF experiment, the S o distribution becomes more even in the 3rd layer, the oil production from the 3rd layer is slightly lowered and from other 3 layers - increased as compared with PF experiment.
出处
《油田化学》
CAS
CSCD
北大核心
2002年第2期162-166,共5页
Oilfield Chemistry
基金
"九五"国家重点科技攻关项目"大庆油田年产 5 0 0 0吨至 2 0 0 0年稳产技术研究"四级子课题"大型非均质仿真物理模型水驱油实验研究"
关键词
聚合物驱油
调剖
三维非均质模型
驱油效果
剩余油分布
流动压力梯度
封堵高渗条带
大庆油田
polymer flood
successive permeability control and polymer flood
3-dimensional heterogeneous physical model
oil-displacing efficiency
residual oil distribution
flow pressure gradient
plugging high permeable zone
Daqing oil fields
