疏松砂岩密闭取芯井新鲜样品和洗油样品相对渗透率曲线差异性研究  

Study on Difference Between Relative Permeability Curves of Fresh and Washed Unconsolidated Sandstone Cores from Sealed Coring Wells

作　　者：李金宜 陈丹磬 周凤军 朱文森 信召玲 张旭东 

机构地区：[1]中海石油天津分公司渤海石油研究院,天津300459 [2]中海油实验中心渤海实验中心,天津300452

出　　处：《西安石油大学学报（自然科学版）》2018年第1期39-46,共8页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：国家科技重大专项课题"渤海油田加密调整及提高采收率油藏工程技术示范"(2016ZX05058-001-005)

摘　　要：基于渤海某典型高孔高渗疏松砂岩稀油油藏密闭取岩心,对同一样品先后分别完成新鲜样品相渗实验和洗油样品相渗实验。实验结果表明:中水淹层段样品在洗油后油水相渗曲线与新鲜状态下相渗曲线各关键参数均非常接近;未水淹层段样品在洗油后状态下完成的油水相渗曲线与新鲜状态下相渗曲线相比,束缚水饱和度较高,残余油饱和度较低,两相区范围接近,最终驱油效率较高。未水淹层段岩心若采用洗油后的柱塞进行油水相渗实验,其结果将偏离真实储层渗流规律。根据水淹程度对油水相渗曲线影响的认识,重构了考虑水淹影响的"全寿命"油水相对渗透率曲线。矿场数值模拟结果表明,采用考虑水淹影响的重构相渗曲线的模型,在相同采出程度下,其含水率更低;在相同含水率情况下,其采出程度更高。The relative permeability experiments of the fresh and washed sealed coring samples from a typical high porosity and high permeability unconsolidated sandstone reservoir in Bohai oilfield were carried out. The experimental results show that: for the core samples of medium waterflooded layer,the key parameters of the oil-water relative permeability curves of fresh cores are close to those of washed cores; for the core samples of non-waterflooded layer,compared with the oil-water relative permeability curves of fresh cores,the irreducible water saturation of washed cores is higher,the residual oil saturation is lower,the two-phase region is close,and the final oil displacement efficiency is higher. Therefore,the oil-water relative permeability experiment results of non-waterflooded layer cores deviate from the true seepage law of reservoir. Considering the effect of waterflooded degree on the oil-water relative permeability curve,a " full life" oil-water relative permeability curve is constructed. Numerical simulation result shows that using the " full life" oil-water relative permeability curve in which the influence of waterflooded level is considered,the recovery percent of reserves is higher under the same water-cut,and the water-cut is lower at the same recovery percent of reserves.

关 键 词：疏松砂岩 密闭取芯井 水淹程度 油水相对渗透率 

分 类 号：TE122.23[石油与天然气工程—油气勘探]