页岩微纳孔隙流体分布及CO_(2)吞吐动用特征  

Distribution of Fluid in Micro-Nano Pores of Shale and Moving Characteristics of It in CO_(2) Huff-Puff Production

作　　者：张瑞 贾焱 黄熙 陈琦 刘乘宙 茹琦 ZHANG Rui;JIA Yan;HUANG Xi;CHEN Qi;LIU Chengzhou;RU Qi(Laojunmiao Oil Production Plant,PetroChina Yumen Oilfield Company,Jiuquan,Gansu 735200,China;Production Service and Guarantee Center,PetroChina Yumen Oilfield Company,Jiuquan,Gansu 735019,China)

机构地区：[1]中国石油玉门油田分公司老君庙采油厂,甘肃酒泉735200 [2]中国石油玉门油田分公司生产服务保障中心,甘肃酒泉735019

出　　处：《西安石油大学学报（自然科学版）》2024年第5期10-18,共9页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：国家重点研发计划“CO_(2)驱油技术及地质封存安全监测”(2018YFB0605500)。

摘　　要：基于低场岩心核磁共振技术,开展了页岩岩心离心、热处理和CO_(2)吞吐实验,在准确识别可动流体、毛管束缚流体和黏土结合流体T 2截止值的基础上,研究了CO_(2)吞吐对不同孔径孔隙中不同类型流体的动用规律。实验结果表明,目标储层页岩中可动流体平均饱和度为24.0%,毛管束缚流体平均饱和度为33.8%,黏土结合流体平均饱和度为42.18%。CO_(2)吞吐采出油主要来自前2轮吞吐,以大、中孔隙(弛豫时间大于10 ms)中的可动流体为主,而后续吞吐产出油量大幅降低,以中、小孔隙中的毛管束缚流体为主,累积毛管束缚流体动用比例仅为23.1%~37.8%。吞吐后剩余流体以毛管束缚流体和黏土结合流体为主,CO_(2)无法动用黏土结合流体。提高中等孔隙(弛豫时间为10~100 ms)中毛管束缚流体的采出程度是未来页岩增产稳产的关键。In order to clarify the pore type and fluid type effectively utilized in CO_(2) huff-puff of shale,based on low field nuclear magnetic resonance(NMR),the centrifugation,heat treatment and CO_(2) huff-huff experiments of shale cores were carried out to accurately identify T 2 cutoff values of movable fluid,capillary bound fluid and clay bound fluid,and to study the utilization laws of different types of fluids in pores of different sizes.The experimental results show that the average saturation of movable fluid,capillary bound fluid and clay bound fluid is 24.0%,33.8%and 42.18%respectively.The oil produced by CO_(2) huff-puff is mainly from the first two cycles of huff and puff,and mainly from the mobile fluid in large and medium pores(relaxation time is greater than 10 ms).The oil produced by subsequent cycles of huff-puff is mainly from the capillary bound fluid in small and medium pores,and the utilized capillary bound fluid only accounts for 23.1%~37.8%of the total capillary bound fluid.The remaining fluid after huff and puff is mainly capillary bound fluid and clay bound fluid,and the clay bound fluid can not be utilized by CO_(2) huff-puff.Improving the recovery degree of the capillary bound fluid in medium pores(relaxation time is 10~100 ms)is the key to increase and stabilize shale oil production in the future.

关 键 词：CO_(2)吞吐 束缚流体 可动流体 孔隙结构 核磁共振 页岩 

分 类 号：TE357[石油与天然气工程—油气田开发工程]