摘要
为研究CO_2驱沥青质沉积对不同渗透率储集层的微观伤害机理,选取低渗、中渗和高渗岩心进行CO_2驱室内实验,并应用核磁共振技术定量分析驱替后岩心孔喉空间的堵塞程度。实验结果表明,在混相驱阶段,沥青质沉积率明显高于非混相驱阶段,且在不同渗透率岩心中的沉积率基本相同;渗透率伤害率与沥青质沉积率呈正相关,且岩心渗透率越大,渗透率伤害率越小;在混相驱阶段,低渗岩心孔喉堵塞严重,较小孔喉(0.01~1 ms)的堵塞率达到38.19%,高渗岩心的较小孔喉(0.1~5 ms)堵塞率仅有9.59%,显著小于低渗岩心。
In order to study microscopic damage mechanism of asphaltene deposition on reservoirs with different permeabilities during CO2flooding,cores with high,medium and low permeabilities are selected for indoor CO2flooding experiments and plugging degree of porethroat in cores are analyzed quantitatively by using NMR technology.The experimental results show that the deposition rate of asphalteneduring miscible phase stage is obviously higher than that during immiscible phase stage,and the deposition rates are basically same in thecores with different permeabilities;permeability damage rate is positively correlated with the asphaltene deposition rate and the larger thecore permeability,the smaller the permeability damage rate;the pore throats in low-permeability cores are blocked seriously with the plugging rate of relatively small pore throats(0.01~1ms)reaching38.19%,the plugging rate of relatively small pore throats in high-permeability cores is only9.59%,which is significantly lower than the previous one.
作者
王琛
李天太
高辉
赵金省
高媛
窦亮彬
WANG Chen;LI Tiantai;GAO Hui;ZHAO Jinsheng;GAO Yuan;DOU Liangbin(School of Petroleum Engineering, China University of Petroleum, Beijing 102249, China;School of Petroleum Engineering, Xi’an Shiyou University, Xi’an, Shaanxi 710065, China;Shaanxi Gas Group Co. Ltd, Xi’an, Shaanxi 710016, China)
出处
《新疆石油地质》
CAS
CSCD
北大核心
2017年第5期602-606,共5页
Xinjiang Petroleum Geology
基金
国家自然科学基金(51774236
51604224)
中国石油科技创新基金(2017D-5007-0104)
关键词
CO2驱
沥青质沉积
微观伤害机理
孔喉堵塞率
渗透率伤害率
核磁共振技术
CO2 flooding
asphaltene deposition
microscopic damage mechanism
pore throat plugging rate
permeability damage rate
NMR technology
