基于质量含油率的湖相页岩油可动资源评价——以渤海湾盆地沧东凹陷孔二段为例  

Assessment of movable resources of lacustrine shale oil based on mass oil content:a case study of the 2nd member of Kongdian formation in Cangdong Sag of the Bohai Bay Basin

作　　者：窦煜 韩文中[1] 王文东[2] 董姜畅 王娜[1] 李昊东 勐睿 DOU Yu;HAN Wenzhong;WANG Wendong;DONG Jiangchang;WANG Na;LI Haodong;MENG Rui(Exploration&Development Research Institute of Dagang Oilfield,Tianjin 300280,P.R.China;School of Petroleum Engineering,China University of Petroleum(East China),Qingdao 266580,Shandong Province,P.R.China)

机构地区：[1]大港油田勘探开发研究院,天津300280 [2]中国石油大学(华东)石油工程学院,青岛266580

出　　处：《深圳大学学报（理工版）》2024年第1期33-41,共9页Journal of Shenzhen University(Science and Engineering)

基　　金：国家重点基础研究发展计划资助项目(2022YFF0801200);国家自然科学基金资助项目(52274056);中国石油天然气股份有限公司科学研究与技术开发资助项目(2021DQ0508)

摘　　要：页岩样品中普遍存在烃类散失和有机质吸附,导致页岩油可动资源评价不准,为解决该难题,利用中国渤海湾盆地沧东凹陷孔二段G19-25井45 m密闭取心,创新设计了45块次3类(0 h与24 h、密闭与开放、常规与多温阶)页岩热解对比实验和12块次干酪根溶胀实验,构建了轻烃恢复校正系数和有机质吸附系数.研究表明,样品放置24 h后轻烃平均损失率为29.4%,开放条件下碎样轻烃平均损失率为21.0%,常规热解轻烃平均损失率为15.5%,综合平均损失率为47.1%,即原始地层状态下页岩滞留烃量是常规热解游离烃量的2倍(页岩油轻烃校正系数为2.0);页岩中单位有机质吸附烃量随着镜质体反射率Ro增加而逐渐降低,当Ro为0.8%~1.1%时,页岩有机质吸附油量平均为0.1(质量分数).本研究创建页岩油可动资源评价的质量含油率新方法,提出用页岩质量含油率表征页岩滞留烃去除有机质吸附烃后的页岩中可动烃量,评价孔二段页岩油可动资源量为6.8×10^(8)t,研究成果可为类似盆地页岩油研究提供借鉴.Shale samples commonly exhibit hydrocarbon losses and organic matter adsorption,leading to inaccurate assessments of movable shale oil resources.To address this challenge,a closed-core sample was obtained at a depth of 45 meters from well G19-25 in the Kong 2th Member of the Cangdong Sag in the Bohai Bay Basin,China.An innovative approach was adopted,involving 45 sets of comparative experiments,categorized into three types(0 h vs.24 h,closed vs.open,conventional vs.multi-temperature stages)for shale pyrolysis,and 12 sets of kerogen swelling experiments.This study established correction coefficients for light hydrocarbon recovery and organic matter adsorption.The results indicate that the average light hydrocarbon loss rate after 24 hours sample placement is 29.4%.Under open condition,the average light hydrocarbon loss rate for fractured samples is 21.0%,while for conventional pyrolysis,the average light hydrocarbon loss rate is 15.5%,and the average comprehensive loss ratio is 47.1%.The underground original light hydrocarbon is approximately twice that of conventional pyrolysis(shale oil light hydrocarbon correction coefficient Kcal=2.0).The 12 sets of kerogen swelling experiments show that the amount of hydrocarbon adsorbed by kerogen gradually decreased with the increase of vitrinite reflectance Ro.Specifically,when Ro is between 0.8%and 1.1%,the average adsorption coefficient for shale organic matter is 0.1.A novel methodology for assessing the quality oil content method in shale oil movable resources is established,which suggests using the shale oil content rate(mass fraction of oil)Sf to characterize the movable hydrocarbon content in shale after removing hydrocarbons adsorbed by organic matter.According to this approach,the quantity of movable shale oil resources in the Kong 2th member of the Kongdian formation is 6.8×10^(8) t.This method can provide reference for similar shale oil research in comparable basins.

关 键 词：地质学 页岩油 资源评价 含油率 多温阶热解 孔二段 沧东凹陷 

分 类 号：TE155[石油与天然气工程—油气勘探]