页岩油井缝网改造后CO_(2)吞吐与埋存特征及其主控因素  

Characteristics and its main controlling factors of CO_(2) huff-and-puff and storage of shale oil wells after fracture-network stimulation

作　　者：赵续荣 陈志明 李得轩 李格轩 廖新维[1] 强海伟 ZHAO Xurong;CHEN Zhiming;LI Dexuan;LI Gexuan;LIAO Xinwei;QIANG Haiwei(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(Beijing),Beijing 102249,China;Downhole Operation Engineering Company of Yanchang Oilfield Co Ltd,Yan’an 716000,China)

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [2]延长油田股份有限公司井下作业工程公司,陕西延安716000

出　　处：《大庆石油地质与开发》2023年第6期140-150,共11页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家自然科学基金项目“基于试井理论和数据驱动的页岩油藏三维裂缝网络参数智能反演”(52074322);国家自然科学基金项目“基于智能数值试井的页岩油压后井间干扰参数评价”(52274046)。

摘　　要：为了明确裂缝性页岩储层注CO_(2)吞吐后的埋存效果,探究注CO_(2)吞吐实现CO_(2)有效埋存的可行性,通过建立含复杂缝网的页岩油井CO_(2)吞吐与埋存数值模型,对比不同生产与裂缝参数下的吞吐与埋存特征,并引入灰色关联分析方法确定了影响CO_(2)吞吐与埋存效果的主控因素。结果表明:CO_(2)吞吐不仅可以提高页岩油的采收率,而且可以实现部分CO_(2)的有效埋存,埋存系数可达0.40;注CO_(2)吞吐开发页岩油藏时,吞吐和埋存效果随着吞吐轮次、注入速度、闷井时间和周期注入量等生产参数的增大而增强,其中吞吐轮次对吞吐效果影响最大,可使累计产油量增加22.12%,注入速度对埋存效果影响最大,可使埋存系数达到0.40;CO_(2)吞吐时间越晚,累计产油量越少,但埋存系数越大,累计产油量每年减少3.47%,埋存系数每年增加39.48%;页岩储层裂缝条数、长度的增加有利于提高采收率、实现更多的CO_(2)埋藏,累计产油量最大可增加85.18%,埋存系数最大可增加20.90%。研究成果对页岩油注CO_(2)提高采收率现场实践具有参考意义。In order to understand storage effect of CO_(2) huff-and-puff in fractured shale reservoirs and explore feasibility of effective CO_(2) storage by CO_(2) huff-and-puff,a numerical model of CO_(2) huff-and-puff and storage of shale oil wells with complex fracture networks is established for comparison of characteristics of huff-and-puff and storage with different production parameters and fracture parameters.Grey correlation analysis method is introduced to determine main controlling factors of CO_(2) huff-and-puff and storage.The results show that CO_(2) huff-and-puff can not only improve shale oil recovery,but also achieve effective storage of partial CO_(2) with storage coefficient of 0.40.When CO_(2) huff-and-puff is used in shale oil reservoirs development,the effect of huff-and-puff and storage is improved with increment of production parameters including huff-and-puff rounds,injection rate,soaking time and cyclic injection volume,among which huff-and-puff round has the most influence on huff-and-puff effect with cumulative oil production increased by 22.12%,and injection rate has the most influence on storage effect with storage coefficient reaching 0.40.The later the CO_(2) huff-and-puff is,the less the cumulative oil production is,and the higher the storage coefficient is,with cumulative oil production decreased annually by 3.47%and storage coefficient increased annually by 39.48%.Increase of number and length of fractures in shale reservoir is beneficial to improve oil recovery and achieve more CO_(2) storage,with cumulative oil production increased maximally by 85.18%and storage coefficient increased maximally by 20.90%.The research has reference significance for field practice of enhanced oil recovery by CO_(2) injection in shale oil reservoirs.

关 键 词：页岩油 CO_(2)吞吐 CO_(2)埋存 复杂缝网 灰色关联度 

分 类 号：TE341[石油与天然气工程—油气田开发工程]