稠油油藏注CO_(2)吞吐提高采收率机制  

EOR mechanisms of CO_(2) huff and puff process for heavy oil recovery

作　　者：王晓燕[1,2] 章杨 张杰[1] 程海鹰[1] 姬虎军[3] 汪文昌 李辉 梁晨[5] 李陈洋[6] 张亮 WANG Xiaoyan;ZHANG Yang;ZHANG Jie;CHENG Haiying;JI Hujun;WANG Wenchang;LI Hui;LIANG Chen;LI Chenyang;ZHANG Liang(Oil Production Technology Research Institute,Dagang Oilfield,PetroChina,Tianjin 300280,China;School of Petroleum Engineering,Northeast Petroleum University,Daqing 163318,China;The 2nd Oil Production Plant,Dagang Oilfield,PetroChina,Tianjin 300280,China;Engineering Technology Department,Dagang Oilfield,PetroChina,Tianjin 300280,China;Research Institute of Exploration and Development,Dagang Oilfield,PetroChina,Tianjin 300280,China;School of Petroleum Engineering in China University of Petroleum(East China),Qingdao 266580,China;Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)),Ministry of Education,Qingdao 266580,China)

机构地区：[1]中国石油大港油田采油工艺研究院,天津300280 [2]东北石油大学石油工程学院,黑龙江大庆163318 [3]中国石油大港油田第二采油厂,天津300280 [4]中国石油大港油田工程技术处,天津300280 [5]中国石油大港油田勘探开发研究院,天津300280 [6]中国石油大学(华东)石油工程学院,山东青岛266580 [7]非常规油气开发教育部重点实验室(中国石油大学(华东)),山东青岛266580

出　　处：《中国石油大学学报（自然科学版）》2021年第6期102-111,共10页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：中国石油天然气股份有限公司重大科技专项(2018E-11-07)。

摘　　要：以大港油田埕隆1601稠油油藏为例,采用高温高压PVT试验装置和填砂管驱替试验装置,开展CO_(2)-原油体系高压物性测定和CO_(2)吞吐增产效果评价;采用油藏数值模拟方法,开展先导CO_(2)吞吐水平井生产历史拟合和增产机制分析。结果表明:油藏条件下,CO_(2)-原油界面张力为2.9 mN/m,为非混相状态;CO_(2)在原油中的溶解度为45 m^(3)/t,膨胀系数为1.17,降黏率达到99.18%;依靠扩散作用CO_(2)在原油中的溶解速度仅为0.0059 mL/mL/min,而在动态混溶条件下CO_(2)溶解速率可达0.2912 mL/mL/min;超临界CO_(2)主要萃取原油中C5~C14烷烃组分,剩余油中芳香烃、胶质及沥青质含量提高10.14%,原油黏度略微增加;先导试验井CO_(2)吞吐增产效果显著,换油率达1.21,高于室内试验平均值,主要发挥CO_(2)溶胀降黏、溶解气驱及抑制底水锥进的增产机制,底水对扩大CO_(2)波及体积和补充地层能量有一定积极作用。A heavy oil sample from Dagang Oilfield was used to study the EOR mechanisms of CO_(2) huff and puff process using a PVT device and a sand-pack displacement set-up.The properties and interactions of the CO_(2)-crude oil system were measured under high pressure and temperature conditions,along with the reservoir numerical simulation carried out for the history matching of the pilot testing of the CO_(2) huff and puff operation in a horizontal well.The results show that,under reservoir conditions,the interfacial tension between CO_(2) and the heavy oil sample is 2.9 mN/m,which is immiscible.The solubility of CO_(2) in the crude oil is 45 m^(3)/t,with the expansion coefficient of 1.17,in which the viscosity reduction rate can reach to 99.18%.The dissolution rate of CO_(2) in the heavy oil by diffusion at static condition is only 0.0059 mL/mL/min,but it can reach to 0.2912 mL/mL/min under condition of dynamic miscibility.Supercritical CO_(2) can effectively extract C5-C14 alkane components from the crude oil,which makes the content of aromatics,resin and asphaltene in the remaining oil increase by 10.14%,and a slight increase of the oil viscosity.In the field pilot testing,an excellent performance of CO_(2) huff and puff process has been achieved in a horizontal well,in which the CO_(2)-oil exchange ratio was of 1.21,larger than that measured in the laboratory.The EOR mechanisms of the CO_(2) huff and puff process mainly include oil swelling and viscosity reduction,dissolved gas drive and inhibition of bottom water coning in the field operation,while the bottom water can have a positive effect on increasing CO_(2) sweep volume and supplementing formation energy.

关 键 词：稠油 CO_(2) 溶胀降黏 溶解扩散 界面张力 提高采收率机制 

分 类 号：TE357[石油与天然气工程—油气田开发工程]