Layered injection technology for chemical flooding of Class-Ⅲ oil reservoirs in the Daqing Oil Fields complex,Songliao Basin,Northeast China  

作　　者：Haicheng Li 

机构地区：[1]Research Institute of Oil Production Engineering,Daqing Oil Fields complex Co.,Ltd.,Daqing,Heilingjiang,163453,China [2]Heilongjiang Provincial Key Laboratory of Oil and Gas Reservoir Stimulation,Daqing,Heilingjiang,163453,China

出　　处：《Energy Geoscience》2023年第1期51-58,共8页能源地球科学（英文）

基　　金：sponsored by the key consulting project of the Chinese Academy of Engineering entitled Research on the Sustainable Development Strategy of China's High Water-cut Old Oilfields(No.2019-XZ-15);the National major project entitled Large Oil and Gas Field and Coalbed Methane Development(No.:2016ZX05010006).

摘　　要：The Class-Ⅲ oil reservoirs of Lasaxing oilfield in the Daqing Oil Fields complex have geological oil reserves of 1.86 billion tonnes,an oil recovery of 39%,with remaining reserves accounting for more than 45%of the total geological reserves of the oilfield.Therefore,they have considerable potential for future oil production.The current layered injection technologies fail to achieve effective control over the low single-layer injection rates since they can only produce low throttle differential pressure under low injection rates(5-20 m^(3)/d).In this study,a symmetrically-structured double-offset-hole injection allocator and a novel throttling component were developed.Their spatial layout was constructed and mechanical parameters were optimized using finite element analysis,which allows for expanding the flow rate range at low injection rates.According to experimental results,the throttle differential pressure increased from 0.2 MPa to 0.8 MPa at an injection rate of 5 m^(3)/d,and the range of the single-layer flow rates expanded from 20-70 m^(3)/d to 5-70 m3/d.The field test results show that the effective production of oil layers with medium and low permeability was achieved and that the ratio of producing oil layer thickness to the total reservoir thickness increased by 9.7%on average.Therefore,this study provides valuable technical support for the effective chemical-flooding-based development of Class-Ⅲ oil reservoirs.

关 键 词：Chemical flooding Layered injection technology Low injection rate Lasaxing oilfield Daqing Oil Fields complex Songliao Basin 

分 类 号：P618.13[天文地球—矿床学]