Study on CO2 Miscible and Near-miscible Region Flooding in Low Permeability Reservoirs
Whether CO2 flooding can be mixed with crude oil under reservoir conditions directly affects the oil displacement efficiency,therefore CO2 miscible and near miscible flooding in low permeability reser-voirs is studied.By conducting flooding experiment in both homogeneous and heterogeneous rectangular cores,oil recovery results were acquired through the various series of experiments considering permeabili-ty,migration distance,permeability ratio as well as the flooding pressure under the simulated reservoir conditions.Therefore,the classification of the immiscible,near-miscible and miscible CO2 flooding in low permeability reservoir was determined by the gas flooding results,and the near miscible area was also de-fined.The minimum miscible pressure(MMP)of CO2 with crude oil is 18.5 MPa in this study,which is 0.7 MPa higher than that determined by slim tube experiment(17.8 MPa),a conventional method to de-termine the carbon dioxide MMP.Based on the displacement curve,the CO2 flooding process is divided into three stages,immiscible,near miscible and miscible region.The near-miscible pressure of CO2 dis-placement in YC oil ranges from 16.5 MPa to 18.5 MPa.The minimum miscible pressure(MMP)meas-uring of CO2 flooding is determined by core flooding method and the near miscible flooding area is defined.This experimental method offers reference to the further understanding of mechanism in CO2 near-misci-ble displacement and scheme design of CO2 flooding in YC oilfield.
Low permeability reservoir carbon dioxide near-miscible flooding miscible pressure core dis-placement experiment
Meng Zhang Fenglan Zhao Liguang Song Zhixing Wang
Enhanced Oil Recovery Institution,China University of Petroleum(Beijing),Beijing,102200,China
国内会议
青岛
英文
148-154
2018-06-20（万方平台首次上网日期，不代表论文的发表时间）