Full text loading...
-
Estimation Of CO2 Penetrating Pore Throat Diameter Based On CO2 Miscible Flood Experimental Results
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, ECMOR XVI - 16th European Conference on the Mathematics of Oil Recovery, Sep 2018, Volume 2018, p.1 - 9
Abstract
CO2 enhanced oil recovery (EOR) has been commercially applied all over the world to produce more oil. The CO2 function is to attain minimum miscibility pressures at reasonably low pressure compared with reservoir pressure. This generates CO2 miscible flooding leading to more preferable oil recovery. Even under such a preferable condition, 100% oil recovery is rarely seen in laboratory experiments: coreflood and slimtube tests. However, compositional simulation of gas-injection sometimes predicted zero oil saturation in certain grids. To decrease a gap between practical and numerical phenomenon, Hiraiwa et al. (2007) developed a method of incorporating residual oil saturation obtained in laboratory coreflood experiments. The concept of Sorm was defined as the residual oil saturation that did not decrease less than user-prescribed values. To evaluate CO2 EOR more practically, the laboratory results were used to estimate Sorm in core scale for numerical modelling. This paper presents extensive laboratory results of unsteady state oil displacement by 15PV CO2 much more than usual CO2 coreflood experiments of 2–3 PV. By properly considering such on-site reality into account for laboratory core flooding design, a core scale Sorm can be obtained. Based on the Sorm, CO2-penetrating pore throat size was discussed in this study.