1School of Petroleum Engineering, University of New South Wales, Sydney, Australia.
2Department of Applied Mathematics, Australian National University, Canberra, Australia
This paper presents experimental data for co-current spontaneous imbibition into cores having bulk volumes from 0.1 to 12 cm3. Simple experiments of brine imbibing into air-filled cores were carried out. Homogeneous sandstone cores (Berea and Bentheimer) and a carbonate core (Mt. Gambier) were used in the experiments. The experimental data were scaled using the scaling laws reported in the literature.
The results demonstrate that reliable experimental data of spontaneous imbibition can be obtained for the small cores of homogeneous porous rocks. Such data are of immense interest for validating the predictive value of network models based on micro-CT images of rock fragments with bulk volumes as small as 0.3 cm3. The data for cores of different sizes were satisfactorily scaled using six different methods (Mattax and Kyte, 1962; Kazemi et al, 1992; Ma et al, 1997; Viksund et al.(1998); Zhou et al, 2002; Li and Horne, 2004). The recovery models proposed by Ma et al (1997) and Viksund et al. (1998) produced an excellent match for the normalized gas recovery data. Although the Li and Horne (2004) model successfully correlated the imbibed water volume as a function of time, the model failed to correlate the normalized recovery data. A comparison of the scaled data with data previously reported for water-gas systems showed excellent agreement.
