A statistical analysis of the effects of pressure, temperature and salinity on contact angles in CO<inf>2</inf>-brine-quartz systems

Abstract

An integrative data analysis was performed using previously published contact-angle data for CO<inf>2</inf>-brine-quartz systems. Linear mixed-effects models were used to perform exploratory analyses of the influence of pressure, temperature and salinity on contact angles for subcritical and supercritical CO<inf>2</inf> conditions. The results confirm that there is a large disparity in the magnitude and behaviour of contact angles between studies; accommodating this disparity through the use of a random effect suggests that changes in pressure are important mostly in the subcritical CO<inf>2</inf> pressure range. Brine concentration and temperature are both statistically and practically relevant to the wettability of quartz in CO<inf>2</inf>-brine systems across both pressure regimes.