One of the problems encountered in waterflooding projects is scale formation caused by chemical incompatibility between potential injection waters and reservoir brine. Chemical compatibility evaluation through laboratory experiments on cores at reservoir conditions is of limited value because only first-contact phenomena are reproduced. A numerical model is presented that couples a reservoir-fluid-flow/thermal-equilibrium simulator with a chemical-equilibrium computer code. This model, AGIPS, enables us to calculate the evolution in time of the amount of scale formed at any point in the reservoir and inside the wells when changes occur in the temperature of the injected water and when the injection water mixes with reservoir brine. Moreover, the model calculates temperature and pressure profiles in the reservoir, together with their evolution in time, taking into account the permeability reduction caused by scale formation. Results are presented for the chemical-equilibrium code validation by matching experimental data on scale formation in mixtures of incompatible waters. An example is also given of the use of AGIPS in simulating a five-spot waterflood where incompatible water is injected.
1 H spin-lattice relaxation and other physical properties are compared to study the oil-water-surface interplay in suitably chosen and prepared natural porous media of different wettability. Whereas the water-oil arrangement is well established for both strongly water wet and strongly oil wet porous media, the problem is still open for intermediate wettability surfaces. Relaxation behavior reflects the pore space geometry and shows wettability effects on sweeping efficiency and on immiscible liquid arrangement in well-defined equilibrium situations. A simple picture at the pore-length scale is verified for strongly water wet samples, whereas a more complex picture arises for intermediate wettability samples.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.