Towards a Deterministic Approach to Calcite Scaling in the Porous Media During CO2 Sequestration and Immiscible CO2 Flooding

Abstract

Scale deposition has been known to occur in porous media when the existing fluid becomes supersaturated based on changes in the ambient pressures and temperatures. Studies have been performed on the generation of mathematical models for evaluating scales in radial flow. Scaling is a well-known problem in producing wells, and prediction models from thermodynamic and kinetic aspects have been provided, and methods have been addressed in the industry to solve this problem. In this study, calcite deposition in the reservoir during CO2 injection processes is evaluated deterministically. Limited studies have been performed on calcite scaling in porous media with a reservoir simulation tool. CO2 EOR and sequestration has been widely analyzed. However, the mineralization factor has only been looked at from a CO2 storage point of view. Some light on the possible effects of calcite precipitation has on oil production. Calcite scaling tends to reduce the cross-sectional flow area for fluids in the pores, thus resulting in a permeability reduction which hampers levels of oil production. In order to quantify scale deposition in porous media, four different simulation cases were studied: 1. CO2 storage in an aquifer model, 2.CO2 EOR in a Light-Oil reservoir model, 3.CO2 storage in an aquifer-like lab-scale core model along with sensitivities. For the field-scale aquifer case, the effect of temperature, salinity, and heterogeneity on calcite deposition in the aquifer. CO2-EOR along with miscible and immiscible CO2 flooding were studied, to visualize the presence of calcite precipitation and its impact on oil recovery.