Petroleum and Refinery

Biography

Biography: Bjørn Kvamme

Abstract

In this paper, we focus on the geological storage of CO₂ in reservoirs with zones that are cold enough to facilitate CO₂ hydrate formation at local pressures. A 2D hydro-chemical mechanical model which has five layers (three layers with aquifers and two layers with cap rock in which we introduced two fractures) is created. We apply a reactive transport reservoir simulator, RetrasoCodeBright (RCB), in which hydrate is treated as a pseudo mineral. Following the recent modifications to account for hydrate dynamics in the code through a kinetic approach, we have further improved the simulator to implement the non-equilibrium thermodynamic calculations. In the present study, we spot the light on the hydrate formation effects on porosity in different regions, as well as on the flow pattern. These simulations are based on classical relationships between porosity and permeability, but the outline of ongoing modifications is presented as well. A critical question in such systems is whether hydrate formation can contribute to stabilizing the storage, given that hydrates are pore filling and cannot be stable toward mineral surfaces. The implications of hydrate formation on the geo-mechanical properties of the model reservoir are other aspects addressed in this study. This is an ongoing study with a constant development of adding new phase transitions involving hydrate into the simulator. Hydrate formation from aqueous solutions of hydrate formers is the most recent addition. Hydrate formation from primary or secondary adsorption on minerals is in progress. The overall goals is a hydrate simulator that can imitate real production scenarios (pressure reduction, temperature change, CO₂ injection) but also become a tool for estimating leakage fluxed of methane due to contact between hydrate and ground water under saturated with methane.