| Abstract |
The Powder River Basin is one of the primary hydrocarbon-bearing basins in the state of Wyoming. This provides consequential knowledge on the basin's characteristics, which allows effective identification of potential candidates for CO2 storage. In this paper, we aim to characterize the hydration of Portland cement in CO2 injection wells. Properties of the Minnelusa formation in the Powder River Basin serve as a base case scenario. From this, we will run a sensitivity analysis to determine the influence of various parameters on cement hydration. These parameters consist of pressure, temperature, formation water fraction, and water-to-cement ratios. The findings will allow us to determine the most influential parameters affecting cement hydration, hence threatening the integrity of CCUS operations. For this purpose, we used the geochemistry modeling software PHREEQC. The CEMDATA thermodynamic databases were used to supplement the default PHREEQC database with missing mineral phases involved in cement hydration. For our simulations, initial data include formation water compositions, formation mineral fractions, clinker phases fractions and downhole conditions. The thermodynamic process of solids precipitation was then simulated for each of the base cases, then at various conditions. The obtained simulation results include phase assemblage at equilibrium for each case. From a well integrity perspective, predicted phase assemblage of the cement sheath allows for tailored cement degradation analysis on a well-to-well basis when activated by carbonic acid. In addition, the phase assemblage can be used in combination with time-dependent diffusivity and convection models for higher precision characterization. |
, Mohamed Lamine Malki 
, Ilyas Mellal 
