Influence of CO2 impurities on Enhanced Oil Recovery (EOR) in conventional oil reservoirs

About the Project

The application of CO2 injection for Enhanced Oil Recovery (EOR) has proven to be an effective technique for increasing oil recovery from mature reservoirs. However, the presence of CO2 impurities—such as nitrogen (N2), methane (CH4), hydrogen sulphide (H2S), and water—may significantly influence the thermodynamic and fluid flow properties, thereby impacting recovery efficiency. This research proposes a comprehensive numerical modelling and simulation study to evaluate the effects of CO2 impurities on the key mechanisms of CO2-EOR. We will develop a set of integrated models to simulate the interactions between CO2, impurities, and reservoir fluids. This includes:

1. thermodynamic models to predict the phase behaviour and miscibility of CO2 mixtures with varying impurity concentrations
2. compositional modelling to simulate the dynamic displacement of oil by CO2 mixtures in porous media
3. multi-phase flow simulations to evaluate the effects of impurities on reservoir fluid mobility, pressure, and displacement efficiency.

The study will explore a range of impurity concentrations, examining their effects on key parameters such as CO2 solubility, oil recovery factor, interfacial tension, and capillary pressure. Additionally, a sensitivity analysis will be performed to assess the impact of impurity-induced changes in reservoir rock wettability and permeability on the overall EOR process. The simulation results will provide critical insights into the role of CO2 impurities in modifying reservoir performance and guide the development of optimised CO2 injection strategies. This work will not only address the challenges posed by impurities but also offer practical recommendations for improving CO2-EOR efficiency in the context of impure CO2 sources.

How to apply

Formal applications can be submitted via the University of Bradford web site; applicants will need to register an account, select 'Postgraduate Research' as the course and then use the keywords 'chemical engineering'. Applicants should then specify the project title in the 'Research Proposal' section.

Funding Notes

This is a self-funded PhD project; applicants will be expected to pay their own fees or have a suitable source of third-party funding. UK students may be able to apply for a Doctoral Loan from Student Finance for financial support.

References

1. Jin, L. et al., 2017, Impact of CO2 Impurity on MMP and Oil Recovery Performance of the Bell Creek Oil Field, Energy Procedia, vol 114, p. 6997-7008, doi.org/10.1016/j.egypro.2017.03.1841.
2. Lee, H.S, et al., 2021, Compositional Modeling of Impure CO2 Injection for Enhanced Oil Recovery and CO2 Storage, doi.org/10.3390/app11177907.
3. Zhang, P.Y, et al, 2004, Effect of CO2 Impurities on Gas-Injection EOR Processes, Paper Number: SPE-89477-MS, doi.org/10.2118/89477-MS.