Carbon Accounting for Carbon Dioxide Enhanced Oil recovery

Abstract

It is recognised from currently operating CO2EOR projects that the operations and processes involved in CO2EOR are energy intensive and may compromise the overall carbon footprint of a project (ARI, 2009; Dilmore, 2010). This study intends to provide a medium to high level life cycle assessment of CO2EOR operations for a theoretical offshore North Sea project. The study will focus on upstream operations involved in the CO2 EOR process and aims to quantify all significant processes and activities that contribute to a projects carbon footprint. An attempt will also be made to incorporate the impact of new infrastructure on the carbon inventory of the project. Alongside quantifying the emissions related to operating a CO2 EOR project the study aims to assess the performance of a realistic offshore CO2EOR operation with regard to both incremental oil produced and CO2 stored. Although this performance is relatively well characterised for onshore US projects, it may vary significantly for the currently unproven offshore environment. Considering the uncertainties involved in operating a CO2EOR project in an offshore environment a number of scenarios will be modelled to assess how parameters such as the utilization factor ('barrels of oil produced per tonne of CO2 injected') will affect the overall carbon budget of a project. By modeling a theoretical offshore North Sea CO2EOR project the study intends to both assess the climate benefits / penalties of the project as both a CO2 storage mechanism and as an oil producer. An attempt will be made to assess the merits of such a proposed integrated project against standalone CO2 storage in saline aquifers and oil produced through alternative processes.