Carbon Capture and Storage and Enhanced Oil Recovery: A Fully Integrated Approach

Hedley, Ben ¹; Aldersey-Williams, John ⁷; Davies, Richard ²; Gluyas, Jon ²; Hanstock, David ⁶; Law, Adam ⁵; Scott, David ⁴; Watson, Francesca ³; Wilson, David ⁵
(1)Earth Science, University of Durham, Durham, United Kingdom. (2) Geoenergy Durham, Durham, United Kingdom. (3) Geospatial Research Ltd, Durham, United Kingdom. (4) GeoPressure Technology, Durham, United Kingdom. (5) ERC Equipoise Ltd, Croydon, United Kingdom. (6) Progressive Energy Ltd, Stonehouse, United Kingdom. (7) Redfield Consulting, Monymusk, United Kingdom.

Carbon capture and storage (CCS) has been widely accepted as a key method of reducing anthropogenic carbon dioxide emissions from industrial processes and energy generation. Furthermore, experience from Texas and Canada have proven the effectiveness of tertiary or enhanced oil recovery (EOR) utilising CO₂ injection. Recent studies in the United Kingdom have indicated the potential for an addition 6 billion bbl of oil that may be produced by CO₂ injection, with on-shore carbon capture projects providing a constant and reliable CO₂ stream, the absence of which has been a key reason why this technology has not been implemented at an earlier stage.

In many cases, there has been a firm division between pure storage of captured CO₂ (e.g. Sleipner, In Salah) and its utilisation for increasing recovery from depleting or difficult oil/gas fields (e.g. Weyburn). In this study, we investigate and appraise the case for a fully integrated approach, utilising pure CO₂ storage in deep saline formations allied to EOR in nearby oil fields, supplied by CO₂ captured from an on-shore coal fired power station.

Working in accordance with the EU directive on storage of CO₂ we examined in detail the geology and petrophysics for the deep saline formation utilising 2D seismic and exploration well data, allied to nearby analogues for inferred rock mechanics, conduct a full pressure study to examine the connectivity and pressure regime of the formation and estimate storage capacity based on differing sub-surface scenarios to form the static model. We dynamically modelled using the Tough 2 simulator; the injection of CO₂ into the formation to assess leakage risk, CO₂ behaviour and operational lifespan.

Furthermore, we re-assessed the previous models for EOR potential of an abandoned oil field to optimise recovery using the fewest wells and deliver the reservoir sweep required to have a material impact on EOR. We examined the production history and previous models to re-define estimates for additional recovery and subsequent CO₂ storage capacity.

With highly encouraging results, this study forms a portion of a submission to government as part of competition 2-4 for a UK CCS demonstration project to be finalised by May 2011 and hope, if accepted, this may remove the division between storage and EOR, something that is vital should the lifespan of the North Sea as a resource be extended.

AAPG Search and Discovery Article #90135©2011 AAPG International Conference and Exhibition, Milan, Italy, 23-26 October 2011.