Building the Case for Raw Seawater Injection Scheme in Barton

Abstract Shell Malaysia Exploration & Production (SM-EP) is planning for secondary recovery via water injection in the Barton field by using the novel concept of raw seawater injection. Raw seawater injection is essentially injection of minimally treated, fully aerated seawater. The seawater having undergone limited solids interception only by coarse filtration. The concept of raw seawater injection has not received much interest from operators due to lack of understanding on issues such as reservoir souring and impact of oxygen on the reservoir. However, raw seawater injection has proven to be the most cost effective secondary recovery design for mature fields like Barton, which do not boast huge reserves. This paper will focus on work carried out to identify and mitigate additional risks from raw seawater injection, principally on issues of reservoir souring, increased corrosion on production system, increased levels of suspended solids and impact of oxygen on the reservoir scale. Raw seawater injection in Barton will be the first of its type in the Shell Group and only the second known attempt in the industry.