Adoption of a Process to Prevent Souring Associated with Seawater Waterflooding in the Ursa-Princess Fields, Deepwater Gulf of Mexico

Abstract

Abstract A comprehensive evaluation of the potential for preventing reservoir souring through the use of Sulphate Rejection Membranes (SRM) was made for the Ursa-Princess Waterflood (UPWF), deepwater Gulf of Mexico. The operator, Shell Exploration and Production Company (SEPCO) has long believed that injection of seawater is a precursor to souring; the question is not ‘if’ but ‘when’ souring would occur.1 Metallurgy of the producer well tubing, casing, safety valves and topsides is not consistently sour safe and retrofitting would have rendered the waterflood project economics unviable. Therefore, prevention of souring by SRM was investigated, evaluated and adopted in order to avoid retrofitting the metallurgy. This is the first time that an SRM has been selected by a major operator for a seawater waterflood project based primarily on prevention of souring, while accepting SRM as proven for scale control.