NEW ORLEANS – Shell’s Perdido spar development in the Gulf of Mexico is going into its second year of production, and lessons still are being learned. Speaking at the 2011 Deep Offshore Technology Conference & Exhibition, Chris Smith, Perdido Operations Manager, Shell International Exploration & Production Inc., said the project appears to be moving toward its target production after a period of learning for Shell.
There are points of good news along with points of contention, said Smith. While technical issues with the subsea boosting system and delays from the Macondo moratorium held back the project, the wells and reservoir are better than expected and the electric submersible pumps are working better than anticipated.
The biggest single issue to production has been liquids carry over. While the ESPs are working well, the liquids carry over is larger than that designed for. This means more liquids are getting to the surface in the gas stream and the surface separator did not have sufficient capacity to handle the slugs. That meant the flowline separator was overwhelmed on occasion.
The solution, Smith said, was a short-term bypass of the flowline separator coupled with active management of the gas riser hydraulics while repiping the production separator to increase its capacity. In the last two weeks following that fix, the Perdido spar has achieved record production.