Well system boosts output

December 13, 1999, 08:00 CET

Innovative downhole equipment which Statoil has adopted on Gullfaks C has boosted oil production from the North Sea platform.

The surface-controlled reservoir analysis and management system (Scrams) was installed in the C-29 well during April. Since then, this producer has increased its output from roughly 1,250 barrels per day to 7,500 barrels.

Developed by Halliburton/PES, this system makes it possible to control oil production from several reservoir zones simultaneously. More oil can be recovered because Scrams prevents unwanted water and gas output.

Thanks to the new valves, several zones can be open at the same time and production from these is better regulated. Previously, the discovery that a zone was producing water called for costly and time-consuming work to shut it off.

Scrams makes it possible to do this work in a simple way via a computer in the platform's control room.

The total cost of well recompletion, readying and installing the equipment, plus deferred production during the operational period, came to roughly NOK 100 million.

"This investment was recovered by September," reports Arild Hesjedal, manager of the petroleum technology sector in the Gullfaks operations organisation.

He sees big opportunities for financial gain from adopting Scrams – not least the ability to accelerate production from the Statfjord formation in well C-29 by up to three years.

That can be accomplished because production starts from many zones simultaneously rather than sequentially.

Mr Hesjedal adds that it has already been resolved to install Scrams in a subsea-completed well on Rimfaks – one of Statoil's three Gullfaks satellites – in the summer of 2000. This will represent the first use of such equipment with a subsea well in the North Sea.

Scrams has also been adopted off Norway by Norsk Hydro and Saga Petroleum.