Teething problems for North Sea Valhall stimulation technique

Oct. 19, 2018
Aker BP has tested a new well stimulation method as part of a drilling campaign at the Valhall IP platform in the southern Norwegian North Sea.

Offshore staff

LYSAKER, NorwayAker BP has tested a new well stimulation method as part of a drilling campaign at the Valhall IP platform in the southern Norwegian North Sea.

The company hopes the technique will cut the time and cost of drilling new wells; however, testing has taken more time than anticipated due to technical issues.

In August the first new IP well came onstream, several months behind plan. The second well is currently undergoing conventional stimulation and should enter production during the current quarter.

After completing a P&A campaign at Valhall earlier this month, thejackupMaersk Invincible will now perform drilling elsewhere on the field.

Work on the newValhall Flank West normally unmanned installation is progressing as planned. Engineering has finished of the topsides and jacket, with the current focus on supporting topsides construction in Verdal, Norway.

The new Valhall Flank North Water Injection project is designed to expand water injection capability to the field’s northern drainage area, introducing water injection to existing depleted areas and offering a potential to recovery a further 7.8 MMboe from the reservoir.

Drilling should start in the current quarter with water injection beginning next spring, when the pipelines and risers have been installed. Total investment is around $100 million.

Subsea 7 is responsible for flexible riser and pipeline installation, with Aker Solutions performing modifications on the Valhall North Flank NUI and on the Valhall field center.

Another ongoing Aker BP program in the southern Norwegian sector is at the Tambar field, a satellite to Ula, targeting extra reserves of 27 MMboe and at the same time extending the field’s productive lifespan through 2028.

This involves drilling two new wells, both recently onstream, and gas lift, due to start operating in 2Q 2019, pending completion of the remaining facilities modifications.

Production from the Ivar Aasen field to the north dipped recently due mainly to lower gas exports. However, new water injectors drilled earlier this year have improved the ability to control reservoir pressure development, Aker BP said, allowing for improved drainage control and a higher oil/gas ratio.

Finally, the company’s Skarv FPSO in the Norwegian Sea has experienced problems with the gas injection system which led temporarily to higher gas export than normal. After gas injection was increased to re-pressurize the affected reservoir segments, gas exports were below normal during 3Q.

One of Skarv’s wells remains shut in due to x-mas tree issues. A newly developed in situ repair method will be tested soon.

10/19/2018