Tordis IOR (improved oil recovery) consists of two phases:

  • The necessary platform modifications on Gullfaks C in order to change to low-pressure production were made in phase 1. Increasing the oil recovery by some 16 million barrels, this phase was implemented in 2006.
  • Phase 2 comprises the subsea separation station in 2007. The production increases by some 19 million barrels of oil. 19-meter high, 40-meter long, 25-metre wide, the subsea template weighs 1250 tonnes.

Located in the Tampen area west of Bergen Tordis came on stream in 1994. After many years of operation the energy (pressure) in the reservoir has dropped and in addition the water content in the produced liquid has increased.

The reduced energy is thus used for transporting great volumes of superfluous liquid.           
  
Water and sand are separated from the well stream close to the reservoir and injected into a subsea formation for storage.                 

In addition a multi-phase pump helps send oil and gas through a 10-kilometre pipeline to Gullfaks C for processing, storage and export.

Optimising the use of energy, this solution is also environmentally friendly as it reduces the volume of produced water discharged into the sea.

These solutions may also enhance the production from:

  • small fields
  • deep-water discoveries
  • remote fields without any existing infrastructure

In addition they may help maintain tail production and open for development in environmentally sensitive areas.

Technical and operational challenges:

  • simple, safe and effective operation of the process plant
  • it must be possible to retrieve and replace or repair critical modules quickly and effectively
  • it must be possible to maintain production independently of the processing plant     
  • power transmission system
  • continuous monitoring of sand and water production
  • multi-phase metering on the production pipeline.