South Arne oil and gas field

The South Arne (Danish: Syd Arne) field is a major crude oil and associated gas production field in the Danish sector of the central North Sea. Production of oil and gas started in 1999, and peak oil and gas was in 2000.

The field
The characteristics of the South Arne field reservoir are as follows.

Owners and operators
The field was originally owned jointly by Hess 57.48%; DONG 34.58%; Noreco 6.56%; and Danoil 1.58%. It was operated by Hess. In 2021 Hess Denmark sold its interests in South Arne to Ineos E&P for $150 million.

Infrastructure
The field was initially developed through a single offshore installation (SA), two further field installations (WHPE and WHPN) were commissioned in 2013. Details are summarised below.

The subsea oil tank has a capacity of 87,000 m3 (547,230 barrels). It is 110 m by 90 m by 18 m high. The single anchor leg mooring (SAL) is located 2 km (56.09247°N 4.25615°E) from the South Arne installation.

Hejre tie back
There are plans to tie-in the Hejre platform into South Arne WHPE. This would be via a 30 km 10-inch or 12-inch multiphase pipeline. South Arne has sufficient capacity to process the Hejre fluids.

Production
Production facilities comprise a single three-stage oil/gas/water separator train capable of processing 50,000 barrels of oil per day (8,065 m3/day), 2 million m3 of gas per day, and 100,000 barrels of water per day (16,129 m3/day), The gas compression is a single four-stage train.

Production from the South Arne field is aided by water injection for pressure support. Some produced water is injected into the reservoir, the remainder is treated and discharged overboard. Injection water is treated to remove sulphate ions prior to injection.

The oil and gas production profile of the South Arne field is as shown in the tables.