South Arne oil and gas field | |
Coordinates: | 56.07835°N 4.22886°E |
Country: | Denmark |
Region: | North Sea |
Locblocks: | 5604/29 &30 |
Offonshore: | Offshore |
Operators: | Hess (until 2021), Ineos (since 2021) |
Owner: | Hess; DONG; Noreco; and Danoil (initially); Ineos (since 2021) |
Start Production: | 1999 |
Peak Production: | 2,558,000 cubic metres oil/year |
Producingformations: | Chalk |
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 characteristics of the South Arne field reservoir are as follows.[1]
Field | South Arne | |
Reservoir | Chalk | |
Geological age | Danian and Upper Cretaceous | |
Offshore Block | 5604/29 &30 | |
Reservoir depth | 2,800 m | |
Reservoir pressure and temperature | 434 bar and 90°C. | |
Field delineation | 93 km2 | |
Reserves | Oil 12.9 million m3 Gas 2.6 billion Normal m3 | |
Discovered | 1969 |
The field was originally owned jointly by Hess 57.48%; DONG 34.58%; Noreco 6.56%; and Danoil 1.58%.[2] It was operated by Hess. In 2021 Hess Denmark sold its interests in South Arne to Ineos E&P for $150 million.
The field was initially developed through a single offshore installation (SA), two further field installations (WHPE and WHPN) were commissioned in 2013.[3] Details are summarised below.
South Arne (SA) | WHPE Wellhead platform East (SA WHPE) | WHPN Wellhead platform North (SA WHPN) | |
Coordinates | 56.07835°N 4.22886°E | 56.07823°N 4.230876°E | 56.09574°N 4.219251°E |
Production start | 1999 | 2013 | 2013 |
Water depth | 60 m | 60 | 60 |
Installation | Concrete gravity base and steel lattice drilling tower | Fixed steel | Fixed steel |
Access | Helicopter | Bridge link to South Arne | Helicopter |
Function | Wellhead, process, accommodation (57 beds) | Wellheads | Wellheads |
Substructure weight tonnes | 112,800 | 2,224 | 2,333 |
Topsides weight tonnes | 8,955 | 1,932 | 1,762 |
Number of wells | 14 oil production, 7 water injection | 12 | 6 |
Export, liquids | To subsea oil storage then by single anchor leg mooring (SAL) to tanker | To South Arne | Pipeline Bundle to WHPE (production P/L, lift gas and water injection) |
Export, gas | 285 km 24-inch pipeline to Nyhro | To South Arne |
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.[4] The single anchor leg mooring (SAL) is located 2 km (56.09247°N 4.25615°E) from the South Arne installation.
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.[5]
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.
Oil | 700 | 1,023 | 1,030 | 946 | 774 | 570 | 565 | 479 | 408 | 347 | 29,802 | |
Gas | 167 | 238 | 307 | 370 | 281 | 187 | 167 | 132 | 108 | 108 | 7,665 |
Oil | 757 | 2,558 | 2,031 | 2,313 | 2,383 | 2,257 | 2,371 | 1,869 | 1,245 | 1,139 | 1,164 | 1,066 | 1,004 | 803 | |
Gas | 167 | 713 | 774 | 681 | 544 | 461 | 485 | 366 | 234 | 225 | 271 | 248 | 238 | 194 |