Tyra Field

Tyra Field
Platform at Tyra East
CountryDenmark
RegionNorth Sea
Block5504/11
5504/12
Offshore/onshoreoffshore
OperatorTotal
PartnersTotal
Noreco
Nordsofonden
Field history
Discovery1968
Start of production1984
Production
Current production of gas237.8×10^6 cu ft/d (6.73×10^6 m3/d)
Estimated gas in place1,250×10^9 cu ft (35×10^9 m3)
Producing formationsDanian and Upper Cretaceous Chalk

Tyra Field is the largest gas condensate field in the Danish Sector of the North Sea.[1] It was discovered in 1968 and production started in 1984.[2] The field is owned by Dansk Undergrunds Consortium, a partnership between Total, BlueNord and Nordsofonden, and operated by Total.[3] The reservoir depth is about 2,000 metres (6,600 ft) and it covers area of 90 kilometres (56 mi) in the water depth of 37–40 metres (121–131 ft).[2] The Tyra field has a number of satellite fields, including Roar, Svend and Tyra Southeast fields.

History

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In August 2017 Maersk Oil was sold to Total S.A. with the takeover completed in 2018.

Facilities

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The Tyra Field has two production complexes named Tyra West and Tyra East, connected by pipelines. Tyra West includes oil and gas processing plants which in addition to the gas produced at the Tyra field, processes also gas from Halfdan field and the Valdemar oil field. The complex consists of two wellhead platforms, one processing and accommodation platform, and one gas flare stack. Tyra East processes also oil and gas from Valdemar, Roar, Svend, Tyra Southeast, Harald gas field, Lulita, Gorm and Dan oil fields. It consists of two wellhead platforms, one processing and accommodation platform, one gas flare stack, and one riser platform.[2]

The installations developed for the Tyra field were:[4]

Tyra field installations
Installation Location Block Platforms Function Type Legs Well slots Installed Production start Production to
Tyra West 6.2 TW-A Processing (2 x 135 MMSCFD) Steel jacket 4 March 1982 May 1984 TE-E
TW-B Drilling & wellhead Steel jacket 4 12 March 1982 May 1984 TW-A
TW-C Drilling & wellhead Steel jacket 4 12 May 1983 1985 TW-A
TW-D Flare Steel jacket 3 April–May 1983
TW-E Production Steel jacket 1984
Tyra East 6.2 TCP-A Processing (2 X 135 MMSCFD) & accommodation Steel jacket 8 March–June 1983 June 1984 TE-E
TE-B Drilling & wellhead Steel jacket 4 12 February 1983 1982 June 1984 TCP-A
TE-C Drilling & wellhead Steel jacket 4 12 May 1983 1985 TCP-A
TE-D Flare Steel jacket 3 April–May 1983
TE-E Riser Steel jacket 4 March 1982 1984 Jutland onshore
TE-F Production Steel jacket 1995

In total, the field has 20 gas-producing wells, and 28 oil and gas-producing wells.[2]

Fluids from the drilling & wellhead platforms are routed to an inlet three phase inlet separator on the ‘A’ processing platforms. The separator separated the fluids into gas, condensate and produced water. Gas undergoes water dehydration through contact with glycol. On TCP-A the gas is comingled with gas from Gorm, Dan and Tyra West. The combined gas stream is chilled to achieve a hydrocarbon dewpoint. The gas is compressed from 1000 to 2000 psi (pounds-force per square inch) in 5 Ruston TB5000 gas turbine driven gas compressors (24,500 brake horse power total), and is fiscally metered before export onshore to Jutland. The design export rate is 11.5 million cubic metres (405 million cubic feet) per day at standard conditions.[4]

Condensate from the inlet separator is routed to a coalescer after which it is comingled with condensate from Tyra West. The combined stream is routed successively through a 1st stage, 2nd stage and 3rd stage separators operating at successively lower pressures. Gas from the 2nd and 3rd stage separators is compressed and joins the gas from the 1st stage separator and is routed into the inlet separator. Condensate from the 3rd stage separator is fiscally metered and is exported onshore via the Gorm installation. The design export rate is 20,000 barrels/day.[4]

Produced water from the inlet separator is treated to remove and condensate and is discharged overboard.[4]

Produced oil is transported to the Gorm E riser platform in the Gorm field, and further through the subsea pipeline to the oil terminal in Fredericia, Denmark. Produced natural gas is transported from the Tyra East riser platform to Nybro Gas Processing Plant, Denmark, and from Tyra West riser platform to the Netherlands through the Tyra West – F3 and NOGAT pipelines.[5]

Redevelopment project

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Due to the production facilities having sunk 6m Maersk Oil announced on 1 December 2017 Maersk Oil the redevelopment of Tyra Field, which would mean decommissioning the 35 year old facilities and installing new ones.[6][7] The living and processing platform on Tyra East and Tyra West will be scrapped. One new living platform and one new processing platform will be built. The living quarter platform will be constructed by Italian EPC contractor Rosetti marino, while processing platform will be constructed in Kuala Lumpur by American EPC contractor McDermott International.

In July 2018 Modern American Recycling Services based in Frederikshavn secured a contract to scrap the two platforms.[8]

Up until the temporary closure in September 2019, the Tyra field processed 90% of all gas produced in the Danish part of the North Sea.[needs update][6]

The decommission project is estimated to cost 4 Billion DKK and the new facilities will cost 17 Billion DKK. All in all the project is expected use 1.3 million working hours.[9]

The new facilities were planned to be ready for production in July 2022, but this was postponed to July 2023 due to the COVID-19 pandemic.[9]

Tyra field satellites

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The Tyra field has a number of satellite fields. These include Roar, Svend and Tyra Southeast fields.

The characteristics of the satellite fields are as follows.[10]

Field Roar Svend Tyra Southeast
Prospect Bent North Arne / Otto
Reservoir Chalk Chalk Chalk
Geological age Danian and Upper Cretaceous Danian and Upper Cretaceous Danian and Upper Cretaceous
Coordinates 55.767485°N 4.64839°E 56.178324°N 4.179324°E 55.639618°N 4.882641°E
Block 5504/7 5604/25 5504/12
Reservoir depth 2,025 m 2,500 m 2,050 m
Field delineation 84 km2 48 km2 142 km2
Reserves Oil 0.1 million m3

Gas 1.7 billion Nm3

Oil 0.5 million m3

Gas 0.1 billion Nm3

Oil 7.7 million m3

Gas 16.5 billion Nm3

Discovered 1968 1975 North Arne, 1982 Otto 1992

The Roar, Svend and Tyra Southeast fields are developed through three offshore installations as shown.[10] [11]

Field Roar Svend Tyra Southeast
Production start 1996 1996 2002
Water depth 46 m 65 m 39 m
Installation Steel STAR platform Steel STAR platform Steel STAR platform
Function Wellhead, separation Wellhead Wellhead, separation
Substructure weight tonnes 950 1150 880
Topsides weight tonnes 550 575 550
Number of wells 4 gas 4 2 oil, 5 gas
Status Closed 2019 Closed 2015 Closed 2019
Export, well fluids 11 km 16-inch multiphase pipeline to Tyra East pipeline to Tyra East pipeline to Tyra East

The oil and gas production profile of the Roar, Svend and Tyra Southeast fields is as shown.

Roar, Svend and Tyra Southeast oil production (1000 m3) 1996-2010[12]
Year 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010
Roar 320 427 327 259 285 317 175 121 98 94 51 35 28 30 24
Svend 836 1,356 635 521 576 397 457 280 326 324 296 299 278 195 190
Tyra Southeast 493 343 580 614 446 377 429 374 225
Roar, Svend and Tyra Southeast oil production (1000 m3) 2011-2022[12]
Year 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Total
Roar 16 2 4 6 6 8 82 100 76 2,891
Svend 145 171 183 160 136 7,759
Tyra Southeast 165 148 98 91 118 283 383 316 162 5,644
Roar, Svend and Tyra Southeast gas production (million normal m3) 1996-2010[12]
Year 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010
Roar 1,332 1,964 1,458 1,249 1,407 1,702 1,052 915 894 860 489 367 417 398 213
Svend 85 152 84 65 75 48 61 43 38 34 28 28 24 16 27
Tyra Southeast 447 452 1,233 1,337 1,108 848 889 939 911
Roar, Svend and Tyra Southeast gas production (million normal 1000 m3) 2011-2022[12]
Year 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Total
Roar 171 24 28 46 40 46 264 278 194 15,809
Svend 24 27 20 16 15 908
Tyra Southeast 626 610 306 201 248 554 981 734 391 12,816

See also

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References

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  1. ^ Glennie, K. W. (1998). Petroleum geology of the North Sea: basic concepts and recent advances. Wiley-Blackwell. p. 343. ISBN 978-0-632-03845-9.
  2. ^ a b c d "Oil and Gas Production in Denmark 07. Appendix B: Producing Fields". Danish Energy Agency. Archived from the original on 2012-11-30. Retrieved 2011-01-15.
  3. ^ "Tyra Gas Field Starts its Redevelopment | Exploration & Production". Archived from the original on 2020-10-25. Retrieved 2020-01-24.
  4. ^ a b c d Oilfield Publications Limited (1985). The North Sea Platform Guide. Ledbury: Oilfield Publications Limited. pp. 663–78.
  5. ^ International Energy Agency (2006). Energy policies of IEA countries: Denmark 2006 review (PDF). OECD. p. 146. ISBN 978-92-64-10971-1.
  6. ^ a b Wittrup, Sanne (1 December 2017). "Største Nordsø-investering nogensinde: Tyrafelt ombygges for 21 mia. kroner". Ingeniøren (in Danish). Retrieved 22 January 2019.
  7. ^ "Tyra Gas Field Redevelopment". Offshore Technology. Retrieved 2021-09-06.
  8. ^ "Merry Christmas and Happy New Year". Port of Frederikshavn. 2018-12-19. Retrieved 2019-01-22.
  9. ^ a b "Efter milepæl på Tyra begynder nu jobfest i Nordsøen med arbejde til flere hundreder". JydskeVestkysten. Retrieved 2021-09-06.
  10. ^ a b OSPAR. "OSPAR Inventory of Offshore Installations - 2021". Retrieved 17 November 2023.
  11. ^ "Oil and gas production in Denmark 2013" (PDF).
  12. ^ a b c d "Monthly and yearly production". 15 August 2016. Retrieved 17 November 2023.