Lloyds List: Sakhalin II embarks on year of milestones

Martyn Wingrove, Lloyds List
Published: Jul 17, 2007

GAZPROM, Shell and Japanese investors have passed several milestones in the Sakhalin II project that will ensure oil and liquefied natural gas exports can begin by late 2008.

Sakhalin Energy Investment, which operates the $20bn integrated oil and liquefied natural gas project, said 2007 will be a pivotal year in bringing the project on stream.

‘Key milestones this year include the commissioning of Russia’s first LNG plant, installation of the PA-B topsides and commissioning of the pipelines,’ said Sakhalin Energy’s chief executive Ian Craig.

In one of the largest offshore operations, Sakhalin Energy has mated the top of the PA-B platform to the concrete legs over the Piltun-Astokhskoye field, which is off the northeast coast of Sakhalin Island in the Sea of Okhotsk.

Sakhalin Energy broke its own world record by installing 28,000 tonnes of topsides including the processing, accommodation and drilling units on to a concrete gravity base structure in one lift.

A specialised T-shaped barge was built to transport the 28,000 tonne topsides 3,000 km from a South Korean fabrication yard to the PA-B site.

The 190 m long, 92 m wide barge then deployed and ‘mated’ these topsides to the foundations in a process known as a float-over.

The barge moved between the concrete legs, floating the topsides over the base structure. It was then ballasted down so the topsides were slowly lowered to sit on the legs.

Leg mating units were originally built into the four platform legs to absorb the shock of the initial contact and to ensure the topsides were a perfect fit.

Sakhalin Energy set the old topsides weight record last year when the topsides of the Lunskoye A platform, located south of PA-B, were floated over and installed on a concrete gravity base structure.

‘We have once again extended the envelope for the offshore float-over installation technique,’ said Sakhalin II project director Jaap Huijskes.

Now the topsides are linked to the base structure, the next phase for Sakhalin Energy is to commence hook-up and commissioning operations, to ensure all systems work properly before oil production begins next year.

The PA-B platform, which is now 121 m high from the seabed to the top of the drilling derrick, is part of the second phase of developing the Piltun-Astokhskoye oil field. The first phase is already producing oil during the summer months via the Vityaz complex.

The platform is expected to come on stream next year, with oil being pumped to a tanker export terminal at Prigorodnoye near Korsakov in the south of Sakhalin Island.

Another part of the Sakhalin II project is the development of the offshore Lunskoye gas field and construction of an onshore liquefied natural gas terminal, also in the southern part of the island. Commissioning operations at the Prigorodnoye LNG plant started after Golar’s 2006-built LNG carrier Granosa delivered a 135,000 cu m cargo to the new jetty in Aniva Bay.

This is the first of two cargoes that are required to test the facilities. Sakhalin Energy needed to obtain a special order from the Russian government to allow a foreign tanker to import the cargoes.

In other operations, development drilling work has just started on the Lunskoye platform, also in the Sea of Okhotsk. This is the first gas production well to be drilled anywhere offshore Russia.

‘Drilling of the first wells from Lunskoye platform is a major development milestone. Lunskoye will provide the main volume of gas for LNG production,’ said Mr Craig.

The plan is to drill two wells this year, one for the reinjection of the drill cuttings and another for gas production.

Drill cuttings from the wells will be reinjected, instead of being dumped into the marine environment or being transported by barge back to an onshore landfill site.

Overall there will be 14 wells drilled from the Lunskoye platform, including 11 gas producers. There will be a well for injecting produced water and one for appraising the oil rim that is associated with the gas field.

The Lunskoye platform will operate with zero drilling discharges to the environment, so neither drilling waste nor drilling mud, used to lubricate the drilling systems and transport the rock to the surface, will be discharged overboard. A similar policy will be implemented on the PA-B platform. Meanwhile, the first phase of Sakhalin II restarted its ninth oil production season early in June at the Vityaz complex on the Astokh field.

Oil is processed on the Molikpaq platform and sent to the Okha storage and offloading vessel, which is used for exporting crude to tankers

A 2004-built, 108,000 dwt ice-class tanker Governor Farkhutdinov has been chartered from Primorsk Shipping this year to take crude cargoes to Asian terminals.