Piltun Astokhskoye

Project Overview

The Piltun-Astokhskoye oil project involves the development and production of oil hydrocarbons from the Piltun-Astokhskoye field, which is part of the Sakhalin II Production Sharing Agreement (PSA). The project is managed and operated by Sakhalin Energy Investment Company Ltd. (SEIC), a joint venture between Shell (25%), Mitsui (12%), Mitsubishi (12%), and Gazprom (50% + 1 share).

Fields and Platforms

The project focuses on the development of the Piltun-Astokhskoye field, which is primarily an oil field, although it also produces associated gas.

• Piltun-Astokhskoye-A (PA-A) Platform: This platform, also known as the Molikpaq, is an Arctic offshore drilling unit that was originally operated in the Beaufort Sea. It forms the central feature of the Vityaz Production Complex and has been producing oil since July 1999. The Molikpaq is linked to a Single Anchor Leg Mooring (SALM) buoy and the Okha Floating Storage and Offloading (FSO) vessel for oil transportation.

• Piltun-Astokhskoye-B (PA-B) Platform: This is a drilling, processing, and production platform with a four-legged concrete gravity base substructure (GBS). It was constructed by Aker Kvaerner Technology and Quattrogemini, and production began in the first quarter of 2007. The PA-B platform has a capacity to produce approximately 70,000 barrels of oil per day (11,130 cubic meters per day) and 100 million standard cubic feet of gas per day.

Infrastructure and Pipelines

• Offshore Pipelines: The project includes several offshore pipelines connecting the platforms to the shore. These include pipelines from the PA-B and PA-A platforms, as well as from the Lunskoye gas field. The overall length of the offshore pipelines is approximately 165 kilometers.

• Onshore Pipelines: The oil and gas produced are transported via two 800-kilometer onshore pipelines to Prigorodnoye, located at the south of Sakhalin Island. One pipeline is for oil and the other for gas. These pipelines lead to an Oil Export Terminal (OET) and an LNG plant.

Onshore Processing Facility (OPF)

The OPF is located off the northeast shore of Sakhalin Island and plays a crucial role in processing the gas and condensate received from the Lunskoye field, as well as oil and gas streams from the Piltun-Astokhskoye platforms. The facility includes:

• A 100 Mega Watt power plant to generate power for the OPF and the Lunskoye platform.
• Capabilities to process 51 million cubic meters of gas per day (1,800 million standard cubic feet) and about 60,000 barrels of condensate/oil per day (9,500 cubic meters per day).
• Antifreeze addition to prevent freezing, which is then removed and recycled.
• Modern fire safety equipment and compliance with all required safety and environmental standards.

Environmental and Safety Considerations

The project has been designed with significant environmental and safety considerations in mind:

• The Molikpaq platform was refurbished to withstand the ice conditions and severe weather of the Sea of Okhotsk.
• Environmental Impact Assessments (EIAs) were conducted, including public consultations and expert reviews, to ensure compliance with Russian environmental regulations.
• Measures such as the use of oil-based drilling muds on an intermittent basis, recirculation of muds, and reinjection of wastes and cuttings into the formation were implemented to minimize environmental impact.

Production and Export

• Oil Production: The project has been producing oil since July 1999, with over 60 million barrels of oil produced and exported from the Vityaz complex by the early 2000s. The PA-B platform increased the production capacity significantly once it became operational in 2007.
• Export: The oil is transported via the onshore pipelines to the Oil Export Terminal (OET) at Prigorodnoye, where it is loaded onto tankers for export. The gas is processed into LNG at the LNG plant located at the same site.

Economic and Social Impact

The Sakhalin II project, including the Piltun-Astokhskoye oil field development, represents the largest single foreign direct investment project in Russia. It has significantly contributed to Russia's crude oil production and exports, promoted economic development of Sakhalin Island, and introduced modern and environmentally sound offshore oil production techniques in the Russian Federation.

Project Timeline

• Phase 1: Began in the late 1990s with the first crude oil production in July 1999.
• Phase 2: Included the construction and commissioning of the PA-B platform, starting in the fourth quarter of 2003 and beginning production in the first quarter of 2007.
• Full Operational Status: The Onshore Processing Facility (OPF) became fully operational in 2008, marking the completion of the major phases of the project.