Offshore Oil and Gas Production in Russia
The Sakhalin-1 project involves the development of three offshore fields: Chaivo, Odoptu, and Arkutun-Dagi, located in the Sea of Okhotsk on Sakhalin Island’s north-eastern continental shelf.
State-of-the-art technologies and project management methods are used to develop the fields. At the Odoptu field, oil is produced from an onshore site using super-extended reach horizontal wells. At the Chaivo field, oil is extracted from an onshore site and the Orlan platform using wells with record-length boreholes, while the Arkutun-Dagi field is developed using a unique drilling platform, Berkut.
The oil from the Sakhalin-1 project fields is delivered to the Chaivo onshore oil treatment facility on Sakhalin Island and then transported by pipeline to the De-Kastri oil export terminal in the Khabarovsk Territory.
In 2017, Rosneft, acting as part of the Sakhalin-1 consortium, successfully completed drilling of the world’s longest well from the Orlan platform at the Chaivo field in the Sea of Okhotsk. The length of the well including a horizontal completion is 15 thousand meters, a current world record. The well is classified as a supercomplex well, with DDI (directional drilling index) of 8.0 and a step-out of 14,129 m.
In 2017, we started Phase 2 development of the Odoptu-Sea field by drilling a production well from a new onshore drilling rig called Krechet.
The Krechet rig was specifically designed to drill extended reach wells. The rig was uniquely designed to operate in challenging climatic conditions (at temperatures below –40oС and in seismic zones).
The design of the Krechet drilling rig is much similar to that of the Yastreb rig, which was used in the Sakhalin-1 project and was responsible for drilling some of the world’s longest wells. Unlike Yastreb, the Krechet rig offers enhanced mobility which provides for its wider use in development drilling at the Odoptu-Sea field.
NORTHERN TIP OF THE CHAIVO FIELD
Under the license obtained by Rosneft, the Company has been developing the northern tip of the Chaivo field situated in shallow waters off the north-eastern coast of Sakhalin Island, since September 2014. The Company commissioned and put into operation permanent oil gathering and metering systems ahead of the schedule for construction of onshore production facilities.
Oil production at the northern tip of the Chaivo Field involves five wells that have a unique, complex design and extended reach. The wells are equipped with high-tech completion systems comprising inflow control devices to minimize gas breakthroughs and maximize cumulative oil production.
In 2017, actual oil production was 1.4 mmt, with gas supplies to consumers totalling 0.2 bcm.
THE LEBEDINSKOYE FIELD
The Lebedinskoye field (in the Sea of Okhotsk) began oil production in 2014 and is operated by LLC RN-Sakhalinmorneftegaz. Four production wells are used to pump the oil. The oil extracted at the Lebedinskoye field has a quality grade similar to Sokol crude.
In 2017, the Company carried out a project to further delineate the boundaries of the Lebedinskoye field, which expanded its area and the field’s resource base. In addition, the Lebedinskoye Field – Odoptu-Sea Field pipeline was launched to improve operational reliability.
In 2017, actual production from the field was 332 thousand tonnes of oil and approximately 25 mmcm of natural gas.
ODOPTU-SEA FIELD (NORTHERN DOME)
The Odoptu-Sea field (the Northern Dome) is Russia’s first offshore field, flowing oil since 1998. LLC RN-Sakhalinmorneftegaz is the field operator producing oil and gas at the Odoptu-Sea.
Oil is produced from horizontal wells operated from the shore of the island. A total 40 extended reach production wells with lengths of 5–8 km have been drilled. As at 1 January 2018, 28 oil production wells and seven injection wells were in operation. Actual production in 2017 was 371 thousand tonnes of oil and 128 mmcm of natural gas.
Oil and gas gathering and treatment facilities, reservoir pressure maintenance system, outbound pipelines to transport oil, gas, and water, and power generation facilities were constructed as part of the field setup.