To this day, Brent is still one of the largest oil and gas fields ever developed in the world and the structures required to unlock its energy reflect that. The Sleipner A platform produces oil and gas in the North Sea and is supported on the seabed at a water depth of 82 m. It is a Condeep type platform with a concrete gravity base structure consisting of 24 cells and with a total base area of 16 000 m2. Disclosure statement Hebron operators have supported … The field was first discovered in 1980, and is located offshore Newfoundland and … PLATFORM TIMELAPSE VIDEO. Extreme wide aerial view of workers dressed in safety gear aboard the platform topside, guiding components which are being hoisted off the platform via a pulley system. Cutting and removing the upper portion of the concrete legs would be technically challenging and very costly. As you may appreciate, making a cut without trapping that wire with 6,000 tons of dead weight bearing down on that cut surface, in a marine environment where you're dealing with the effects of waves, wind, a dynamic situation, is certainly extremely challenging. John Gillies / Brent Decommissioning Execution Manager. The location of the remaining structure would be clearly marked on charts and documented in FishSAFE, a database that helps fishermen avoid oil and gas structures in UK waters. by their own massive weight. These gravity base structures are made of heavily reinforced concrete. An outline of the gravity base structure is seen anchored to the bottom of the seabed. These cells are 60m in height, up to 20m in diameter, with concrete walls almost 1m thick. Side view of a vessel moored in the harbour, buildings in the background, and glistening waters and sea birds in the foreground. Although removing the GBS would support jobs, these would only be on a short-term basis. Mid front view of Katy typing on her laptop while James, seated next to her, looks on. Each trial used a test piece of concrete that was designed to replicate the concrete geometry and was scaled to a ratio of 1:20 to the GBS. For the Brent structures to be removed they would have to be detached from the seabed, floated to the surface and towed to shore for dismantling in a deep-water inlet or fjord. Briefly, gravity-based platforms take advantage of the large size and heavy mass to support large facilities in water depths of up to 1,000 ft. Close-up in profile of a seated John Gillies, panning up to the man leaning alongside him. PREV. …that would indicate that we would have at least one fatality per Gravity Base Structure being refloated. Close-up of Alistair Hope as he speaks, seen against the slightly out of focus background of an office environment. Close-up of a screen displaying infographics related to the base structures a finger pointing to one of the graphics. Close-up of Duncan Manning as he speaks, seen against the slightly out of focus background of an office environment. The Sleipner A platform produces oil and gas in the North Sea and is supported on the seabed at a water depth of 82 m. It is a Condeep type platform with a concrete gravity base structure consisting of 24 cells and with a total base area of 16 000 m 2. [Video footage] Low angle footage of an oil platform, planted atop very tall … And while the final costs of decommissioning are not yet known, Brent will remain an overwhelmingly positive contributor to the UK treasury. The concrete gravity oil storage base concept was selected due to the insufficient capacity of the Danish oil … For example, the base of a concrete gravity platform built for Mobil Oil in the North Sea consists of 19 hollow concrete cylinders of 2 ft wall thickness, 66 ft inner diameter, and 164 ft height. For multiple selection of entities keep "SHIFT" key pressed. On an offshore oil platform, topsides is the upper part of the structure which include the processing facilities and often accomodation space. Signatories to the convention agree to specific rules designed to limit the impact of human activity on the marine environment of the North East Atlantic. Low angle close-up of Katy panning to a close-up of James’ face, both of them focused on the laptop screen in front of them. Close-up of the computer screen in front of them, John’s hand pointing to one of the onscreen infographics. Low angle view of part of a platform topside and the tower crane alongside, seen against a pale blue sky. Mid-view footage of workers dressed in hardhats and safety gear aboard a platform, blue seas and skies visible in the background. Since then, legislation and technology have changed, and offshore facilities installed in the north-east Atlantic after 9 February 1999 must now be designed to be completely removed. Gravity Base Structure (GBS) The Topsides is supported by a massive concete pedestal called the Gravity Base Structure (GBS) which was constructed in Bull Arm, Newfoundland and Labrador. Four cells are elongated to shafts supporting the platform deck. Once the visible part has degraded, the subsea section of the legs is expected to last for another 300-500 years. The legs (which each weigh around 6,000 tonnes) would need to be lifted and secured to preserve their integrity during transportation to shore by heavy lift vessel for dismantling and recycling. Independent studies suggest that successfully refloating the GBS would prove extremely difficult. Rear view close-up of John and the base structure imagery on the screen he is pointing to. Below is an overview of the four major crude oil classifications: Light crude oil; Any crude oil with API gravity of over 31.1 degrees falls into the light crude oil category. We would apply for a continuation of the existing safety zone around the gravity base structures. After cutting, the legs would need to be transported to shore for recycling. Gravity Base Tank The construction yard at Hunterston was used for the final time between 1993 and 1996 when a Gravity Base Tank was built shortly after the Submarine Dry Dock was … Further, these substructures provide the advantageous option of using the gravity base for oil storage. The rest of the structures would be left in situ on the seabed. Once the public consultation period has ended, and the Department for Business, Energy and Industrial Strategy (BEIS) is satisfied that there are sufficient grounds to recommend that this infrastructure be left in place, BEIS will initiate consultations with other signatories to the OSPAR Convention to seek their approval to leave this infrastructure in place. Mid-view footage of Katy Lin as she speaks, seen against the slightly out of focus background of an office environment. A gravity base offshore production platform structure and, more particularly, a production platform for use in an arctic environment, including an encircling structure having a predetermined configuration the protection of the offshore structure in iceberg-infested waters which are capable of resisting the destructive forces of an impact produced by a large iceberg. Oil & Gas; Miscellaneous; F3-FB Production Platform SF; Projects. The concrete gravity oil storage base concept was selected due to the insufficient capacity of the Danish oil line to Fredericia. This would involve capping the legs with concrete and installing navigation aids. More footage of Katy and James in profile, both focused on a document in front of them on the table. The Millom West platform in UK Block 113/26a in the Morecambe area of the Irish Sea was installed earlier this year, but it wasn't without significant change in the base of the production structure at nearly the last moment. The GBS are made of thick concrete reinforced with steel bars and are ballasted down during installation, anchoring them securely to the seabed. As with option 1, the location of each structure will be marked on all charts documented in the FishSAFE database, and protected by a safety zone. Read our sustainability and environmental reports. There are 64 storage cells in the three concrete bases, 42 of which were used to store oil. #malaysia #marine #offshore #oilandgas #design #drafting #construction #fabrication #lklmarine The platform consists of two parts the jacket and the deck. The concept can serve almost any offshore … The resulting base oil is clear and colorless but also has a VI above 120. NEXT. After the topside (platform portion of the structure) has been removed, the upper part of the legs of the gravity base structures would be cut at a point 55m below sea level, in line with International Maritime Organisation (IMO) guidance. Chief Executive, Scottish Fishermen’s Federation, Bertie Armstrong / Chief Executive, Scottish Fishermen’s Federation. …and a method of altering the buoyancy would need to be found for its journey to the surface. The other end of the cylinder descends around 700 feet (213 meters) into the ocean depths. A close-up cutting to a high angle view of a jet of water pounding the concrete alongside the drill bit cutting into the block of concrete. Description This report provides an overview of the decommissioning options available to Offshore Concrete Gravity Based Structures (CGBS).It is a minor update of report 484 (1) … It is technically extremely high risk of failure, and also a very high safety risk, far higher than we would accept in any other part of our operations. F3-FB Production Platform SF. The unique South Arne platform sits on a concrete tank which is used to store oil. evaluating the safety risk to other users of the sea if the structures are left in place. We are able to offer a wide range of services within the areas Offshore Oil … Slightly out of focus front view footage of Katy and James looking over documents on the table in front of them, cutting to a high angle view of the documents on the table under Katy’s hands, James’ face again partially visible in profile at frame-right. High angle view of four concrete legs, rough waters swirling around them. Roger Esson / Chief Executive, Decom North Sea. Footage of a vessel rising and dipping in rough seas, the Brent platforms visible in the distance. Bird’s eye view of workers dressed in safety gear working to attach ropes to one of the many containers aboard the platform. Learn More . A floating storage system was largely ruled out by the relatively shallow water depth of 60m and the problems this would present with the risers and anchoring systems. After using the comparative assessment process to assess the decommissioning options in terms of the five criteria of: technical feasibility, effects on society, environmental impact, risk to safety, and cost, Shell’s recommendation is to leave the GBS in place. Here's how it was constructed. In order to test a method for cutting through the reinforced concrete legs, onshore cutting trials have been conducted. Three of the Brent platforms are supported by reinforced concrete gravity base structures. GBS were designed to overcome the challenges of producing oil and gas in the North Sea during the 1970s. As a general principle, the fishing view is, if it’s going to be there and going to cause an obstruction, then let’s be able to see it. High angle view of the ocean and towing vessels below, as from the point of view of the tops of the legs, the storage cells of the base structure also visible below. Computer generated imagery depicting a panning wide view of one of the Brent platforms seen against the background of grey skies above and grey swirling waters below. Wide footage of James and other colleagues seated either side of a long table in a conference room, their attention on the screen against the wall beyond on which an infographic is projected. The light blue shading in the upper frame depicts the sky, and is separated from the dark blue shading of the underwater environment in the lower frame by a white line. The cost of this partial removal would be very high, which is something Shell is required to consider. The production platform Hibernia is the world's largest oil platform (by weight) and consists of a 37,000 t (41,000 short tons) integrated topsides facility mounted on a 600,000 t (660,000 short … The structure was installed by the Joint Venture Group, consisting of Consafe Engineering, Genesis Oil … All of these structures were partially built in a drydock and then completed afloat in sheltered waters. This report provides an overview of the decommissioning options available to Offshore Concrete Gravity Based Structures (CGBS). The GBS, which sits on the ocean floor, is 111 meters high and has storage capacity for 1.3 million barrels of crude oil … Attempting to lift the structures from the seabed could also collapse them. The continuing computer generated imagery shows the yellow lines dissipating, but the structure continues to rise. The Brent Field’s equal partners are Shell UK Ltd and Esso Exploration and Production UK Ltd. Fig. The UK is a signatory to the OSPAR Convention. A large number of platforms were constructed of this type, characterized by the Olav Olsen's "Condeep" concept. How to Decommission Brent: Gravity Base Structures, Title:  How_to_Decommission_CUT_DOWN_1_Gravity_Based_Str_FINAL_MASTER-_211216_. Shell can now claim a 70% reimbursement on the cost of decommissioning, from the taxes it previously paid. In addition, it is more resistant to oxidation than Group I oils. The caisson is surrounded by an ice wall, which consists of 16 concrete teeth. GRAVITY PLATFORM GBS: gravity based structure-concrete, steel Condeep (concrete deep water structure) :gravity base structure for oil platforms developed and … 石油プラットフォーム(せきゆプラットフォーム、oil platform)または石油リグ(せきゆリグ、oil rig)は、海底から石油や天然ガスを掘削・生産するために必要な労働者や機械類を収容する、海上に設置される規模の大きい海洋構造物である。水深など環境に応じて、プラットフォームを海底につないで人工島にするか、あるいは浮かせた状態にする。, 一般的に、石油プラットフォームは大陸棚に設置されるが、技術の進歩に伴ってより深海での掘削・石油生産が可能になっている。原油価格の動向によって、掘削コストの合理性は変動する。指向性の掘削技術(Directional drilling)により、1つのプラットフォームから異なる深度の複数の場所(約8km以内)に向けて、30ほどの坑井の掘削を行うことが可能である。 In addition to resisting icebergs and other environmental loads, the … Hebron is an offshore oil field estimated to contain more than 700 million barrels of recoverable resources. Platform with a total heiõht of 380 m, a deadweight of 750000 t, and a crude oil storage capacity of 2 million barrels (320000 m D) (Fig. The challenges and solutions for decommissioning of the gravity base structures of three of the Brent platforms. 2) is designed to support the topsides structure and will rest on the ocean floor, held in place by gravity. This story of how British Steel built a Ore and Coal deep sea port at Hunterston. High angle footage of James and colleagues seated either side of the long conference table, this time the windows and white walls behind James forming the background. The story of the Gravity Steel Base of the Maureen Alpha Oilrig that was built here and subsequently went to produce oil in the North sea before being decommissioned in 2001. Katy Lin / Decommissioning Project Engineer. CONCRETE gravity base Description Offshore oil development, especially in the North Sea, has brought up a completely different design of fixed platform: concrete platforms. ­Spar platform: Finally, if you absolutely need to drill a hole at a depth of 10,000 feet (3,048 meters), then the spar platform is the oil rig for you. The structures would be marked on maritime charts and in FishSafe, the fishermen’s GPS warning system. There are five main types of fixed platform, ranging from the conventional fixed platform used at depths of up to 150m, to the tension leg platform that can be used at depths of 2000m. Legs up, is the choice of the fisherman. Low angle view of the helicopter landing on the topside against the background of a cloudy blue sky. Close-up of Roger Esson as he speaks, seen against an out of focus background of an office environment. An oil platform, offshore platform, or offshore drilling rig is a large structure with facilities for well drilling to explore, extract, store, and process petroleum and natural gas that lies in rock formations beneath the seabed. Shell has investigated completely removing the structures from the sea. At that time the North Sea pipeline network was still in its infancy, so oil had to be stored temporarily in cells on the seabed then pumped into tankers for transport to market. …and also dialogue with our Independent Review Group, we’ve come to the conclusion that we won’t carry that option forward. In the first test, only diamond wire was used. / 46.7504361; -48.7829278 Coordinates: 46°45′1.57″N … A gravity base structure for an offshore platform includes a caisson having a bottom slab, a top slab, and inner and outer concentric walls which extend between the bottom and top … This was something that I have been warning about for … Each upper section has a diameter of almost 20 metres and weighs more than 5,000 tonnes. Removing the upper portion of the legs to a depth 55 metres below sea level would be required to comply with the International Maritime Organisation (IMO) recommendation on the partial removal of structures. The field was first discovered in 1980, and is located offshore Newfoundland and Labrador (NL) in the Jeanne d'Arc Basin. At that time, there was no pipeline infrastructure, and the capacity of heavy lift vessels was only … Gravity Based Structures (GBS) are regularly applied in the oil and gas industry and in the wind farm industry and can be attractive solutions with respect to installation method and time. Bird’s eye view of the platform and the vessels below, seen against the background of the ocean and some land. The oil rig itself appears to have been modeled after a real-life offshore “Jack-Up” oil … New Hebron offshore oil platform a Canadian engineering marvel March 12, 2018 6.15pm EDT. Close-up of Roger Esson as he speaks, seen against an out of focus background of an office environment. Instrumental music with synthesised effects, at times with softer tones – some delicate, some eerie and suspenseful – and at other times building to a stronger rhythm. At the time of their construction, decommissioning was not at the forefront of people’s minds and was not a prominent design consideration. The platform has a production capacity of 150,000 barrels per day with total recoverable oil reserves estimated to be 615 million barrels. MonobaseWind Gravity base Concept and Marine Design. To refloat the Gravity Base Structures, this installation would need to be reversed: Again, the outline graphic appears in place of the previous imagery. … It is a minor update of report 484 (1) published in 2012. The option to leave the gravity base structure in place, really mirrors what’s already happened in the Norwegian sector where the structures have been left in place with navigation aids on there, to aid shipping and fishing. The continuing computer generated imagery highlights the concrete caps of the legs in yellow and the navigation aid in red, as they are respectively mentioned by the narrator. The Arkutun Dagi field of the Sakhalin 1 Project is an oil and gas field located off the east coast of Sakhalin Island in the Russian Federation. The early development of gravity platforms in the 1970s was driven by the generic requirement to store large volumes of oil and support a heavy topsides in deepwater. Bird’s eye view of one of the Brent platforms surrounded by blue ocean waters. Aerial view of one of the platform topsides and the dark blue seas below, pulling back to a wider view of the same. The Troll A gas platform is not only the deepest gravity-based structure in the world, but the tallest structure ever moved – measuring 472m in height. In the Draft Brent Decommissioning Programme, and after extensive analysis and consultation, Shell proposes to leave some of the existing infrastructure in place – this consists of the concrete gravity based structures and the storage cells on Brent Bravo, Charlie and Delta, in addition to the footings of the Steel Jacket on Brent Alpha. Down Time Analysis Offshore wind logistics . Gravity Base Tank The Harding Oil Platform has been active for many years now. More information about the OSPAR Convention, and the institution that was created to implement the OSPAR Convention (the OSPAR Commission) can be found here: This approach is not without precedent. The base would need to be excavated and hydraulics used to prize it from the sea-floor…. It is a gravity base structure, built in the … Shell Pecten centred on a white background with text displaying below. Filmed by Dragonflight Drones The unique South Arne platform sits on a concrete tank which is used to store oil. It’s made up of some cells for storage and legs. Wide view of the platform’s concrete legs rising from the ocean. We are able to offer a wide range of services within the areas Offshore Oil and Gas, Offshore Wind, Naval Architecture, Marine Operations, Platform Removals and Salvage. Compression Modules ; Jackets; Living Quarters; Platforms; Process Modules; Subsea Manifolds; Miscellaneous; Offshore Renewables; Print pagina. 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