Monday, August 21, 2017
Prelude FLNG

The first part of this article in the February issue of Sea Breezes considered key trends in the evolution of oceangoing LNG ships from the first commercial cargo, in 1964, to the present day, noting in particular the growth in cargo capacity from 27,400m3 in the case of the Methane Princess to today’s standard of about 175,000m3. In recent years, the LNG industry has faced several significant technical challenges related to the floating production and re-gasifi cation of LNG, and the exploitation of gas reserves in Arctic regions.

Arctic LNG
During the 1970s much work was expended into assessing the feasibility of producing and exporting natural gas from the hydrocarbon-rich islands and offshore regions in the Canadian and Alaskan Arctic. One consideration for transporting the gas was to use submarines which, naturally, would be unaffected by surface ice and weather conditions. Moreover, prevailing water depths of over 350 metres would enable submarines to maintain cruising depth and speed over practically the entire length of the proposed routes. For this purpose, General Dynamics developed a series of designs of Arctic LNG submarines of 27~140,000m3. As well as nuclear propulsion, these designs featured a traditional steam-powered system using cargo boil-off gas (BOG) and, when submerged, re-circulated exhaust gas mixed with oxygen from a liquid oxygen tank. The idea of using submarines also came to the fore in studies of transporting natural gas in compressed form, but neither LNG nor CNG prototypes were ever built.

As an alternative to submarines, the Arctic Pilot Project conceived in 1976 by Petro-Canada and partners envisioned the use of two 140,000m3 ice-breaking LNG carriers each making about 15 round trips per year from a shipping terminal on the south coast of Melville Island located on the eastern side of Sabine Peninsula. The routing would take the ships in an easterly direction via Parry Channel, then across Baffin Bay and through Davies Strait to a receiving facility in St. John, New Brunswick. Dubbed the “Melville Island Monsters”, the ships were to be 372m long by 43m wide, and 11m draft, with three propeller shafts providing for 18.5 knots performance in open sea and a constant 3 knots through 2.1m thick first-year ice. Propulsion was to be electric, with six generators driven by six gas turbines, three capable of burning BOG and heavy fuel oil; the other trio just BOG.

Whilst the Arctic Pilot Project failed to make headway, the plans for the Melville Island monsters have, forty years later, many similarities to the ships being built for the Yamal LNG project in Siberia. In 2013, Daewoo Shipbuilding & Marine Engineering was chosen as the winning bidder to build fifteen 172,000m3 Arc-7 ice-class LNG ships for the project. With an enforced steel hull twenty-five percent thicker than equally-sized non ice-class ships, the Arc-7s are designed to pass continuously through ice up to 2.1 metres thick, and without the assistance of Russia’s nuclear icebreakers. The Russian Register Arc-7 standard is equivalent to an intermediate level between Polar Class 3 and Polar Class 4 of the international association of classification societies. The ships will be highly winterized enabling normal operation in -45 Celsius ambient temperature, with the equipment certified for work at -52 Celsius.

Starting at plateau output in 2020, and during each of the subsequent 25 years at least, the Yamal project will export 16.5 million tonnes of LNG. Shipments will be in a westbound direction from Sabetta port during winter and spring, and eastward in the other seasons when ice flows retreat sufficiently in the Northern Sea Route to enable Far Eastern markets to be served. Yamal’s main sponsor is Novatek with partners Total, and China National Petroleum Corporation; the Chinese being the key financiers. The first ship was launched in January 2016 and is due for delivery to Russian owner Sovcomflot in February 2017. It was to be named simply as SCF Yamal, but was eventually christened Christophe de Margerie in memory of the late President of Total who pushed the project forward despite western disapproval of the company’s backing of a major energy export project in Russia. On 20th October 2014, less than ten months after the final investment decision on the project, de Margerie was killed when his private jet collided with a snow plough when taking off from Moscow airport.

The Arc-7s are double-acting - designed to steam ahead in open water and thin ice, but turn around and proceed astern in heavy ice conditions. A key feature of the ships’ manoeuvrability in Yamal’s ice conditions are three 15 MW azimuth propulsion units – or azipods as manufacturers ABB has dubbed them – each consisting of a steerable pod containing an electric motor drive. The trio of pods will be powered by six Wartsila duel-fuel engines capable of handling the wide load variations that can occur when a ship passes through thick ice.

FLNG
Another technologically challenge witnessed by the LNG industry lately has been the development of floating production & liquefaction units – known as FLNGs – as sponsors seek to exploit small or remote offshore gas reserves for which traditional land-based facilities are unsuited. Floating liquefaction is not a new concept. In fact, it predates the first ships. Prior to the converted Methane Pioneer (a 1945-built Liberty ship) that delivered 7 cargoes from the US Gulf to Canvey Island, and before the first commercial cargo from Algeria to the UK, Chicago Stock Yards’ original concept in the 1950s was FLNG. The barge, tethered to shore, was a relatively simple design as compared to the sophisticated vessels presently being planned where the civil and chemical engineering of the topsides account for a much greater share of the challenges, and costs, than the hull.

It’s doubtful those pioneering fellows at Chicago Stock Yards could have envisioned the scope of Shell’s Prelude FLNG – the first to be ordered in the modern era – which, at 488m (1,600 feet) long, 74m (240 feet) wide and 44m (143 feet) deep from the keel to the main deck will, along with its contents, weigh around 600,000 tonnes. By comparison, the oil tanker Seawise Giant (1979~2009), generally considered the largest ship ever built, had a loaded displacement of 657,019 tonnes. Shell refers to Prelude FLNG, which will operate in waters of 200~250 metres’ depth, as a floating facility rather than a ship, and, as such, it will be the world’s largest ever built when eventually completed, in early 2018 perhaps, which would be almost three years behind the original schedule.

The behemoth, designed for 50 years’ service at various locations, will be towed to the Prelude gas field, some 475 kilometres north-east of Broome, Western Australia, and moored there for 20~25 years before needing to dock for inspection and overhaul. Each of three Rolls-Royce azimuth 5.2MW thrusters for local manoeuvring are situated at the base of a trunk that links to a higher maintenance workshop area with cranage. The Prelude FLNG facility is being built by Samsung Heavy Industries to TGZ membrane design and will produce annually 5.3 million tonnes of petroleum liquids – including 3.6 million tonnes of LNG.

The delays with Prelude have meant that it will not be the first offshore FLNG unit to be built; that feat was achieved by Petronas’ PFLNG Satu, ordered after the Shell contract, and delivered by Daewoo in May 2016. Of GT membrane design, the PFLNG Satu has been deployed at the Kanowit gas field off Sarawak where it will produce 1.2 million tonnes LNG per annum.

Unfortunately, the advent of FLNG has coincided with deep and protracted declines in oil and gas prices, making new project development less economic. Shell has cancelled options it had at Samsung to order three more of the giant units that would have been used to exploit other offshore gas fields. Petronas has postponed delivery of its second unit - the PFLG Dua - which had its keel-laying ceremony at Daewoo in April 2016 and is now expected not to be commissioned until 2020 – two years later than originally planned. More positively, Italians ENI and partners BP seem about ready to order an FLNG unit at Daewoo to develop a project at Coral South off Mozambique with 3.3 million tonnes per year of LNG.

Owners of older conventional LNG ships; of which a dozen or more have changed hands over the past couple of years, have been studying the prospects of converting them to FLNG units. Golar LNG – which has already converted the 1970s built Golar Spirit and Golar Freeze to floating storage & regasification units, or FSRUs described in the next section, is involved in projects that would entail converting ships of similar vintage to FLNG units.

Read the rest of this article with additional pictures in Sea Breezes Magazine - March 2017 Issue
Click here to subscribe

Subscribe Graphic

Latest Issue - Look Inside!

Hong Kong Express

Most Popular

  • 1
  • 2

Latest Products

Maritime Log

  • Replacement Cranes Giving Humber a Lift +

    Gottwald Cranes Unloading Two new Gottwald 820 cranes were delivered in June to the Humber International Terminal of Associated British Ports (ABP) at Read More
  • Unified Ship Design Rolls Off the Drawing Board +

    Unified Ship Design The UK-based engineering company Rolls-Royce has radically overhauled its vessel design philosophy in a bid to optimise construction and operations Read More
  • World's Largest in Felixstowe +

    OOCL Hong Kong The world’s largest container ship, the OOCL Hong Kong, of 210,890gt and 21,413teu, made her maiden call at Felixstowe on Read More
  • Southampton's Record in a Weekend +

    Southampton Port Southampton welcomed 15 cruise ships in three days making it the busiest cruise weekend on record. Read More
  • Cleaning up Plastic from the Oceans +

    Cleaning up Plastic from the Oceans The marine geophysical company Petroleum Geo-Services (PG-S), of Oslo, has developed a concept for the largescale collection of plastic in Read More
  • 1
  • 2
  • 3

North America

  • Battleship Texas "Sinks" +

    USS Texas Having survived two world wars and now a museum ship, New York-class battleship USS Texas (BB-35), began to sink at Read More
  • Third Ice Class Ocean Tug for Foss +

    Nicole Foss On 6 June Foss Maritime christened their third Arctic-class ocean tug, Nicole Foss, at the Foss Waterway Seaport in Tacoma, Read More
  • "You may fire when ready, Gridley" +

    McCulloch On 1 May 1898, when US Admiral George Dewey gave this order to the Captain of his 344-foot Flagship, USS Read More
  • ‘Perfect Storm’ Star’s New Role +

    Tamora Decommissioned 74 year-old, US Coast Guard cutter, Tamaroa, famous for her role in the book The Perfect Storm and the Read More
  • Another Sign Summer’s Almost Here +

    MS Mount Washington Classed by the American Bureau of Shipping, MS Mount Washington, the 129-year-old, 220- foot flagship of the Winnipesaukee Flagship Corporation Read More
  • 1
  • 2
  • 3

Asia-Pacific

  • Trans-Shipment Hub for Coal Cargo +

    Coal Hub A coal imports trans-shipment hub centred on a floating platform is being established in Vietnamese waters by three partners. Read More
  • Court Stops Demolition Over Radioactive Claim +

    North Sea Producer The breaking up of the former floating oil production and storage tanker (FPSO) North Sea Producer was halted by the Read More
  • Two Crewmen Died Of 'Foul Play At The Hands Of Others' +

    Sage Sagittarius The inquest into the deaths of two crew members of the bulk carrier Sage Sagittarius, 73,427dwt, when the ship was Read More
  • Seven Die in Destroyer Collision +

    USS Fitzgerald Seven sailors died when the US, Navy destroyer Fitzgerald was in a collision with the Philippine-flag container ship ACX Crystal, Read More
  • Alert Over Gas Cylinder Safety Checks +

    Emerald Princess A gas cylinder that had just passed a mandatory detailed safety inspection exploded while being refilled and killed a member Read More
  • 1
  • 2
  • 3

Naval Focus

  • Los Angeles Class Decommissioning +

    USS Dallas American News The end of May saw a lot of submarine news within the US Navy with the decommissioning of Read More
  • HMS Westminster Returns to Service +

    HMS Westminster British News After two years out of service undergoing a major reconstruction and refit, the Type 23 frigate HMS Westminster Read More
  • USS Tripoli Launched Ahead of Schedule +

    USS Tripoli American News Ingalls Shipbuilding achieved a remarkable achievement when they launched the latest America class amphibious assault ship, USS Tripoli, Read More
  • New Voyages for USS Enterprise +

    USS Enterprise American News Huntington Ingalls Industries was awarded a $25.5 million contract to essentially start the advanced fabrication of the third Read More
  • Naval Update - April 2017 +

    USS Antietam American News On Tuesday 31 January, the Ticonderoga class cruiser USS Antietam ran aground off the coast of Yokosuka in Read More
  • 1
  • 2
  • 3

Ferry World

  • Woods Hole, Martha’s Vineyard and Nantucket Steamship Authority +

    Iyanough The Isle of Wight has always been associated in my mind with the “Southampton, Isle of Wight and South of Read More
  • CalMac's Isle of Lewis +

    Isle of Lewis This fine study of the Isle of Lewis in the dramatic environs of Castlebay, Barra, is a reminder she has Read More
  • Rotor Sails +

    Viking Grace If you thought the ungainly looking rotor sail system, an invention from the early 20th Century, was gone forever, you Read More
  • New Fast Ferry Deliveries +

    Express 3 News of Fast ferry investment; Express 3 has sailed from Tasmania on her delivery voyage to Denmark via the Panama Read More
  • Ferry Implications of Brexit +

    Cote des Dunes It must be a uniquely worrying time for operators of UK Ro-Ro Ferry ports with an uncertain future entirely out Read More
  • 1
  • 2
  • 3

Sail Review/Coastal Comment

  • Oil Downturn Continues +

    Ocean Seeker The offshore oil downturn has been taking its toll around the North Sea amongst many rig boat operators and also Read More
  • Rendez-Vous 2017 Tall Ships Regatta +

    Artemis On April 6 Dutch sailing vessels took part in the Race of the Classics from Holland across the North Sea Read More
  • Pioneering Spirit For Teeside +

    Pioneering Spirit Teesside has lost most of its steel manufacturing and much of the shipping traffic it brought, but at the other Read More
  • Troubles for Ahlmarks' Skagern +

    Skagern Ahlmark is Sweden’s oldest shipping company, founded by 1847, and still going strong, if not as strong as they used Read More
  • The Dawn +

    Dawn The 81ft Dawn, a ‘heritage’ sailing barge with an open hold and tiller-steered, took out trips last summer for people Read More
  • 1
  • 2
  • 3

From the Lookout

  • Captain Fryatt, The Martyr Of Bruges +

    SS Brussels and Captain Charles Fryatt At the end of the Great War, the bodies of only three heroes were ever brought back to England and Read More
  • Brahminy Kites in Port Sweetenham +

    Brahminy Kite Recently, I have been back in touch with Captain John Anderson; he now lives in Canada, but we sailed together Read More
  • Peel Ports Appoints New Port Director +

    Jouke Schaap Never a dull moment at Peel Ports which owns and operates six of the UK's major ports – Liverpool, Heysham, Manchester Read More
  • Exhibition on HQS Wellington +

    HQS Wellington News of a really interesting free exhibition on board HQS Wellington entitled "Abandon Ship! – Surviving the Wartime Atlantic". Read More
  • MOL Triumph +

    MOL Triumph Gary Davies of Maritime Photographic sent me this "jaw dropping" photograph of the MOL Triumph which dramatically conveys the sheer Read More
  • 1
  • 2
  • 3

Cruise News/Superyacht News

  • Gliding up the Thames +

    Glider SS18 It's been eight years in the making but finally the first Glider was unveiled in London last month. Read More
  • Yacht With a Pinch of Porsche +

    Dynamiq GTT 115 Taking the spirit of highperformance sports car styling to the high seas, the Dynamiq GTT 115 is designed to appeal Read More
  • The “Celebrity Edge” +

    Celebrity Edge You have to admire the innovative mindset that is evident within the creative corridors of a modern cruise line. Read More
  • The Mailship vs The Corsair +

    Windsor Castle and Corsair Before the Internet, Websites, Blogs and eNewsletters presented themselves to an unsuspecting world, the arrival of the monthly passenger shipping Read More
  • Cloud 9 Launched in Italy +

    Cloud 9 Nine different colours of cloudlike smoke were used as a backdrop when Cloud 9, the brand new 74 metre superyacht Read More
  • 1
  • 2
  • 3

Ships, Ports and Places

TSS Awatea

Secrets of the "Awatea"

Somewhere off the North African port of Béjaïa, deep on the floor of the Mediterranean Sea, lie the remains of Read More
Dalia

A Different Type of Railway Steamer

When one thinks of Railway steamers of the past, the mind is invariably drawn to smart cross-channel or short-sea packets. Read More
  • 1
  • 2

Companies, Events and Other Features

Painting of Venus

A Quartet for the North Sea

The chain of events that led to the Bergen Line building the Venus started in the head office of Swedish Read More
MS Pacheco

Happy Seagoing Days - MacAndrew Line

After gaining my Masters Certificate in July 1962, I started to look for another job on General cargo ships, but Read More
  • 1
  • 2