Technology

Steel and coral off Mozambique

 By Marilia Cioni

Why the first cut of a steel sheet in South Korea is so important for Mozambique and Eni…

Even in the shipyards everything stops, albeit briefly, to observe ancient customs and their complex rituals. Everyone knows about the launching of a ship and the breaking of a champagne bottle over the bow. Less well-known is the first steel cut: a little like the laying of the first stone in a building project, the cutting of the first steel sheet for the hull is the first tangible step in the building of a ship. It has been commemorated for centuries, from back when ships were made of wood and less sophisticated machinery was used to cut them. Today’s equipment is more advanced, and the ceremony now involves pressing a button to operate a plasma cutter that slices through a steel sheet. Cutting edge technology, but the symbolism is the same: it marks the moment, after the engineering work is complete and the necessary materials acquired, when the project becomes a reality; the design, until now just a concept in the engineers’ minds, and on their computers, comes together with the raw material that will make it real, ready to set sail, steer a course and begin production.

The Coral Sul FLNG

A few days ago, on 6 September to be precise, in Geoje, South Korea, Samsung Heavy Industries’ shipyard saw the first steel cut of the hull of the Coral Sul Floating Liquefied Natural Gas (FLNG) offshore vessel. The Samsung Heavy Industries’ shipyard is one of the world’s major construction yards for ships and offshore facilities, and the Coral Sul FLNG will enable production and monetisation to begin of the huge gas deposits discovered by Eni off the coast of Mozambique. The deposits total about 85 Tcf of gas, volumes that will enable the country to become one of the world’s main gas producers. The Coral Sul FLNG will contain a treatment and liquefaction plant to transform the extracted gas into Liquefied Natural Gas (LNG), large storage tanks and an advanced system for offloading it onto ships for transportation worldwide to its final destination. All this technology, and the personnel that will put it to use, will ensure Mozambique is a global gas producer by 2022.

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The floating gas liquefaction unit (FLNG) named "Coral Sul"

The decision to use an FLNG vessel to develop the Coral field was based on their properties and location: “This technology is suitable if transporting the gas by land is problematic because of the distance from the coast or the nature of the sea bed,” explains Stefano Rovelli, Project Director of the Coral Sul development. “At the same time, it requires deposits that will ensure a continuous supply for 25-30 years, as the Coral deposits will.”

The first in the world

This is young technology: there is currently one FLNG operating in Malaysia (producing 1.2 Mtpa of LNG), with another soon becoming operational in Australia (producing 3.6 Mtpa of LNG). The Coral Sul FLNG (with an annual liquefaction capacity of 3.4 million metric tons of LNG) will be the first of its kind in Africa and the world’s first in ultra-deepwater. “The challenge,” continues Rovelli, “is to use the known technologies of separation, treatment, liquefaction and storage of gas, compressing it sufficiently for the limited space on-board ship. On land, such storage modules require square kilometres of space, but on-board ship they must be stacked to reduce the space required to a tenth. The equipment must also function safely in extreme weather conditions, as the Coral Sul will be operating in a region prone to cyclones. The entire design employs the highest safety standards for on-board personnel and minimises any possible environmental impact.”

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Map of the Coral South Project, the first development of the considerable gas resources discovered by Eni in Area 4

To construct the vessel, Eni has bought together the expertise of several companies, ensuring it has the best in the industry: the TJS consortium (France’s TechnipFMC, Japan’s JGC and South Korea’s Samsung Heavy Industries) will be responsible for the hull, gas production equipment, risers and flowlines; the UK’s BHGE for the subsea production systems; Norway’s Aker for the umbilicals; and Italy’s Saipem for the wells. “With personnel in Houston, Paris, Yokohama, Geoje, Singapore, Bristol, Fornebu (Norway) and Mozambique,” says Rovelli, “organising our work and meetings isn’t easy across so many time zones. But it has enabled us to bring together the industry’s top experts. Professionals that have worked on other FLNGs, who bring with them the lessons learned from other projects and that guarantee our success.”

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6 full-flexible flowlines and risers connecting 3 cluster manifolds to the FLNG.

Alongside each of them, and in all these countries, it is Eni’s engineers who hold the reins. “The particular feature of this vessel is the storing of the LNG produced by the process system at -162° C,” explains Luca Faccenda, FLNG Hull & Living Quarter Project Execution Manager, who, in Korea, is overseeing the hull’s engineering and construction. “Such extreme cryogenic conditions require special membrane storage systems, and a different hull from a normal Floating Production Storage and Offloading (FPSO) vessel where oil is stored at atmospheric pressure and ambient temperature. Storage on the Coral Sul FLNG will be at atmospheric pressure but well below 0° C. Its shape and size are also different: the hull is over 400 m long and its construction involves the assembly of hundreds of steel blocks, weighing over 140 thousand metric tons in all. Another particular feature of the Coral Sul FLNG is its extensive living quarters, accommodating about 350 personnel at the busiest times during offshore tests, and during plant maintenance.”

On-the-job training

As well as developing leading edge technology, the shipyard also provides excellent learning opportunities for a country that is a newcomer to the gas industry. To maximise skills acquisition in Mozambique, Eni and its partners in Area 4 have involved young Mozambican engineers right from the project’s early stages. The aim is to give them a profound understanding of the vessel’s characteristics and thus an active role once it is operational. After initial on-the-job training, the Mozambican engineers will be on hand in Geoje to follow the vessel’s construction. The first is already there, Liudmil Portugal, who expressed the pride and excitement of everyone at the first steel cut: “This project is very important for each of us and for Mozambique. For me, it’s a great opportunity for professional growth and to contribute to the growth of my country.”
The project’s next key stage, in Geoje in November, will be to begin manufacturing the process modules.
And this is just the start of a long journey…

READ ALSO: The jewel of the Indian ocean by Marilia Cioni

about the author
Marilia Cioni
Marilia is a content producer and press officer at Eni, where she focuses on Exploration, Upstream and Technical Activities in Sub-Saharan Africa. Previously she worked for Italian news agency Agi, where she was in charge of international relations.