First floating liquefied natural gas project

Paul Boughton

From the world’s first floating liquefied natural gas (FLNG) project, to improved Brazilian output and successful Indonesian pilots, there is major investment in new production technology around the world. Eugene McCarthy reports.

In what the company describes as an important step, Shell has laid the keel for Prelude FLNG, the world’s first floating liquefied natural gas (FLNG) project.

When complete, Prelude is expected to be the largest offshore floating facility ever built. The hull will now be assembled in the dry dock, before the turret and the topsides are fitted at Samsung Heavy Industries’ Geoje shipyard in South Korea.

“This is a key milestone in Prelude’s story,” said Rob Kretzers, Shell executive vice president projects. “Innovative thinking and leading edge technology, as well as hard work from those at Shell and our partners, have helped us reach this significant point in construction. Prelude’s size and scale is unprecedented and I look forward to seeing this enormous structure take shape. Shell is pioneering FLNG which has the potential to revolutionise the way natural gas resources are developed."

FLNG will allow Shell to produce natural gas at sea, turn it into liquefied natural gas and then transfer it directly to the ships that will transport it to customers. It will open up new opportunities for countries looking to develop their gas resources and bring more natural gas to market.

Large steel sections known as blocks that will form the hull are being manufactured in the Geoje shipyard, with more than 1600 already complete. One section can be the size of a large house. The 93-metre high turret mooring system is under construction in Dubai and will be transported to Geoje in five parts. The turret will run vertically through one end of the facility and will be anchored to the seabed by four groups of mooring lines. It will allow the facility to rotate with the direction of the wind.

Once complete, the 600,000 tonnes facility will be almost half a kilometre in length (Fig. 1). It will be moored and hooked up to the undersea infrastructure, around 475 km north-east of Broome, Western Australia.

Despite its huge dimensions, the facility is only one-quarter the size of an equivalent plant on land. Shell’s technology has been adapted for floating LNG, and engineers designed components that will stack vertically to save space. The cooling plant, for example, will be placed above the vast storage tanks that have a capacity equivalent to around 175 Olympic swimming pools. Specially designed risers will draw 50 million litres of cold water from the ocean every hour to help cool the natural gas.

Brazilian production on the up

Carlos Tadeu Fraga, executive manager for Petrobras’ pre-salt exploration and production, told the recent Offshore Technology Conference (OTC 2013) that between 2008 and April 2013 the cumulative production from the pre-salt reservoirs in the Campos and Santos Basins has reached 192.4 million barrels of oil equivalent (boe – both oil and gas).

According to Fraga, daily production exceeded 311,000bbl/d on 17 April, more than double the daily average production of 121,000 barrels in 2011. The average pre-salt production in April was 294,000 bbl/d.

He also revealed that there are seven platforms and 19 wells currently producing in the pre-salt of both basins. He highlighted that the average production for each well of FPSO Cidade de Angra dos Reis, in the Lula pilot project, is approximately 25,000bbl/d, higher than the original estimates of 15,000bbl/d. He also said that FPSO Cidade de São Paulo, in Sapinhoá, will start production in January and FPSO Cidade de Paraty, allocated to Lula Nordeste, is already in place and will start production in June.

Petrobras’ business plan for 2013-2017 forecasts that the milestone of 1 million bbl/d operated by itself in the pre-salt will be exceeded in 2017, reaching 2.1 million bbl/d in 2020. The pre-salt was discovered in 2006 with the field currently known as Lula (formerly known as Tupi), in the Santos Basin, off the coast of Rio de Janeiro. The first pre-salt oil was produced in September 2008 in the Jubarte field, in the Campos Basin, when a well was connected to the P-34 platform which was already operating in post-salt reservoirs of the basin.

Success in Sumatra

NuEnergy Gas says that pilot production operations have recommenced at the Muara Enim pilot production site in South Sumatra, Indonesia. With completions across five coal seams via the use of radial jet technology, NuEnergy expected gas and water production to exceed past results. This expectation has been met with gas production recommencing at higher rates within two hours of the commencement of dewatering operations.

NuEnergy’s chairman Graeme Robertson commented: “We are pleased to have successfully recommenced pilot production at Muara Enim, representing another important step towards achieving our first gas sale, expected in December 2013. Gas water production has exceeded our expectations and we continue to work with an existing gas buyer and our project partner PERTAMINA to achieve this goal.”

NuEnergy is now close to awarding a drilling contract to one of a shortlist of contractors with a view to committing to a two well development programme (with options to drill more) to complete the Muara Enim pilot production site. The drilling of the next two pilot wells is scheduled to commence in late July. Dewatering operations will continue in parallel with drilling operations for the next two pilot wells, which will be connected to the pilot site as they are completed.

As the pilot programme gains maturity, NuEnergy will work in co-operation with its off-take partner PT DPS to commercialise the pilot gas produced at the pilot site.

Current production at the pilot site is sufficient to generate on site power and offset operations costs in the order of US$2000 (€1500) per day. With a fully operational pilot plant on track for completion by year end, the forecast 1.5 million scfd of CBM production is expected to generate revenue in the order of US$15,000 (€11,000) per day.

“The company is now working to finalise well design and to secure a suitable rig to complete the remaining work on pilot wells at the Maura Enim pilot production site. Additionally, the NuEnergy exploration team has identified areas which are thought to contain very thick coals seams. These seams will be the target of NuEnergy’s exploration programme in 2014,” added ceo Christopher Newport.

Finally UK company Balltec has been contracted by Houston Offshore to supply and install ten MoorLOK subsea mooring connectors for the Tubular Bells project, located in the Mississippi Canyon area of the Gulf of Mexico.

The 15,000kN connectors will be used for mooring the Williams floating production system (FPS) Gulfstar GS1 at a water depth of 4500ft. The connectors, which are designed for both temporary and permanent mooring of floating structures, are due to be installed shortly.

The company also reports that it has successfully completed a MoorLOK contract for the Marine Well Containment System (MWCS) project. This is run by the Marine Well Containment Company as part of a system that can respond to a US Gulf of Mexico deepwater well control incident. The contract was awarded by Technip and involved enhanced connectors that use Balltec’s new helical connector as a secondary locking system. This in turn was developed as a result of extensive consultation between Balltec and Technip engineers in an effort to meet user demands for increased confidence and safety

Centrica ups production levels

Centrica’s latest management statement shows good news on production performance. The company says it expects total production from existing assets to be around 75 million barrels of oil equivalent (boe) this year, up from 67 million boe in 2012 – with higher gas prices bringing extra benefits.

Centrica has also acquired a package of producing conventional gas and crude oil assets in the Western Canadian Sedimentary Basin from Suncor, in partnership with QPI. The assets are expected to produce around 15 million boe in 2013 and the transaction is expected to close in the third quarter of this year. This is the first acquisition made under the memorandum of understanding signed with QPI in 2011 and Centrica says it is looking forward to further expanding the scale and scope of joint North American operations.

In upstream development projects, the company achieved first gas from York and Rhyl during the first quarter, while other approved projects at Kew, Grove, Valemon and Cygnus remain on track to bring 86 million boe of reserves into production over the next three years. In exploration, two out of three wells were successful in the first quarter. Drilling at the Rodriguez well in Norway in January confirmed the presence of gas condensate, while drilling at Whitehaven in the East Irish Sea in February confirmed a satellite field adjacent to the Rhyl reservoir.

The company has also announced a 20-year agreement with Cheniere to purchase 89 billion ft3/y of liquefied natural gas (LNG) volumes for export from the fifth train at the Sabine Pass liquefaction plant in Louisiana in the USA. The target date for first commercial delivery is September 2018.

Recent Issues