Statoil prepares to take delivery of
Korean-built multipurpose tanker
The MST concept has been developed to provide maximum flexibility in the deployment of the vessel. The basic usage is likely to be as a shuttle tanker, transporting crude from a producing field to a shore terminal - as the world's leading operator of shuttle tankers, with a partly owned and partly chartered fleet, Statoil
Shipping and Maritime Technology should have plenty of work options for these vessels.
However, with minimum modifications, they can also be used as floating production, storage and offloading (FPSO) vessels, as floating storage and offloading (FSO) vessels, or for direct shuttle loading, thus obviating the requirement for dedicated field storage facilities.
A number of possible applications for the vessels as FPSOs is now under consideration. These include the Lufeng 22-1 oil field in China, where Statoil recently acquired Ampolex Orient's interest and operatorship, the Siri Field in Denmark and possibly on a joint development of the Tyrihans and Trestakk Fields off mid-Norway.
The FSPO version is well suited to the development of small and marginal fields which do not have the option of using existing infrastructure.
At the heart of the MST system is the submerged turret mooring system. By connecting to the vessel through its hull, the submerged turret enables operations to continue in the kind of adverse weather conditions which would cause a shut-down of operations employing a surface buoy.
Benefits of the submerged turret loading (STL) and submerged turret production (STP) systems include fast disconnect and reconnect of the vessel without external assistance, and maintenance of the buoy from the vessel, again without external assistance.
The compactness of the turret and the adoption of shipping industry design standards result in very favourable FPSO construction costs, Statoil says.
In the North Sea STL tankers are used to export crude from Statoil's Heidrun Field - one of these, owned by Conoco, was built by Samsung - and from BP's Harding Field. Others are used for storage purposes on Shell's Fulmar Field and Statoil's Yme Field.
Desulphurising technology lessens flow of
- Flowsheet of the H?S removal and disposal process: the disposal phase (right) can be based on any desulphurising method.
The technology, developed by ABB Environmental in Oslo, offers a low-cost solution for H2S disposal by simple incineration and sea water absorption. Statoil has already included it in its Aasgard development plan.
Other operators appear to be interested in the technology which could impact favourably the discussions on the effects of sulphur emissions offshore. Offshore gas desulphurising is in most cases necessary because of the corrosive effects of sour gas on pipeline steel. The new device can handle waste gas or tail gas with any H2S content from gas dehydration or gas sweetening units.
At the heart of the installation is an incinerator which is fed with the waste gas mixture, methane and air. A combustion residence chamber ensures that all H?S is converted to SO2. "We are able to do this and can at the same time prevent large NOx emissions," says Erik Wolff, ABB's system manager who is responsible for its further development. Waste heat recovery units can supplement heating onboard the platform.
After cooling, the flue gas is contacted with sea water and the SO2 is absorbed and converted to sulphite. In the presence of oxygen in the sea water, the sulphite will further react to sulphate which is a natural ingredient of the oceans. Studies by the University of Bergen have indicated that no harmful impact on the environment near to the unit's outlet could be traced during a five-year period.
The H2S waste gas disposal unit is, in fact, part of a larger project which also includes a desulphurising system integrated in the glycol dehydration process. This technology is based on a patent applied for by Norsk Hydro, and was tested on the Gullfaks A platform. To the glycol is added an amine which is capable of selectively reacting with H2S in the presence of CO2. The H2S can then be removed together with water in the subsequent stripping process.
A desulphurising unit of this type would offer a very economic solution for offshore platforms because of savings on space, weight and equipment. ABB Environmental is actively pursuing its further development, supported by operators including Norsk Hydro, Statoil, Phillips, and Saga.
A KAPOF project, concluded this March, showed that the process could treat gas with 30-500ppm H2S. ABB calculated that for an installation with 35ppm H2S and gas production of 10mcm/d, the technique could save the operator 50% of the cost in the second year of use rising to almost 80% in the fourth year.
Australia, Vietnam set trend for 3D seismic
PGS's Nordic Explorer seismic vessel is due to carry out a survey for BHP in the Timor Gap starting in October.
Petroleum Geo-Services' policy of concentrating its resources in the hi-tech 3D seismic market should pay off in the Far East as the market there evolves.
For the time being 2D seismic is still the norm in the region, but there is a growing interest in 3D seismic, according to Erik Haugane, PGS's Singapore-based project development manager. "So far 3D has been used almost entirely for development purposes," he says. "Now it's beginning to move back into the exploration phase, as happened in the North Sea."
In both Australia and Vietnam, recent licensing bids have involved work programmes based on 3D seismic offerings. "We're seeing movement from a well commitment to a 3D seismic commitment," Haugane says. "PGS can contribute to this trend by delivering 3D seismic surveys at a reasonable price."
The contractor recently sold the last of its 2D assets, and earlier this year took delivery of Ramform Challenger. This vessel, the second built to the unique Ramform design, is the most efficient and technologically advanced seismic vessel in the world, PGS claims; it is fully automated and equipped with 16 full size streamer reels, advanced streamer technology and a state-of-the-art on-board processing system.
For the time being there are no plans to deploy either of the Ramform vessels - the other is the Ramform Explorer - in the Far East. But in anticipation of a growing demand for 3D in the region, the company is expanding its capacity. In 1997 it plans to have 10 streamers in the region, up from five in 1995. Depending on how the market develops, capacity could be further increased, perhaps even doubled, in 1998. At present there is only one other contractor operating in the region with 3D capability.
Eventually PGS also hopes to sell time-elapsed 3D, often referred to as 4D, seismic services in the region. As yet there is little interest in this technology, which enables reservoir developments to be monitored over time. "Missionary work is still required in the Far East where 4D is concerned," Haugane says. "But it will definitely come in the future, and we are designing our service bearing this in mind."
PGS opened a representative office in Singapore in 1994 which was significantly expanded last year into a corporate regional office under the command of Dr William French, the president of PGS Asia Pacific. At the same time it signed a five-year cooperation agreement with the Bureau of Petroleum and Marine
Geology (BPMG) of the Chinese Ministry of Geology and Mineral Resources.
Under this agreement it will act as BPMG's technical partner for data acquisition, processing and marketing of non-exclusive 3D seismic surveys to be carried out in offshore areas which the bureau plans to open up to international licensing. The first project covers part of the Xi Hu (West Lake) depression in the East China Sea. As part of the agreement, PGS will exchange technology with BPMG and arrange the financing and management of individual projects.
PGS has just completed a ground-breaking 9,000-km regional and multinational 2D seismic survey referred to as the South-East Asia Supertie (SEAS). This is the first time that continuous data across license borders, national borders and disputed zones have been made available in the South China Sea.
The SEAS data links the major petroleum basins in the region - Malaysia's Malay and Sarawak Basins, Indonesia's Natuna Sea, and Vietnam's Nam Con Son and Cuu Long Basins. Two vessels, DMNG's
Zephyr and Digicon's Ross Seal, were employed on acquisition, which took place between April 1995 and January this year. The survey has proved an attractive proposition and so far 10 companies have bought SEAS data.
In October the company is due to start a minimum 1,100 sq km survey for BHP in the Timor Gap Zone of Cooperation between Indonesia and Australia. Data will be acquired by the Nordic Explorer fitted with five streamers. The vessel is currently working off Africa.
The contractor also has the one-streamer Odin Explorer working on a survey for Japex in Japanese waters, and then due to go to Shell on Australia's North-West Shelf. The 2D vessel will then pass to a new owner, as part of the 2D disposal policy.
The four-streamer Orient Explorer, which is owned by DMNG but has been rebuilt by PGS, is currently carrying out a large 3D survey for Esso in the Sea of Okhotsk. Since leaving the shipyard in Singapore in mid 1995, the vessel has also worked for Total and Enterprise in Vietnam, Shell in Brunei, Petronas Carigali in Malaysia. PGS plans to have the vessel dividing its time between the Far East, in the winter months, and the Russian Far East during the spring and summer.
Statoil considers FPSO tanker for first
operated Far East venture
(Top) Drill floor activity on Statoil's Bongkot Field in Thailand, where further expansion is under study. (Right) In Vietnam Statoil is involved in transport and infrastructure projects related to its offshore gas finds.Attention on Statoil's activities in South-East Asia is currently concentrated on China, where it is on the verge of deciding how to develop the Lufeng 22-1 oil field. Elsewhere in the region it is involved in a complex development in Vietnam and in gas production in Thailand. The company, which has interests around the world, sees its activities in South-East Asia as an important element in its ambition to become a leading international oil concern.
Statoil became operator of Lufeng 22-1 last year on acquiring the interest held by Ampolex Orient. Once the development concept is chosen, the China National Offshore Oil Co (CNOOC) will take a 25% interest, leaving the Norwegian company with the remaining 75%.
Lufeng 22-1 is a small oil field with reserves estimated at 26-36 MMbbl, which Statoil is understood to be planning to develop with a multipurpose tanker fitted out with production equipment, including a submerged turret production system. Under consideration for supplying the topsides package under lease is Advanced Production Systems (APS), a joint venture between Statoil itself and Aker.
A contract was recently let to the China Offshore Southern Drilling Co to drill five production wells using semisub Nan Hai 5 starting in late 1996. First oil is likely to flow in late 1997/early 1998.
The concepts of the multipurpose tanker and the leased topsides package have been developed by Statoil for small field development. The company has an interest in many small finds in Norway which are yet to be developed, but the concepts are equally applicable elsewhere, and could be put into practice for the first time on Lufeng. Such use would represent an important step forward in the search for ways to develop small fields profitably. As Lars Gunnar Dahle, public affairs manager for International E&P, says, "With
new technology we feel we can add value to this field and make it profitable. Five years ago nobody would consider Lufeng for development." The search for the best means of developing Lufeng has been conducted by a small team whose brief also covers the Connemara Field in Eire and Siri in Denmark - the three fields have modest reserves and appear suitable for floating production.
The Lufeng project represents a return to China for Statoil. During the 1980s it had some exploration and production activities and worked as a consultant to the Chinese oil company. It is now looking to expand its activities in the country, Dahle says. Earlier this year it opened an office in Shekou. State-owned but operating on commercial lines, Statoil follows the lead of the Norwegian government in deciding which countries it is not prepared to enter. China obviously is on the approved list - the Norwegian government encourages investment there. However, Myanmar is not, and earlier this year, after showing interest in the Yadana gas pipeline project, Statoil was obliged to issue a statement denying any present intention of becoming involved there.
The company has also become deeply involved in Vietnam, where it is present under the auspices of its alliance with BP, the latter taking the operator role. In 1993 and 1994 the partners discovered the Lan Tay and Lan Do Fields in water depths of 120-180 metres in block 06; Statoil's interest is 15%. Combined reserves are of the order of 57 bcm, Dahle says.
In the face of the complete lack of infrastructure for landing and utilising the gas, in terms of both physical facilities and legal/fiscal provision, the partners have now become involved in three separate projects related to these gas reserves: development of production facilities, installation of a 400-km
pipeline to shore, and development of a gas-fired power station and urea plant to turn the gas into products. As the only entities holding equity in all three projects, they are playing a key role in this stage of the country's industrial development.
The start of gas production is dependent on the power station, which is likely to come into operation, at the earliest, in late 1998. Offshore facilities are expected to comprise a production platform on Lan Tay, by far the bigger field, with a wellhead platform on Lan Do tied back to it, Dahle says. The gas will be piped ashore near the power station, which will be sited either at Phu My or Vung Tau.
North of the Lan Fields, Statoil and BP have another gas find at Hai Thach in block 5/2, on which an appraisal was drilled earlier this year. The partners have not revealed the size of this find, but it is believed to be commercial and could probably be exported to shore through the Lan Fields infrastructure.
In Thailand Statoil holds a 10% interest in the large Bongkot Field, from which it made its first operating profit in 1995. A further bout of investment could be coming up, as operator Total and its co-licensees study plans to expand output from 350 to 550 MMcf/d. Statoil is also the operator of an exploration licence in Thailand, and a partner on two other licences, operated by Total and Unocal.
Aker seeking entry into Natuna through
Indonesian venture partner
The White Tiger water injection module, an Aker EPC delivery, awaits transport to the field.
With a varied work experience in the Far East under its belt, Aker's latest move has been to position itself for Indonesia's Natuna project. It has established a cooperation agreement with Humpuss, a leading Indonesian industrial and trading group with interests which include LNG ship-owning, the processing industry, car manufacture and transport. Aker needs a partner if it is to chase work in Indonesia, and Humpuss's powerful position in the country's economy will benefit the joint venture, according to Knut Borgen, Aker Oil and Gas Technology's executive vice-president for international business development.
The Indonesian group is a new player in the oil and gas sector, but Aker can more than make up for that with its own extensive experience in supplying the offshore industry with goods and services. It is present in most major disciplines, from engineering and project management through fabrication, both of steel and concrete structures, hook-up and commissioning to maintenance and modification and eventual abandonment and disposal. One of its current concerns is the advance in deep waters, which has led it to become involved in such concepts as Spar platforms and the triangular TLP.
Concrete has fallen out of favour in the North Sea, but the company's subsidiary Aker Norwegian Contractors has been brought in to take over construction of the two small concrete-base platforms for Esso's West Tuna and Bream projects in Australia.
Aker's capabilities have expanded further following its recent merger with the Maritime Group to form Aker Maritime. The Maritime Group is itself also well established in the Far East.
Oil companies in the region, Borgen believes, are gradually moving away from the traditional contracting philosophy to embrace the current Western approach of integrated client/contractor teams, and allowing contractors sufficient freedom and responsibility to bring their creativity to fruition.
Aker being an all-round contractor, he welcomes this development, and hopes to see it brought to bear on Indonesia's giant Natuna project. "We want to find a way of getting involved in Natuna in such a way as to provide value-added, drawing on our experience in Norway and the US," he says. "A couple of the platforms will be big ones, with topsides perhaps as big as 35,000 tonnes. That's well beyond the previous size of platforms in the region, but within our experience in the North Sea. We're not interested in the small platforms, as the local industry can handle them."
Aker has already been involved in one interesting project in Indonesia, which pre-dated its involvement with Humpuss. This was a feasibility study for using a Spar production platform to produce a field in the 1,000-metre deep Makassar Strait for Pertamina and JNOC. Aker is 50% owner of Spars International, the sole supplier of Spar platforms. Spars International is currently delivering a platform to Oryx and recently won an order for Chevron's Genesis development in 800 metres water depth, both in the Gulf of Mexico.
Aker's agreement with Humpuss is not its first collaborative undertaking in the region. In Malaysia it has established joint venture activities with the Sime Darby group, including Sime Aker Engineering and Sime Aker Contracting, to carry out selected projects in that country. As a first step, Aker personnel have assisted on the fabrication of a 9,000-tonne topsides for Shell's MLNG Dua M3 gas development off Sarawak, the largest offshore structure yet handled by the Sime Sembawang Engineering yard in Johore Bharu.
Another Aker initiative which could bear fruit in the Far East is Advanced Production Systems, owned equally by Aker and Statoil, which proposes to build and lease out topside process equipment. In an era when the lives of many fields are too short to justify a large investment in production facilities, APS offers oil companies the advantage of hiring the equipment it needs for the time it needs it, while itself being in a position to benefit from its re-use. To maximise flexibility, APS has developed a modular equipment configuration with minimal interfacing. "We've designed it in such a way that it can be unbuckled and installed elsewhere," Borgen says.
APS has bid to supply process equipment to a number of projects, including Statoil's Lufeng 22-1 development in China. If Statoil opts to use a production ship - which is believed to be its preferred choice - then it will be equipped with an APS system, Borgen understands. In this case APS would subcontract fabrication of the equipment locally.
In Vietnam the contractor recently delivered a water injection module to Vietsovpetro's White Tiger project. This was a turnkey job in which Aker provided engineering and project management from London, with fabrication subcontracted to the Sembawang yard in Singapore and inshore hook-up and commissioning of the module carried out by its own staff at Vung Tau.
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