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5. Coastal, Offshore and Ocean Space Utilization
Deep Sea Drilling Vessel
The deep sea drilling vessel "Chikyu" of the Japan Marine Science and Technology Center (JAMSTEC) was launched in January 2002. The vessel can reach a maximum water depth of 4,000 m and drill to a maximum depth of 7,000 meters from the seabed, where it can pick up sample cores. Capitalizing on this capability, the vessel will play a central role in the international Integrated Ocean Drilling Program intended to elucidate the mechanism of major earthquakes and changes in the crust and climate of the earth, discover microorganisms deep underground and reveal the origin of life. To effectively serve its mission, the vessel is intended to be a drilling ship for scientific purposes meeting the highest global standards, equipped with a deep sea riser for new drilling techniques and a new type dynamic positioning system (DPS). After undergoing hull outfitting and the installation of the DPS and the drilling system, it is scheduled to be completed in 2005.
 
FPSO and FSO
Floating production storage and offloading units (FPSOs) and floating storage and offloading units (FSOs) having no crude oil production facilities have come into extensive use in recent years, replacing fixed platforms of the conventional jacket structure. The FPSO "Kerr-McGee Global Producer III" de-livered in October 2000 is intended for operation in the North Sea, where it will be faced with an extremely stringent marine environment. Using a single-point mooring system relying on an internal turret at the center of the hull, it has an oil storage capacity of 550,000 bbl (about 87,500 m3). The FSO for Vietsovpetro uses an external turret, positioned outside the tip of the bow, has an oil storage capacity of 1,086,000 bbl (about 172,700 m3). This FSO was delivered in an extremely short period of only 13 months from the time the contract was signed until the installation in its operating site in the South China Sea. The eight point-moored FPSO "MV8 Langsa Venture" delivered to Matrix Oil for service in the Langsa oilfield off the Island of Sumatra, Indonesia, is a conversion from a tanker, an expedient often resorted to when the delivery deadline is very short. Its crude oil production capacity is 15,000 bbl/day (about 2,400 m3/day) and oil storage capacity, 272,400 bbl (about 43,300 m3).
Note: The metric expression is only for supplementary reference (1 bbl = 0.159 m3.)
 
LPG-FPSO and LNG-FPSO
In the development of ocean energy resources, too, it is required to minimize impacts on the environment. In this connection, an LPG-FPSO/FSO has been developed and is now under construction for the purpose of putting associated gas, which is developed in the crude oil production process, into commercial production instead of flaring it. This FPSO has an LPG separation plant on deck, and the capacity of its SPB type LPG tanks is 135,000 m3, the largest for offshore storage of LPG. It is also proposed to apply this technology to offshore production facilities and offshore receiving terminals for LNG, and prospects are rising for its adoption from the viewpoint of national security in addition to its expected environmental benefits. Incidentally, the principal dimensions of the LPG-FPSO are 230 m in overall length, 49 m in breadth and 28.8 m in depth.
 
Deep Sea Drilling Vessel
 
TLP
The tension leg platform (TLP) for El Paso Energy was installed in July 2001 in Prince Field in the Gulf of Mexico. The maximum operable water depth of this TLP is about 450 m, its loading capacity, about 4,000 tons, its daily production capacities, 25,000 bbl (about 4000 m3) of crude oil and 55 million ft3 (about 1.5 million m3). This is a slim size TLP known as the MOSES type, developed for use in a smaller scale oilfield to be fixed with eight tendons* to the seabed.
*Tendons are steel pipes for fixing a floating structure, which constitutes the main body of a TLP to the seabed. They are installed so as to always keep the legs subject to the buoyancy of the floating body.
 
Autonomous Underwater Vehicle (AUV)
The deepsea cruising vehicle "Urashima AUV-EXI" of the Japan Marine Science and Technology Center (JAMSTEC) is a prototype of the next generation undersea robot, which can engage in unmanned submarine navigation without support from any mother ship to collect seawater specimens and survey the seabed surface among other observatory assignments. lt is designed to be able to stay underwater for a long period continuously to accomplish extensive surveying of the Arctic area. The "Marine Bird" is another prototype capable of engaging in under water assignments of long durations by autonomously docking at a station installed on the seabed or a large submarine vessel to have its batteries charged.
 
Mega-Float for Floating Airport
The Mega-Float technique is one of the candidates for use in the planned project for re-expansion of the Haneda Airport in Tokyo, along with reclamation and pier (jacket) construction. Japanese shipbuilders and steelmakers worked together in the six-year Mega-Float project from April 1995 onward in the hope of realizing a floating airport. Under the guidance and with the cooperation of the Ministry of Land, Infrastructure and Transport (MLIT), the project was successfully completed in March 2001. In this R&D project, a floating body for basic research, measuring 300 m in length, 60 m in breadth and 2 m in depth, was built for the three-year first phase, and a floating airport model of 1,000 m in length, 60 m (partly 121 m) in breadth and 3 m in depth was built for the second phase also of three years. Both were installed in the Bay of Tokyo for use in experimental and theoretical studies in a wide variety of technological areas such as design technology including the analysis of elastic responses in waves, fabrication technology for the construction of the Mega-Float split into huge structural units, offshore construction technology to enable welding of floating units on the heaving sea surface, technology for confirming the soundness of the structure against the impacts of aircraft taking off and landing, technology for long endurance against corrosion by seawater and technology for environmental assessment embodying possible implications from occupying a vast area of sea surface. The aircraft takeoff and landing experiments at the final stage of Phase 2 endorsed the practicality of the floating airport.
 
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Experiment for Mega-Float as Data Backup Center
After the completion of research oriented toward the Mega-Float as a floating airport, a floating body of 200 m in length and 100 m in breadth, made up of the previous 1,000-m long experimental structure which were cut off and joined together, was used in a national project to check the applicability of the Mega-Float concept as a floating information technology (IT) data backup center. The project was intended for eventual structure of a mutual backup system to distribute the vast possession of electronic information to different localities in order to prevent their total loss in the event of any major natural disaster. The findings of the experiment demonstrated that the steel structure of the floating body or its shaking or vibration would not adversely affect computers and other equipment mounted on it. As part of this project, the National Maritime Research Institute, using the same experimental floating body, measured stresses occurring in its structural details in waves, and thereby reconfirmed the effectiveness of the method of fatigue strength analysis applied to the Mega-Float.
Incidentally, this floating structure was towed to the Port of Yokohama to serve as the venue of a music event to celebrate the eve of the World Cup Soccer opening, and accommodated an audience of some 10,000. Moreover, the Phase 2 floating body was cut into different sizes and are being reutilized as piers, fishing ponds and other purposes.
 
Extended Studies On Mega-Float
Making use of the basic technical knowledge on pontoon type Mega-Floats accumulated through Mega-Float research projects, the Corporation for Advanced Transport & Technology (CATT), an organization associated with the Ministry of Land, Infrastructure and Transport (MLIT), coordinated studies on different versions of the Mega-Float by universities, national research institutes and business corporations. Structures of various types tentatively designed in this process were all found applicable to practical purposes. These versions included 1) a Reef-type Mega-Float which would utilize natural topographies including reefs and be moored in a shallow reef where it would be exposed to severe steep waves, 2) Semisubmersible Mega-Floats including a coastal type and an offshore type, 3) an "Eco-Float" which would absorb wave energy into itself and utilize it for electric power generation, and 4) a "Subplate" type Mega-Float with an underwater flat plate, which would be moored alongside the main floating body to perform breakwater function.
 
Floating Disaster Relief Facility
The Hanshin-Awaji Great Earthquake which occurred in January 1995 involved the collapse and destruction of many roads, bridges and buildings, and created great confusion in land traffic. This experience re-endorsed the effectiveness of a sea-based support system using floating facilities in such a major disaster. Following this recognition, floating disaster relief facilities were installed in the Bays of Tokyo, Ise and Osaka to serve as support bases in such calamities. These facilities are substantially similar in size, and the floating body moored in the Bay of Tokyo measures 80 m in length, 25 m in breadth and 4 m in depth.
 
Demonstrative Experiments for Utilization of Ocean Resources
Marinoforum-21 has undertaken a five-year R&D project since fiscal 2000 to create fishing grounds by utilizing deep sea water. A demonstrative model of ocean fertilizing plant for use in this project is scheduled for installation in fiscal 2003. This test plant capitalizes on technology regarding the diffusion of density current and technology developed, together with its track record, for ocean thermal energy conversion (OTEC). With the goal of discharging fertilized seawater, it is intended for experiments to proliferate plant planktons and thereby enrich the sea in edible resources by pumping up sea water with a high content of nutritious salt from a depth of 400 to 500 m and mixing it with water in the photic region of about 30 m deep from the surface. This plant measures 213 m in overall height including a riser, with its main body including a water discharge outlet at the top measuring 16.8 m in height, and displaces 1,700 t of water. When moored in a sea of 1,000 m in depth, it will have a capacity to pick up 100,000 m3/day of deep sea water and 200,000 m3/day of surface water.
 
Ocean Fertilizing Plant Utilizing Deep
Sea Water (Main Body)
 
Facilities for Prevention of Marine Pollution
A drag suction dredge-cum-oil skimmer ship "Hakusan" was built, and stationed at the Niigata Port, Harbor and Airport Office. It is a 4,200 gross tons vessel, equipped with two 500 m3/h broadside-arranged oil skimmers, one 250 m3/h casting oil skimmer and a 1,500 m3 recovered oily water storage tank, and has a reel-type oil collecting boom with an extensible outrigger.
A drain treatment facility for reclamation disposal plant was installed off the coast of Kobe. This facility is used in a state in which, after it is moored within a reclaimed shore protection, the protection is closed and intercepted from the open sea. Having a function to treat filthy water within and continuously discharge the treated water, it has a daily treating capacity of 4,200 m3.







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