Page 64: of Maritime Reporter Magazine (June 2003)

Tuna Farming Goes Offshore

Izar Fene Shipyard, in collaboration with Itsazi

Aquaculturehas, has developed an Offshore unit for the breeding, fattening and transport of the bluefin tuna (Thunnus Thynuus). Sailing at eight knots, the unit is able to transport (e.g.) living tunas from the

Mediterranean to Japan.

The proposed Tuna Offshore Unit combines a unique fish farming facility with a modern marine design to produce an offshore unit capable of purchasing young

Tuna Fish in the selling centers, fattening of 1,200 tons of tuna fish in nine months in hot water areas improv- ing the efficiency of the growing process. Upon com- pletion, the fish are then presented to the fish markets at best prices. Other aquatic species such as salmon, bass, cod, se bream, hake, etc, could also be produced.

The 603 x 184 ft. (190 x 56 m) facility resembles an offshore semi-submersible unit with a catamaran hull and an internal arrangement of a 394 x 167 ft. (120 x 51m) fish-pool of 95,000 cu. m. that can be expanded in operation up to 195,000 cu. m. capacity by deploy- ing a rigid net for fish cultivation. A big effort was completed in the definition of the hull forms to achieve an optimum hydrodynamic behaviour capable of matching the target transit speed of eight knots. It was also necessary to take care of the transverse moment of inertia of the waterplane at the operation and transit draft by means of seven floatability columns, in order to provide adequate stability performance.

In the forward area, the forepeak and ballast tanks are located within a rounded hydrodynamic bow.

Below the centerline floatability column, a forward machinery space is arranged containing a 900 kW retractable thruster. Tunnels are also arranged to accommodate two centerline anchors. Above the cen-

Main Particulars • Tuna Offshore Unit

Length, o.a. 603.6 ft. (189.4 m)

Breadth 183.7 ft. (56 m)

Height to Floater Deck 88.6 ft. (27 m)

Height to Main Deck 154.2 ft. (47 m)

Draft (minimum) 32.8 ft. (10 m)

Draft (Transit/Mooring) 121.4 ft. (37 m)

Lightship weight

Ballast water

DO.

Fresh water

Fridge

Fish Pool Volume (net retracted)

Fish Pool Volume (net deployed) 181 130,000 cu. m. 10,000 cu. m. 1,000 cu. m. 10.000 cu. m. 95,000 cu. m. 195,000 cu. m. terline floatability col- umn, the accommoda- tion block is placed with capacity for 30 people and a helideck.

Two large 5,000 kW thrusters have been arranged in the aft area, together with the power plant located in the aft machinery space. The exhaust system of almost 20 MW power plant is guided to the outside through the aft stability columns, containing also ventilation funnels, escape routes and elevators.

Storage and daily use diesel tanks, lube oil, fresh water, ballast water and settling tanks are also placed within the aft machinery space. Finally, the emergency generator set is confined within a deckhouse in the aft- starboard stability column, in accordance with marine regulations. The Tuna Offshore unit is equipped with two conventional offshore cranes located in the mid- body columns and adequate life saving appliances.

The basic design of the Tuna Offshore Unit, including machinery and services, has been designed in agree- ment with typical Offshore Regulations (DNV, ABS,

Lloyd's, BV, etc). IMO and Spanish regulations have also been taken into account (ILCC, SOLAS, COL-

REG, Tonnage, etc)

Power and Controls

The Main Power Generation is located in the Aft

Machinery Space. The plant consists of 3 x 6,750 kW -fifi m a pr tlffeM I

Izar Fene and Itsazi Aquaculture has launched an innova- tive venture to build a system to raise and transport tuna offshore. (50 Hz-750 rpm) main generator to be used during transit, and one 1,080 kW essential services generator to be used in operation when the unit is moored during the fattening period. An 810 kW emergency generator set and associated switchboard is arranged in a deck- house above aft-starboard stability column within the accommodation block, within a separated fire-rated enclosed space complying with the applicable Rules and Regulations. The IAS will be distributed through the vessel by means of dual-redundant data-highway routed along the main deck between the aft engine control room. System application and logic will be res- ident in dedicated intelligent process stations located within the vessel in order to minimize the use or hard- wire cables. In critical systems, where higher reliabili- ty is required, consideration is given to having redun- dant central process units within the process station.

Circle 242 on Reader Service Card

MADCON Receives

Patent For Retrofit

System

MADCON Corporation, Slidell, La. has received official notice that their Structural Composite

Retrofit System has been awarded U.S. Patent

Number 6,536,991. Improved recovery and directional drilling techniques created the need to extend the original design life of many off- shore facilities. Utilizing advanced composite materials, the system provides full structural restoration of damaged or corroded tubular members such as drive pipe casing, conduc- tors, jacket legs and bracing, concrete or steel piling, and risers/pipelines. The system can also be used to upgrade the original design capacity of platform members.

The Structural Composite Retrofit System can restore and protect a severely corroded mem- ber without costly shut-ins due to hot work.

MADCON employs highly specialized person- nel, including divers, so the system can be installed both above and below water. Several major offshore owner operators recently installed the Structural Composite Retrofit

System from the (-15) to (+60) elevation to rebuild extremely corroded drive pipe casing.

Circle 56 on Reader Service Card

Kvaerner Masa Marine

Naval Architects - Marine Engineers

Soq^jxgsffiiDg) ®)© (MMiajeQBiboairg? #207-1525 West 8th Ave.

Vancouver, B.C.

V6J 1T5 Canada

Tel: (604) 736-8711

Fax: (604) 738-4410 #202 - 201 Defense Hwy.

Annapolis, MD 21401 USA

Tel: (301)970-2226

Fax: (301) 970-2230 fPtU http://www.masamarine.com 202' PSV for Naviera Tamaulipas

Under construction at Bender Shipbuilding & Repair

Mobile, Alabama 64 Maritime Reporter & Engineering News