Built by Kraljevica Shipyard, Croatia, the ASPHALT SEMINOLE has been designed for worldwide service transporting cargoes requiring to be carried at temperature up to 250°C, including asphalt, bitumen, coal tar, coaltar pitch, coaltar naphta solvent and wood creosotes. The hull is laid-out with a wide double skin featuring large topside wing tanks, the line of which extends through the upper deck to form a trunk joining with a long forecastle. At midships the trunk is carried to the ship’s side in way of the manifolds, positioned above a pump room containing 2x400m3/h and 1x150m3/h hydraulic cargo pumps arranged to handle two grades of cargo simultaneously.
Within the cargo space, three holds are formed, each fitted with an independent prismatic cargo tank-block constructed of AH32 shipbuilding steel. No1 block (forward) contains a single tank, with No2 sub-divided into four tanks and No3 forming three tanks. All eight tanks can be used to carry heated or unheated products. Anti-rolling, pitching and floating keys support the blocks, and vertical “sandwich” supports (Feroform F3637 and Epocast 36 epoxy resin) are also provided. Insulation of blocks is by means of Rockwool mineral wood covered by aluminium foil. Water ballast is carried in the double-hull wing and bottom tanks, with bunkers carried in tanks forward and aft of the cargo space.
Two composite boilers are fitted to supply engine room needs and for heating bunker fuel, with two thermal oil heaters, each having an output of 1,200,000 kcal/h, satisfying the total heating load and giving thermal-oil temperature for cargo heating of 290°C (supply), reducing to 260°C on return, with oil circulation assisted by two 83m3/h pumps. The heating system is designed to maintain 250°C with seawater and ambient temperature conditions of 10°C and 0°C, respectively. In addition, cargo temperature can be raised by 10°C in one tank in 24hours under the same external conditions.
The vessel is powered by a Wärtsilä 8L32 diesel engine developing 4000kW at 750 rpm and flexibly coupled to a gearbox arranged to drive an alternator producing 1380kVA. Wärtsilä also supplied the shaft line and CP propeller giving a service speed at 85% MCR/15% sea margin of 13.4knots. Additional electrical supply comes from two Wärtsilä diesel alternator sets having an output of 1380kVA. The bow thruster is a 360kW unit, and a Becker flap rudder is fitted.
Length, oa: 108.50m, Length, bp: 99.90m, Breadth, mld: 18.60m, Depth to main deck: 10.60m, Draught design/maximum: 6.75/8.34m, Lightweight: 3660t, Deadweight design/maximum: 6494/9230dwt, Gross tonnage: 6292, Propulsion power: 4000kW, Service speed at 85% MCR, 15% sea margin: 13.40 knots.