Abeko Marine received new requests for dredging and land reclamation projects, for which the company had to expand the fleet on the short term with a new Trailing Suction Hopper Dredger.
Suitable second hand dredgers were not available which made the company decide for the conversion of the MV ‘Sirocco’, a general cargo vessel built by Barkmeijer Shipyards, into a state-of-the-art Trailing Suction Hopper Dredger.
The design of the conversion of this former 3200-tdw vessel is executed by Conoship International in close cooperation with Barkmeijer Shipyards, Royal Niestern Sander and DredgeCon. The Conoship’s activities comprised the re-design of the General Arrangement of the vessel to a dredger, hullform modifications and watertight integrity.
To obtain more deadweight and to improve vessel stability, two sponsoons were fitted to the full midship length of the hull, enlarging the breadth from 12.50m to 16.00m. The cargo hold is redesigned into a hopper with bottom doors. Discharging can also take place through a rainbowing system on the bow or to a floating pipeline through a bow coupling.
Dry sand can also be discharged by an excavator that moves over the hopper area and transports the sand or gravel onto conveyor belts along the hopper to the shore conveyor.
Desalination and drying of sand and gravel is being done on board during the transits from the dredging area to the discharge port.
In the forward part of the original cargo hold a new engine- & pump room was designed, containing the dredge pump, jet pumps and two 400 kW azimuth thrusters. In the aft part of the original cargo hold another engine room is created with a second pair of 400 kW azimuth thrusters. Especially the additional four thrusters will give the vessel good manoeuvrability during operations in narrow harbour spaces.
The wheelhouse is elevated increasing the clear view on ship and environment during dredging operations.
This conversion proves the feasibility of creating a multi purpose Trailing Suction Hopper Dredger within a limited time span, based on a second hand general cargo vessel of good Conoship quality.
[mappress]
Dredging Today Staff, June 8, 2012; Image: conoship