Belgian Jan De Nul Group has ordered two 6000 m3 and one 18,000 m3 trailing suction hopper dredgers (TSHDs) to be built by Cosco and Keppel Singmarine.
Both hopper dredgers will have diesel-electric execution. This is exceptional for a hopper dredger as large as the 18,000 m3 vessel. All main drives, including the main propellers are electrically driven via frequency converters. In this way, each system runs at its optimal operating point, resulting in lower fuel oil consumption, and lower emissions.
Power is generated by three diesel-driven generator sets. A-symmetric load sharing, ‘fuel-mapping’, and automatically starting/stopping the engines in function of power demand is implemented. This again allows reduction of fuel consumption and emissions.
Exhaust Gas Treatment System
The dredgers will also be equipped with an exhaust gas treatment system. The SCR system reduces NOx emissions to the future EU Stage V level, which is more stringent than the requirements of IMO tier II and III. ‘Fuel-mapping’ makes it possible to select the operational regime of the engines; specific fuel consumption can be optimized in function of the loading of the engine, and in synchronization with the exhaust gas treatment system.
Sailing on Even Keel at All Loading Conditions
The 18,000 m³ vessel is equipped with a single suction pipe with a submerged dredge pump. The hopper is subdivided in two parts, enabling sailing on even keel, at all loading conditions. Two double-walled shore-discharging pumps with a total power of 14,000 kW are installed.
Cosco (Dalian) Shipyard Co.Ltd. will build the vessel in its shipyard in Dalian in China. Delivery is foreseen in 2020. Keppel Singmarine Pte. Ltd. will build two 6,000 Trailing Suction Hopper Dredgers in Singapore.
Main Characteristics of the 18,000 m³ Dredger
- Hopper capacity: 18,000 m³
- Deadweight: 30,000 ton
- Length o.a.: 166.1 m
- Breadth: 36.0 m
- Draught loaded: 9.75 m
- Maximum dredging depth: 86.0 m
- Diameter suction pipe: 1200 mm
- Pump power (trailing): 3400 kW
- Pump power (discharging): 14,000 kW
- Propulsion power: 2 x 7,500 kW
- Total installed diesel power: 22,540 kW
- Speed: 15.5 kn
- Accommodation: 32 p
Main Characteristics of the 6000 m³ Dredger
- Hopper capacity: 6000 m³
- Deadweight: 9880 ton
- Length o.a.: 111.7 m
- Breadth: 24.6 m
- Draught loaded: 7.0 m
- Maximum dredging depth: 35.0 m
- Diameter suction pipe: 1000 mm
- Pump power (trailing): 1500 kW
- Pump power (discharging): 4000 kW
- Propulsion power: 2 x 2150 kW
- Total installed diesel power: 7700 kW
- Speed: 12.5 kn
- Accommodation: 16 p
Picture by Jan De Nul.
