Jan De Nul Group, a Luxembourg based dredging, offshore, civil and environmental company, has ordered three trailing suction hopper dredgers (TSHDs).
Cosco Dalian Shipyard Co. Ltd. will build the 18.000m³ dredger in its shipyard in Dalian, China, with the delivery set for 2020.
According to Jan De Nul’s announcement, two 6.000m³ TSHDs will be built by Keppel Singmarine Pte. Ltd in Singapore.
“These compact and medium-sized vessels are provided with features making it the best in their class for efficiency and emissions, ” said Robby de Backer, Director Newbuilding Department.
Lower fuel oil consumption and lower emissions
These hopper dredgers are in fully diesel-electric execution. This is exceptional for a hopper dredger as large as the 18.000m³ vessel.
All main drives, including the main propellers are electrically driven via frequency converters. In this way each system runs at its optimal operation 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 the power demand is implemented. This again allows reduction of fuel consumption and emissions.
Exhaust gas treatment system
In addition to these measures, an exhaust gas treatment system is installed. 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 IMO tier III.
‘Fuel-mapping’ allows us 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.
The 18.000m³ 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.