NETHERLANDS: The Scheldt River is a 7950 m³ dual-fuel (diesel and LNG) hopper dredger designed and built by Royal IHC in the Netherlands for DEME. It represents the latest in hybrid dredging technology with its “flex fuel” main engine capable of running on natural gas or light fuel oil. The dredger is part of DEME’s innovative Trailing Suction Hopper Dredger fleet.
With its ‘Green Passport’ and a ‘Clean Design’ notation, the vessel complies with the strictest international emission requirements. To help achieve these high standards, Danfoss was asked to contribute a drive solution that could boost an inboard dredge pump and increase energy efficiency with a small footprint, minimum weight and low volume - while being robust enough to withstand the harsh marine environment.
The modular VACON® 3000 Drive Kit qualified for the project for its ability to contribute to the vessel’s overall green performance and to offer the flexibility of design required by IHC’s engineers and technicians. This MV kit package enabled IHC to make their own customized, integrated solution, the IHC MV drive. Based on a modular approach, the compact IHC MV drive helps to save space and weight, optimizing the overall design of the vessel and its equipment.
When configuring and installing the VACON® 3000 drive, IHC was able to draw upon the experience of application experts in Danfoss Drives’ Marine Application Development Centre in the Netherlands. The centre is equipped with a range of testing and demo units, which were used to help and facilitate complete panel testing on load and customer FAT, together with IHC.
The keys to energy efficiency
The boosting of the vessel’s dredge pump with an AC drive was made possible through power take-in (PTI) technology, which allowed load sharing between the VACON*3000 and the main dual-fuel engine. This resulted in significantly higher energy efficiency.
Using transformer-less AFE technology employing normal water-cooling, the VACON® 3000 drive can run on lower supply frequency and voltage.
ACON® NXP LV drive modules are employed for other applications including pumps, thrusters and active filters. The switching of drive control between the inboard dredge pump and the submersible dredge pump of 1700 kW is performed by a medium voltage switchboard, where also the required sinus filter is located.
Replicating award-winning performance
The Scheldt River has been in operation since 2017, and in 2018, IHC was declared winner of the Maritime Award, ‘KNVTS Ship of the Year’, for taking a major step towards cleaner dredging. To continue setting new standards in environmental performance for the dredging industry, ship owners, DEME, have placed an order with IHC for an additional vessel of the same specifications, the dredger, Meuse River, which utilizes the same VACON® 3000 Drive Kit.
For more efficient operation and greater freedom in ship design, consider an electric-based main propulsion with engineering from Danfoss.