MAN Diesel & Turbo signs contract with Sembcorp Marine to supply dual-fuel solution for new semi-submersible crane vessel
MAN Diesel & Turbo has signed a contract with Sembcorp Marine in Singapore to supply the dual-fuel propulsion system – including exhaust-gas after-treatment – for a New Semi-submersible Crane Vessel (NSCV) for Heerema Offshore Services, the company said in its press release.
The scope of the contract – signed on 30 October, 2015 – provides for 12 × MAN 8L51/60DF four-stroke engines + 12 × MAN SCR (Selective Catalytic Reduction) systems. MAN Diesel & Turbo states that the total power output of the engines is some 96 MW and believes it – with the exception of power barges – to be one of the largest engine installations the world has ever seen aboard a single ship. It is the first vessel of this size to feature dual-fuel technology and, upon completion, will be the largest vessel of its kind globally. Engine delivery is scheduled for Q1, 2017 with vessel delivery due in Q4, 2018.
This highly efficient package ensures full fuel-flexibility and meets NOx Tier III emission limits at all times – whether within Tier III zones or not – both during operation on LNG, as well as during operation on MGO with the help of the SCR system. MAN Diesel & Turbo states that the engines maintain their high efficiency – also during SCR operation – through integrated and customised control strategies.
A key determinant in the choosing of the 51/60DF engine was its ability to fulfill the particularly high load-ramp requirements demanded by the NSCV’s giant 2 × 10,000 ton cranes in both diesel and gas modes while maintaining its efficiency.
Another key characteristic of the four-stroke unit is its ability to operate at 100% MCR and above, in gas mode, and to switch smoothly and seamlessly from gas to liquid-fuel operation (and vice versa) at full load without any fluctuation in output or speed. These are all essential features to satisfy the NSCV’s vital DP-3 (dynamic positioning) station-keeping requirement.
Furthermore, with the aim of becoming the most environmentally friendly crane vessel ever built, operation will be on ultra-low sulphur fuel, a fuel type that the 51/60DF readily handles.
The prospect of individual countries and regions designating so-called Emission Control Areas (ECAs) in advance of the IMO Tier III starting date is now a reality with the first NOx ECA* being the U.S. and Caribbean Sea from January 1, 2016 and more to follow.
MAN Diesel & Turbo’s SCR system provides an integrated solution for its entire portfolio of four-stroke engines and serves as a standard solution to meet Tier III emission limits.
The SCR system is available in fourteen different sizes, in this way fully covering its entire portfolio of medium-speed engines. For the design and development of the MAN SCR System, MAN Diesel & Turbo brought together a diverse range of competences.
Special system features include:
- communication with the engine control system that optimises the temperature for the SCR system at individual load-points
- integration of the SCR control system into the overall engine control system
- adaptation of injection control from MAN with electronic fuel injection
- general system reliability.
The MAN SCR solution is a modular system, with the built-in flexibility to adjust to the NSCV’s particular requirements such as its long exhaust-gas lines, the distance between the SCR and engine. Nor does the SCR system negatively affect load-ramp requirements. In this respect, MAN’s SCR is very much a customised solution.
With a length of 220 metres and a width of 102 metres, the NSCV will be the world’s largest crane vessel.
When the new vessel enters operation, MAN Diesel & Turbo will be able to lay claim to powering several of the largest vessels in the offshore segment.
About Heerema Offshore Services
Heerema Offshore Services is a subsidiary of Heerema Marine Contractors (HMC), a world leading marine contractor in the international offshore oil and gas industry. HMC excels at transporting, installing and removing offshore facilities. These include fixed and floating structures, subsea pipelines and infrastructures in shallow waters, deep and ultra-deep waters. The company is headquartered in Leiden, the Netherlands.
About Sembcorp Marine
Sembcorp Marine provides innovative engineering solutions to the global marine and offshore industry, drawing upon more than 50 years of track record. It focuses on four key capabilities, namely, rigs & floaters; repairs & upgrades; offshore platforms; and specialised shipbuilding. Sembcorp Marine operates shipyards strategically located in Singapore, India, Indonesia, the United Kingdom and Brazil.