The Wartsila NOx Reducer (NOR), an exhaust after-treatment system for removing harmful nitrogen oxide emissions from medium speed marine engines, has been upgraded with a new and improved design. The upgraded version features a flexible and more compact design to enable easier and faster onboard installation. It is also compatible for both marine diesel fuel (MDF) and heavy fuel oil (HFO) engine operation. The auxiliary units have also been improved; for example, centralised units for multiple installations with built-in redundancy are now available.
"The new version of the Wärtsilä NOx Reducer is designed for installation onboard newbuild vessels, as well as for retrofitting to existing ships. It not only enables compliance with existing and future legislation, but maximises the overall environmental performance and profile of the vessel, giving the change to profit from possible subsidizing bodies supportive emission reduction schemes. The upgraded design is in response to customer needs in the areas of installation flexibility, easy operation and maintenance, minimizing the impact on ship design while maintaining full flexibility on fuel selection," says Giulio Tirelli, Director, 4-stroke Portfolio & Applications, Wärtsilä Ship Power.
The Wartsila NOR enables vessels to meet the International Maritime Organisation's (IMO) Tier III NOx emission regulations, thus allowing them to operate freely within the current and planned Emission Control Areas (ECAs) designated by the IMO. Furthermore, Wartsila can optimise and deliver the engine and SCR as a fully tested, single package together with a Statement of Compliance for the IMO's Tier III regulations.
The Wartsila NOR system is based on selective catalytic reduction (SCR) technology, and can be operated together with other exhaust gas treatment systems, such as SOx scrubbers systems. The NOR reactor, which includes a soot blowing system and the catalyst elements, is available in a variety of shapes and sizes, and can be orientated either vertically or horizontally so as to optimise the use of available installation space. It can also be integrated with silencers.
At the Marine Environment Protection Committee (MEPC) 66 meeting in early April the IMO decided to maintain 1.1.2016 as the implementation date for the IMO Tier III NOx emission limits within the existing NOx Emissions Control Areas (NECAS). It was also decided to keep the implementation date flexible for future NECAS. This decision is based on the adoption date of a new NECA or, alternatively, agreement regarding later implementation dates during the designation process.
Technology for environmental efficiency
This latest innovation in emissions abatement technology offers ship owners a welcome opportunity to optimize operations, while at the same time meeting the need for environmental sustainability. Today, new and more stringent legislation concerning NOx emissions is a global phenomenon, and governing bodies like the International Maritime Organization (IMO) are introducing stricter regulations. Additional regulations in the shape of fees, taxes or incentive programmes, are being implemented by various parties, including individual countries that have introduced fairway dues, an NOx tax, or NOx fund initiatives.