Exhaust Treatment

Wärtsilä has long been at the forefront of sustainable technology development. Just as cleaning wastewater or reducing air emissions are important contributors to a cleaner environment, engine efficiency is also central to sustainability. With years of experience in exhaust gas cleaning for marine applications, Wärtsilä has developed efficient, safe, and certified products for eliminating air emissions.

Our extensive reference list is evidence of our know-how and expertise in this field. With different size options, a minimized footprint, retrofit packages, and environmentally sound options, we are certain that we can find the right solution for any vessel. Our dedicated EGC team will assist you every step of the way; from initial planning to post-installation service agreements.


NOx Reduction

    Wärtsilä NOR

    Selective Catalytic Reduction, or SCR, is one of the few technologies capable of reducing Nitrogen Oxides down to the levels required by today’s most stringent regulations, and since year 1990 Wärtsilä has delivered hundreds of SCR systems. The Wärtsilä NOx Reducer (NOR) has been developed to enable vessels to comply with the IMO’s Tier III emission levels, while still maintaining a compact design optimised for marine applications. It is also available for land based installations and other NOx levels.


    The NOR is compatible with the entire portfolio of Wärtsilä 4-stroke engines. The technology has been developed and tested with Wärtsilä engines to ensure safe and flexible operation, and features an integrated communication system.  The product also works very well in combination with the Wärtsilä compact silencer and any of Wärtsilä’s scrubbing systems. Together, this forms a complete package comprising efficient energy production, silencing, and a full emissions reduction system. In addition to marine newbuild installations, the Wärtsilä NOx Reducer is used for retrofit installations and land based power plant applications.

    Tier III NOx standards

    The IMO’s Tier III regulations typically require SCR systems to be used with diesel operated engines. A marine diesel engine installed on a ship constructed on or after 1 January 2016, and operating in the North American ECA and the United States Caribbean Sea ECA, must comply with the Tier III NOx standards. Also starting from 1 January 2021 countries bordering Baltic Sea, North Sea and English Channel will form a NOx Emission Control Area. Earlier these countries have formed a SOx ECA since 2015. You can read more about the IMO rules at

    Local regulations

    There are other strong drivers for compliance, such as the US EPA rules for diesel boats and ships (, the Norwegian NOx tax, several inland waterway rules, and local discounts in port and fairway fees.


    SOx Reduction - Wärtsilä cares about your compliance

    The reduction of sulphur oxide (SOx) emissions from marine vessels has been a priority for quite some time now.  IMO regulations to reduce SOx emissions from ships first came into force in 2005, under Annex VI of the International Convention for the Prevention of Pollution from Ships – known as the MARPOL Convention.  Since then, SOx emissions have continued to be scrutinized. From January 1st 2020, the limit for sulphur in fuel oil used on board ships operating outside designated emission control areas will be reduced to 0.50% m/m (mass by mass). This will significantly reduce the amount of SOx emanating from ships, therefore bringing tangible health and environmental benefits for the world – particularly for populations living close to ports and major shipping routes.

    The main type of bunker oil for maritime vessels is heavy fuel oil, derived as a residue from crude oil distillation. Crude oil contains sulphur which, following combustion in the engine, ends up in ship emissions. SOx are known to be harmful to human health, causing respiratory symptoms and lung disease. In a study on the human health impacts of SOx emissions from ships, it is estimated that by not reducing the SOx limit for ships from 2020, the air pollution from ships would contribute to more than 570,000 additional premature deaths worldwide between 2020-2025.  In the atmosphere, SOx can lead to acid rain, which can harm crops, forests and aquatic species, and contributes to the acidification of the oceans. Therefore, through limiting SOemissions from ships one will not only improve air quality, but will also aid in protecting our environment.

    Wärtsilä has developed a full wet scrubber portfolio to fit each of our customer needs, and to meet their requirements in the reduction of SOx.  The range of Wärtsilä exhaust gas cleaning system (EGCS) have been tested and certified according to IMO guidelines, thus ensuring safe operation and compliance

    Wärtsilä continuously strives for technological excellence, and to minimize the environmental impact of our scrubber systems. 

    A Wärtsilä EGCS is a compliant solution for the entirety of your vessel’s lifetime

    The Wärtsilä EGCS body is constructed from over 50% recycled steel

    Our EGCS are engineered with the option to include wash water treatment units in order to ensure the safest possible discharge back to seawater.   

    In addition, Wärtsilä EGCS not only reduce SOx, but also remove large levels of particulate matter (PM) and black carbon

    Wärtsilä cares about the compliance of your fleet.  And we have made it easy for you to get exactly what you need – a compliant and environmentally friendly exhaust gas cleaning solution.  Contact our Sales Team today to find out more.

    «Are you ready for 2020»?

    2020 0.5% Sulphur Cap

    The year 2020 will mean a turning point for the marine industry, and also for worldwide shipping operations. The IMO has decided to introduce the global 0,5% sulphur cap in 2020, as planned. This means that all companies, independent of operation area, should start thinking about fuel and abatement options. Wärtsilä has extensive experience in marine market applications and with SOx scrubbing systems. We have the technology, the capacity, and the network to meet the challenge of a global sulphur cap. With a full wet scrubber portfolio, we can supply flexible and customized solutions for our customers, be it a single installation or for an entire fleet.

    Ask us about our Exhaust Gas Scrubber Solution for 2020. Customized for meeting 0.5% with possible savings in space, energy consumption and cost.

    Experience Counts

    Wärtsilä has more than 704 scrubbers delivered or on order for more than 535 vessels

    System Type
    Scrubber Type
    Vessel Type
    Statistics Reported: March 21st 2019


    Our Retrofit Services

    Wärtsilä Retrofit Services supports its customers throughout the lifecycle of a retrofit project by providing excellent engineering capabilities, by minimizing risks, keeping downtime to a minimum, and through reduced customer project management costs. As a professional project organization, we are capable of managing retrofit projects of all kinds wherever you are in the world, including EPC (Engineering Procurement and Construction), class and statutory approvals, commissioning, and crew training. Wärtsilä develops tailored retrofit solutions in close cooperation with the customer - from the very first enquiry until the system is successfully delivered and the project complete. By working very closely with the customer, we can establish the precise needs, and then validate the solutions at the conclusion of each phase of the project. After the project is completed, Wärtsilä’s global services network is there to support customers throughout the lifecycle of the ship.

    Read more about our retrofit services


    To scrub or not to scrub

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    The world of Wärtsilä Scrubbers

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    Smart SOx compliance 2020

    Wärtsilä has developed a modular installation system for sulphur oxide exhaust cleaning equipment that...
    1 October 2018
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    Exhaust gas cleaning systems are here...

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    9 August 2018
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    Trailblazers in exhaust gas cleaning...

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    Clean and clear

    Whether spurred by tightening regulations, customer demand or enlightened corporate policy, today’s shipowners...
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    Contact us

    EGC Scrubber Sales Team

    Heidi Paulsrud

    Heidi Paulsrud
    Director – Sales & Marketing 

    Christian Lobsgaard

    Christian Lobsgaard
    Sales Manager

    Kashif Javaid

    Kashif Javaid
    Sales Manager

    Sergio Rodrigo Palencia

    Sergio Rodrigo Palencia
    Sr Sales Manager – Cruise & Special Projects

    Marit Karstensen

    Marit Karstensen
    Sales & Marketing Coordinator

    Ole-Johan Øby Svendsen
    Heidi Paulsrud

    Ren Li
    Sales Engineer

    Aslak Suopanki

    Aslak Suopanki
    Manager – Sales Support

    Catalyst Team

    Jussi Uusipaavalniemi

    Jussi Uusipaavalniemi
    General Manager, Sales

    Jussi-Petteri Soikkeli

    Jussi-Petteri Soikkeli
    Sales Manager

    Jussi-Petteri Soikkeli

    Jussi Koljonen
    Sales Manager


    Contact us

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