Ballast water treatment

Type approved by IMO and the U.S. Coast Guard, Alfa Laval PureBallast 3 offers superior performance in all waters – fresh, brackish and marine. It saves space in new vessels and simplifies retrofits in legacy fleets.

Ballast water treatment

Pure confidence – in all waters

Alfa Laval PureBallast 3 is the third generation of the leading ballast water treatment technology – and the first solution to be revised G8 ready. More than 3200 PureBallast systems have been sold to date, including hundreds installed as retrofits. Alfa Laval PureBallast 3 has the backing of a well-prepared supplier. Large-scale production resources, strong partnerships and a well-developed service offering make Alfa Laval the confident choice in ballast water treatment.

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Our solutions meet both global ballast water treatment requirements and those of the U.S. Coast Guard (USCG).

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Be ready for new legislation

Since ratification of the IMO Ballast Water Management (BWM) Convention, new-builds need treatment systems installed at delivery. After September 8th 2019, existing vessels will have to retrofit.

Ship owners who need to deballast in United States waters have even more issues to consider.

The decisions you make now are vital to the success of your business for years to come.

Leadership that matters

We have the knowledge and resources to help you succeed in complying with the BWM Convention or USCG legislation. Our flexible PureBallast 3 offering ensures you get the best and most cost-effective system for your specific needs.

We have been involved in developing ballast water treatment standards including IMO and USCG type approvals. We've fitted over 1,700 PureBallast systems, more than 600 of them retrofits, so you know you're in safe hands.

Certificates & Approvals

PureBallast 3 is certified by all major classification societies. See which ones.

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Read success stories about some of the more than 1,700 PureBallast systems we have delivered so far.


Find your system

Your choice of ballast water treatment system needs to be a perfect match for your vessel, ensuring smooth operations and unfailing compliance with environmental legislation. With Alfa Laval PureBallast 3 you can be certain of both.

Select for the long term

Your ballast water treatment system should last – and provide lasting resale value.

Choose reliability

Make sure your ballast water treatment system lasts as long as your vessel by choosing key components that won't corrode in seawater conditions.

A UV reactor is a pressure vessel that may need replacing in five years if built with a steel grade like 316L. PureBallast 3 reactors are built with super-austenitic stainless steel, expected to last 20 years or more.

Where the vessel can sail will affect potential buyers, as well as what they are willing to pay. They also value equipment from a recognized supplier who they can count on for long-term support worldwide.

Completely secure ballast water treatment

Alfa Laval PureBallast 3 is the dependable choice. A reliable product backed up by a large global organization. We have served the marine industry for a century and have been involved in ballast water treatment since it was first proposed.

Choosing a ballast water treatment system

Download our 11-point selection guide that will help you choose the system that’s best for you.


The leading supplier and system

PureBallast is the most established choice in ballast water treatment.

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A history of leadership

We have been involved with ballast water treatment for more than a decade, developing treatment technology. We have provided biological and technical expertise on key panels to develop standards and educate the market.

Developed in cooperation with Wallenius Water, PureBallast is a mature system at the forefront of ballast water treatment. The original system was launched in 2006 and was the first commercially available treatment solution.

Widely sold and widely trusted

More than 1,700 PureBallast systems have been delivered and commissioned. Hundreds of PureBallast systems have been installed as retrofits, and installations performed worldwide at a diverse range of shipyards and vessel types: container ships, tankers, bulk carriers, offshore supply vessels, naval vessels and more.

Total support worldwide

We have a complete range of solutions for new-build and retrofits. Our large-scale production is ready to meet your needs as the BWM Convention comes into force.

Shipyards and engineering companies get clear, thorough documentation and expert consultation. We offer best-in-class support including Performance Agreements.

Get everything you need, from advice to parts and service, anywhere in the world.

Orders received

We have received PureBallast orders for different vessel types from all over the world.

Vessel types served

    • Anchor handling tugs
    • Bulk carriers
    • Car carriers
    • Coastal ferries
    • Container feeders
    • Container ships
    • Cruise ships
    • Drill ships
    • General cargo vessels
    • LNG carriers
    • LPG carriers
    • Naval vessels
    • Offshore supply vessels
    • Research vessels
    • River liners
    • RoRo vessels
    • Shuttle tankers
    • Supply vessels
    • Tankers

Ballast water treatment legislation

Ballast water treatment regulations are now taking effect. The IMO Ballast Water Management (BWM) Convention has been ratified and U.S. Coast Guard (USCG) legislation is already in force. We have the knowledge and a decade of experience to help you navigate the regulations impacting your vessel.

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The USCG Ballast Water Discharge Standard

The USCG Ballast Water Discharge Standard has been in force since June 2012. As of December 2013, all new vessels wishing to deballast in United States waters must comply, with requirements for existing vessels following.

During an initial period, certain IMO-approved systems have been approved for use in United States waters as Alternative Management Systems (AMS). Due to the availability of treatment systems with USCG type approval, IMO systems installed after 7 March 2017 are no longer given AMS approval.

Systems submitted for USCG type approval must currently be tested according to the CMFDA/FDA staining method. The systems must be well developed when testing is performed, and the tests must be conducted by an independent third party. This degree of transparency adds credibility to the test results.

There are more specific requirements on the monitoring of operating parameters during USCG tests.

To date only a handful of ballast water treatment systems have received USCG type approval, including PureBallast 3. Future acceptance of the most probable number (MPN) testing method, which is more appropriate for UV-based systems like PureBallast 3, would possibly allow the continued use of some systems approved as AMS today.

The IMO BWM Convention

Adopted in 2004, the BWM Convention is known officially as the International Convention for the Control and Management of Ship's Ballast Water and Sediments. Though it took many years to ratify, its introduction triggered the development of today's range of treatment systems.

Since its ratification in September 2016, the BWM Convention has made ballast water treatment a major issue worldwide. As of September 2017, newbuilds require type-approved treatment systems, while existing vessels need to have them retrofitted according to the revised IMO implementation schedule. Vessels operating in US waters that have passed their compliance date need to treat the ballast water with a BWMS if discharging in US waters.

Because the BWM Convention was established when less was known about the control mechanisms needed in ballast water treatment, IMO type approval certificates have developed over time. Certificates issued after 2014 offer more detail about the operating limitations of a system, such as salinity, temperature and UV transmittance levels. Any certificate issued before this date should be examined critically and seek the newest revision of a certificate.

Today the BWM Convention is interpreted in a uniform way by third-party testing bodies worldwide, who strive to ensure a high degree of transparency in all testing procedures.

Ballast water treatment legislation

Since the IMO Ballast Water Management (BWM) Convention was ratified, the issue of ballast water treatment legislation has become urgent worldwide, raising questions in the industry.

Alfa Laval PureBallast 3 and IMO revised G8 guidelines

The following questions and answers explain the implications of Alfa Laval PureBallast 3 type approval according to the revised G8 guidelines.

Retrofit PureBallast 3

Alfa Laval is prepared for the technical and logistical challenges of retrofitting a vessel for ballast water treatment.

Tailored retrofit solutions

On most vessels there is no existing space or consideration for ballast water treatment. The compactness and flexibility of PureBallast 3 Compact Flex simplifies a retrofit.

We customize each project to meet your requirements, offering budgeting assistance and financing options.

Cooperation and flexibility

We can work with your engineering department and chosen yard, or secure expertise from our own network for engineering support, 3D laser scanning, class approval and more.

We can meet your existing docking schedule or arrange for installation during your voyage. As a global organization with strong logistics, we can move with your project if your trading routes change prior to docking. Our presence and capabilities worldwide ensure a smooth and successful project, even when major changes occur.

Download Retrofit leaflet

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Turn to us for ballast water treatment

Ready to take the next step towards an Alfa Laval PureBallast 3 system? We would love to provide more information or a quote for your specific vessel.

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