Alfa Laval Pure Ballast System – Q&A

To explain more about Alfa Laval PureBallast System (BWTS), Scanunit prepared some questions and answers. Hope that will help to understand more about it. If you are looking for the installation team, don’t hesitate to contact us.

Alfa Laval UV reactors

When did Alfa Laval become involved in ballast water purification technology?

Alfa Laval company took the first steps to purify ballast water (BWTS) in 1997. The first Alfa Laval system was launched in 2006. With the ratification of the Ballast Water Treatment Convention, the time has come for shipowners to choose a ballast water treatment system that meets its requirements. On September 8, 2017, the convention enters into force, which says that every newly built and every existing ship will have to be equipped with a ballast water treatment system during the next IOPP certificate renewal.

Does the Alfa Laval treatment system meet all statutory requirements?

Yes, Alfa Laval is one of the first companies to boast a system that meets the requirements of both the IMO and the US Coast Guard.

How long did it take to certify the Alfa Laval system?

Alfa Laval system has had the IMO certificate for a long time. The efforts to obtain the USCG certificate lasted almost 2 years, which was related to the confirmation of the system’s operation in three waters: salt, fresh and brackish. Finally, on December 23, 2016, USCG approved our PureBallast 3.1 and 3.0 systems.

On what basis the size of the system is chosen?

The PureBallast system is selected based on the efficiency of the ballast pumps. Alfa Laval has systems from 150 m3 / h to even 6,000 m3 / h.

How does the Alfa Laval system work?

PureBallast 3.1 is based on the purification of ballast water by ultraviolet light. However, before the water goes to the reactor filled with UV lamps, it is initially cleaned by a very fine self-cleaning filter.

The reactor where the main purification takes place is filled with UV lamps, do such lamps need cleaning? Is this a complicated process for the crew?

Lamps, or more precisely quartz glass tubes, inside which the lamps are mounted, must be regularly cleaned so that the system maintains 100% of its efficiency throughout its lifetime. It is not recommended to clean the tubes mechanically in order to not lose their transparency. That is why Alfa Laval has developed a CIP (Cleaning in Place) module which, after ballasting and deballasting, cleans the entire reactor with fruit acids that are 100% biodegradable. The whole process is automated, and thus it is not complicated for the crew.

Do systems based on UV treatment have any operational limitations?

Yes, there are three main parameters that can limit the use of a UV system: water salinity, temperature, and UV light transmission. For the Alfa Laval system, there are no restrictions on salinity (including freshwater) and water temperature. When it comes to UV light transmission, which is measured during water ballasting, the Alfa Laval system is the market leader because it meets the requirements of the convention even at a low 42% UVT (UV Transmittance), which means it allows full ballasting even in heavily polluted waters.