Ballast water treatment
answers are here

When planning for a ballast water treatment system, there are many questions that need to be asked. Here you will find answers to common questions, both about Alfa Laval PureBallast 3.1 and about the legislative issues surrounding ballast water treatment.

Alfa Laval PureBallast 3.1 – FAQ

The differences between Alfa Laval PureBallast 3.1 and other systems are easy to explain and difficult to ignore. No other system comes close to its capabilities.

1. Why is PureBallast 3.1 pure confidence – in all waters?

Simply put, PureBallast 3.1 provides fully compliant ballast water treatment without limiting your vessel’s operations or freedom of movement. Type approved by both IMO and the U.S. Coast Guard, it can perform:

This unique combination of capabilities ensures that you have a full range of options. Your ballast water treatment system will never restrict the place or manner in which you do business

Added to this is the uncompromising construction of PureBallast 3.1. Built with non-corroding 254 SMO steel, PureBallast 3.1 reactors can be expected to last up to 20 years or more without replacement.

2. How does PureBallast 3.1 technology differ from that of other UV-based treatment systems?

Many of the alternatives actually have their roots in drinking water treatment. Because they are adaptations of land-based technologies for water purification, they are less suited to common marine circumstances such as low UV transmittance. By contrast, the enhanced UV treatment technology in PureBallast 3.1 was developed specifically for marine use.

In PureBallast 3.1, the reactor’s UV lamps are combined with specially designed lamp sleeves of synthetic quartz. As well as optimizing the breadth of the wavelength spectrum, the sleeves have a high transmission efficiency that results in more UV light during disinfection. Combined with the flow-optimized design of the reactor interior, they ensure optimal UV dosage and low energy consumption.

Supporting the enhanced UV treatment is an extremely effective filter stage, which removes any larger organisms and particles prior to biological disinfection. Together, the filter and reactor stages enable full-flow treatment of fresh, brackish and marine water with UV transmittance as low as 42%. No other system can match this performance.

3. Why is a Cleaning-In-Place (CIP) cycle a part of PureBallast 3.1?

Without some form of cleaning, deposits of calcium carbonate and metal ions will build up on the quartz sleeves of the UV lamps in a ballast water treatment system. This will impair treatment, since less of the UV light produced by the lamps will be able to pass through.

Mechanical wiping is an alternative to CIP, but wipers are ineffective against the build-up of metal ions, which must be removed with a low-pH fluid. Nor do they clean the UV sensor within the reactor, which measures the UV transmittance. If the sensor and quartz sleeves are dirty, the system may use more power than necessary or be otherwise poorly controlled.

Any form of mechanical cleaning – including manual cleaning – will also lead to sleeve scratches. Eventually, these too will degrade the treatment performance.

Simply put, tests have shown that CIP has a valuable role in maintaining the biological disinfection performance of a ballast water treatment system. In a UV-based system, the effects are noticeable after a single cleaning operation. Moreover, by reducing energy use and maximizing the lifetime of the quartz sleeves, CIP has a long-term role in keeping operating costs down.

4. Is PureBallast 3.1 easy to install and operate?

The answer is yes, in both respects.

PureBallast 3.1 is an inline system in which the major components (filter and reactor) are incorporated into the ballast water piping. The reactor diameter, in particular, is only marginally larger than that of the piping itself.

This creates an easily retrofitted system with a small footprint and high flexibility. Free placement of the lamp drive cabinet up to 150 m away allows further space savings in the engine room, as well as placement outside the hazardous zone for Ex systems. For smaller vessels, PureBallast 3.1 can even be delivered as a skid-mounted, plug-and-play solution with the market’s smallest footprint.

Because no salt or chemicals are used, there is no need for additional tanks or ventilation systems. Nor is any manual intervention – such as the opening and closing of valves – needed from the crew. Operation is fully automatic and started or stopped with a push of a button, either via the graphical touchscreen interface or via the vessel’s Integrated Ship Control System.

5. How efficient is PureBallast 3.1?

Efficiency can refer to two things in a ballast water treatment system: biological disinfection performance or energy consumption. In practice, however, these things go hand in hand.

In terms of biological disinfection performance, no system is more efficient at neutralizing ballast water than PureBallast 3.1. Only PureBallast 3.1 can perform in all water types and in water with UV transmittance as low as 42%. This it can do at full flow, i.e. without reducing the speed of ballast operations.

Because of its high performance, PureBallast 3.1 is also highly energy efficient. In most situations, it can run at just 50% of its potential operating power. Only when needed, for example in waters with extremely low UV transmittance, is it ramped up to its full installed power.

Ballast water treatment legislation – FAQ

Ballast water treatment has been discussed for many years. Now that the IMO Ballast Water Management (BWM) Convention has been ratified, the issue has become urgent worldwide.

1. Why should I decide on a ballast water treatment system now?

Now that the BWM Convention is entering into force, there is no time left to wait. Even if your vessel has just had a renewal survey, it will need to have a ballast water treatment system retrofitted by its first renewal survey after September 2017. This will take more time and resources than many ship owners expect, so early commitment and good planning are keys to success.

In essence, all vessels will have to install a treatment system within a period of around five years. As a result, there will be a tremendous demand for systems and shipyard slots. Literally thousands of vessels will be competing for both supplier and shipyard capacity.

Many suppliers lack the production strength to scale up in the coming years, or the experience to ensure smooth delivery and installation with the many parties involved. For you to receive a compliant system in time, you must choose a supplier who is able to do both.

If you need to deballast in the United States, you must be even more selective in your choice. In order to comply with the U.S. Coast Guard (USCG) Ballast Water Discharge Standard, which became law in 2012, you need a system that is specifically approved for use by the USCG.

2. Why should I look for a recent type approval certificate?

The BWM Convention serves as the main international guideline for ballast water treatment systems. However, it was established when far less was known about the control mechanisms needed for ballast water treatment. As the application has evolved, so has IMO testing, becoming more uniform and stricter.

IMO type approval certificates issued since 2014 may offer more detail about the Operating limitations of a system, such salinity, temperature and UV transmittance levels. Certificates issued before this date should be examined critically and the newest revision of a certificate should always be sought.

The USCG type approval system was designed much later and with transparency in mind. USCG type approvals, which have been issued for a handful of systems to date, offer a solid indication of system capability.

3. Why should type approval tests be conducted by an authorized third party?

Type approval testing by an authorized third party is important to ensure transparency, validity and ultimately system compliance. Third-party testing bodies can ensure a controlled testing environment and realistic test conditions, which will prevent system deficiencies from being overlooked.

For example, organisms that live near the water surface have a much higher tolerance for UV light than those that live deeper down. To neutralize these organisms effectively, medium-pressure UV lamps are needed. But by using a cultivated mixture that excludes these organisms, it is possible to meet requirements while cutting corners technologically.

Today much has been learned about the control mechanisms needed to ensure compliance. Serious suppliers choose robust UV technology, seek third-party transparency and perform their tests with water that contains naturally occurring organisms, as Alfa Laval has done with Alfa Laval PureBallast 3.1.

4. What does the possibility of Port State Control inspections mean for me?

Inconsistencies in IMO type approval have led to growing demands for a control mechanism. Spot checks have been proposed, in order to ensure that IMO-certified treatment systems do their job in actual operation. Naturally, the responsibility for the checks would fall to Port State Control.

In reality, this raises as many questions as it does answers. For example:

  • Should a vessel that fails a spot check be allowed to perform ballast water exchange?
  • What should otherwise be done with a vessel that fails its spot check?
  • How should a spot check be performed in practice?

Given the time and practical difficulties involved, even stricter IMO testing would be preferable to spot checks. However, ship owners and ship operators must be prepared for the possibility of spot checks and ensure that their treatment systems actually perform in reality.

5. Why is ballast water treatment legislation necessary?

The choice of a ballast water treatment system is yet another large decision in planning a new vessel or retrofit, as well as an added expense. But without ballast water treatment, there would be an even greater price to pay.

Invasive marine species are not simply a nuisance. They are identified as one of the greatest threats to our oceans today. Each year they cause billions of dollars in damage by destroying fisheries and other marine businesses, and in many cases they impact business and commerce on land. At times, they have even cost human lives. (Specific examples can be found here.)

So while ballast water treatment may seem an unwelcome addition to the marine industry, the consequences of not taking action are even less desirable.

Stay updated about ballast water treatment

Subscribe to our newsletter
Alfa Laval has 10 years of experience in ballast water treatment. Through our newsletter we will keep you aware of important developments, regulation updates and much more. Subscribe today and stay informed.