Class societies are finding that operators have operational concerns with newly fitted ballast water treatment systems
ABS director and senior principal engineer William H Burroughs reports that substantial operating challenges lie ahead for those operators with retrofitted ballast water management systems. In its latest survey of almost 500 vessels installed with retrofitted ballast water management systems, the class society found the proportion of users who considered their systems to be ‘inoperable’ to have fallen to 6%, from 14% in a similar ABS audit from late 2017.
However, the number of owner/operators that reported their systems to be “operationally problematic” jumped to 59% from 29%. While this is a worrying trend, it also reflects the operational learning curve inherent in operating systems.
About 35% of the installed ballast water management systems on the vessels were deemed to be operational at the time of the survey.
That said, with compliance requirements already in force for US ballast water discharges and soon to be in force for more of the global fleet, owners and operators are still trying to gain critical experience with assorted ballast water management systems and the associated technologies.
In the survey, seven different types of ballast water management systems were examined, including those using:
The questionnaire’s findings, which were supported by a series of workshops conducted in New Orleans, Shanghai, Hong Kong, Singapore and Athens, included feedback from owners of bulk, gas, product, heavy-lift and vehicle carriers, as well as container ships.
The workshops shared the current best practices that support the integration of BWM systems, exploring the challenges of different technologies, ship types and sizes, operational and environmental conditions, operating frequencies, crew competencies and system-maintenance requirements.
Results varied among ballast water management technologies, but the feedback broadly revealed growing concerns among shipowners about the operational reliability of the systems, the operating expenses being as expected, the availability of vendor support, the quality of associated control software and adequate levels of crew training.
A high proportion of sales by Asian domestic manufacturers supplying local yards
The questionnaire often exposed lengthy periods for full adoption of ballast water management system technology, which suggests the need for owners to urgently start the selection process and for them to resist the temptation to make cost their sole criterion.
In addition to many crews being unfamiliar with the systems they were tasked with operating, the questionnaire and seminar feedback found widely disparate levels of technical support being offered by the vendors.
These findings in particular should encourage shipowners to assign at least one company engineer to participate in the installation process, and to operate it as much as possible before the compliance deadline to build corporate and crew familiarity. Owners of large fleets would also be well advised to nominate one ship as the training platform; more resources may have to be spent on operating and training for that ship, but it would help build operational reliability by familiarising other crews before they deploy.
Just over 70% of the vessels surveyed had their ballast water management systems installed during construction, against almost 4% having been retrofitted during drydocking. Almost one quarter did not reveal where their ships’ systems were installed.
Across all technologies, about one third of respondents were happy with the reliability of the systems they had installed.
Isolating with any certainty the predominant source of the perceived unreliability proved difficult, though, as it varied based on ballast water treatment technologies used. Certainly, post-installation vendor support has proven difficult to secure, particularly for owners domiciled outside the country of original manufacture.
Other feedback suggested that of the under-performance ratings for what is essentially new technology, some were attributable to the skillsets of the crews operating the systems. Some of the highest levels of dissatisfaction came from owners whose personnel received training ‘on the fly’ during commissioning, as on-board-acceptance testing was conducted.
About 40% of owners considered their systems to be ‘user friendly’, though given that this is a subjective evaluation, it is entirely possible that any two owners could judge the same treatment system from opposite sides of the spectrum. But the measure does speak to overall industry comfort levels with the technology.
Commenting on ABS’s efforts to assess the issues through its workshop and questionnaire, Crowley Maritime Corp director of engineering contracts Roy Choudhury said: “We commend ABS for taking the lead on this topic and facilitating dialogue on such a critical issue to the industry. By participating in the questionnaire and the workshop, we were able to hear from others in the industry who are experiencing similar challenges and share strategies that can benefit the broader marine industry, helping us all meet and achieve environmental compliance objectives.”
Time is running out for operators
ClassNK of Japan found a different but equally pressing set of issues in its own recent survey. In an analysis of the dates of expected retrofit of ballast water treatment systems among vessels under its class, it found that the data is heavily skewed towards 2022.
ClassNK found there are 7,315 ships on the ClassNK register that are obligated to install ballast water management systems in compliance with the BWM Convention by 2024. Of this number, 1,915 ships have completed the installation, leaving 5,400 ships that still require attention.
By the end of the years below, owners are obliged to retrofit ballast water management systems:
ClassNK warns owners and operators to submit vessels before the deadline to avoid a bottleneck in vessels requiring approval, although the class society also notes that in the case of some vessels, it may be uneconomic to retrofit ballast water treatment systems.
Domestication of ballast water treatment systems
There is very little data on the sales of ballast water treatment systems or complete ballast water management systems, but Lloyd’s Register (LR) has posted some data on its website that gives an indication of sales. An analysis of the data shows the importance of the relationship between domestic ballast water treatment technology manufacturers and shipyards.
According to Ballast Water Treatment Technology’s analysis of the LR data, approximately 70% of the recorded sales can be assigned to manufacturers that have a close link with shipyards. This indicates that the analysis is likely to be skewed by the number of sales linked to newbuildings in Asia. In the run up to 2024, there will have to be a surge in retrofits among the existing fleet, which may overturn the historical dominance of ballast water management systems from local domestic suppliers in Asia.
Retrofit advice
The surge in ballast water management system retrofits is going to be a challenge to operators and to class. To smooth the way, in March 2019 DNV GL issued a guide to approval of retrofit ballast water management systems installation on ships and offshore vessels.
Any retrofit of a ballast water management system starts with the impact on the engineering and pipework. DNV GL notes that the approval is dependent on an updated Pipework and Instrumentation Diagram (P&ID) that should include all the components and include details of the sampling port as laid down in the BWM Convention.
For electrolysis, ozone, heat treatment or de-oxygenation ballast water treatment systems, a separate P&ID is required showing the auxiliary systems. The arrangement of drip trays, ventilation, gas detection, pressure and temperature monitoring for tanks must be shown for chemical injection ballast water management systems. Any other type of system must show its auxiliary units and connections, too.
Under the BWM Convention a Ballast Water Record Book, an Approved BWM Plan according to D1 and/or D2 standard and an International Ballast Water Management Certificate must be kept on board, and for the approval of the retrofit DNV GL provides a Ballast Water Management template which operators can use to specify how the ballast water management system is going to be operated. It should reflect the changes made and include operational details such as filtration, pumps and limits on the use of the ballast water treatment system such as water salinity and temperature.
DNV GL requires that the operating manual is submitted separately along with the flag authority type-approval certificate. The commissioning of the retrofitted ballast water treatment system should take place with a DNV GL surveyor present, and any system using and/or producing hazardous chemicals must have a risk assessment submitted.
A retrofitted ballast water treatment system is going to draw power from the vessel; the amount required will depend on the system fitted. To achieve approval, DNV GL requires that the documentation detailing the changes to the electrical system be submitted as a single package. This will include details on how the retrofitted ballast water management system interfaces with the control systems on the vessel. The alarms connected to the control system will be tested by the DNV GL surveyor.
Operators should also be aware that if the ballast water treatment system is installed in a space redefined as a machinery space, then this space will have to be re-evaluated by DNV GL for fire safety.
The weight and the position of the retrofitted ballast water treatment system will have an impact on the trim and stability of the vessels. DNV GL notes that if the lightweight change exceeds 2%, then a new trim and stability booklet must be submitted for approval by DNV GL. This may require another inclining test. The mass of the new unit also has to be assessed, especially if there is an increase in deck loadings. DNV GL will require documentation on the foundation of the structure and the impact on the bending moment. Overall, a ballast water treatment system retrofit could require the submission of 40 or more documents and drawings.
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