A review of equipment recently specified for LNGCs shows that owners have established clear priorities in their choice of ballast water management systems, writes Paul Gunton
Judging by orders placed in the past few months for ballast water management systems (BWMSs) on LNG carriers, a range of technologies are considered suitable for this sector. Two orders in particular suggest that US Coast Guard (USCG) type-approval is a significant factor in the decision-making process for owners, as the US welcomes a rapidly growing traffic in LNGCs arriving to load export cargoes.
Meeting the USCG criteria
In the first contract of note the Greek BWMS maker Erma First secured a fleet-wide agreement from Norway’s Golar LNG in December 2017 to supply its USCG type-approved BWTS Fit system. It uses filtration, electrolysis and electrochlorination as its treatment method and the company said in a statement that its equipment would be installed “on up to 16 LNG vessels”, which potentially covers the whole Golar fleet.
Erma First BWTS Fit was the first full-flow electrolysis system to receive USCG type-approval and the Golar order came just two months after Erma secured USCG type-approval. Installations are due to begin during the company’s next drydocking and continue until the end of 2022, following Golar LNG’s drydocking schedule.
Erma First said it had worked intensively with the shipping company “over the previous months to optimise and adapt the system to the company’s vessels”. In the case of a previous contract that also benefited from cooperation with the customer, optimisation had involved specifying systems to suit each ship’s pumping, piping and other parameters, so that each installation could be completed within the ship’s normal drydocking.
The second notable order was announced a month later, in January 2018, by Alfa Laval of Sweden. Its USCG type-approved UV-based BWMS was specified by Nakilat, the Qatari shipping and maritime company with the world’s largest LNG fleet.
Few details were offered about when the Nakilat order was placed or which LNGCs are involved, but two of Alfa Laval’s PureBallast 3.1 systems of 2,000 m3/h will be retrofitted.
PureBallast 3.1 was selected, stated Alfa Laval head of PureBallast Anders Lindmark, for its small footprint, simple installation and ease of use.
USCG type-approval aspirants
Other systems that do not yet have USCG type-approval also claim to be well-suited for LNG carriers. US manufacturer NEI-Marine is working towards both USCG and IMO’s revised G8 type-approvals for its venturi oxygen stripping (VOS) BWMS.
This technology consists of an inert gas generator connected to the ballast line to strip the ballast water of all oxygen and kill the organisms in it. For LNG installations, a modification will allow it to use the LNG boil-off gas (BOG) to power the installation.
Coldharbour Marine in the UK also uses inert gas as one component of its treatment system and the company’s chief executive Andrew Marshall told LNG World Shipping that its target customer base is LNG carriers and tankers.
“Because of this focus, little training is needed to operate the system, since crews on those ship types are familiar with inert gas generators and the rest of its equipment is super simple and requires little or no maintenance,” he added. “As a result, the time taken for the crew to achieve full competency on the system is very short.”
Another option currently being developed for LNG carriers does not involve ballast treatment, or any ballast at all. French gas containment specialist Gaztransport & Technigaz (GTT), along with UK class society Lloyd’s Register (LR), China’s Dalian Shipbuilding Industry Corp and Belgian shipping company Exmar are developing a ballast-free LNG carrier design.
In December 2017 LR granted its ‘approval in principle’ to the design and this March the group began the next stage in their 30,000 m³ ‘B-Free’ LNGC initiative. Phase 2 of the project aims to develop the design further and validate results from the first phase by applying more detailed analysis and verification, including model testing.
For mid-size LNGCs such as this, ballast water is more critical to achieving sufficient draught for propeller immersion when the vessel is unladen than for stability. The B-Free design achieves this with a triangular-shaped lower part of the hull, allowing the vessel to sit deeper in the water when unladen, achieving the necessary propeller immersion for its 5.6 m diameter propeller while maintaining stability without needing ballast water.
The B-Free design is expected to have lower construction and operational costs than a conventional LNGC because there is no need for a BWMS.
USCG and IMO G8 approvals
As of 1 July 2018, nine BWMSs had achieved USCG type-approval while six more had applications pending. In addition, three manufacturers that had already secured USCG type-approval have applied for further approvals for modified versions.
The following paragraphs review the progress made by several BWMS manufacturers in their drive to secure USCG and IMO’s revised G8 type approvals.
China’s SunRui holds certificates for both the USCG and IMO testing standards for its BalClor system. Senior purchasing manager Helen Li said that the revised G8 guidelines “are more in line with the stringent USCG requirements” than the original guidelines. It already held USCG type-approval and “no major changes were needed to meet the revised G8 guidelines” she said.
Alfa Laval is the only other manufacturer to have gained G8 approval since the guidelines were revised. It too, has USCG type-approval for its Pure Ballast 3 BWMS and the company’s Anders Lindmark said that it had conducted the additional testing needed for a revised G8 certificate during 2017. When it received the certificate in February 2018, Alfa Laval became the first company to reach that milestone.
Other manufacturers that are working towards those goals have target dates that match the revised installation timetable agreed at the 71st Session of IMO’s Marine Environment Protection Committee in July 2017 (MEPC 71). For example, Bawat chief executive Kim Diederichsen said that he expects to receive revised G8 type-approval in Q1 2019, on the back of its USCG type-approval application.
Coldharbour, too, expects to complete its USCG testing this year, with G8 tests being run at the same time. This approach is the same as that taken by Wärtsilä. It submitted a USCG type-approval application for its Aquarius EC BWMS in early April 2018 and plans to match that for its UV version in Q3 this year. “Revised G8 requirements are being undertaken as part of our USCG testing schedules,” its BWMS sales director Craig Patrick said.
Hyde Marine senior market manager Mark Riggio indicated early 2019 as its target date for both USCG and revised G8 type-approvals. De Nora general manager Stelios Kyriacou, who is responsible for its Balpure business, is also aiming at early 2019, or late 2018, to submit revised G8 approval, having applied for USCG approval in March this year.
Ecochlor president Tom Perlich said that its USCG type-approval testing took place while the G8 guidelines were being revised. It obtained USCG approval on 31 March 2018 and said “we do not anticipate a need for separate testing” for G8.