Considerations on the safety of 2020 fuel blends addressed at IMO meeting
Confusion about whether the existing ISO 8217 marine fuel quality standard will cover fuel blends produced to meet the 0.50% sulphur limit has, hopefully, been cleared up at last week’s meeting at the International Maritime Organization.
Concerns about the safety of fuel blends complying with the upcoming 0.50% sulphur limit were on the agenda for the intersessional working group (ISWG) meeting of the Sub-Committee on Pollution Prevention and Response (PPR), which was tasked with developing guidelines to support the consistent implementation of the 2020 sulphur limit.
Some documents submitted to the meeting stated that these fuel blends would not meet ISO 8217 specifications, and cited safety concerns including stability, compatibility, cold flow properties, acid number, flash point, ignition quality and cat fines. IBIA has already explained that the current SOLAS flashpoint limit and existing ISO 8217 parameters will still apply to fuel blends produced to meet the 0.50% sulphur limit, or they will be ‘off-spec’ and hence not commercially viable.
IBIA was encouraged to hear several delegations at the IMO meeting last week also highlighting that ISO 8217 already addresses most of the safety concerns raised. In particular, a statement made by ISO, represented at the meeting by the Chair of the technical committee in charge of the ISO 8217 marine fuel standard, said the 0.50% fuel oils “will be fully capable of being categorised within the existing ISO 8217 standard.”
Moreover, ISO explained that the Publicly Available Specification (PAS) which the ISO 8217 committee expects to develop and finalise prior to 2020 will provide guidance as to the application of the existing ISO 8217 standard to 0.50% sulphur fuels.
One of the key concerns expressed in the market is the stability of fuel blends, as it has been pointed out that some blend components – especially if mixing aromatic and paraffinic refinery streams – would increase the risk of the final blend being unstable. ISO pointed out to the meeting that fuel oil blenders and suppliers should take careful note of these consequences ensuring this fuel characteristic is not overlooked. That statement is in line with IBIA’s “Best practice guidance for suppliers for assuring the quality of bunkers delivered to ships” published earlier this year, in particular under Chapter 4.2 – Quality control during production of bunkers.
One element that ISO 8217 cannot address, however, is compatibility between different blends ordered by ships. Compatibility between pure distillate fuels is not an issue as they do not contain asphaltenes, however for blends containing residual fuel oils, ship operators need to be fully aware of the potential for different batches of fuel being incompatible. Just like the case is today, it will not be possible for suppliers to guarantee compatibility as blend formulations will vary widely, hence ships will, as they do today, have to consider the risk of incompatibility. The ISO representative told the meeting: “Recognising that some degree of mixing of different fuel oils onboard the ship cannot be avoided, many ships today have already procedures in place to minimise co-mingling of fuel oils with bunker segregation being always the first option. We would therefore encourage ship operators to evaluate further their segregation policy.”
Some of the safety considerations surrounding fuel management under the 0.50% sulphur limit have been addressed in guidelines developed at last week’s meeting for the planning and preparatory stage, which will be forwarded to the 73rd session of the IMO’s Marine Environment Protection Committee in October for approval.
A more comprehensive document containing guidelines of a more operational nature to help operators manage both distillate fuels and fuel oil blends containing residual fuel will be developed at PPR in February next year for approval by MEPC 74 in May, 2019.
Several elements that may be included in ship operational guidance were described in documents submitted to last week’s meeting, however, it was agreed to take up an initiative by OCIMF and IPIECA to establish industry guidance that addresses the impact on fuel and machinery systems resulting from new fuel blends or fuel types with guidance on the handling, storage and use of such fuels. They have engaged with organisations including as CIMAC, the Energy Institute and ISO to develop such guidance and have invited other interested parties to join. IBIA has taken up the invitation.
Report by Unni Einemo