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The IMO global sulphur content cap-one year on

Andrew Bates, Head of FD&DTeam Asia

in this article Andrew Bates looksat the experience of the industryfollowing the introduction of the0.5% sulphur content limit formarine fuel oils and, later, Dr ReneMacahig provides some valuableinsights into quality andperformance issues.

A smooth transition

The implementation of the new sulphur limit went a lotsmoother than many in the shipping industry hadpredicted. In terms of availability, producers such asExxonMobil, Total, Shell and BP were marketing very low0.5% sulphur fuel oil (VLSFO) well in advance of January2020 and there was a stockpiling of such fuels at strategicpoints around the world, such as Singapore. Furthermore,the softening of global crude prices in December andJanuary helped to ensure a smooth transition.

Compliance

In terms of compliance, reports present a relativelypositive image. For instance, statistical data from theTokyo MOU Asia-Pacific shows that so far this year onlyfive detentions were reported in connection with thesulphur content of fuel used on board, and these five wereall reported before the end of April 2020. Statisticalinformation published online by the Paris MOU shows thatthere were no violations reported concerning Annex VI.

The COVID-19 effect

The COVID-19 pandemic in 2020 has undoubtedlyimpacted on the ability of port state control (PSC)authorities to conduct physical inspections of vessels.For instance it had been anticipated that PSC officerswould board vessels using portable sulphur contentanalysers, conduct documentation checks, and physicallycheck SOx emissions in exhausts using sniffers, as wellas test samples taken directly from the fuel oil storageand supply system of a ship with increased frequency.Such ‘in use’ samples are separate from the statutoryMARPOL sample taken at the time of the stem. Notsurprisingly, there is anecdotal evidence that the ability ofPSC officers to implement such measures in the climateof COVID-19 has been reduced.

Variances in testing

MARPOL also contains provisions relating to a 95%‘confidence limit’, to consider the variances associatedwith testing of ‘in use’ fuel oil samples. This means thatwhen such samples are taken by PSC and analysed forcompliance a sulphur content of up to 0.53% must beaccepted as compliant. This helps ensure that shipoperators are not unfairly penalised for marginal excessesdue to factors beyond their control. Bunker suppliers arenot, however, accorded any confidence limit and arerequired to stay at or below 0.5%.

In the months following the introduction of the sulphurcap the Club saw instances of the BDNs declaring the fuelto be less than 0.5% whereas subsequent testingproduced results above it (usually marginal increases of0.02% or 0.03%). In all cases the fuel was eventually

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Maritime shipping is still the mostcarbon-efficient form oftransporting goods, far more sothan road or air transport. Theintroduction of the sulphur contentcap by the iMo under MARpoLAnnex vi in January 2020 furtherenhanced the benefits globalshipping has for the environmentcomparative to other modes oftransport.

on 1 January 2020 the new globalsulphur limit for marine fuelsbecame 0.5% by mass, reducing itfrom the previous 3.5%. To broadlyillustrate the difference this makes, aship burning 37 tons of 3.5% fuelwould emit 2.2 tons of sulphur oxide(Sox), whereas with 0.5% fuel theemission is reduced to just 0.36 tons.

Regulating and reducing shippingemissions is central to the climatechange agenda of greenhouse gasreduction. Cleaner marine fuelsproduce cleaner coastal air andreduce ecological damage, inparticular from acid rain.

Dr Rene Angelo Macahig,Consulting Scientist, Andrew Moore & Associates, Singapore

A consulting scientist with AMA based inSingapore, Rene is an expert in chemicalanalyses and instrumentation, and has givenadvice in multiple fuel quality disputes.

consumed without any unwelcomeconsequences. That takes place withina regulatory framework where the BDNis the primary evidence of compliancewith MARPOL. However the risk willalways remain that on some futureoccasion PSC will test the MARPOLsample retained on board and that maynot produce results reflective of theBDN.

The FONAR

Most ship owners will already befamiliar the Fuel Oil Non-AvailabilityReport - the FONAR. Part of thescheme of Annex VI (see regulation 18)is that when facing enforcement actiona ship owner should be able to fullydocument efforts to achievecompliance. This information isembodied in the FONAR, and it is to bepresented to the flag state and the portof destination in advance of a call.

In the early stages of 2020, the Clubobserved some cases of shipownershaving to chase a time charterer (whois contractually responsible forsourcing and supplying compliant fuel)for updates on the bunkering situationin anticipation of the possibility of filinga FONAR. It caused frustration forsome members and is an example of

the tension that can exist betweencommercial realities and statutory(MARPOL) compliance.

Pricing

IMO 2020 was expected to push upbunkering costs and disrupt marketsbut investment in desulphurisationplant and blending by refiners,combined with severe demanddestruction from COVID‐19, has meant that prices for low sulphurproducts have only risen modestlycompared to high sulphur fuel oil. Thepremium for VLSFO had fallen fromover USD 300 per ton in January toabout USD 70 per ton by mid‐June.Weaker global trade because of thepandemic has reduced demand formarine fuels generally.

Quality and usage issues

In the run-up to the 0.5% sulphur cap itwas anticipated that the characteristicsof VLSFOs could vary considerably,given the wide range of residue streamsand cutter stocks expected to be usedas blend components. Fuelcharacteristics such as density andviscosity were expected to vary widelyand, indeed, compliant bunkerscustomarily ordered as RMG 380 grade

currently exhibits a broad spread ofviscosity values.

Stability

Marine fuel oils are complex mixturesconsisting of a wide spectrum ofdifferent molecules, from simplehydrocarbons to large complexasphaltenes. A fuel oil mixture can beconsidered as a multi-phase system inwhich the asphaltene, aromatic, andsaturate fractions are kept in balance,meaning it is ‘stable’ fuel.

Thermal stresses or changes in thechemical properties can lead toinstability, and may ultimately result inflocculation (by which fine particulates

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Prices for lowsulphur productshave only risenmodestlycompared to highsulphur fuel oil.

are caused to clump together) anddeposition of asphaltenes. In fuel oilthese asphaltenes are generallystabilised by aromatic components.However, the increased use of paraffinicblend components to meet the morestringent sulphur requirement for newcompliant fuels can affect the stabilityof the resulting blend leading to a higherrisk of breakdown and sludging. Highlevels of sludge formation can causefiltration and separator issues in fuelsystems, hence ISO 8217 includes aspecification requirement for fuelstability, termed as Total SedimentPotential (TSP). It is the responsibility ofthe fuel supplier to provide stable fuelscompliant with ISO 8217 requirements.

There are many alleged contaminationcases where the bunkers are found to bewithin specification for the routine ISO8217 parameters but, when put into use,machinery problems occurred. Typicallythe most common problem is filtersclogging and needing replacementalong with certain other parts. The resultis not so much material or engine failurebut a more troublesome experience forthe crew in running fuel through theship’s system, and the purchase ofexpensive fuel additives and spareparts.

Viscosity and pour point

Low sulphur fuel can have viscositiesnear or at the lower limits of allowedviscosity. As more distillates enter theVLSFO blend pool, fuel viscosity hasfallen, a trend that has been widelyreported by most testing houses. Whilstthe lower viscosity values may notnecessarily be off specification, thereare nonetheless important operationalimplications to be considered. Forexample, it is essential that the viscosityat the fuel injectors remains within thelimits prescribed by the engine maker.When the viscosity is too low, it maylead to inadequate dynamic lubricationof fuel injection equipment and poordistribution of the spray pattern in thecombustion space.

Some VLSFOs may exhibit relativelyhigher pour points which would meanthat higher transfer temperatures,typically 10˚C above the pour point, arerequired to facilitate pumping. At thesame time, the crew would need to

closely monitor the viscosity of the fuelsuch that it does not fall below theminimum set by the engine makers. Acombination of low viscosity and highpour point, though not necessarily offspecification, could present operationalchallenge.

Cylinder lubrication

Prior to the introduction of the 0.5%sulphur cap engine parameters were setup to use residual fuels with anexpectation that fuel sulphur contentwould typically be in the range of 2.0 to3.5%. With the use of VLSFOs, however,the neutralising demand on the enginelubricants and cylinder oil becomesmuch reduced. The base number (BN) oflubrication oil should be carefullyconsidered for extended operation withVLSFOs and should be referred to theengine maker. Too low or too high a BNleads to operational issues. Shipownersare advised to engage with theirlubricant suppliers and follow originalequipment manufacturer (OEM)guidelines to ensure that the appropriatelubricants are being used with respect tolow-sulphur fuels.

Sampling

Fuel quality disputes will often involvetesting, and hence the provenance andintegrity of the samples to be tested isand remains of great importance. Asidefrom dispute resolution, suitably drawnand witnessed representative samplesof the fuel also form the basis forcompliance verification under MARPOL.Properly drawn representative samplesare particularly important for potentiallyunstable fuels, as the sediments mightsettle to the bottom of the cubitainerduring drip sampling.

A team effort

The introduction of the IMO 0.5%sulphur cap under MARPOL has beenconsiderably more seamless than manyobservers had anticipated. Theenvironmental and health benefits fromthe reduction of SOx emissions are clearand it is perhaps fair to say that IMO2020 has been a success,notwithstanding the adversities ofCOVID-19 restrictions. Industryparticipants will need to remain awareof the various operational aspects of

VLSFO usage and the characteristics ofthe fuel, as described above. Crewmembers will need to be particularlymindful of the correct procedures forstorage, handling and operation. Fortheir part, time charterers will need tosource fuel where blend componentsconform to the ISO 8217 standard. Inshort, in order to avoid the sorts ofproblems described in this article, theresulting fuel must be a homogenousblend, and able to withstand theexpected forces through normal onboard use and storage.

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It is perhaps fairto say that IMO2020 has been asuccess,notwithstandingthe adversities ofCOVID-19restrictions.