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VPS: Why do VLSFOs still require quality considerations?

VLSFO play an important role, comprising 55% of marine fuel samples; while no official ISO8217 specs exist, VLFSOs demand careful management due to unique properties.




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Steve Bee, Group Commercial & Business Development Director of marine fuels testing company VPS, on Thursday (18 August) shared that in the pursuit of greener shipping, the shipping industry should not overlook the importance of quality fuel management for traditional fossil fuels. 

Very Low Sulphur Fuels (VLSFO) play an important role, comprising 55% of marine fuel samples. While no official ISO8217 specs exist, VLFSOs demand careful management due to unique properties:

As the world of shipping quite rightly focuses on reducing its carbon footprint and endeavours to comply with a host of decarbonisation legislation, it may be easy to forget that traditional fossil fuels are still the main energy source for the majority of the global fleet. As such, the fuel management of fossil fuels and their quality, continues to be an important factor in protecting vessels, their crew and the environment.

As the most widely used fossil fuel, Very Low Sulphur Fuels (VLSFOs) require more focus than others, in terms of their fuel management. VLSFOs currently account for 55% of all marine fuel samples received by VPS for fuel quality testing. There are still no official standard specifications within ISO8217 for VLSFOs.

As such, most VLSFOs are tested against the RMG380 specifications, knowing that the viscosities of VLSFOs in particular, are very much lower than 380cSt. Currently, 68% of all VLSFOs tested have a viscosity between 20cSt-180cSt. This can have a significant impact on the transfer and injection temperatures onboard a vessel, requiring much less heating of the fuel to achieve the optimum injection viscosity. It would be beneficial to see the introduction of a minimum viscosity specification limit for VLSFOs, as well as a current maximum viscosity limit within ISO8217?

Currently 3.8% of all VLSFOs tested have at least one off-specification parameter. This compares favourably with the off-specification rates for HSFO fuels at 11.4% and MGO fuels at 16.9%. However, the VLSFO off-specifications are potentially more concerning than some of those associated with HSFO and MGO. Sulphur, water, cold-flow properties and cat-fines are the most frequent of VLSFO off-specification parameters.

Screenshot 2023 08 21 at 1.47.56 PM

Sulphur off-specification is the most common of all VLSFO off-specifications, with over 30% of all off-specifications being attributed to this one parameter. However, recent test results have shown that sulphur off-specification is certainly better today than it was back in 2021, with only 1.6% of VLSFOs tested being >0.50% Sulphur compared to 2.4% >0.50% in 2021.

Also, it would appear that so far this year, suppliers are producing more fuel in the 0.41%-0.46% Sulphur range, than the 0.47%-0.50% range, than over the past two years, which means that there is less chance of the VLSFOs falling outside of the 95%-confidence interval, or being off-specification.

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Due to the higher level of paraffinic content of VLSFOs over HSFO fuels, it is more likely to see wax precipitation occur with VLSFOs, when subjected to colder temperatures.

The formation of wax crystals during storage and consumption is a potential major source of operational problems with VLSFOs. Therefore, it is vitally important to test for wax appearance (WAT) and wax disappearance temperatures (WDT), as the pour point of the fuel is not a reliable indicator of potential cold-flow issues.

During 2019, VPS developed a proprietary test to be able to measure both WAT and WDT in VLSFOs, which many of our customers have become reliant upon to safeguard their vessels from wax precipitation and it’s potentially damaging consequences.

Current global averages show VLSFO Pour Point is 16°C, whilst the average WAT is 38°C, and the average WDT is 48°C. These figures illustrate why using +10°C above the pour point as an indicator of the cold-flow properties of VLSFO blends is simply insufficient, as well as inappropriate as a risk mitigation measure.

When WAT and WDT results are high, vessels need to consider raising the temperatures of their onboard separators, as well as the temperatures within storage, settling and service tanks.

However, VLSFOs with a short shelf life and high WAT may not be suitable for storing, as heating such fuel accelerates the ageing process and increases the likelihood of fuel sludging.

VLSFOs with low viscosity but high WAT & WDT, need to be heated to ensure a stable flow and to prevent wax formation. Such fuels will likely need to be cooled before entering the main engine, due to their low viscosity. This could present operational issues such as wax formation when the fuel temperature drops below the WAT.

Screenshot 2023 08 21 at 1.48.12 PM

Stability issues relating to VLSFOs have been a concern since their introduction in 2019. To this day we still witness spikes in Total Sediment Potential (TSP) across the world.

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Some VLSFO blends appear stable on bunkering but become unstable over time (within a week or two). Heating the fuel in the tanks (to maintain suitable storage and transfer) and purifiers (to achieve efficient purification) deteriorates the fuel’s stability and fastens the ageing process. 

VLSFOs that are incompatible can cause separator sludging and clogging of filters. As such, numerous vessels have witnessed incompatibility issues when the vessels change from MGO to VLSFO or (vice versa). 

VLSFOs with high WAT/WDT and high cat-fines create a need to operate separators at higher temperatures, at shorter discharge intervals. When this is practice is undertaken, wax starts to form, affecting purifier operation as well as clogging the fuel system’s filters. 

Finally, regarding stability, VLSFOs with high WAT/WDT, that also have chemical contamination, followed by low viscosity, will unlikely to be handled on-board of vessels. In such cases, the only solution is to de-bunker the fuel. 

Between Feb-July 2023, VPS detected contamination in VLSFO fuels in Houston. This contamination saw the presence of two specific isomers of Dicyclopentadiene (DCPD) at concentrations between 1,000ppm-40,000ppm. 

The specific isomers were: 

  • Di-hydro dicyclopentadiene Chemical CAS Number: 4488-57-7 
  • Tetra-hydro dicyclopentadiene Chemical CAS Number: 6004-38-2 

DCPD’s are unsaturated chemical compounds which can polymerise and oxidise under certain conditions. When DCPD polymerises, the fuel begins to exhibit a level of stickiness and becomes more viscous, making it difficult for moving components, eg fuel pump plungers & fuel injector spindles to move freely. These effects cause damage to the fuel injection system. Over a period of time excessive sludge formation is likely to be experienced. 

This specific case saw 12 vessels which bunkered the fuel in Houston suffer major operational issues and damages to auxiliary engines & fuel delivery systems, from fuel supplied by 4 suppliers. The type of problems witnessed were fuel leakage in the ICU (Injection Control Unit) units and fuel pumps not being able to develop the required fuel pressure.

Screenshot 2023 08 21 at 1.48.32 PM

In order to mitigate the risks associated with chemical contamination of VLSFOs, VPS recommend their GCMS-HS Chemical Screening service with each VLSFO bunkering. This service is a pre-burn, rapid, low-cost test, which can identify the presence of volatile chemicals within VLSFOs such as styrene, DCPD and chlorinated hydrocarbons, to name but a few and provide an elevated level of protection to the vessel. 

To summarise, VLSFOs as the most widely used marine fuel powering today’s global fleet, can potentially create numerous operational and compliance issues, due to their varying quality. In order to mitigate the potential risks caused by, poor cold-flow parameters, fuel stability, chemical contamination, low viscosity and sulphur non-compliance, effective fuel management and testing can certainly help reduce and even eliminate such risks.

Related: VPS identifies new bunker fuel contamination at Houston
Related: FOBAS: Possible bunker fuel contamination in Houston and US Gulf area
Related: Viswa Group gives update on bunker fuel issues in Houston
Related: FuelTrust analysis finds fuel content discrepancies in 39% of global bunker deliveries
Related: VPS: Houston contaminated VLSFO bunker fuel was also supplied in Singapore
Related: BREAKING: Vessels supplied in Singapore yet to report engine issues due to contaminated bunkers, following Houston VLSFO case


Photo credit: VPS
Published: 21 August, 2023

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GCMD concludes its final biofuel blend supply chain trial with Hapag-Lloyd

bp provided the B30 biofuel blend to the “TIHAMA”, a 19,870 TEU container vessel operated by Hapag-Lloyd in final trial; marks the end of a series of trials initiated in July 2022.





GCMD concludes its final biofuel blend supply chain trial with Hapag-Lloyd

The Global Centre for Maritime Decarbonisation (GCMD) on Thursday (18 July) said it has successfully completed its final supply chain trial for biofuel blended with very low sulphur fuel oil (VLSFO). 

This marks the end of a series of trials initiated in July 2022 as part of a larger pilot to develop a framework to provide quality, quantity and GHG abatement assurances for drop-in fuels.

In this final trial, bp provided the B30 biofuel blend to the TIHAMA, a 19,870 twenty-foot equivalent unit (TEU) container vessel operated by Hapag-Lloyd.

The biofuel component used is certified to the International Sustainability & Carbon Certification (ISCC) standard – a multistakeholder certification scheme for biobased materials. The biofuel component comprised neat Fatty Acid Methyl Ester (FAME) produced from food waste.

Authentix, a tracer solutions provider, supplied and dosed the FAME with an organic-based tracer at the storage terminal outside the Netherlands. The dosed FAME was then transported to the Port of Rotterdam for blending with VLSFO to achieve a B30 blend, before the blend was bunkered onboard the TIHAMA.

Similar to previous trials, GCMD engaged fuel testing company Veritas Petroleum Services (VPS) to witness the operations at all stages – from biofuel cargo transfer to bunkering. VPS also collected and conducted extensive laboratory tests on samples of the biofuel and biofuel blend collected at pre-determined points along the supply chain to assess quality per Standards EN 14214 and ISO 8217.

With well-to-wake emissions of 13.74 gCO2e/MJ, the neat FAME presented a 85.4% emissions reduction compared to the emissions of the fossil marine fuel. The reduced emissions complies with the MEPC 80, which requires a minimum emissions reduction of 65% in order for biofuels to be classified as sustainable.

GCMD and Hapag-Lloyd determined that consumption of the 4,500 MT B30 blend of FAME and VLSFO resulted in 27.9% emissions reduction compared to sailing on VLSFO.

A newly developed tracer deployed with this supply chain

GCMD collaborated with Authentix to develop and deploy a new organic-based tracer to authenticate the origin and verify the amount of FAME present in the blend. The proprietary tracer blended homogeneously with FAME and was detected at expected concentrations at all sampling points along the supply chain.

This trial marks the first deployment of this tracer in a marine fuel supply chain. Previously, similar tracers were used to authenticate and quantify biofuels in road transport and LPG supply chains.

Development of a comprehensive biofuels assurance framework underway

With the completion of this trial, GCMD has deployed a diverse range of tracer technologies, including synthetic DNA and element-based tracers, in addition to the organic-based tracer used in this trial. The trials have also included the development of a chemical fingerprinting methodology and the evaluation of lock-and-seal and automatic identification systems (AIS) as additional solutions to ensure the integrity of the biofuels supply chain.

Learnings on tracer limitations and benefits will be incorporated into a framework that recommends appropriate use to ensure consistent and robust performance. This effort will complement existing ISCC by providing additional supply chain assurance through physical traceability.

The insights from these trials will be shared in a series of reports covering issues, such as traceability, biofuel degradation, supply chain optimisation and abatement costs. These findings will culminate in a comprehensive assurance framework to provide guidance on biofuels use, slated for release in the fourth quarter of 2024.


Photo credit: Global Centre for Maritime Decarbonisation
Published: 19 July 2024

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MPA, ITOCHU and partners sign MoU on ammonia-fuelled bulk carriers study

As a government agency, MPA,will review and provide their views to the designs of the ammonia-fuelled ships to ensure their safe operations, says ClassNK.





RESIZED venti views

Classification society ClassNK on Thursday (18 July) said it signed a Memorandum of Understanding (MoU) with ITOCHU Corporation, Nihon Shipyard Co., Ltd., and Maritime and Port Authority of Singapore (MPA) regarding a joint study for the design and safety specifications of ammonia-fuelled ships which are under development by ITOCHU and partners.

“The discussion for a specification of ammonia-fuelled ships with a governmental body related to their operation is essential for a social implementation of ammonia-fuelled ships,” ClassNK said. 

“As one of parties of the MoU, MPA, a government agency overseeing the world’s busiest bunkering hub, will review and provide their views to the designs of the ammonia-fuelled ships to ensure their safe operations.”

The MoU is based on the premise that 200,000 deadweight ton class bulk carriers will be built by Nihon Shipyard with an ammonia dual-fuelled engine.

“The necessary clarifications of the specification for the ammonia-fueled ship to carry out ammonia bunkering in Singapore will be conducted among parties of this MoU, for the commercialisation of ammonia-fuelled ships,” ClassNK added.


Photo credit: Venti Views on Unsplash
Published: 19 July 2024

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“K” Line to use biofuel on three Gram Car Carriers-chartered vessels in Singapore

Biofuel will be supplied to the sister vessels “Viking Ocean”, “Viking Diamond” and “Viking Coral” while bunkering in Singapore, says Gram Car Carriers.





“K” Line to use biofuel on three Gram Car Carriers-chartered vessels in Singapore

Norwegian transportation firm Gram Car Carriers (GCC) on Thursday (18 July) said Kawasaki Kisen Kaisha (“K” LINE) will use biofuel on three vessels chartered from GCC from July onwards. 

“The biofuel will be supplied to the sister vessels Viking Ocean, Viking Diamond and Viking Coral while bunkering in Singapore, an Asian hub for marine biofuels,” GCC said on its social media. 

“The use of biofuel is a key environmental initiative to reduce emissions across the entire value chain (well-to-exhaust) and an effective way of transitioning to low-carbon marine fuels amid globally tightening environmental regulations.”

“We support the green mobility shift. This means that GCC commit to supporting the transition of both vehicles and their logistic chain towards a zero-emission future in close cooperation with leading customers such as K-Line,” said Georg A. Whist, CEO of GCC.


Photo credit: Gram Car Carriers
Published: 19 July 2024

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