• Follow Us On Our Preferred Social Media Platform:

CTI-Maritec, Innospec experts address VLSFO WAT/WDT, stability, ‘snake oil’ additives at January webinar

27 Jan 2022

The VLSFO Trends, Issues & Best Practices webinar jointly organised by CTI-Maritec, Innospec and its Hong Kong representative Hostmost took place on Wednesday (19 January).

Moderated by Manifold Times, the event saw Bharath Kumar, Technical Manager at CTI-Maritec, and Martin Chew, Marine Regional Sales Manager Asia Pacific at Innospec, respectively sharing their industry expertise on bunker fuel testing and marine fuel treatment chemicals.

The speakers spent a third of the session taking questions from the audience; several noteworthy queries and a summary of their answers are as follows:

Queries to CTI-Maritec

Q: What can one do when encountering a high WAT/WDT bunker fuel and/or unstable product; especially when it is impossible for a vessel to heat up its bunker fuel storage tanks to 70°C?

A: Firstly, we need to identify if the fuel is truly unstable and the resultant issues that are occurring is due to asphaltene sludge dropping out of the mix or due to the formation of wax in the fuel oil system.

This may be determined by identifying a careful balance in the operational temperatures throughout the fuel oil system based on the fact that an unstable fuel will worsen, and a waxy fuel may improve with increase in temperature.

Testing the fuel for both potential instability and wax formation temperatures can reduce the effort spent in guessing the correct storage and purification temperatures.

In the unfortunate case where the fuel is truly unstable, it should be noted identifying the correct Wax Appearance Temperature (WAT) may not be possible due to the limitations of the test methods.

Where it has been identified the Wax Disappearance Temperature (WDT) is impossible to achieve onboard in the vessel’s storage tanks, pre-emptively keeping the temperatures above the identified WAT may be the best action to do to avoid a more problematic situation.

Q: I have VLSFO that will be kept in storage for a long period due to the vessel transiting in and out of an ECA for more than two months. What can I do to ensure my fuel is stable during this period?

A: We advise the vessel operator to take a pre-emptive approach towards the issue. The stability and wax formation tendencies of the fuel will need to be identified to ensure the fuel is capable of being stored for the intended period without unduly breaking down and causing sludge/ wax formation in the tanks.

The above in conjunction with the best practices of ensuring a low ROB prior to bunkering, pre-emptively dosing the tanks with a suitable stability improver, and preventing any commingling of fuels in storage, can improve the operational reliability of the fuel kept in storage.

Queries to Innospec

Q: Why do some people say bunker fuel additives are associated with “snake oil”?

A: It is not easy to understand the science and testing that goes behind the creation of a marine fuel additive formula.

There is much technology, including research and development, that goes into manufacturing fuel treatment chemicals that evolves with the latest changes in marine fuel quality (i.e. IMO 2020); and most of these technologies have been patented by Innospec.

However, even the best technology will not have 100% efficacy such as our Covid-19 vaccines today. This is where the association with “snake oil” comes about.

A tip is to look for specialists directly from the fuel additive industry as we are dealing with marine fuel itself, rather than shipping firms reselling fuel chemicals as part of their “one stop service” service portfolio.

Q: If the marine fuel testing report shows everything is on spec, should we still treat it with chemicals? What can you do if you get on spec fuel but still face issues?

A: ISO 8217:2017 parameters are a good guide for determining an on spec marine fuel. However, it does not give a guaranteed “all clear” during the duration of fuel usage and this is something we have all experienced even more so with Very Low Sulphur Fuel Oil (VLSFO).

This development is due to weakness of the standards. So yes, even on spec fuels should be treated as “prevention is better than cure” as there are also issues such as fuel aging – a non-reversible process.

Q: Is Total Sediment Potential (TSP) a useful indicator to understand the stability of the fuel?

A: No, from our experience TSP produces less than 50% accuracy.

Further, not any chemical additive will be able to reduce TSP unless it has technology to break up the sediment to pass through the filter. Sediments are not just limited to asphaltenes but other contaminants including iron, rust, sand and etc.

We believe a product that can address TSP should be introduced upstream by the bunker supplier so shipowners can receive on spec marine fuels. Ideally, the only time vessels will need an additive to improve TSP is during prolonged storage when TSP is expected to increase over time.

Related: Innospec Fuel Specialties and Maritec presents: VLSFO Trends, Issues & Best Practices webinar


Published: 27 January, 2022

Related News

Featured News

Our Industry Partners

  • argus

PR Newswire