IMO2020: Managing the Risk of Commingling VLSFO Bunkers

by Michael Donaldson-Badger, Managing Director - DMCC, NSI
Wednesday November 27, 2019

Compatibility (the stability of a fuel mixture) remains the biggest concern for everyone in the market but managing this risk does not have to be complex or expensive.

The probability of two VLSFO fuels being incompatible remains low, however the consequences associated with such an incident can be extreme and under most sets of suppliers and traders terms and conditions the buyer/ owner would be left bearing the liability.

There are five methods across the market for determining the compatibility of fuels detailed in the table below, The first two being the most well known and accurate options. The S-Value, P-Value and P ratio tests when used without mixing do not yet have the confidence of all testing agencies in the bunker market - it should be noted that the output result is merely a 'prediction'. We all appreciate that pre-delivery advised COQ's can differ from the analysis of the oil delivered for many reasons and it seems foolhardy to me that we would base comingling decisions based on these 'prediction' tests when there are much better alternatives. It is also to be noted that those marketing this testing and risk assurance are so far are not prepared to back this up by underwriting any liability associated with the risk.

So what's the simple alternative?

At NSI we are working with our customers first and foremost to actually avoid having to comingle – helping buyers with maximum operational flexibility possible and providing   and complete planning data to make the most informed decisions possible. We all appreciate that in almost every terms and conditions that quality claims are barred if fuel has been co-mingled, so surely it is prudent to avoid co-mingling as much as possible. Where the ships fuel tank configuration just doesn't allow the flexibility required as a first instance we recommend blending the known quality fuels that are already onboard. The key for us in helping owners avoid issues with co-mingling has been the implementation of compatibility matrixes.

To achieve the lowest risk in comingling,  the method to give highest level of confidence remains to mix the two or more fuels at the comingling ratio and perform the total sediment tests. With a few minor operational changes it has been possible for our customers to reduce the frequency of occasions where it is required to comingle new fuels. We have worked with a several owners to alter their fuel testing program regime and with each new bunkering they now submit an additional small sample (50mls – about the same size of a urine sample you may give to the doctor) with this sample your testing program will produce a compatibility matrix of your fuels onboard. In addition to this  by sending an additional  small sample for retention which may forwarded to the next bunkering port, It is possible  to facilitate the testing  of existing fuels with proposed new fuels  prior to the vessels arrival the typical cost for this testing being around $150 USD.

Example compatibility matrix for a vessel with 4 storage tanks with one dedicated to LSGO.

Guarding against compatibility risk does not have to be complex or expensive, with good planning and a little foresight many load on top situations can be avoided. Those that cannot be avoided using tools like a compatibility matrix can quickly and in a cost effective way make all stake holders aware of the operational flexibility and limitations of the vessel in question. In some cases a good compatibility matrix actually helps owners to be able to safely co-mingle prior to the next bunkering and free up the optimum sized tanks.

For more information on how to mitigate your risk in a cost effective way using tried, tested and reliable methods please get in touch.