BUNKER ALERTS: High potassium fuels in Honolulu, Hawaii

In DNVPS’ ongoing research, it has been found that the Ash and Elements contents of bunkers in some cases do not correlate, indicating the presence of elements not usually present in marine fuels.

In this regard, DNVPS has observed that a high percentage of fuels ex. Honolulu contain Potassium at levels as high as 186 mg/kg and averaging 90 mg/kg. Even at the maximum level detected, these fuels meet the ISO 8217 specifications for Ash, mainly because of the low levels of other elements.

DNVPS believes the high Potassium content arises from the use of certain additives to control the Hydrogen Sulphide levels in crudes. Normally, the additives utilised in these instances are Sodium-based alkalis, but there is good reason to believe that Potassium hydroxide has been used in the "sweetening" process to reduce the Hydrogen Sulphide in the Honolulu fuels.

DNVPS studies suggest a strong link between bunkers with high Potassium levels and corrosion of turbo charger nozzle rings as well as increased ash deposits in the post-combustion areas, including turbo chargers.