VPS Urges Vigilance When Using "Hybrid" ECA Fuels

VPS' Georgios Sigalas says hybrid bunkers can provide significant benefits if "challenges are understood and can be addressed."

Veritas Petroleum Services (VPS) Wednesday urged ship operators to be "very vigilant" when using so-called "hybrid" bunkers designed for Emission Control Area (ECA) compliance, but that such bunkers can provide significant benefits if "challenges are understood and can be addressed."

VPS' Georgios Sigalas says the hybrid bunkers, also known as heavy-distillates or ultra-low sulfur fuel oil (ULSFO), are "essentially marine diesel fuels, blended diesel fuels and low viscosity residual fuels," which have been known to the marine market for many years.

Such fuels were said to be very paraffinic with virtually no aromatics, meaning very good to excellent ignition and combustion properties, while their high viscosity relative to ISO spec distiallte fuels reduces the chance of fuel pump leakage and damage issues.

"The downside of these new ECA fuels is that they do not comfortably fit into the current ISO 8217 marine fuel specifications forcing the fuel buyer to compromise in the selection of the most suitable specification for ordering and comparison," says Sigalas.

One such downside is the very aliphatic nature of some of the fuels, which can create "potentially serious handling issues" when in contact with fuels containing cracked residues.

"Vessels that trade in and out of ECAs would have to manage the changeover process very carefully," says Sigalas.

Further, VPS explains that some of the fuels are based on low viscosity residual blends and blended using cracked distillates, meaning they have an increased likelihood of high levels of cat fines (Al+Si).

"Hence, on-board treatment must be maintained at its highest efficiency," advised Sigalas.

As Ship & Bunker has previously reported, the more challenging cold flow properties of some of the new products can also pose risks, and VPS notes that many of these fuels have already been treated with cold flow improvers that mean onboard treatments are unlikely to render further improvements.

"Ship operators must be very vigilant about the use of these fuels by testing deliveries routinely and monitoring supplier performance," said Sigalas.

"Attention should be given to their quality and availability trends. Compatibility test with other products onboard vessel must be also included."

In addition to advising that vessel crew members should be trained on the fuels' use, as well as onboard fuel performance monitoring procedures, Sigalas says mixing ECA fuels with other fuel types, including MGO, should be avoided.

Last year, Steve Bee, who as Ship & Bunker previously reported will be joining VPS later this year, said the new "hybrid" fuels appear to burn faster and cleaner than their traditional fuel oil counterparts.