Ship engine lubricants to evolve with bunker fuel alternatives

Ship engine lubricants will have to evolve along with the changing bunker fuel market as more stringent emission controls come into play, said Total Lubmarine Technical Director Jean-Philippe Roman in an interview with Platts at the Sea Asia 2013 show in Singapore.
With the evolving regulations on ship emissions by the various Emission Control Areas (ECA) as well as the International Maritime Organization’s global sulfur cap limits becoming more stringent in 2015-2020, shipowners have to start considering alternative fuels other than heavy fuel oil, to power their ships.
The current focus is on alternatives such as distillates and LNG to comply with stricter global sulfur regulations. Lubricants for these same ship engines will have to evolve along with the type of marine fuel used, Roman said.
For existing conventional diesel engines that currently run on heavy fuel oil, most ships use two types of lubricants to ensure engines run smoothly, and the combination of the two is usually “double trouble,” according to Total Marketing and Analysis Manager Serge Dal Farra.
If there were a mismatch in both types of lubricants, it would result in severe engine damage, said Dal Farra.
The problem usually occurs when the basicity of the lubricant is high and the sulfur level in the marine fuel is too low. This could mean more calcium carbonate deposits in the ship’s engine, potentially causing severe damage, Roman said.
The level of basicity usually determines how well the lubricant can break down the acid that makes up the sulfur in marine fuels.
With marine fuels expected to contain less sulfur, the type of lubricant used would need to change at the same time, especially with some ECAs now mandating a maximum of 1% sulfur, he added.
Ship engines designed to use LNG as bunker fuel cannot use the same type of lubricants used in conventional engines that run on heavy fuel oil as these contain calcium carbonates, Roman stated.
Total is also working on coming up with a next generation single cylinder oil lubricant, which would reduce some of the problems in a two-type lubricant mix and is aiming to launch it sometime in 2015, Roman said.
Roman expects that most ships will still use heavy fuel oil, with a significant level of distillate use in ECA zones.
The reality of LNG as marine fuel is still a ways away, with the global supply infrastructure not fully in place, and while the price of LNG looks attractive now, it might not necessarily be the case in the future, Roman said.
(April 9, 2013)