A significant number of ships have experienced serious operational problems, such as chiefly sticking/seizing fuel pumps and in some cases filter blockages, after lifting bunker fuels from the US Gulf region since late March and during April-May. Commenting on the situation, IBIA said that these fuels possibly contravene MARPOL Annex VI.
Most cases have reportedly been caused by intermediate fuel oils (IFOs) bunkered in the Houston area, though there are indications that similar problems have been caused by fuels bunkered in Panama, IBIA noted.
At this stage, there are differing views as to the root cause of this problem and how to mitigate the various risks. Several fuel testing agencies have reported that the fuels met ISO 8217 specifications during routine testing against the standard. It was only when vessels began encountering problems they began forensic-level investigative fuel analysis.
Reports from testing agencies have identified certain commonalities between these fuels indicating they contain chemical contaminants from non-petroleum sources, IBIA said. Most findings include phenols and Tall Oil, but the reports from testing agencies are not conclusive and their investigations are continuing.
It seems almost certain, however, that the fuels contravene Clause 5 in ISO 8217 and Regulation 18.3 of MARPOL Annex VI which broadly state that fuels shall not contain any material in a concentration that adversely affects the performance of machinery.
Quality issues are not new in the industry, with shipowners reporting such cases around the world over the past 30 years. Usually, the origin of problem fuels has been limited to a specific geographic area.
Unfortunately, the nature of the contamination can often be so obscure that no amount of routine analysis will make the defect apparent until the fuel proves defective in use and the subsequent detailed forensic examination identifies the cause. In many of these episodes, the source of the contaminant is never adequately identified, but in summary, the root cause was a lack of control of the quality of cutter stock used in the marine pool.
To improve control and prevent such cases, IBIA draws attention to its ‘Best practice guidance for suppliers for assuring the quality of bunkers delivered to ships‘ guide, especially the recommendation in Chapter 4, in particular 4.2 – Quality control during production of bunkers and 4.3 – Quality control in the supply chain.
