Contaminated VLSFO in Houston Was Also Supplied in Singapore

by Ship & Bunker News Team
Monday August 7, 2023

Testing and decarbonisation advisory services firm VPS has issued an update on its findings around the recent Houston VLSFO contamination, revealing that the product in question has also been supplied in Singapore.

VPS first announced it had found the contamination on July 10, saying the presence of dicyclopentadiene had been detected in significant quantities in VLSFO deliveries at Houston.

At the time, 11 vessels were identified as having suffered operational issues, including loss of power and propulsion at sea, and the contaminated product was thought to have been delivered by a single supplier.

The firm has now identified a total of 14 vessels damaged by the fuel, with the product being delivered by four suppliers, it said in an emailed statement on Monday Twelve of these vessels received the fuel at Houston, and the remaining two in Singapore.

Beyond that, 18 other vessels that received the fuel either reported no damage or provided no feedback. Three of the vessels had debunkered the fuel before using it on a precautionary basis.

These 18 additional vessels were bunkered by 13 additional suppliers, taking the total number of suppliers with the contaminated product to 17 companies. A total of 61,494 mt of deliveries of the contaminated fuel have been identified.

The specific contaminants identified are di-hydro dicyclopentadiene (chemical CAS number 448-57-7) and tettra-hydro dicyclopentadiene (chemical CAS number 6004-38-2).

"DCPDs are unsaturated chemical compounds which can polymerise and oxidise under certain conditions," VPS said in the statement.

"However, the rate of this polymerisation process can be reduced by the presence of inhibitors that are typically found within fuel oil.

"Should these compounds start polymerising, the fuel begins to exhibit a level of stickiness and become more viscous, making it difficult for moving components, such as fuel pump plungers and the fuel injector spindles to move freely.

"These effects cause damage to the fuel injection system.

"Over a period of time excessive sludge formation is likely to be experienced."