One results of bunker gasoline contamination: a seized gasoline pump plunger. [Photo: VPS]
Leading gasoline testing companies supplier VPS reviews that the bunker gasoline contamination subject in Houston that it recognized in July has unfold. At that point, VPS knowledgeable its prospects and the broader market, of the presence of Dicyclopentadiene (DCPD) isomers at considerably excessive ranges inside VLSFO bunker gasoline deliveries in Houston.
Four weeks later, says VPS, it may present an additional replace on the unfold of this gasoline contamination subject: Fourteen vessels in complete, have now acquired this contaminated gasoline and suffered some type of injury to their auxiliary engines and gasoline supply techniques. Twelve of the vessels acquired their gasoline in Houston, whereas an additional two vessels acquired their gasoline in Singapore, with the gasoline being delivered by 4 suppliers.
This is just not the primary time that bunker gasoline contamination first found in Houston has later been present in gasoline bunkered elsewhere.
VPS detected the bunker gasoline contaminants utilizing its in-house GC-MS (fuel chromatography – mass spectrometer) analytical methodologies,n choice to the ASTM D7845, Standard Test Method for Determination of Chemical Species in Marine Fuel Oil by GCMS. The VPS methodology is able to detecting and measuring the DCPD and its isomers, whereas the ASTM D7845 methodology is restricted to detecting solely 29 chemical contaminants, which don’t embrace DCPD species.
Initially, VPS reported that eleven vessels had suffered operational points, comparable to lack of energy and propulsion whereas at sea. These results resulted from gasoline leakage within the ICU (injection management unit) items and gasoline pumps not with the ability to develop the required gasoline stress, affecting solely the auxilary engines and never major engines. The contaminated VLSFO had been delivered in Houston, by one single gasoline provider.
The particular contaminants are: Di-hydro dicyclopentadiene Chemical CAS Number: 448-57-7 Tetra-hydro dicyclopentadiene Chemical CAS Number: 6004-38-2
DCPDs are unsaturated chemical compounds that may polymerize and oxidize underneath sure circumstances. However, the speed of this polymerization course of will be diminished by the presence of inhibitors which can be usually discovered inside gasoline oil.
Should these compounds begin polymerizing, the gasoline begins to exhibit a stage of stickiness and turn into extra viscous, making it tough for shifting elements, comparable to gasoline pump plungers and the gasoline injector spindles to maneuver freely. These results trigger injury to the gasoline injection system. Over a time frame extreme sludge formation is prone to be skilled.
The DCPD compounds that have been detected on this gasoline ranged from 3,000 to 7,000 ppm (0.3-0.7%) per supply.
In complete, the quantity of contaminated gasoline delivered to the 32 vessels, was 61,494 metric tonnes.
Three vessels de-bunkered the contaminated gasoline previous to burning, following a “Caution” outcome from the VPS Chemical Screening service, highlighting the worth of this pre-burn service.
An additional three vessels de-bunkered the gasoline after struggling preliminary engine injury from burning the gasoline. Another two vessels burned the gasoline of their major engines with out subject after switching it from their auxiliary engines, the place it had brought on operational injury.
