Study Finds the Source of Fuel System Corrosion
Since 2007, there has been an increase in the amount of reports being received for unusually severe and accelerated corrosion of metal parts associated with storage tanks and equipment for Ultra Low Sulfur Diesel (ULSD). A 2012 study conducted by the Battele Memorial Institute on the Corrosion in Systems Storing and Dispensing Ultra Low Sulfur Diesel (ULSD) has concluded that the main cause of corrosion is linked to a specific strain of bacteria that releases acetic acid.
Acetobacter Linked to Fuel Tank Corrosion
The study found that the dominant organism identified in the study, Acetobacter, has characteristics that led them to believe it was the cause of the corrosion observed in all of the sites. These characteristics included acetic acid production, ethanol utilization, low pH requirements, and oxygen. Although geographically on opposite sides of the country, from different fuel suppliers, and of relatively new construction materials, the presence of the organisms was relatively uniform across all of the findings.
Aggressive Chemical Species Hypothesis Evalution
One of the three hypotheses studied investigated which chemical species were capable of facilitating corrosion (See below.)
The Final Hypothesis
The project’s final hypothesis for the study was as follows: “Corrosion in systems storing and dispensing ULSD is likely due to the dispersal of acetic acid throughout USTs. It is likely produced by Acetobacter bacteria feeding on low levels of ethanol contamination. Dispersed into the humid vapor space by the higher vapor pressure (0.5 psi compared to 0.1 psi for ULSD) and by disturbances during fuel deliveries, acetic acid is deposited throughout the system. This results in a cycle of wetting and drying of the equipment concentrating the acetic acid on the metallic equipment and corroding it quite severely and rapidly.”
Core Engineered Solutions has the experience and offers a range of solutions for corroded tanks and equipment as well as methods to prevent future corrosion. For questions or a quote please contact Core today firstname.lastname@example.org.