Effectiveness of Vapor Corrosion Inhibitors Under Elevated Chloride Conditions for Aboveground Storage Tank Application

Conference · Wed Jan 24 04:00:00 EST 2024

OSTI ID:2322415

Shukla, Pavan K. ^[1]; Fuentes, Roderick E. ^[1]; Nordquist, Andrew ^[1]; Wiersma, Bruce J. ^[1]; Pederson, Ingrid ^[2]

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1. Savannah River National Laboratory (SRNL), Aiken, SC (United States)
2. Enbridge Centre, 10175 101 Street NW Edmonton T5J 0H3 Canada

The sand quality used to construct the tank pad is an important contributing factor to the rate of corrosion that occurs on the soil-side of the aboveground storage tanks (ASTs) floor plates. Clean sand that meets specific criteria provides the first line of defense for mitigation of tank floor corrosion. However, it has been observed that the sand quality used for some existing tanks differ greatly from the specifications provided in the API 651 standard; this could be partially due to initial sand quality not meeting the specification, and partially due to the environmental effects over time. For example, rain-water intrusion could lead to higher than the specified contents of corrosive species such as chloride. Tank operators are increasingly using vapor corrosion inhibitors (VCIs) either as a stand alone or in combination with cathodic protection (CP) for ASTs to mitigate soil-side corrosion. VCIs are delivered either through-thefloor or injected through the ports in the ring wall. Experimental studies were conducted to evaluate VCIs’ performance at elevated chloride concentrations and to study the effectiveness of the delivery methods under extreme chloride conditions. The experimental work found that VCI performance is robust and not compromised due to high chloride levels, such as 300 ppm or more. The work also showed that the through-the-floor VCI delivery method is more beneficial compared to the through-the-sand-pad method when tank pad corrosivity is elevated.

• Research Organization: Savannah River National Laboratory (SRNL), Aiken, SC (United States)
• Sponsoring Organization: USDOE Office of Environmental Management (EM)
• DOE Contract Number: 89303321CEM000080
• OSTI ID: 2322415
• Report Number(s): SRNL-STI-2024-00033
• Country of Publication: United States
• Language: English