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Picture for The Irony of Creating a Lining Failure in the Process of Inspection
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The Irony of Creating a Lining Failure in the Process of Inspection

Product Number: 51324-21128-SG
Author: Steve Liebhart
Publication Date: 2024
$40.00
Inspection and shipping schedules often require hydrocarbon storage tanks and rail cars to be removed from service and turned around quickly. This can be for lining/tank inspection or to clean and repurpose it, among other reasons. For whatever reason needed the tank is drained, and any remaining material, including all vapors, must be removed for safe entry into the tank. This process might involve forced heat and ventilation but is not often precisely controlled and even less often are details of the process documented. After cargo is evacuated from the tank the hope is to find the lining intact, and then return it to service as soon as possible. During the process of evacuating volatile material from the tank it is important to handle the lining with care and attention so not to allow the empty tank shell and lining to heat up too fast. This is a dangerous scenario for the well-being of the lining if heated too fast while it contains volatile materials absorbed in the film. When a lining saturated with volatile hydrocarbon is rapidly subjected to increased temperature an equally rapid increase in vapor pressure occurs as the material changes from liquid to gas. Damage to the lining can occur if the vapors can’t escape before generating enough pressure to form blisters and/or cracks. This paper/presentation will discuss the physical phenomenon occurring during the heating and desorption of gasoline from a lining recently removed from immersion service, and how inadvertently damaging the lining during this sensitive process can occur. The purpose of this work is to raise awareness of this phenomenon and show how the long-term performance of a lining can be dramatically impacted in a matter of minutes if not appropriately cared for. Some guidance on how to avoid this problem will also be discussed.