Oil & Gas Journal - April 03, 2017

Ahmed Saad Noaman

Petrojet Cairo

External floating single-roof tanks should not be used to store gasoline in hot regions unless the deck plate’s thickness exceeds 10 mm and it has been treated with an anti-corrosion coating. Solar radiation can cause large problems in storage tanks with floating roofs. The direct contact between the fluid and the floating deck raises the fluid’s temperature and increases the vaporization rate of products inside the tank, both wasting product which could otherwise be sold and creating an unsafe operating environment.

This article centers on a study performed to determine the effects of July 31, 2016, solar radiation on a gasoline storage tank in Cairo, Egypt. Late July is typically the hottest time of the year in Cairo, 40° C. with 20 mph winds. The study was repeated and analyzed under corrosion conditions to determine corrosion’s effect on fluid temperature.

The study used computational fluid dynamics (CFD) analysis to measure the gasoline’s temperature for 1 hr and then calculate vapor losses by the charts provided in Perry’s Chemical Engineering Handbook. 1 Simulating solar radiation’s effect on fluid temperature inside the tank during design will increase the tank’s safety during operation.

Previous studies focused on if thermal stress on the floating roof could

Study sets design limits on floating single-roof tanks

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