Above-Ground Storage Tanks in the Houston Ship Channel
A typical above-ground storage tank.Copyright 2008 Gnangarra, Wikipedia http://en.wikipedia.org/wiki/File:Fuel_tank_gnangarra.jpg
Students are provided with an introduction to above-ground storage tanks, specifically how and why they are used in the Houston Ship Channel. The introduction includes many photographic examples of petrochemical tank failures during major storms and describes the consequences in environmental pollution and costs to disrupted businesses and lives, as well as the lack of safety codes and provisions to better secure the tanks in coastal regions regularly visited by hurricanes. Students learn how the concepts of Archimedes' principle and Pascal's law act out in the form of the uplifting and buckling seen in the damaged and destroyed tanks, which sets the stage for the real-world engineering challenge presented in the associated activity, Above-Ground Storage Tank Design Project —to design new and/or improved storage tanks that can survive storm conditions.
The Houston Ship Channel ships more goods internationally than any other U.S. port, and 75% of those goods are petrochemicals. The 50-mile-long Houston Ship Channel runs from near downtown Houston to the Gulf of Mexico and is home to ~300 industrial facilities and~4,200 above-ground storage tanks, which contain more explosive materials, toxic gases and deadly petrochemicals than anywhere else in the country. The storage tanks are of high concern because they can uplift during flood events, displacing and crashing into nearby objects, and buckle from wind, waves and moving debris. In the event of major storms and hurricanes, the resulting damage to the region and national economy could be catastrophic in terms of facility shut-downs and environmental impacts. Code instruction manuals lack provisions for shell buckling or uplift due to flooding.
After this lesson, students are expected to:
- Describe above-ground storage tanks.
- List where and why above-ground storage tanks are used and the associated environmental issues.
- List and explain the different types of failure associated with above-ground storage tanks.
- Use engineering terminology to explain how Pascal's law and Archimedes' principle relate to the use of above-ground storage tanks.