The average person probably does not give much thought to natural gas, petroleum or water, but these three substances are all around us. Natural gas fuels our stoves and heats our water. Petroleum provides diesel fuel for big rigs that bring food to our grocery stores. Meanwhile, gasoline powers our cars and jet fuel makes air travel possible. Water, of course, is one of life’s basic necessities.
A complex infrastructure brings gas, petroleum and water from deep within the ground to our homes. As these products are processed and transported, they need to be stored. Aboveground storage tanks and cryogenic storage tanks are the two most common types of large scale storage. These tanks provide safe, efficient storage for the substances we’ve mentioned above, as well as many other chemicals.
Aboveground Storage Tanks (AST)
Aboveground Storage Tanks (ASTs) are cylindrical structures with a fixed or floating roof. Designs vary widely. Some ASTs actually have two roofs: an inner floating roof designed to help prevent emissions and an outer geodesic dome to provide structural integrity. Strict industry standards and regulations guide many aspects of storage tank design and maintenance. Stored product, operating environment and cycle frequency must all be considered when engineering and selecting materials for your storage tank.
Many gases, such as natural gas, ethane, oxygen and nitrogen are stored in a liquid state. Low-temperature or cryogenic storage tanks allow for easy access and greater control of the extraction process. In their
liquid state, gases are compressed and can be stored in a much smaller storage tank. The most important characteristic of a cryogenic storage tank is the ability to store product at very low temperatures. Liquefied natural gas is stored at -260 °F (-162 °C). Tanks can be designed in a wide range of sizes, depending on operational needs. Most cryogenic storage tanks are full containment tanks. Auto-refrigeration is used to maintain the appropriate pressure and temperature within the tank.
The next time you take a hot shower, drive to the movies or drink a cold glass of water, you can thank a storage tank. All of these products have likely spent some time in a storage tank before they reached you. These feats of engineering make so many of our modern conveniences possible.