Storage Tank - Tank Failures

Tank Failures

There have been numerous catastrophic failures of storage tanks, one of the most notorious being that which occurred at Boston Massachusetts USA on January 14, 1919. The large tank had only been filled eight times when it failed, and resulting wave of molasses killed 21 people in the vicinity. The Boston molasses disaster was caused by poor design and construction, with a wall too thin to bear repeated loads from the contents. The tank had not been tested before use by filling with water, and was also poorly riveted. The owner of the tank, United States Industrial Alcohol Company, paid out $300,000 (worth a lot more back then) in compensation to the victims or their relatives.

There have been many other accidents caused by tanks since then, often caused by faulty welding or by sub-standard steel. However, storage tanks also present another problem, surprisingly, when empty. If they have been used to hold oil or oil products such as gasoline, the atmosphere in the tanks may be highly explosive as the space fills with hydrocarbons. If new welding operations are started, then sparks can easily ignite the contents, with disastrous results for the welders. The problem is similar to that of empty bunkers on tanker ships, which are now required to use an inert gas blanket to prevent explosive atmospheres building up from residues.