The world’s largest single-skin LPG tanks are located at the Sullom Voe Terminal in the Shetland Islands. Each tank has a 22,000t capacity, they are 48m in diameter and were erected in the 1970s. The tank sat on a concrete ring foundation. These had been subject to the full environmental effect of an exposed maritime climate over the years as well as the cyclical loading as the tank was operated.

The product was kept at -48 C and whilst a base heating system was in place to stop the ground freezing it was known to have failed in part and ice could be seen Due to the life extension given to the terminal in 2000, a management review by the operators of the terminal had determined that an inspection of the concrete structure and the tank foundation would be a worthwhile exercise. Given our initial involvement with the base heating system, we were also tasked with the client’s Consulting Engineer to undertake this inspection.

Please download this case study for more information on the replacement of base heating tanks on single-skin LPG tanks.