What are Single, Double and Full Containment Storage Tanks?

[m.boka]

Hello
Recently I've been responsible for design storage tanks which were remarked as single, double and containment ?
To frank speaking, I haven't faced with these kind of Storage tanks
Do you have any experience about these kind of Storage tank ?
What about Design method and considerations?

[aaronss]

Single containment tanks are the basic LNG storage units with a single wall and steel roof only.
Double containment tanks have a metal inner and a pre-stressed outer layer usually with an infill between layers.
A full containment tank has concrete outer wall and roof thus rated for higher T but lower P and will have vapor integrity.
D/F containment tanks cost about one and a half more, but allow closer spacing, especially in the case of the F containment types.