Storage Tanks
Storage tanks & containment type
During the process in each unit as well as in the Refinery
as a whole there is a need to store some of the produced materials either as a
Final Product or to be further processes or blended.
There are different Spherical and Cylindrical Storage tanks sometimes
working at temperatures down to -190 DegC.
Storage tanks are highly critical components of an LNG
plant. LNG tanks can be categorized from di.erent aspects:
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Fix or on carrier tanks
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Containment type
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Above ground, in-ground
types & underground
Fixed storage tanks are normally made with 4 main
containment types:
• Single containment: This tank has an inner tank made of 9
% nickel and an outer tank made carbon steel. In case of leakage there is no protection
other than having a large construction free area. For this reason this type of
tank is not used for a long time.
• Double containment: This type has a secondary containment
steel or concrete dike wall close to the vapor containing the outer tank.
• Full containment: This type has a 9 % inner tank and a
concrete outer tank which allows leakage to exit only from the roof. This is
the most constructed LNG tank type and requires much less land.
• Membrane type: This type – which is mainly an in-ground or
underground type – uses a membrane cladding of stainless steel on the
insulation and a concrete outer tank. The construction cost of this type is
high – as such this design is applied when very limited land is available.