Current Design Considerations
Publication Date: 2012-Jul-18
The IP.com Prior Art Database
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A REVIEW OF CURRENT DESIGN CONSIDERATIONS
THE 9TH INTERNATIONAL LNG/LPG CONFERENCE
PARIS - OCT 5-8 1982
C. COLLINS & W.M. VENTHAM M.W. KELLOGG LTD., LONDON
D.B. CRAWFORD & S.E. HANDMAN M.W. KELLOGG, HOUSTON
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The storage of liquid natural gas has now become accepted worldwide as an efficien~ means of providing a concentrated source of e~ergy.
Design ,requirements have become more stringent in recent years due to political pressures and the need to improve the safety of these
installations as more operating experience is obtained.
This paper is intended to present an overview of current design
considerations for large LNG storage systems associated with base load LNG plants and LNG receiving terminals.
2.0 STORAGE TANKS
Development of LNG storage tank designs has been influenced by recent experience with incidents associated with liquid hydrocarbon storage tanks; for example, the Qatar LPG tank failure and the Staten Island LNG tank a~cident. Economic considerations, whilst important are still strongly affected by safety considerations. Political and logistic aspects will also affect the selection of a tank syst~ for any particular installation. These points have generally resulted in increased conservatism and hence increased capital investment for LNG storage systems.
2.2 Alternate tank, designs
The following briefly describes the main }ypes of tank which have been used for LNG storage. (See also Ref. 1, 2, 3).
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Cylindrical Above Ground Tanks
double wall cylindrical metallic tank with bund. Inner tank capable of containing LNG. Outer wall (carbon steel) for containing the tank insulation and as a vapOur barrier. External low bund wall for containing liquid in the event of leaks.
double wall cylindrical metallic tank surrounded by concrete wall. As above, but with a protecting concrete wall capable of holding tank contents in event of failure of inner tank and outer carbon steel wall.
double wall cylindrical tank with metallic inner container suitable for LNG and concrete outer shell. Concrete outer wall suitable for containing LNG in the event of failure of metallic inner tank.
double wall cylindrical concrete tank. Both inner and outer walls are constructed in concrete. Both walls have carbon steel liners to act as vapour barriers.
single wall cy!indri'cal concrete tank with metal membrane. The inside of the concrete wall is lined with a layer of rigid
insulation. A metallic membrane which acts as the LNG container is fitted to the insulating layer.
Small spherical single wall LNG storage tanks have been used on peak shaving installations and for LNG storage on-board ships. Larger spherical tank designs have recently been proposed for base load LNG plants (Ref. 4).
A number of buried concrete tanks with the tank roof located at grade have been built in Japan. A few tanks have been built at ground level surrounded by a full...