Det Norske Veritas - Germanischer Lloyd

CONCRETE LNG TERMINAL STRUCTURES AND CONTAINMENT SYSTEMS
 N DNV-OS-C503

Annotation

Scope and applications

The standard is applicable to LNG Export and Import Terminal Structures using concrete as the structural material in the support structure as defined in 302 and 303 below.

LNG Export Terminal Structures

LNG export terminals are, by nature, located near the coast and are designed to liquefy the natural gas which will then be loaded onto LNG carriers. An LNG export terminal generally includes:

— an incoming natural gas metering and receiving station, including in the case of a two phase incoming pipeline, a slug catcher

— condensate stabilisation and storage

— gas treatment units in which any acid gases, water, heavier hydrocarbons and, if appropriate, mercury which might be present in the incoming gas are extracted

— liquefaction units which produce LNG and within which, ethane, propane, commercial butane, heavier hydrocarbons and nitrogen can be extracted. A proportion of the extracted hydrocarbons can be used as refrigerant make up. A liquefaction unit uses very specific equipment such as cryogenic spool-wound or brazed plate-fin exchangers and high-powered turbo compression units. Two refrigerant cycles in cascade are usually employed

— LNG storage tanks and the relevant loading plants for filling LNG carriers

— generation and/or purchase and distribution of the utilities necessary for the plant to operate (electricity, steam, cooling water, compressed air, nitrogen, fuel gas etc.)