Comparison between different Boil Off Gas compression alternatives in Liquefied Natural Gas Storage Tanks

Remiro Hernández, Jesús Ángel

Boil Off Gas (BOG) and End Flash Gas (EFG) handling in Liquefied Natural Gas (LNG) Production Facilities is a key point for the operation. During normal operation continuous flaring is not permitted and the plant is designed such that the generated BOG+EFG is used as fuel gas, via compression systems. These facilities usually operate under two different modes: ship-loading/unloading (liquefaction/regasification plants) and holding mode, both with quite a different behavior in terms of BOG/EFG generation. BOG compressors flexibility, over the whole generation range, is one of the key points for the compression system configuration analysis (linked to an electrically efficient consumption). This paper discusses the advantages and disadvantages of each type of BOG compressor technology cons