To separate a hydrocarbon such as ethane from a liquefied natural gas at low cost while saving energy, without worsening easiness and reliability in an operation.
This method of separating the hydrocarbon from the liquefied natural gas has a process for distilling a raw liquefied natural gas in the first distillation column to be separated into a fraction enriched with methane and a fraction enriched with components heavier than methane; a process for distilling the fraction enriched with components heavier than methane in the second distillation column to be separated into a fraction enriched with ethane and a fraction enriched with components heavier than ethane; a process for recovering cold heat of the raw liquefied natural gas fed to the first distillation column or an internal liquid inside the first distillation column, by a heat transfer medium; and a process for cooling overhead gas of the second distillation column by the heat transfer medium with recovered cold heat to condense at least one part of the overhead gas of the second distillation column. The present invention provides also a device for carrying out the method.
YAMAGUCHI SHOICHI
TAMAKOSHI AKIHIKO
Ishibashi Masayuki
Masaaki Ogata