Patent ID: 8794029
Filing Date: 2014-08-05
Classification: C07C,F25J,Y02P

Abstract:
1. A process for separating hydrocarbons from a liquefied natural gas, comprising: (a) a step of distilling a feed liquefied natural gas in a first distillation column to separate the feed liquefied natural gas into a fraction enriched with methane and a fraction enriched with components heavier than methane, said first distillation column having a bottom reboiler; (b) a step of distilling the fraction enriched with components heavier than methane in a second distillation column to separate the fraction enriched with components heavier than methane into an overhead gas enriched with ethane and a fraction enriched with components heavier than ethane; (c) a step of recovering cryogenic heat of the liquid inside the first distillation column in a first heat exchanger that is provided separately from the bottom reboiler of the first distillation column, wherein the heat exchanger is in communication with a circulating heat transfer medium that circulates in a closed loop, the heat transfer medium is in a liquid state in the closed loop independent of the feed liquefied natural gas and the liquid inside the first distillation column; (d) a step of condensing at least a part of the overhead gas of the second distillation column in a first condenser by using at least a part of the recovered cryogenic heat in the circulating heat transfer medium from step (c); and (g) a step of returning the circulating heat transfer medium through the closed loop from step (d) to step (c).