Patent ID: 9605896
Date: 2017-03-28
CPC Classifications: F25J,Y02C

Claim:
1. A process for treating a natural gas containing carbon dioxide, the process comprising: separating the natural gas by a cryogenic process in order to provide a stream of liquid carbon dioxide containing hydrocarbons and purified natural gas; cooling at least one part of the natural gas: recovering at least one part of the stream of liquid carbon dioxide in order to provide a stream of recycled carbon dioxide; dividing the stream of recycled carbon dioxide into a first portion and a second portion; expanding and then heating the first portion in the first heat exchanger, in order to provide a first stream of heated carbon dioxide; cooling the second portion, then expanding and then heating at least one part of the second portion in the second heat exchanger, in order to provide a second stream of heated carbon dioxide; and recovering at least some of the hydrocarbons contained in the first stream of heated carbon dioxide and in the second stream of heated carbon dioxide by liquid/gas separation; the first stream of heated carbon dioxide undergoing a liquid/gas separation in a first separation flask in order to provide a first gaseous phase and a first liquid phase; expanding the first liquid phase; and the second stream of heated carbon dioxide and the first expanded liquid phase undergoing a liquid/gas separation in a second separation flask in order to provide a second gaseous phase and a second liquid phase.