SEPARATION AT SUB-AMBIENT TEMPERATURE OF A GASEOUS MIXTURE CONTAINING CARBON DIOXIDE AND A LIGHTER CONTAMINANT

摘要

An apparatus for separating a gas mixture containing at least 35 mol%. of carbon dioxide, as well as at least one gas lighter than carbon dioxide comprising a first phase separator (15), a pipe for sending the first partially condensed flow is sent from the exchange line to the first phase separator. phase, a cooling means (23), a pipe for sending a gas from the first phase separator, containing less carbon dioxide than the gas mixture, to be cooled by the cooling means, to form a second partially condensed flow, a second phase separator (27), a line to send the second partially condensed flow to a second phase separator, a first valve (21), a line to send a liquid withdrawn from the first phase separator, containing more carbon dioxide as the mixed gas, relax in the first valve to lower its pressure by at most 300mbar and to form a first expanded liquid and mixing means for mixing the first liquid expanded with a second liquid coming from the second phase separator upstream of a third valve.