METHOD AND APPARATUS FOR THE LIQUEFACTION OF CO2

摘要

In a method for the liquefaction of a gas containing at least 60 mol % of CO2, in order to produce at least one liquid product, a first feed gas is compressed from a first pressure to a second pressure and cooled so as to form a liquid or supercritical flow, at least part of the liquid or supercritical flow is cooled in a heat exchanger (E1) in order to form a cyclic liquid at the second pressure, the cyclic liquid is divided into at least two fractions, including an auxiliary fraction, at least one fraction being vaporised in the exchanger by means of heat exchange with the liquid or supercritical flow part, and where there are at least two fractions, each one is vaporised at a different pressure, and the at least one gas formed is then compressed and mixed with the first feed gas, the auxiliary fraction (13) either forming the liquid product or one of the liquid products, or being treated by separation at a sub-ambient temperature in at least one separating means (P1,P3) in order to form the liquid product.