Method and equipment for treating CO2-rich smoke

A process for the treatment of a gas stream comprising a combustion flue gas comprising CO2 in an initial proportion, water vapor, mercury, one or more volatile acidic compounds and one or more additional impurities chosen from oxygen, nitrogen and argon, said process comprising:

• i) cooling the gas stream to a temperature of between approximately −10° C. and approximately −130° C. and a removal of at least one additional impurity and predrying by adsorption/condensation of the stream in order to remove therefrom at least a portion of the water vapor which is present therein, and at least a portion of the mercury by a cooling liquid;
• ii) compressing the gas stream down to a final pressure of between 1 bar and 74 bar absolute;
• and
• iii) recovering a gas stream enriched in CO2 comprising a final proportion of CO2 greater than the initial proportion of CO2 in the stream to be treated,
• wherein the pre-drying by absorption/condensation of the stream is carried out by bringing the gas stream into direct contact with a cooling liquid at a temperature of less than or equal to −20° C.,
• wherein the cooling liquid comprises an aqueous salt or a mixture of aqueous salts.