METHOD AND SYSTEMS FOR CO2 SEPARATION WITH COOLING USING CONVERGING-DIVERGING NOZZLE

摘要

A method for separating carbon dioxide (CO2) from a gas stream is provided. The method includes cooling the gas stream in a cooling stage to form a cooled gas stream and cooling the cooled gas stream in a converging-diverging nozzle to form one or both of solid CO2 and liquid CO2. The method further includes separating at least a portion of one or both of solid CO2 and liquid CO2 from the cooled gas stream in the converging-diverging nozzle to form a CO2-rich stream and a CO2-lean gas stream. The method further includes expanding the CO2-lean gas stream in an expander downstream of the converging-diverging nozzle to form a cooled CO2-lean gas stream and circulating at least a portion of the cooled CO2-lean gas stream to the cooling stage for cooling the gas stream. Systems for separating carbon dioxide (CO2) from a CO2 stream are also provided.