A heat exchange assembly for treating carbon dioxide (CO.sub.2) is described. The heat exchange assembly includes a housing that includes an inlet, an outlet, and an inner surface that defines a cavity extending between the inlet and the outlet. The housing is configured to receive solid CO.sub.2 through the inlet. At least one heat exchange tube extends through the housing. The heat exchange tube is oriented to contact solid CO.sub.2 to facilitate transferring heat from solid CO.sub.2 to a heat exchanger fluid being channeled through the heat exchange tube to facilitate converting at least a portion of solid CO.sub.2 into liquid CO.sub.2. The heat exchange assembly is configured to recover a refrigeration value from the solid CO.sub.2 and transfer at least a portion of the recovered refrigeration value to a flue gas.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH & DEVELOPMENT
 This invention was made with Government support under Contract No. DE-AR0000101, awarded by the Department of Energy. The Government has certain rights in this invention.