Systems and methods are described for re-moving solidifiable gas from a process gas stream by direct contact with a cold liquid. The process gas stream includes at least gas that is frozen by the cold liquid while one or more other gases of the process gas stream remain in a gaseous state. The process gas stream may include water, and will have a different composition than the cold liquid. The contacting of the cold liquid with the process gas stream may be at a pressure that is less than 200 psia, and optionally less than 100 psia, 50 psia, or even 30 psia, and the solidified gas may be removed from the contacting assembly as a slurry with cold liquid.

Systems and methods are described for re-moving solidifiable gas from a process gas stream by direct contact with a cold liquid. The process gas stream includes at least gas that is frozen by the cold liquid while one or more other gases of the process gas stream remain in a gaseous state. The process gas stream may include water, and will have a different composition than the cold liquid. The contacting of the cold liquid with the process gas stream may be at a pressure that is less than 200 psia, and optionally less than 100 psia, 50 psia, or even 30 psia, and the solidified gas may be removed from the contacting assembly as a slurry with cold liquid.

Systems and methods of CO.sub.2 desublimation are presented in which refrigeration content is retained within the system. Most preferably, refrigeration content is recycled by providing the refrigeration content of a CO.sub.2-lean feed gas to the CO.sub.2-containing feed gas and to pre-cooling of a desublimator, and/or by providing refrigeration of effluent of a desublimator in regeneration to a refrigerant in a closed refrigeration cycle for deep-cooling of another desublimator.

Systems and methods of CO.sub.2 desublimation are presented in which refrigeration content is retained within the system. Most preferably, refrigeration content is recycled by providing the refrigeration content of a CO.sub.2-lean feed gas to the CO.sub.2-containing feed gas and to pre-cooling of a desublimator, and/or by providing refrigeration of effluent of a desublimator in regeneration to a refrigerant in a closed refrigeration cycle for deep-cooling of another desublimator.

A crystallization column and a crystallization method. The crystallization column comprises an upper head (1), a tower body (2) and a lower head (3), wherein a crystallization section (11) is provided with a tray (14); and the tray (14) comprises a tray plate (15) and a plurality of lower crystallization members (17). The top end of the lower crystallization member (17) can form a movable connection with the tray plate (15), so that the two adjacent lower crystallizing members (17) are capable of oscillating collisions. The tray (14) may also comprise a plurality of upper crystallization members (21) extending upwardly from the upper surface of the tray plate (15).

A crystallization column and a crystallization method. The crystallization column comprises an upper head (1), a tower body (2) and a lower head (3), wherein a crystallization section (11) is provided with a tray (14); and the tray (14) comprises a tray plate (15) and a plurality of lower crystallization members (17). The top end of the lower crystallization member (17) can form a movable connection with the tray plate (15), so that the two adjacent lower crystallizing members (17) are capable of oscillating collisions. The tray (14) may also comprise a plurality of upper crystallization members (21) extending upwardly from the upper surface of the tray plate (15).

A wetted-wire liquid-gas contactor device is disclosed comprising a plurality of wires, a first support structure configured to retain the plurality of wires, and a liquid distribution system for receiving and distributing a liquid to the plurality of wires. The diameter of the plurality of wires is approximately 2 mm or less, wherein a pitch of the plurality of wires is less than 4.0 mm.

A wetted-wire liquid-gas contactor device is disclosed comprising a plurality of wires, a first support structure configured to retain the plurality of wires, and a liquid distribution system for receiving and distributing a liquid to the plurality of wires. The diameter of the plurality of wires is approximately 2 mm or less, wherein a pitch of the plurality of wires is less than 4.0 mm.

A process to prevent fouling using a desublimating heat exchanger is disclosed. An outlet stream from the desublimating heat exchanger may be split into a plurality of parallel streams. The parallel streams may be sent through other devices for performing a unit operation, and the devices for performing a unit operation may change the temperature of at least one of the parallel streams. Parallel streams of differing temperature may emerge from the devices for performing a unit operation. The parallel streams of differing temperature may be sent to a mixing chamber. A mixed stream of uniform temperature may emerge from the mixing chamber, and the mixed stream may be recycled back to the desublimating heat exchanger. The mixing chamber may be separate from the desublimating heat exchanger, or the parallel streams of differing temperature may be mixed in the desublimating heat exchanger.

A process to prevent fouling using a desublimating heat exchanger is disclosed. An outlet stream from the desublimating heat exchanger may be split into a plurality of parallel streams. The parallel streams may be sent through other devices for performing a unit operation, and the devices for performing a unit operation may change the temperature of at least one of the parallel streams. Parallel streams of differing temperature may emerge from the devices for performing a unit operation. The parallel streams of differing temperature may be sent to a mixing chamber. A mixed stream of uniform temperature may emerge from the mixing chamber, and the mixed stream may be recycled back to the desublimating heat exchanger. The mixing chamber may be separate from the desublimating heat exchanger, or the parallel streams of differing temperature may be mixed in the desublimating heat exchanger.