A system and a process for capturing Carbon Dioxide (CO.sub.2) from flue gases are disclosed. The process comprises feeding a flue gas comprising CO.sub.2 to at least one Rotary Packed Bed (RPB) absorber rotating circularly. A solvent may be provided through an inner radius of the RPB absorber. The solvent may move towards an outer radius of the RPB absorber. The solvent may react with the flue gas in a counter-current flow. The process further includes passing the flue gas through at least one of a water wash and an acid wash to remove traces of the solvent present in the flue gas. Finally, the solvent reacted with the CO.sub.2 may be thermally regenerated for re-utilizing the solvent back in the process.

CO.sub.2 capture processes and systems can be improved by recovering thermal energy from particular streams for reuse in the stripping stage. Thermal energy can be recovered from the overhead gas stream of a stripper operated under vacuum pressure conditions, and thermal energy can also be recovered from a flue gas. A heat transfer circuit can be implemented for recovering thermal energy by indirect heat transfer from the overhead gas stream, a flue gas stream, and/or other streams to a heat transfer fluid. The heat transfer circuit can include multiple heat recovery loops arranged in parallel and the heated fluid can be supplied through a reboiler of the stripper to heat the solution in the reboiler.

An absorption liquid regeneration apparatus includes: a regeneration tower for regenerating a CO.sub.2 absorption liquid; a reflux water drum configured to separate released gas from the regeneration tower into CO.sub.2 gas and condensed water, and return the condensed water to the regeneration tower; and a cleaning part installed in a gas-phase part of the reflux water drum or in a CO.sub.2 flow passage through which the CO.sub.2 gas having flowed from the gas-phase part flows, and configured to remove a CO.sub.2 absorption agent contained in the CO.sub.2 gas by using a cleaning liquid. The cleaning liquid has a lower concentration of the CO.sub.2 absorption agent than the condensed water stored in a liquid-phase part of the reflux water drum.

The use of the combination of (a) an amino compound and (b) a compound including a soft electrophilic centre to scavenge and retain acidic sulfide species at a higher temperature and/or scavenge acidic sulfide species at an increased rate compared to that achieved using the amino compound alone.

A process for the absorption of a target gaseous component from a gas stream comprising the steps of: contacting the gas stream with an absorber comprising an liquid absorbent for absorbing the target gaseous component to produce a rich liquid absorbent stream and a non target gaseous component, said non target gaseous component including water vapour; treating the rich liquid absorbent stream in a desorber to thereby release the target gaseous component and a water vapour component into a desorber gas stream and produce a lean liquid absorbent stream; and forming a recovered water stream from the output of a water separator for separating the water vapour from the target gaseous component, said water separator forming part of the absorber and/or the desorber. The lean liquid absorbent stream exiting the desorber is treated with a forward osmosis (FO) membrane unit comprising a water permeable membrane, wherein the membrane unit transfers water from a salt water stream through the water permeable membrane to the lean liquid absorbent stream, thereby replenishing at least part of the water removed in the process.

A metal lattice for a carbon dioxide scrubber may comprise a metal lattice body defining a plurality of intersecting ligaments, wherein nodes are formed at said intersections. In various embodiments, the metal lattice may be manufactured using an additive manufacturing process. A node density of the metal lattice may vary. A ligament thickness of the metal lattice may vary. The metal lattice may comprise liner defining a channel extending through the metal lattice.

An acid component removal device for removing an acid component from an acid gas absorbent containing an amine, comprising: an anode; a cathode; and an electrodialysis structure having four compartments formed by arranging an first membrane which is either an anion exchange membrane or a cation exchange membrane, a second membrane which is a bipolar membrane, and a third membrane which is either an anion exchange membrane or a cation exchange membrane and which is the other of the first membrane, in this order, from the anode end to the cathode end between the anode and the cathode, with a space each between the membranes.

An absorbent composition including an amino-siloxane is presented. The amino-siloxane includes structure (I): wherein R.sup.1 is independently at each occurrence a C.sub.1-C.sub.6 aliphatic or aromatic radical; R.sup.2 is independently at each occurrence a C.sub.2-C.sub.10 aliphatic or aromatic radical; and R.sup.3 is independently at each occurrence a C.sub.1-C.sub.18 aliphatic or aromatic radical or R.sup.4′ wherein R.sup.4 comprises structure (II): wherein X is independently at each occurrence an electron donating group; and n is at least 1. Methods of reducing an amount of carbon dioxide in a process stream using the absorbent composition are also presented.

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It has been discovered that mixed-alcohol production can utilize the waste tail gas stream from the pressure-swing adsorption section of an industrial hydrogen plant. Some variations provide a process for producing mixed alcohols, comprising: obtaining a tail-gas stream from a methane-to-syngas unit (e.g., a steam methane reforming reactor); compressing the tail-gas stream; separating the tail-gas stream into at least a syngas stream, a CO.sub.2-rich stream, and a CH.sub.4-rich stream; introducing the syngas stream into a mixed-alcohol reactor operated at effective alcohol synthesis conditions in the presence of an alcohol-synthesis catalyst, thereby generated mixed alcohols; and purifying the mixed alcohols to generate a mixed-alcohol product. Other variations provide a process for producing clean syngas, comprising: obtaining a tail-gas stream from a methane-to-syngas unit; compressing the tail-gas stream; separating the tail-gas stream into at least a syngas stream, a CO.sub.2-rich stream, and a CH.sub.4-rich stream; and recovering a clean syngas product.

The combined acid gas removal and water filtration system (10) removes sour gases, such as hydrogen sulfide (H2S) and carbon dioxide (CO2), from an input gaseous hydrocarbon stream (FG), as well as producing purified water (TW). The acid gas removal system (10) has a contactor (12) for contacting the input gaseous stream (FG) with an absorption liquid solvent (ALS), and a stripper (24) for recycling the absorption liquid solvent (ALS) and removing acidic gases (AG) therefrom. A first heat exchanger (22) heats used absorption liquid solvent (UALS) output from the contactor (12) prior to injection into the stripper (24). A second heat exchanger (26) cools recycled absorption liquid solvent (RALS) using a refrigerant (R) before injection back into the contactor (12). The refrigerant (R) is coupled with an absorber (84), which receives a dilute ethanolic draw solution (DDS) from a forward osmosis filtration system (72), producing purified water (TW).