Systems and methods are provided for combined cycle power generation while reducing or mitigating emissions during power generation. Recycled exhaust gas from a molten carbonate fuel cell power generation reaction can be separated by using a swing adsorption process so as to generate a high purity CO.sub.2 stream while reducing or minimizing the energy required for the separation and without having to reduce the temperature of the exhaust gas. A high temperature adsorption reactor adsorbs the CO.sub.2 and recovers H.sub.2 from an exhaust gas of a first molten carbonate fuel cell at a high temperature and at a low pressure. The reactor passes along the adsorbed CO.sub.2 to a cathode and the recovered H.sub.2 to an anode of a second molten carbonate fuel cell for further power generation. This can allow for improved energy recovery while also generating high purity streams of CO.sub.2 and H.sub.2.

The present disclosure relates to an apparatus (10) for drying a process gas. The apparatus (10) includes a principal adsorption unit (11) having an inlet (14) for receiving a process gas from a compressor, and an outlet (16) for discharging the process gas. A first supplemental adsorption unit (12) has an adsorbent for adsorbing water. A second supplemental adsorption unit (13) also has an adsorbent for adsorbing water. The apparatus (10) is configured to fluidly connect the outlet of the principal adsorption unit (16) to at least one of the first and second supplemental adsorption units (12, 13). The at least one of the first and second supplemental adsorption units (12, 13) is operable to adsorb water to dry the process gas discharged from the principal adsorption unit. The present disclosure also relates to a method of drying a process gas; a control unit; and a non-transitory computer-readable medium.

Process and apparatuses for purifying a feed stream containing CO.sub.2 and predominantly hydrogen are provided. In an embodiment, the process includes passing the feed stream through a multilayer adsorbent bed comprising a first adsorbent section, a second adsorbent section downstream from the first adsorbent section and a third adsorbent section downstream from the second adsorbent section. The first adsorbent section comprises an activated carbon layer, the second adsorbent section comprises a layer of molecular sieve of the faujasite structure type with a Si/Al atomic ratio of from 1.5 to 8.0 and the third adsorbent section comprises a layer of molecular sieve of the faujasite structure type with a Si/Al atomic ratio of from 1.0 to 1.5. At least one of N.sub.2, CO.sub.2, CH.sub.4 and CO is adsorbed from the feed stream and a purified hydrogen product is recovered from the multilayer adsorbent bed.

A temperature swing adsorption apparatuses and process is disclosed comprising passing a feed stream to a first adsorption bed to adsorb one or more contaminants from the feed stream to produce a product stream. A regeneration gas separator overhead stream is passed to a second adsorption bed to provide a second adsorption bed effluent stream. The second adsorption bed effluent stream is passed to a heater to generate a hot regeneration effluent stream. The hot regeneration effluent stream is passed to a third adsorption bed to regenerate the third adsorption bed and provide a regeneration effluent stream. At least a portion of the regeneration effluent stream is passed to a guard bed to remove sulfur and oxygen compounds to provide a treated regeneration effluent stream. The treated regeneration effluent stream is passed to a regeneration gas separator to provide the regeneration gas separator overhead stream.

In some embodiments, a multistage scrubber that includes a plurality of stages, each stage comprising one or more scrubbing modules having adsorbents configured to adsorb and remove molecules from a flowing mixture of gas traversing the multi-stage scrubber is disclosed. The sorbents may be used in repeatable adsorption-regeneration swing cycles including concentration swing adsorption (CSA) cycle, temperature swing adsorption (TSA) cycle and pressure swing adsorption (PSA) cycle.

Oxygen production process of VSA type from a flow of air, implementing at least one group of at least 3 adsorbers installed in parallel and following the same VSA cycle comprising, in succession, a phase of adsorption at the high pressure of the cycle, a phase of desorption at pressures lower than the high pressure of the cycle, a phase of repressurization of the adsorber to the high pressure of the cycle, characterized in that, periodically or exceptionally: a) at least one adsorber of the group of adsorbers is isolated so as to no longer follow the pressure cycle, b) the adsorbent contained in the adsorber isolated in the step a) is regenerated by raising the temperature, and c) the adsorber regenerated in the step b) is re-incorporated in the group of adsorbers so as to once again follow the pressure cycle.

In various aspects, methods are provided for hydrogen production while reducing and/or mitigating emissions during various refinery processes that produce syngas, such as power generation. Syngas can be effectively separated to generate high purity carbon dioxide and hydrogen streams, while reducing and/or minimizing the energy required for the separation, and without needing to reduce the temperature of the flue gas. In various aspects, the operating conditions, such as high temperature, mixed metal oxide adsorbents, and cycle variations, for a pressure swing adsorption reactor can be selected to minimize energy penalties while still effectively capturing the CO.sub.2 present in syngas.

A sorbent bed assembly of a fuel cell system, including a first sorbent bed, a second sorbent bed and at least one third sorbent bed, the second sorbent bed disposed between the first sorbent bed and the at least one third sorbent bed, a cover plate on the plurality of sorbent beds and configured to connect the sorbent beds to one another, a fuel inlet connector on the cover plate and configured to receive a fuel, a manifold having a first fluid conduit configured to transport fuel between the first sorbent bed and at least one third sorbent bed, and a second fluid conduit configured to transport fuel between at least one third sorbent bed and the second sorbent bed, and a fuel outlet connector on the cover plate and configured to receive fuel that has passed through each of the sorbent beds.

Biogas containing H.sub.2S and CO.sub.2 is upgraded by removing H.sub.2S using PTSA and CO.sub.2 using two stages of gas separation membranes. The first stage permeate may optionally be used a regeneration gas stream. The second stage permeate may optionally be used a cool down gas stream. The PTSA unit includes two or more adsorbent beds each selective for water, VOCs, and H.sub.2S over CO.sub.2 and for H.sub.2S over methane.

The present invention proposes a gas treatment process in which a process arrangement comprising three process units is used, the gas treatment process comprising subsequently operating a different one of the three process units in a heating mode during a heating phase, the heating mode comprising heating a first gas stream to a first temperature level using a first heat exchanger, introducing the first gas stream at the first temperature level to the process unit which is operated in the heating mode, withdrawing a second gas stream from the process unit which is operated in the heating mode, and thereafter cooling the second gas stream to a second temperature level using a second heat exchanger.