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.

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.

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 hydrogen production apparatus including a desulfurized, a reformer, a CO transformer a gas flow path, and a purge gas supply path which is provided where a purge gas is supplied to an upstream side of a pressure feeding apparatus in the gas flow path, prior to a stopping operation, a purging step of replacing gas within the gas flow path with the purge gas and filling the purge gas into the gas flow path is performed, and in a start-up operation in which a heating means is operated to increase the temperature of the gas within the gas flow path, which is performed prior to a hydrogen purification operation, a pressure increasing step of supplying the purge gas from the purge gas supply path to the closed circulation circuit and increasing the pressure within the closed circulation circuit is performed.

Apparatus and method for carbon dioxide capture and concentration from air for the production of high-purity carbon dioxide. The apparatus comprises a chamber having a CO.sub.2 adsorbent bed attached to a vacuum source, an input air source, a dryer, and a heater. The apparatus allows for control of the chamber's contents, pressure, and temperature. Adsorbents for capturing CO.sub.2 comprise a zeolite, metal organic framework, covalent organic framework, silica, or alumina. The method provides for: flowing air that has been dried through an adsorbent to capture the CO.sub.2; applying a strong vacuum source, or heat and a strong vacuum source to a capture chamber to remove non-CO.sub.2 components as an exhaust stream; and heating and applying a vacuum source to the adsorbent to extract high purity CO.sub.2.

A fuel processing unit includes a fuel line configured to transfer a fuel, a fuel processor including a processing material container configured to contain a processing material configured to remove at least one impurity from the fuel at an elevated temperature above 50 C. to produce a processed fuel, and a thermal treatment device configured to thermally treat the fuel by thermally treating at least one of the fuel line or the processing material container to the elevated temperature.

Disclosed in certain embodiments are methods of removing water from a gas feed stream comprising hydrocarbons and water during an adsorption step of an adsorption cycle.

An adsorption tower according to embodiments of the present disclosure comprises the plurality of beds, an inlet port, an outlet port, at least one sensor unit for each of the plurality of beds, a plurality of connection pipes which connect at least two of the inlet port, the outlet port and the plurality of beds, a plurality of valves connected to the plurality of connection pipes, a memory configured to store one or more instructions, and a processor configured to execute the one or more instructions stored in the memory. The processor is configured to determine a fluid supply order to the plurality of beds according to adsorption values in the plurality of beds measured by the sensor units, and control the fluid supply route by opening and closing the valves according to the determined fluid supply order.

A liquid air energy storage system comprises an air liquefier, a liquid air storage facility for storing the liquefied air, and a power recovery unit coupled to the liquid air storage facility. The air liquefier comprises an air input, an adsorption air purification unit for purifying the input air, and a cold box for liquefying the purified air. The power recovery unit comprise a pump for pressurizing the liquefied air from the liquid air storage facility; an evaporator for transforming the high-pressure liquefied air into high-pressure gaseous air; an expansion turbine capable of being driven by the high-pressure gaseous air; a generator for generating electricity from the expansion turbine; and an exhaust for exhausting low-pressure gaseous air from the expansion turbine. The exhaust is coupled to the adsorption air purification unit such that at least a portion of the low-pressure gaseous air exhausted from the expansion turbine is usable to regenerate the adsorption air purification unit.

Provided herein is a method for improving a gas recovery rate during generation of a high-purity gas. The method includes providing three or more adsorption towers filled with an adsorbent that adsorbs an adsorption target gas. Performing a pressure lowering equalization process in a first adsorption tower in which an adsorption process has been finished, and in a source gas supply state in which a source gas is supplied to at least a second adsorption tower in which a pressure increasing equalization process has been finished and the adsorption process is to be subsequently performed; and transferring a non-adsorbed gas from an upper portion of the first adsorption tower to the upper portion of the second adsorption tower, thereby performing an adsorption and pressure lowering equalization process in the first adsorption tower and an adsorption and pressure increasing equalization process in the second adsorption tower.