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.

Methods are provided for the production of nitrogen, hydrogen, and carbon dioxide from an exhaust gas. Exhaust gas from combustion in a fuel rich (or reducing) atmosphere is primarily composed of CO.sub.2, CO, N.sub.2, H.sub.2O, and H.sub.2. CO may be converted to CO.sub.2 and H.sub.2 via the water gas shift reaction. Carbon dioxide may then be effectively separated from nitrogen and hydrogen to produce a carbon dioxide stream and a nitrogen/hydrogen stream. The nitrogen/hydrogen stream may then be effectively separated to produce a high purity nitrogen stream and a high purity hydrogen stream. The process may be done in any order, such as separating the nitrogen first or the carbon dioxide first.

The invention concerns an optimization method for a pressure swing adsorption process for separating CO.sub.2 from a feed gas by adapting the ratio of rinse steam to purge steam at a fixed amount of total steam.

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.

One embodiment of the present invention sets forth a technique for operating an oxygen concentrator. The technique includes measuring a product gas within an oxygen concentrator to produce a product gas measurement, and determining that an output of the oxygen concentrator is fluidly connected to a respiratory ventilation device based on the product gas measurement. The technique further includes, in response to determining that the oxygen concentrator is fluidly connected to the respiratory ventilation device, determining that the output of the oxygen concentrator does not meet a supply gas requirement of the respiratory ventilation device and, in response to determining that the output of the oxygen concentrator does not meet the supply gas requirement, adjusting a control output in the oxygen concentrator to modify operation of the oxygen concentrator.

A fuel cell system includes a fuel cell, a reactant intake, and an impurity removal system. The fuel cell includes an inlet and an outlet opposite the inlet. The reactant intake is configured to direct a reactant stream toward the inlet of the fuel cell. The impurity removal system is arranged downstream of the reactant intake and configured to remove impurities from the reactant stream to form a purified reactant stream that is directed into the inlet of the fuel cell.

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.