A carbon dioxide conversion system for an environment includes a first gas-liquid contactor-separator downstream of the environment; an electrochemical conversion cell downstream of the first gas-liquid contactor-separator; and a cleaned ionic liquid storage intermediate the first gas-liquid contactor-separator and the electrochemical conversion cell.

Separating oxygen from a gas includes contacting an oxygen-selective sorbent with a gas stream, adsorbing oxygen in the gas stream with the sorbent, heating the sorbent to greater than 400° C., and desorbing a majority of the oxygen. The sorbent is selective for oxygen, and adsorbing occurs at a temperature between 275-325° C. An oxygen separation system includes a sorption bed, a heater configured to heat the sorption bed, an oxygen analyzer, a first conduit configured provide an input gas to the sorption bed, a second conduit configured to provide processed input gas from the sorption bed to the oxygen analyzer, a third conduit configured to provide a purge gas to the sorption bed, and a fourth conduit configured to provide processed purge gas to the oxygen analyzer. The first and third conduits are configured to flow the input gas and the purge gas flow in opposite directions through the sorption bed.

An article of manufacture for providing an O.sub.2 Tree for removing CO.sub.2 gas from the atmosphere according to the present invention is disclosed.

An oxygen concentrator 100 apparatus and a method thereof implement operations control to efficiently release oxygen enriched gas to reduce potential waste. The control methodology may include generating a profile such as a minimum inhalation flow profile of the user. The profile may be based on a size parameter of the user. The method may determine one or more control parameters characterizing a bolus of oxygen enriched gas based on the generated flow profile. The control methodology may then generate a bolus release control signal, such as for a supply valve, according to the determined one or more control parameters. The oxygen concentrator may then, with the control signal, release and deliver a bolus of oxygen enriched gas for a user such as for reducing waste.

A user-replaceable receptacle for an oxygen concentrator includes a containment structure and a desiccant disposed within the containment structure. An inlet end of the containment structure allows feed gas to be introduced into the desiccant. An outlet end of the containment structure allows the feed gas to exit the containment structure. A connection mechanism couples the outlet end of the containment structure to a gas separation adsorbent. The connection mechanism is operable between an unconnected position and a connection position. The desiccant in the user-replaceable receptacle removes water moisture from the feed gas prior to exiting the outlet end of the containment structure, thereby reducing exposure of the gas separation adsorbent to water.

Oxygen concentrator apparatus provides variation in therapy gas during a breathing cycle such as by varying flow rate and/or oxygen purity of enriched air. The apparatus may include a compressor and a valve set that operates sieve bed(s) for the enriching air and to vent exhaust gas from the bed(s). The therapy gas may include released enriched air and exhaust gas. The apparatus has a supply valve to selectively release enriched air from an accumulator via a primary path to a delivery conduit. The apparatus may include a secondary path, such as with a valve, to release a portion of exhaust gas to the delivery conduit. A controller actuates the valve set to produce the enriched air, and the supply valve to release enriched air to the delivery conduit. The controller may actuate the secondary valve in anti-sync with the supply valve to release exhaust gas to the delivery conduit.

A portable oxygen concentrator includes at least one separation mechanism and an oxygen storage tank, where the separation mechanism is connected to the oxygen storage tank and includes an air bag and a molecular sieve tank that is filled with a molecular sieve for adsorption. The air bag has an air inlet and an air outlet. The air bag is connected to the molecular sieve tank through a valve group, which includes a first single valve and a second single valve. The air bag is connected to the molecular sieve tank through the first single valve. Each of the two ends of the molecular sieve tank has at least one gas outlet. When an inner space of the air bag is compressed and expanded once, the molecular sieve in the molecular sieve tank adsorbs and desorbs once.

Described is the use of a mineral comprising a metal carbonate fraction and a fuel fraction, such as oil shale or coal shale, in a calcination process. The disclosed process can advantageously result in carbon dioxide being removed from the atmosphere. Further, in the process, heat energy generated during calcination can be used to separate oxygen from air, so that the oxygen can be fed back into the system. Alternatively or in addition, heat energy may also be used to compress the gaseous carbon dioxide generated from the calcination process.

A portable oxygen concentrator retrofit system and method in which an existing portable oxygen concentrator may be retrofitted to output an enriched oxygen gas at a flow rate suitable for use in a patient ventilation system without the need for an external source of compressed gas.

Compressed air dryer systems are described. In an aspect, a system includes, but is not limited to, a plurality of dryer modules and a controller operable to regulate a run-time of each of the plurality of dryer modules. Each dryer module is configured to direct a portion of cooling medium past a stream of compressed air. Each dryer module includes a temperature sensor in thermal communication with the portion of cooling medium, and a chiller configured to reduce a temperature of the portion of cooling medium based on the sensed temperature and a temperature set-point. The controller communicatively is coupled with the plurality of dryer modules and operable to monitor a plurality of run-times. Each run-time is associated with a corresponding dryer module. The controller is further operable to direct operation of each dryer module based on its run-time by modifying the temperature set-point of the dryer module.