A control circuit of an oxygen concentrator maintains pressure within a compressor of the oxygen concentrator. The control circuit includes a microprocessor that controls functioning of a controller based on two or more of: a user-adjustable flow rate of oxygen delivered by the oxygen concentrator to a user, an ambient temperature, and an ambient pressure. The functioning of the controller further controls the adsorption of various gases by sieve beds of the oxygen concentrator to produce oxygen enriched gas.

A passive valve for use as a fixed leak valve. The valve includes a body having an internal chamber, first and second body ports in fluid communication with the chamber with the first port configured for fluid communication with a patient connection and the second body port configured for fluid communication with a ventilator, a body passageway in fluid communication with the chamber and with ambient air exterior of the body, and a check valve seal positioned to seal the body passageway to permit the flow of gas within the chamber through the body passageway to the exterior of the body and to prevent the flow of ambient air exterior of the body through the body passageway into the chamber. In alternative embodiments, the valve is incorporated into the patient connection or constructed as a separate part connectable to the patient connection.

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.

Provided are apparatus and systems for performing a swing adsorption process. This swing adsorption process may involve passing an input feed stream through two swing adsorption systems as a purge stream to remove contaminants, such as water, from the respective adsorbent bed units. The wet purge product stream is passed to a solvent based gas treating system, which forms a wet hydrocarbon rich stream and a wet acid gas stream. Then, the wet hydrocarbon rich stream and the wet acid gas stream are passed through one of the respective swing adsorption systems to remove some of the moisture from the respective wet streams.

A portable oxygen concentrator designed for medical use where the adsorbent beds, are designed to be replaced by a patient. The concentrator is designed so that the power supply and adsorbent bed mount is one module and the compressor and air filter are part of another module configured to provide a unitary cooling and air supply system. Replacement beds may be installed easily by patients, and all gas seals will function properly after installation.

A wearable oxygen concentrator can be used in both an ambulatory mode and a stationary mode. The wearable oxygen concentrator is physically connected to a docking station in the stationary mode such that it can draw power from the docking station and remain energy efficient in both modes. The disclosed oxygen generation system incorporates effective gas flow by means compressor configurations for use in lower flow ambulatory modes and higher flow stationary modes.

A gas separation and recovery method is provided. Based on the fact that a gas adsorbent has differing adsorption and desorption characteristics depending on the affinities and pressures of gas species, and gases of different species are desorbed at different timings, a target gas component is separated and recovered from a source gas by a pressure swing adsorption process in such a manner that a desorption step is divided into, for example, two time periods and desorbed gases are recovered separately in the respective time periods. In this manner, when gas 1 and gas 2 having different desorption timings are adsorbed to an adsorbent, a gas rich in gas 1, and a gas rich in gas 2 may be recovered separately from each other. Thus, it becomes possible to separate and recover selectively a target gas component with high concentration.

A multi-stage process to remove contaminant gases from raw methane streams is provided. The present technology is an innovative solution to recover and purify biogas by use of a process having at least two pressure swing adsorption stages. Taking advantage of the presence of carbon dioxide in the raw biogas streams, nitrogen and oxygen are bulky removed in the first stage, using selective adsorbents, and a nitrogen and oxygen-depleted intermediate stream is yielded to the second stage. The second stage employs an adsorbent or adsorbents to selectively remove carbon dioxide and trace amounts of remaining nitrogen and oxygen, thus producing a purer methane stream that meets pipeline and natural gas specifications

Disclosed is a flue gas low-temperature adsorption denitration system and process. The system includes a booster fan, a cold energy recoverer, a flue gas cooling system, a flue gas switching valve, and two denitration adsorption towers. An inlet of the booster fan is in communication with an inlet flue gas pipeline. The booster fan, the cold energy recoverer, the flue gas cooling system, the flue gas switching valve, and the denitration adsorption towers are sequentially communicated. An outlet of the flue gas switching valve is in communication with each of the two second denitration adsorption towers. Flue gas outlets of the two denitration adsorption towers are in communication with a flue gas manifold. The flue gas manifold is communicated with the cold quantity recoverer. Two denitration adsorption towers take turns to carry out denitration and regeneration processes, so that continuous denitration operations of the system can be achieved.

A first process and sorbent for removing ammonia from a gaseous environment, the sorbent comprised of graphene oxide having supported thereon at least one compound selected from metal salts, metal oxides and acids, each of which is capable of adsorbing ammonia. A second process and sorbent system for removing ammonia and a volatile organic compound from a gaseous environment; the sorbent system comprised of two graphene-based materials: (a) the aforementioned graphene oxide, and (b) a nitrogen and oxygen-functionalized graphene. The sorbents are regenerable under a pressure gradient with little or no application of heat. The processes are operable through multiple adsorption-desorption cycles and are applicable to purifying and revitalizing air contaminated with ammonia and organic compounds as may be found in spacesuits, aerospace cabins, underwater vehicles, and other confined-entry environments.