A portable oxygen concentrator designed for medical use where the sieve beds, adsorbers, are designed to be replaced by a patient. The concentrator is designed so that the beds are at least partially exposed to the outside of the system and can be easily released by a simple user-friendly mechanism. Replacement beds may be installed easily by patients, and all gas seals will function properly after installation.

Disclosed is an improved method and system of operating the semi-closed cycle, which both reduces parasitic loads for oxygen generation and for gas clean up, while also reducing, capital cost of the gas clean up plant (reduced drying requirement) and of the oxygen plant (enabling membranes vs. mole sieves). The invention is applicable to piston or turbine engines, and results in a near fully non-emissive power system via the Semi-Closed Cycle (SCC), in a manner which both captures carbon in the form of carbon dioxide, CO2, and in a manner which improves the efficiency and cost effectiveness of prior disclosures. The captured carbon is of a purity and pressure directly suitable for Enhanced Oil Recovery (EOR), sequestration, or industrial use.

Systems and methods presented herein provide for multivariable model predictive control of a multistep plant. In one embodiment, a model predictive controller (MPC) includes a model of the multistep plant. The MPC is operable to linearize at least two steps of the multistep plant into cycle steps based on the model, to process an output signal from the multistep plant, and to independently control the cycle steps based on the output signal to optimize an output of the multistep plant.

Systems and methods for producing oxygen enriched air using vacuum pressure swing adsorption (VPSA) are disclosed. In one implementation, an oxygen concentrator includes a canister system having at least one canister, a pumping system having at least one motor-controlled pump, a set of valves pneumatically coupling the canister system and the pumping system, and a controller. The canister is configured to receive a gas separation adsorbent. The controller is configured to control operation of the pumping system and the set of valves to: selectively pneumatically couple the motor-controlled pump and the canister so as to pressurize the canister and selectively pneumatically couple the motor-controlled pump and the canister so as to evacuate the canister.

A pressure swing adsorption process is provided to remove oxygen from a hydrogen stream through the use of a copper material in combination with layers of adsorbent to remove water, C2 and C3 hydrocarbons, as well as other impurities. The feed gas comprises more than 70 mol % hydrogen, at least 1 mol % methane and more than 10 ppmv oxygen. The purified product hydrogen stream comprises greater than 99 mol % hydrogen, with less than 1 ppmv oxygen.

The present disclosure pertains to a system configured to generate oxygen including a compressor configured to intake and pressurize gas, an oxygen separation unit comprising a first sieve bed, a second sieve bed, and an input receiving the stream of gas from an output of the compressor. The oxygen separation unit generates an oxygen flow by separating oxygen from the stream of gas. A membrane module in fluid connection with an output of the oxygen separation unit is configured to purify the oxygen flow generated by the oxygen separation unit. A valve arrangement is configured to direct, periodically, at least some of the oxygen flow from the membrane module through the sieve beds to purge the sieve beds with retentate gas and exhaust such retentate gas. One or more processors control the valve arrangement, so as to control the oxygen flow and purging of the sieve beds.

An adsorption process is provided to remove oxygen from a hydrogen stream through the use of a copper material in combination with layers of adsorbent to remove water and nitrogen from a hydrogen stream. This process is particularly useful for purification of hydrogen product gas from water electrolyzers with the hydrogen product gas having greater than 99.9 mol % purity.

Apparatus, such as a portable oxygen concentrator (100) or other device communicating therewith, may be configured, such as with a processor(s), to estimate a remaining capacity of a sieve bed of the concentrator. Such apparatus may be configured to access a parameter of a measured pressure-time characteristic of the sieve bed for a phase of a pressure swing adsorption cycle of the oxygen concentrator. The apparatus may be configured to access function(s) of the parameter of the pressure-time characteristic and operational characteristic(s) of the sieve bed. The apparatus may be configured to estimate the remaining capacity by applying the function(s) to the parameter of the measured pressure-time characteristic. Such an estimate may then serve as a basis for providing notification, such as on a display or by electronic messaging, to inform of remaining life of the sieve bed, or otherwise promote timely replacement of a depleting component.

An oxygen production system (100) may include a main control module (120) and a molecular sieve module (140). The molecular sieve module (140) may include a molecular sieve and a molecular sieve information unit. The molecular sieve information unit may be configured to store information of the molecular sieve. The main control module (120) may be configured to read, write and/or update the information of the molecular sieve stored in the molecular sieve information unit. When reading, in response to at least part of the information of the molecular sieve exceeding a preset range, the main control module (120) may control the oxygen production system (100) to perform a corresponding operation. The oxygen production system (100) may occupy small space, have good performance and a high oxygen production efficiency, and enable a user to obtain a more user-friendly experience.

An adsorption process is provided to remove oxygen from a hydrogen stream through the use of a copper material in combination with layers of adsorbent to remove water and nitrogen from a hydrogen stream. This process is particularly useful for purification of hydrogen product gas from water electrolyzers with the hydrogen product gas having greater than 99.9 mol % purity.