A wheel lock or clip for maintaining position of a thumbwheel or wheel of a rotary actuated delivery device includes an arcuate or curved body having a live hinge extending therefrom, the hinge connected to an arm having an engagement tooth extending therefrom. The tooth is operatively connected to tab for actuation by a user to disengage the engagement tooth from teeth of gear or barrel of a wheel or a thumbwheel of the rotary actuated device to thereby allow free movement of the wheel or thumbwheel.

Pressure swing adsorption process for reducing fluctuations in the flow rate of tail gas from the adsorption unit. The flow rate of the stream of blowdown gas is regulated responsive signals from a sensor measuring the pressure and/or flow rate of the tail gas comprising the blowdown gas and purge gas effluent before the tail gas is introduced into a surge vessel.

A carbon dioxide recovery system includes: an adsorber configured to adsorb and desorb carbon dioxide; a supply channel through which supply gas passes; a storage section configured to store carbon dioxide desorbed from the adsorber; and a gas supply section supplying carbon dioxide stored in the storage section to the adsorber. The carbon dioxide recovery system is operated in an adsorption mode, a desorption mode or in a desorption preparation mode. In the adsorption mode, the adsorber adsorbs CO.sub.2 contained in the supply gas supplied through the supply channel. In the desorption mode, the adsorber desorbs the adsorbed CO.sub.2, and the storage section stores CO.sub.2 desorbed from the adsorber. In the desorption preparation mode, the gas supply section supplies CO.sub.2 stored in the storage section to the adsorber during a time from an end of the adsorption mode to a start of the desorption mode.

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.

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.

A system for processing biogas, the system comprising: a container, a pressure swing adsorption (PSA) unit housed in the container, the PSA unit having: a plurality of beds containing adsorbent material, the adsorbent material configured to selectively adsorb gas species from the biogas to process the biogas, a rotary valve module for distributing flow of 5 the biogas within the PSA unit, an inlet for supplying the biogas to the plurality of beds from outside of the container, and an outlet for transporting the processed biogas away from the PSA unit.

A controller can be configured to control a system for extracting liquid water from air comprising a thermal unit, a primary desiccant wheel, and a regeneration fluid path. The controller can comprise a sensor, a motor, and a microcontroller coupled to the sensor and the motor. The microcontroller can be configured to determine a water extraction efficiency based on at least one signal received from the sensor, and also can be configured to maximize the water extraction efficiency by adjusting a speed of the motor in response to the determined water extraction efficiency.

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.

The invention relates to a method and system for improving PSA/VPSA plant energy efficiency during times of reduced production demand and capital efficiency through optimizing feed, vacuum, and centrifugal product compressors to achieve lower energy consumption and lower unit gas product production cost. More specifically, the present invention relates to a new energy efficient PSA/VPSA turn down process and system which employs high speed direct drive centrifugal product compressor to achieve desired production. Significant lower energy consumption can be achieved by employing lower flow, and lower adsorption top pressure in the lower production range.

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.