Abstract: The method serves for operating an air fractionization installation for obtaining oxygen on board an aircraft, with at least two molecular sieve chambers. A part mass flow of the oxygen obtained in the respective adsorbing molecular sieve chamber is supplied for flushing a desorbing molecular sieve chamber. The quantity of the flushing oxygen led to the desorbing molecular sieve chamber is controlled by way of this.

Abstract: The present invention is directed to an improved integrated process for the removal of heavy hydrocarbons, carbon dioxide, hydrogen sulfide, and water from a raw natural gas feed stream. More specifically, the integrated process of the present invention comprises a three step process involving the adsorption of heavy hydrocarbons and water on an adsorbent bed selective for the same, a subsequent aqueous lean amine treatment for the absorptive removal of acid gases, such as carbon dioxide and hydrogen sulfide, and an adsorptive removal of water. The process of the present invention results in a highly purified dry natural gas product stream.

Abstract: Pressure swing adsorption (PSA) assemblies with temperature-based breakthrough detection systems, as well as to hydrogen-generation assemblies and/or fuel cell systems containing the same, and to methods of operating the same. The detection systems are adapted to detect a measured temperature associated with adsorbent in an adsorbent bed of a PSA assembly and to control the operation of at least the PSA assembly responsive at least in part thereto, such as responsive to the relationship between the measured temperature and at least one reference temperature. The reference temperature may include a stored value, a previously measured temperature and/or a temperature measured elsewhere in the PSA assembly. In some embodiments, the reference temperature is associated with adsorbent downstream from the adsorbent from which the measured temperature is detected.

Abstract: An adsorption dryer includes a pressure vessel containing the drying agent in a cylindrical chamber, which is in the form of a cylindrical tubing section. The pressure vessel is axially clamped between a bottom and a top distributor plate. In the cylindrical chamber of the pressure vessel, the drying agent is enclosed between a bottom piston and a top piston. The two pistons are radically sealed against the inside of the wall of the pressure vessel. Tongue and groove connections between the wall of the pressure vessel and the piston can hold the pistons axially. The bottom and top distributor plates are clamped with the pistons by means of threaded bolts. The tongue and groove connection between the piston and the pressure vessel and the bolt connection of the distributor plates with the pistons ensure comparatively low cost of production and assembly.

Abstract: A water production unit is provided having two modes of operation for extracting water from exhaust and air.

Abstract: An air drying arrangement for a commercial vehicle is provided having two or more desiccant canisters arranged in parallel on a single air dryer body. The arrangement may include an coupling device that attaches to the body and allows the two or more desiccant containing canisters to mount to the device. The arrangement may be configured to balance the flow of air to each of the desiccant containing canisters when drying air and/or when regenerating the desiccant.

Abstract: Oxygen concentrator system having a portable oxygen generator unit adapted to generate a non-humidified oxygen-rich gas and a stationary base unit adapted to generate a humidified oxygen-rich gas, wherein the portable oxygen generator unit and the stationary base are adapted for operation in a coupled mode and an uncoupled mode. The portable oxygen generator unit includes a first flow coupling adapted to receive the humidified oxygen-rich gas when operating in the coupled mode, piping means adapted to combine the non-humidified oxygen-rich gas and the humidified oxygen-rich gas to form a humidified oxygen-rich gas product, and an oxygen-rich gas product delivery port. The stationary base unit is adapted to recharge a rechargeable power supply system in the portable oxygen generator unit when the units are coupled.

Abstract: Decontamination systems and methods are disclosed. In one embodiment, a system comprises a first adsorption/desorption subsystem that is configured to receive a contaminated gaseous solution and remove substantially all of the contaminants from the contaminated gaseous solution during an adsorption cycle, while a second subsystem is configured to purge captured contaminants during a desorption cycle. An evacuator is configured to drive potentially flammable gas compositions from the subsystem operating in a desorption cycle back into the system such that potentially flammable gas compositions are purged from the subsystem operating in the desorption cycle at the beginning of the desorption cycle. A heat source is configured to heat contaminants adsorbed in the adsorption/desorption subsystems to remove the contaminants from the adsorption/desorption subsystems in a gaseous state during their respective desorption cycle.

Abstract: A humidity adjusting apparatus includes at least one desiccant linearly reciprocated between a dehumidifying unit and a drying unit, and a motor for driving the desiccant to be moved, thereby improving dehumidifying and humidifying efficiency.

Abstract: A system and method for removal of solvents, or other materials, from an exhaust stream, uses an active adsorption bed and a bed that is periodically regenerated. Electrically heated nitrogen may be used to regenerate the beds. A portion of the exhaust stream to be cleaned is diverted to a heat exchanger, so as to pre-heat the nitrogen used for regeneration. Liquid nitrogen, preferably from the same source as that used to provide gas for regeneration, is directed to the active bed, lowering its temperature and increasing its efficiency. The invention avoids the need for the use of steam to heat the nitrogen, and provides a system that is more efficient than those known in the prior art.

Abstract: A method for desorption and recovery of desorbed compounds, including the steps of generating a recirculating stream of inert gas (1), which passes through the material (2) to be desorbed, heating such inert gas stream to a temperature sufficient to cause the desorption process, yielding a gas effluent (3) from such recirculating stream of inert gas (1) in such a manner that the recirculated gas keeps a constant pressure, cooling such gas effluent to cause condensation of the desorbed compounds contained in such gas effluent (3), the cooling being obtained at least partly by pressure vaporization of a cryogenic fluid (4), and feeding such recirculating gas stream (1) by using at least a part of such pressure vaporized cryogenic fluid that was previously used to cool at least a part of the gas effluent (3).

Abstract: Oxygen generation system having a portable oxygen generator unit including a portable air separation device for the generation of an oxygen-rich gas, a primary gas pump including means to supply air to the portable air separation device, a primary motor to drive the gas pump, a rechargeable power supply to drive the motor, connector means adapted to deliver power to the rechargeable power supply, flow coupling means to transfer the oxygen-rich gas from the portable oxygen generator unit, and a first oxygen-rich gas product discharge port. The system also includes a stationary base unit adapted to couple with the portable oxygen generator unit, wherein the stationary base unit has a stationary power supply system including connector means adapted to recharge the rechargeable power supply in the portable oxygen generator unit, flow coupling means to receive the oxygen-rich gas from the portable oxygen generator unit, and an optional second oxygen-rich gas product discharge port.

Abstract: For PSA or TSA prepurifiers, the temperature rise on adsorption is particularly troublesome when the temperature rise reaches the end of the bed at the end of the adsorption step. This results in an increase in the CO2 and N2O concentration at the end of the cycle. Addition of a regenerator in the middle of the adsorption layer will reduce the temperature rise at the end of the bed and thus enhance the performance of the bed.

Abstract: An evaporative emissions filter for an engine air induction system. The evaporative emissions filter includes a hydrocarbon vapor-adsorbent member disposed within the air induction system. A mechanism is provided for mounting the evaporative emissions filter within the air induction system. Hydrocarbon vapors present in the air induction system after engine shut-down are substantially retained in the adsorbent member until air flows through the air induction system after the engine starts.

Abstract: Using a high pressure rotary adsorbent wheel, a high value compressed gas feed can be purified by concentrating the impurity such as water, condensing it out, before final purification. Instead of exhausting gas from the system, the effluent can be put back into the feed at a point prior to condensation of the high value gas feed, and therefore the entire feed is purified without any high value gas feed going into a waste stream.

Abstract: The invention relates to an adsorber station with a first adsorber (A) and a second adsorber (B). A first closed loop pipeline (1) is connected to the adsorbers (A, B) and is provided with product gas feed line valves (4A, 4B) and regeneration gas discharge line valves (6A, 6B). A second closed loop pipeline (2) that is connected to the adsorbers (A, B) has product gas discharge line valves (7A, 7B) and regeneration gas feed line valves (8A, 8B).

Abstract: A low void pressure swing adsorption system wherein flow movement and pressure pulse are influenced from the same source comprised of at least one hermetically sealed vessel containing an adsorbent bed with an inlet coupled to the adsorbent bed by way of an inlet header and an outlet coupled to the adsorbent bed by way of an outlet header. Void volume of the inlet and outlet headers can be limited to less than 20% of the adsorbent bed volume, preferably to less than 10%, and most preferably to less than 5%, by mounting high pressure source(s) and/or low pressure sink(s) proximate to, or nearly proximate to, the adsorbent bed/vessel. Low void volumes and reduced cycle times may be achieved in all bed configurations, including flat header beds, segmented beds, and vertical beds. Radial beds may be configured so that the void volume of the inlet and outlet headers is less than 50% of the volume of the radial adsorbent bed, preferably to less than 20%, and most preferably to less than 10%.

Abstract: A regenerable filter system includes a flow path along which a stream of fluid flows between an inlet and an outlet. A first filtering unit is located in the flow path. The first filter unit includes first and second regenerable filter beds, wherein each bed has a first adsorbent for removing a first contaminant from the fluid stream. A first valve is located between the inlet and the first and second filter beds for selectively directing the fluid stream through one of the first and the second filter beds. The other of the first and second filter beds is removed from the flow path. A second filtering unit is located in the flow path between the first filtering unit and the outlet. The second filtering unit includes third and fourth regenerable filter beds for removing a second contaminant from the stream of fluid.

Abstract: A method of installing a molecular sieve bed gas enrichment system in a vehicle such as an aircraft. A system controller, a product gas distribution conduit, a high pressure gas supply conduit which extends from a high pressure gas source, and a plurality of molecular sieve beds are installed in the vehicle. Each sieve bed has a first port which delivers product gas through a check valve to an outlet duct. Each sieve bed also includes a second port connected to a valve assembly which is controlled by the system controller to connect the second port either to a gas supply duct during a charging phase or to a venting duct during a venting phase. The outlet duct for each sieve bed is connected to the product gas distribution conduit, and the gas supply duct for each sieve bed is connected to the high pressure gas supply conduit.

Abstract: The present invention relates a method for concentrating a gas by applying a pressure difference to an adsorbent and an apparatus therefor, and particularly, a method for producing an enriched gas in a large amount by introducing a continuous production into every step of the process focusing on productivity rather than concentration of the product gas and an apparatus therefor. The present invention relates to a method incorporating the vacuum swing adsorption method with the pressure swing adsorption method, particularly the rapid pressure swing adsorption method which can continuously produce a desired material in a depressurization step to improve recovery rate of the desired material and productivity and an apparatus therefor. The apparatus according to the present invention is advantageously applied in a small size machine rather than for industrial uses.

Abstract: A method of reducing the sorbate concentration of a process fluid stream using a sorption bed system includes the following steps. A mass of a sorbent material is rotated so that, in a cycle of operation, a given volume of the sorbent mass sequentially passes through first, second, third, fourth, fifth, and sixth zones, before returning to the first zone. A process fluid stream is passed through the sorbent mass in the first zone, and a regeneration fluid stream is passed through the sorbent mass in the fourth zone. A first isolation fluid stream is recycled in a closed loop, independent of the process fluid stream and the regeneration fluid stream, between the sorbent mass in the second zone and in the sixth zone. A second isolation fluid stream, meanwhile, is recycled in a closed loop, independent of the process fluid stream, the regeneration fluid stream, and the first isolation fluid stream, between the sorbent mass in the third zone and in the fifth zone.

Abstract: A rotary module for implementing a high frequency pressure swing adsorption process comprises a stator and a rotor rotatably coupled to the stator. The stator includes a first stator valve surface, a second stator valve surface, a plurality of first function compartments opening into the first stator valve surface, and a plurality of second function compartments opening into the second stator valve surface. The rotor includes a first rotor valve surface in communication with the first stator valve surface, a second rotor valve surface in communication with the second stator valve surface, and a plurality of flow paths for receiving adsorbent material therein.

Abstract: A method of controlling a gas adsorption apparatus including a sieve bed containing molecular sieve bed material, the bed being cyclically operable in a charge mode to adsorb non-product gas from an air supply thereby to increase the concentration of a product gas in a product gas supply which passes to a product gas line and in a vent mode to desorb the adsorbed non-product gas which passes to a non-product gas line, and there being a passage to permit a restricted amount only of the product gas supply to pass from the product gas supply line to the bed when operating in vent mode, and wherein the method includes operating a variable flow device to permit an increased amount of the product gas supply to pass to the bed when operating in vent mode, under predetermined conditions.

Abstract: An adsorber vessel for use in the adsorption of a component from a gas and subsequent regeneration by thermally induced desorption of the component comprises an inlet for regeneration gas having an inlet nozzle containing at least one heater element, and an outlet for regeneration gas, the inlet and outlet for regeneration being separated by a flow path including a flow chamber containing a body of adsorbent, and wherein the body of adsorbent has a first end which is adjacent the inlet for regeneration gas and a second end which is remote from the inlet for regeneration gas, and the or each heater element is located so as not to penetrate through the first end of the body of adsorbent.

Abstract: A portable gas fractionalization apparatus that provides oxygen rich air to patients is provided. The apparatus is compact, lightweight, and low-noise. The components are assembled in a housing that is divided into two compartments. One compartment is maintained at a lower temperature than the other compartment. The lower temperature compartment is configured for mounting components that can be damaged by heat. The higher temperature compartment is configured for mounting heat generating components. An air stream is directed to flow from an ambient air inlet to an air outlet constantly so that there is always a fresh source of cooling air. The apparatus utilizes a PSA unit to produce an oxygen enriched product. The PSA unit incorporates a novel single ended column design in which all flow paths and valves can be co-located on a single integrated manifold. The apparatus also can be used in conjunction with a satellite conserver and a mobility cart.

Abstract: A slide type valve (V) for regulating a gas generating system (10) that has at least a first and a second gas concentrating bed unit (12, 14) includes an outer body (120) with a slide face (106) having at least three open ports (130, 132, 134) communicating with an interior cavity (136) formed in the outer body (120). A vent port (132) and at least two bed ports (130, 134) are adapted to communicate an air flow with a gas concentrating bed unit (12, 14). The vent port (132) is formed between two bed ports. A slide block (100) having an essentially flat face (146) slides along the slide face interior surface (142) of the outer body (12) and has an interior cavity (148) and a first and a second opening (150, 152). The slide block slide face (146) has a closing portion (104) positioned between the first and second openings (150, 152). A controller (C) moves the slide block (100) between a first state (S1) and a second state (S2) for desired air flow.

Abstract: Process in conjunction with the production of oxygen (22), wherein incoming air (10, 16, 16a, 16b,) is brought to pass through a sorbent/zeolite structure (18), which comprises at least three zeolite units (50a–f) intermittently operated in a first stage comprising adsorption of nitrogen from the air and a second stage comprising desorption (20, 20a, 20b) of thus adsorbed nitrogen. At least two of the zeolite units are operated in the adsorption stage, the incoming air being brought to pass consecutively (53a) through the at least two zeolite units to form an increasing nitrogen gradient; and/or at least two units of the zeolite units are operated in the desorption stage, a pressure being released and/or a desorbing gas (22a, 22b) being brought to pass consecutively (53b) through the at least two zeolite units to form a decreasing nitrogen gradient in the zeolite units.

Abstract: A system and a process for recovering high concentrations of methane from crude natural gas and solid waste landfill exhaust gas uses a sequential combination of a pressure swing adsorber unit operation to remove volatile organic compounds from the crude feed gas mixture followed by a membrane separation unit operation. The membrane separation uses a membrane which is selectively gas permeable to reject transmission of methane and thus to produce a permeate depleted in methane relative to the feed mixture. The permeate is also free of volatile organic compounds and is recycled to the pressure swing adsorber unit operation to regenerate saturated adsorbers.

Abstract: A process and an apparatus related to the reduction of the level of a component in a feed gas such as air involving passing the gas to at least three parallel thermal swing adsorption zones charged with an adsorbent and operating according to an adsorption cycle, wherein the cycle of each zone is phased with respect to that of the other zones so that at any point during the cycle, the number of zones in the adsorption step is greater than the number of zones not in the adsorption step.

Abstract: A raised ring encircling a duct at an output port of a desiccant dehumidifier housing prevents its flexible hose from blowing off the duct even when clamped, as dried air blowing pressures through the duct increase.

Abstract: In a method for removing carbon dioxide from the exhaust gas from a gas turbine plant (11), which exhaust gas is subjected to a downstream heat recovery process (12, 33), preferably in the heat recovery steam generator (33) of a water/steam cycle (12), a simplification of the plant engineering is achieved by the fact that the carbon dioxide is removed from the exhaust gas (39) between the gas turbine plant (11) and the heat recovery process (12, 33), and that a rotating, regenerative absorber/desorber (22) is used to remove the carbon dioxide, the absorber side of which absorber/desorber is connected into the exhaust gas stream (39) and the desorber side of which absorber/desorber is connected into a carbon dioxide cycle (38).

Abstract: A gas cabinet assembly for dispensing of gas to a process facility such as a semiconductor manufacturing tool. A purge gas dry scrubber is integrated with the gas flow circuitry and a venturi pump in the gas cabinet. Purge gas is flowed through the flow circuitry in the gas cabinet subsequent to on-stream dispensing of process gas through such flow circuitry, and forms a purge effluent including the residual process gas. The purge effluent is flowed through a dry scrubber unit to sorptively remove the process gas species from the purge effluent. The resultant process gas-depleted purge effluent is vented from the gas cabinet, e.g., into the ducting of the house exhaust system of the process facility. Monitoring of the relative depletion of the dry scrubbing medium in the dry scrubber may be carried out with endpoint detection, e.g., using colorimetric change techniques, toxic gas monitor devices, or PLC/CPU arrangements.

Abstract: Methods and apparatuses for regenerating a NOx adsorber coupled with an exhaust of an engine. An actuator drives a throttle valve to a first position when regeneration of the NOx adsorber is desired. The first position is a position that causes the regeneration of the NOx adsorber. An actuator drives the throttle valve to a second position while regeneration of the NOx adsorber is still desired. The second position being a position that is more open than the first position and operable to regenerate a NOx adsorber.

Abstract: An apparatus for treating compressed air from a rail yard compressed air supply pipeline leading from a central air compressor to outlets at remote locations in a rail yard prior to charging air brake lines of trains with compressed air from the pipeline to prevent contaminants such as moisture, entrained atomized oil and/or particulates such as rust from getting into the air brake line of the train. The apparatus includes an air line, an air inlet connector at one end of the air line, an outlet connector at the other end of the air line, and at least one separator device interposed in the air line between the inlet connector and the outlet connector for separating contaminants from a stream of compressed air passing through the apparatus.

Abstract: An expandable desiccant element for removal of moisture from an air stream. Such expandable desiccant element includes at least one first expandable containment section capable of expanding a first predetermined amount, at least one second expandable containment section capable of expanding a second predetermined amount which is greater than the first predetermined amount connected to the first expandable containment section. Such at least one first expandable containment section and at least one second expandable containment section forming a predetermined shape.

Abstract: A method for the regeneration of humidity-laden drying cartridges includes heating to 220 to 300° C. and introducing it into a drying cartridge for regeneration. Subsequent cooling of the drying cartridge is achieved by a partial stream of air diverted from the dried process air. An arrangement suitable for carrying out the method is also disclosed.

Abstract: A PSA unit for purifying hydrogen in a fuel processor system. The PSA unit employs rotary valves that cycle the pressurization of vessels, including an adsorbent, between a high pressure state and a low pressure state. The purified hydrogen is released from the vessels through a purified gas output port when the vessels are in the high pressure state and the impurities are released through an exhaust port when the vessels are in the low pressure state. The PSA unit also employs a mass flow control device and a pressure sensor in the purified gas output port. A controller receives a pressure signal from the pressure sensor, and controls the flow through the mass flow control device and the speed of the rotary valves so that the proper pressure is maintained at the hydrogen output port.

Abstract: A gas generation method and apparatus, capable of use in an aircraft, generates oxygen with at least one On Board Oxygen Generating System (OBOGS) and generates an inert gas with at least one On Board Inert Gas Generating System (OBIGGS) and selectively supplies an auxiliary supply of inert gas utilizing a waste gas output of the at least one OBOGS. The inert gas can include nitrogen. An auxiliary source of oxygen can also be provided. Control valves can be used to selectively supply the waste gas output of the at least one OBOGS to the atmosphere or to either of two locations. The oxygen can be used in a passenger compartment of the aircraft and the inert gas used in either a fuel tank or cargo bay of the aircraft.

Abstract: A fluid storage and dispensing apparatus including a fluid storage and dispensing vessel having a rectangular parallelepiped shape, and an integrated gas cabinet assembly including such fluid storage and dispensing apparatus and/or a point-of-use ventilation gas scrubber in the vented gas cabinet. By the use of physical adsorbent and chemical sorbent media, the gas cabinet can be enhanced in safety of operation, e.g., where the process gas supplied from the gas cabinet is of a toxic or otherwise hazardous character.

Abstract: Method and apparatus for treating a gas by adsorption. A gas is compressed and then treated by being circulated in an adsorber. A regenerating fluid is indirectly heated by the gas coming from the compressor. In a second regeneration phase, the regenerating fluid is sent directly to the adsorber, while the treated gas is refrigerated by an auxiliary refrigerator.

Abstract: The present invention provides compact adsorption systems that are capable of rapid temperature swings and rapid cycling. Novel methods of thermal swing adsorption and thermally-enhanced pressure swing adsorption are also described. In some aspects of the invention, a gas is passed through the adsorbent thus allowing heat exchangers to be very close to all portions of the adsorbent and utilize less space. In another aspect, the adsorption media is selectively heated, thus reducing energy costs. Methods and systems for gas adsorption/desorption having improved energy efficiency with capability of short cycle times are also described. Advantages of the invention include the ability to use (typically) 30-100 times less adsorbent compared to conventional systems.

Abstract: A regenerable adsorber for removing VOCs from gas streams consists of a porous monolithic carbon which can be regenerated by heating by passing an electric current through it.

Abstract: A method and apparatus for supplying dissolved gases (such as oxygen, ozone, chlorine etc.) for chemical and biological processes is described. The methods and apparatus described are particularly suitable for use in the biodegradation of organic matter (such as in municipal and industrial wastewater treatment), and other uses. The apparatus may comprise a dissolved gas supply system.

Abstract: An apparatus for generating an oxygen enhanced gas by removing nitrogen gas from air, includes a compressor, absorption columns for removing the nitrogen gas from the pressurized air supplied from the compressor, a flow rate measuring device provided downstream of the absorption columns, a manner of measuring ultrasonic oxygen concentration that includes a manner of generating a correction coefficient for a ratio between oxygen and argon gases contained in the oxygen enhanced gas based on the flow rate of the oxygen enhanced gas measured.

Abstract: A method and apparatus for the extraction of water from a gas stream, such as atmospheric air. The method includes contacting the gas stream with a porous adsorbent material having a surface modifying agent adsorbed on the surface of a porous support. The surface modifying agent creates a hydrophilic surface for the adsorption of the water. After the water is adsorbed into the pores, the surface modifying agent is selectively desorbed from the surface. The water then evaporates from the pore and can be collected in a condenser. The method and apparatus of the present invention advantageously operate in a substantially isothermal manner, thereby reducing the size and power consumption of the device. The device can advantageously be used to extract potable drinking water from atmospheric air.

Abstract: A device for enriching air with oxygen by pressure swing adsorption in a molecular sieve bed provides for the separation of water from the air to be enriched with oxygen. The water separator is arranged directly upstream of the molecular sieve bed (8). The water separator is designed as a cyclone type water separator (5).

Abstract: Component contained in a gas mixture can be separated based on a PSA method and recovered with high purities at the same time, the system is simple, the system cost is low, and the operation is easy and may be used for separating oxygen and nitrogen from air or for separating noble gases and nitrogen from a gas mixture containing noble gases and nitrogen, and obtaining each gas as a product.

Abstract: Method and system on board an aircraft for the production of an oxygen-enriched gas stream from an oxygen/nitrogen gas mixture, particularly air, comprising at least one adsorber containing at least one adsorbent for adsorbing at least some of the nitrogen molecules contained in the oxygen/nitrogen feed mixture, characterized in that the adsorbent comprises a faujasite-type zeolite, having a Si/Al ratio of 1 to 1.50, exchanged to at least 80% with lithium cations. Aircraft equipped with such a system, in particular an airliner, especially an airliner of the long-range, large-capacity type.

Abstract: A system for drying a gas, such as air, includes a source of gas to be dried, a multistage compressor having an inlet connected to the source, and a dryer connected interstage to the compressor and to the outlet of the compressor. The dryer is connected interstage to the compressor between a compression stage and a heat exchanger of one of the compressor stages for regenerating a first desiccant filled tower. The dryer is also connected to the outlet of the compressor for drying the gas using a second desiccant filled tower. A communication structure can be activated to connect the first tower to the outlet of the compressor for drying the gas using the first tower, and to connect the second tower interstage to the compressor for regeneration of the second tower.

Abstract: Pressure swing adsorption (PSA) separation of a gas mixture is performed in an apparatus with a plurality of adsorbent beds. The invention provides rotary multiport distributor valves to control the timing sequence of the PSA cycle steps between the beds, with flow controls cooperating with the rotary distributor valves to control the volume rates of gas flows to and from the adsorbent beds in blowdown, purge, equalization and repressurization steps.