Abstract: Embodiments of gas concentrating systems and methods are provided. These systems and methods comprise configuration of hardware and software components to monitor various sensors associated the systems and methods of concentrating gas as described herein. These hardware and software components are further configured to utilize information obtained from sensors throughout the system to perform certain data analysis tasks. Through analysis, the system may, for example, calculate a time to failure for one or more system components, generate alarms to warn a user of pending component failure, modify system settings to improve functionality in differing environmental conditions, modify system operation to conserve energy, and/or determine optimal setting configurations based on sensor feedback.

Abstract: A compressed-air treatment system and operating method are disclosed. The compressed-air treatment system has a first valve unit configured to charge a control line for a compressor with pressure and a pressure regulator valve unit configured to release pressure from a feed line, A control port of the pressure regulator valve unit is connectable to a second valve unit. A regeneration line which has a check valve for regeneration and which is utilized for a regeneration of a dryer cartridge is connected directly to the control line. During a filling operation the compressed-air treatment system is configured to release leakage air of the regeneration check valve via the first valve unit to surroundings. The filling operation is an operating state in which the compressor is activated to perform a supply of compressed air to a vehicle compressed-air system.

Abstract: A regenerative air dryer system including a plurality of air dryer modules, wherein air dryer modules of the plurality of air dryer modules have different air flow rates. A controller selectively operates different combinations of air dryer modules of the plurality of air dryer modules so that a selected combination of air dryer modules has a combined air flow rate based on system air flow requirements.

Abstract: A method and system for removing carbon dioxide from flue gas emitted by a fossil fuel operated power plant. In the method and system, carbon dioxide is removed from the flue gas by an absorption process using a scrubbing liquid. The charged scrubbing liquid is regenerated in a desorption process. At least some of the energy required for the regeneration process is fed using low-pressure steam that is withdrawn from the steam-water circuit of the power plant before entering a low-pressure steam turbine. The low-pressure steam is fed to an intermediate steam turbine. The low-pressure steam is expanded to a discharge pressure of less than 3.5 bar and is then fed to the desorption process. The pressure for the desorption process is adjusted by a regulation device in accordance with the discharge pressure from the intermediate steam turbine.

Abstract: A regeneration controller for an air dryer on a vehicle includes a location identifier that determines a current location, a regeneration profile identifier that selects a regeneration profile based on the current location, and a regeneration initiator that initiates regenerations of the air dryer based on the regeneration profile.

Abstract: Provided is an ozone concentrator including an ozone generator (3), adsorption/desorption columns (4) in which silica gel (6) cooled with a certain-temperature refrigerant (25) for concentrating ozone generated by the ozone generator (3) is packed, a refrigerating machine (23) for cooling the refrigerant (25), a vacuum pump (20) for enhancing a concentration of the ozone in one of the adsorption/desorption columns (4) by discharging mainly oxygen from the silica gel (6) adsorbing the ozone, a plurality of valves (8) to (13) for air pressure operations, for switching passages of gas that is allowed to flow in or flow out with respect to the adsorption/desorption columns (4), and ozone concentration meters (28, 29) for measuring the concentration of the ozone enhanced by the vacuum pump (20), in which a discharge line of the vacuum pump (20) is connected to another one of the adsorption/desorption columns (4), whereby the ozone is allowed to pass through another one of the adsorption/desorption columns again.

Abstract: Systems and methods for processing high purity materials are disclosed. A unit operation processes a material stream, an operational parameter of the unit operation is monitored, and a standby unit is charged with pressurized gas to achieve system pressure. The material stream is diverted to the standby unit in response to the operational parameter of the unit operation registering a threshold value. Flow exiting the standby unit is first vented via an outlet, and then directed toward a point of use after the pressurized gas has been purged. The unit operation may then be serviced and subsequently brought back online. A second unit operation may process a second material stream simultaneously, and the second material stream may be periodically diverted to the standby unit in like manner, thus reducing line pressure variation. The disclosed method may be performed manually or implemented automatically through use of a controller.

Abstract: Disclosed is a harmful material treatment system for recovering the energy and removing the harmful material in the process of treating the gas containing the harmful material generated in the multiplex utilization facility, in the display mall, in diverse manufacturing processes and in the vehicle painting process, more particularly, to a harmful material treatment system which can recover the energy contained in the air conditioning facility or in the exhaust gas of the process with an efficiency of more than 90%, for exhausting the inside air to the outside so as to treat the contaminating material such as odor and volatile organic chemicals, and to remove the harmful material with a removal efficiency of more than 90% by adsorbing and concentrating the harmful material with a rotary-type adsorbent.

Abstract: Apparatus, process and article for treating a gas containing one or more of a chemical and/or biological contaminant. The process includes contacting the gas with an aggregate composition comprising an insoluble rare earth-containing compound to form a gas depleted of chemical and active biological contaminants. The insoluble rare earth-containing compound can include one or more of cerium, lanthanum, or praseodymium. The composition comprises no more than two elements selected from the group consisting of yttrium, scandium, and europium when the aggregate has been sintered. A suitable insoluble cerium-containing compound can be derived from cerium carbonate. In one embodiment, the aggregate composition consists essentially of one or more cerium oxides, and optionally, a binder. Although intended for a variety of fluid treatment applications, such applications specifically include the treatment of breathing gases such as air that may contain chemical and/or biological contaminants.

Abstract: A method for purifying or separating a gas mixture comprising at least one fuel, using a unit having at least one adsorber subjected to a pressure cycle comprising at least one step of placing under vacuum by means of a vacuum pump, wherein at least one adsorber and/or the vacuum pump, depressurized during the cycle, is repressurized at least partly by an external gas to said unit and not containing a sufficient quantity of oxidizer to create an inflammable mixture during this repressurization.

Abstract: A system and a method are described for monitoring pressure imbalances in the adsorbent beds of a portable gas concentrator. Using the programmability features found in modern portable concentrators, various mitigative procedures to adjust for pressure imbalances and to predict the need for service are disclosed.

Abstract: An arrangement for generating oxygen in a facility is described, which arrangement has at least one unit for generating medical air (V, R), a vacuum system (VS), and a PSA unit (A), which serves to generate an oxygen product stream. According to the invention, the PSA unit (A) and the vacuum system (VS) are interconnected in such a way that the adsorber or adsorbers of the PSA unit (A) can be regenerated by means of the vacuum system (VS), and/or the unit for generating medical air (V, R) is connected to the PSA unit (A) in such a way that at least a subsidiary stream (2) of the generated medical air is delivered as feed gas to the PSA unit (A).

Abstract: A system and a method are described for monitoring pressure imbalances in the adsorbent beds of a portable gas concentrator. Using the programmability features found in modern portable concentrators, various mitigative procedures to adjust for pressure imbalances and to predict the need for service are disclosed.

Abstract: Systems and methods for processing high purity materials are disclosed. A unit operation processes a material stream, an operational parameter of the unit operation is monitored, and a standby unit is charged with pressurized gas to achieve system pressure. The material stream is diverted to the standby unit in response to the operational parameter of the unit operation registering a threshold value. Flow exiting the standby unit is first vented via an outlet, and then directed toward a point of use after the pressurized gas has been purged. The unit operation may then be serviced and subsequently brought back online. A second unit operation may process a second material stream simultaneously, and the second material stream may be periodically diverted to the standby unit in like manner, thus reducing line pressure variation. The disclosed method may be performed manually or implemented automatically through use of a controller.

Abstract: Ice-clad machinery and equipment in very cold environments are made more easily recoverable by enclosing the machinery and equipment in an environmentally contained area and introducing desiccant dehumidified air into the contained area to lower the vapor pressure in fostering a “sublimation” process conversion from the solid state of the ice to a gaseous state which can be exhausted without first going through any intermediate liquid state.

Abstract: An exhaust gas purifying apparatus for a diesel engine has a filter provided in an exhaust pipe of the engine for trapping diesel particulates contained in exhaust gas. The filter is re-generated when an accumulated amount of the diesel particulates exceeds a predetermined value. An electronic control unit estimates the accumulated amount of the diesel particulates from a pressure loss at the filter, based on an accumulation characteristic in which the pressure loss is related to the accumulated amount of the diesel particulates, and corrects the accumulation characteristic depending on flow velocity of the exhaust gas.

Abstract: A method for purifying or separating a gas mixture comprising at least one fuel, using a unit having at least one adsorber subjected to a pressure cycle comprising at least one step of placing under vacuum by means of a vacuum pump, wherein at least one adsorber and/or the vacuum pump, depressurized during the cycle, is repressurized at least partly by an external gas to said unit and not containing a sufficient quantity of oxidizer to create an inflammable mixture during this repressurization.

Abstract: A method of purifying or separating a gas using a number of adsorbers on phase-shifted cycles, and more particularly to the purification of atmospheric air, prior to cryogenic separation of the said air by cryogenic distillation is provided. More specifically still, it relates to the purification of air with a TSA cycle using radial adsorbers.

Abstract: There are provided a nanowire filter, a method for manufacturing the same, a filtering apparatus having the same, and a method for removing material adsorbed on the nanowire filter. The filtering apparatus includes: a filter having a supporting member and a plurality of nanowires supported on the supporting member and arranged in a crystallized state; and a body into which the filter is inserted and secured, and which has an inlet for guiding an introduced fluid to the filter and an outlet for discharging the fluid filtered through the filter to the outside.

Abstract: A method for controlling an adsorption unit and associated compressor that adjusts the flow rate of a compressed feed stream produced by the compressor so that it increases from a nominal flow rate and then decreased back to the nominal flow rate. The increase and decrease of the feed stream flow rate are controlled in accordance with increase and decrease rate functions of adsorbent bed pressure ratio between off-line and on-line adsorbent beds and a triggering pressure ratio at which the feed flow rate decreases. Each of the increase and decrease rate functions is tuned to produce a similar response in the flow of a product stream produced by the adsorption unit. Additionally, repressurization time is controlled by driving it toward a target value that allows the purge stage of regeneration to be maximized and therefore, the degree to which each of the adsorbent beds is regenerated.

Abstract: A vacuum pressure swing absorption (VPSA) system and a four-cycle method are provided for separating and concentrating one portion of a gas mixture. A reciprocating piston (6) and associated valves and conduits can be combined with a bed of selective porous absorbent material (2) to produce concentrated oxygen from ambient air. The piston and valves are arranged to induct a feed gas mixture, produce product gas at a specified output pressure, regenerate the porous absorbent material, and expel depleted gas. Such an arrangement can result in higher energy efficiency as compared to conventional processes since free expansion losses are substantially avoided. The product gas flow can be adjusted to meet demand while maintaining high energy efficiency.

Abstract: The invention relates to a method for dehumidifying air and to an air dehumidifier. To this end, a filter element is provided that is filled with granular material that can be regenerated by baking out. For effecting this baking out, a heating device is provided that is only actuated when both a humidity sensor indicates that a humidity limit value has been exceeded as well as a relative pressure sensor or a comparable technical means indicates that, at the moment, no flow toward the oil expansion tank is recorded.

Abstract: A method and an arrangement are provided for purifying gases which are fed to a fuel cell for operation. A filter system, which is designed to separate out particulates and polluting gases, is arranged in a feed passage for the respective gas.

Abstract: A fuel cell power generation system, equipped with a fuel reforming device and a fuel cell body, includes valves, pipelines, a condenser, and a pump for feeding a burner exhaust gas (raw gas) discharged from a heating burner of the fuel reforming device into the fuel reforming device, and an inert gas formation device including an oxidizable and reducible oxygen adsorbent, which is disposed in the pipelines, and adsorbs oxygen in the burner exhaust gas to remove oxygen from the burner exhaust gas and form an inert gas. The fuel cell power generation system can reliably remove residual matter, without leaving it within the fuel reforming device, in a simple manner at a low cost and with a compact configuration.

Abstract: A particulate filter assembly includes an electrode assembly, a particulate filter positioned in an electrode gap defined between two electrodes of the electrode assembly, a power supply electrically coupled to the electrode assembly, and a controller for controlling operation of the power supply to apply a regenerate-filter signal to the electrode assembly to oxidize particulates collected by the particulate filter. An associated method of regenerating the particulate filter is disclosed.

Abstract: A method to desorb water from a desiccant of an air recharge system comprises the steps of a) filling a purge reservoir using an air compressor and a desiccant dryer to produce discharge air, b) stopping the air compressor; c) back purging the desiccant, and d) vent resetting the system, wherein the filling a purge reservoir step does not result in an addition of discharge air to an air storage tank in fluid communication with the purge reservoir and wherein the air storage tank is filled with an amount of the discharge air such that the air storage tank is at a full storage tank pressure prior to filling the purge reservoir. A method of filling an air storage tank of an air recharge system is also disclosed.

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: 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 process and system for purifying an impure gas to produce a purified gas in a gas purification system and protecting the system from damage by a) passing a portion of a first gas stream into a reactor vessel, which exits as a second purified gas stream; b) combining a portion of the second purified gas stream with another portion of the first gas stream to form a combined gas stream; and c) passing the combined gas stream into a sensing device to regulate the flow of the first and second gas streams into the reactor vessel.

Abstract: System for removal of targeted pollutants, such as oxides of sulfur, oxides of nitrogen, mercury compounds and ash, from combustion and other industrial process gases and processes utilizing the system. Oxides of manganese are utilized as the primary sorbent in the system for removal or capture of pollutants. The oxides of manganese are introduced from feeders into reaction zones of the system where they are contacted with a gas from which pollutants are to be removed. With respect to pollutant removal, the sorbent may interact with a pollutant as a catalyst, reactant, adsorbent or absorbent. Removal may occur in single-stage, dual-stage, or multi-stage systems with a variety of different configurations and reaction zones, e.g., bag house, cyclones, fluidized beds, and the like. Process parameters, particularly system differential pressure, are controlled by electronic controls to maintain minimal system differential pressure, and to monitor and adjust pollutant removal efficiencies.

Abstract: The invention relates to a method and an apparatus for cleaning ambient air of a vehicular adsorption unit (8). The vehicle includes a combustion engine (1) and a passenger ventilation system (5, 6, 7, 8, 9, 10, 11). Adsorption takes place whether the engine (1) is running or not. During adsorption, a fan (11) forces ambient air from an inlet (6) to the ventilation system in a first direction, through an adsorption unit (8), and out of an outlet (10). To desorb when the engine is running, air is supplied to a heater (13). Heated air passes through the adsorption unit (8) to release pollutants and regenerate the unit. Pollutant-containing air passes through a second heater (4,16) and then through the first heater (13) to heat the ambient air. Finally, polluted air is drawn from the heat exchanger (13) to an intake conduit (3) of the engine (1).

Abstract: System for removal of targeted pollutants, such as oxides of sulfur, oxides of nitrogen, mercury compounds and ash, from combustion and other industrial process gases and processes utilizing the system. Oxides of manganese are utilized as the primary sorbent in the system for removal or capture of pollutants. The oxides of manganese are introduced from feeders into reaction zones of the system where they are contacted with a gas from which pollutants are to be removed. With respect to pollutant removal, the sorbent may interact with a pollutant as a catalyst, reactant, adsorbent or absorbent. Removal may occur in single-stage, dual-stage, or multi-stage systems with a variety of different configurations and reaction zones, e.g., bag house, cyclones, fluidized beds, and the like. Process parameters, particularly system differential pressure, are controlled by electronic controls to maintain minimal system differential pressure, and to monitor and adjust pollutant removal efficiencies.

Abstract: A method of controlling a plant for processing a gas by adsorption, with N adsorbers R1 to R0 and variable N phase times. The method utilizes a mobile parameter for identifying the operating state of N adsorber which is in each successive phase time of the cycle. For a given phase time, a parameterized sequence (S, S′) of control steps for the plant are defined. A control sequencer of the plant is generated by matching an adsorber (R1 to R0) with each mobile parameter of the parameterized sequence during each phase time of the cycle, causing the succession of phase times of the cycle to be followed at all the adsorbers in operation.

Abstract: An oxygen concentrator system with altitude compensation includes at least one oxygen concentrator sub-system and a plenum subsystem. The at least one oxygen concentrator sub-system produces oxygen enriched product which is outputted to both the oxygen concentrator system output and to a plenum chamber within the plenum subsystem. The plenum chamber is trickle charged with the oxygen enriched product when the at least one oxygen concentrator sub-system produces an excess amount of oxygen enriched product. Should the demand for oxygen enriched product exceed the capability of the at least one oxygen concentrator sub-system, additional oxygen enriched product is provided by the plenum chamber until such time that the capability of the at least one oxygen concentrator sub-system exceeds the demand for oxygen enriched product. At that time, oxygen enriched product is no longer provided by the plenum chamber but rather the plenum chamber is again trickle charged.

Abstract: An oxygen concentrator system with altitude compensation includes at least one oxygen concentrator sub-system and a plenum subsystem. The at least one oxygen concentrator sub-system produces oxygen-enriched air which is outputted to both the oxygen concentrator system output and to a plenum chamber within the plenum subsystem. The plenum chamber is trickle charged with the oxygen-enriched air when the at least one oxygen concentrator sub-system produces an excess amount of oxygen-enriched air. Should the demand for oxygen-enriched air exceed the capability of the at least one oxygen concentrator sub-system, additional oxygen-enriched air is provided by the plenum chamber until such time that the capability of the at least one oxygen concentrator sub-system exceeds the demand for oxygen-enriched air. At that time, oxygen-enriched air is no longer provided by the plenum chamber, but rather the plenum chamber is again trickle charged.

Abstract: A continuous flow dryer system for compressed air includes first and second air dryers for receiving and alternately drying compressed air from a source. The dried air from the first dryer is transmitted to the second dryer. First and second reservoirs store the dried compressed air. A plurality of control valves in the second air dryer are used for distributing the dried air to the respective reservoirs.

Abstract: A continuous flow dryer system for compressed air includes first and second air dryers for receiving and alternately drying compressed air from a source. The dried air from the first dryer is transmitted to the second dryer. First and second reservoirs store the dried compressed air. A plurality of control valves in the second air dryer are used for distributing the dried air to the respective reservoirs.

Abstract: System for removal of targeted pollutants, such as oxides of sulfur, oxides of nitrogen, mercury compounds and ash, from combustion and other industrial process gases and processes utilizing the system. Oxides of manganese are utilized as the primary sorbent in the system for removal or capture of pollutants. The oxides of manganese are introduced from feeders into reaction zones of the system where they are contacted with a gas from which pollutants are to be removed. With respect to pollutant removal, the sorbent may interact with a pollutant as a catalyst, reactant, adsorbent or absorbent. Removal may occur in single-stage, dual-stage, or multi-stage systems with a variety of different configurations and reaction zones, e.g., bag house, cyclones, fluidized beds, and the like. Process parameters, particularly system differential pressure, are controlled by electronic controls to maintain minimal system differential pressure, and to monitor and adjust pollutant removal efficiencies.

Abstract: A component gas concentrator includes an air compressor, an air-tight first container containing a molecular sieve bed, the first container in fluid communication with the compressor through a first gas conduit, and an air-tight second container in fluid communication with the first container through a second gas conduit. A gas flow controller such as PLC controls actuation of valves mounted to the gas conduits.

Abstract: A component gas concentrator includes an air compressor/vacuum pump, an air-tight first container containing a molecular sieve bed, the first container in fluid communication with the compressor/vacuum pump through a first gas conduit, and an air-tight second container in fluid communication with the first container through a second gas conduit. A gas flow controller such as PLC controls actuation of valves mounted to the gas conduits.

Abstract: A vapor recovery system for a fuel storage tank. The system includes a pair of VOC adsorbent canisters that alternately recover VOC vapors from the fuel tank ullage or are regenerated. Regeneration of the VOC adsorbent canisters is provided by exhausting the VOC vapors from the VOC canisters using a vacuum pump and back into the fuel tank ullage. When the operating pressure of the fuel tank ullage is elevated, an auxiliary VOC adsorbent canister is operated in parallel with the pair of canisters in order to recover the increased amount of VOC vapors in the tank ullage.

Abstract: A regenerable air cleaning device is disclosed which comprises a filter holder supporting a regenerable filter that includes activated carbon fibers (ACF) and a control system that is adapted to determine when to regenerate the regenerable filter. The device exhibits high performance and longevity over many regeneration cycles.

Abstract: A process and a system for purifying gas, such as air, before cryogenic distillation, in which at least one energy parameter, chosen from the flow rate of the regeneration gas entering and/or leaving at least one adsorber, the duration of the regeneration step and the regeneration temperature of the regeneration gas entering at least one adsorber, is controlled, modified and/or regulated depending on at least one operating condition chosen from the pressure of the gas to be purified entering and/or leaving at least one adsorber, the flow rate of the gas to be purified entering and/or leaving at least one adsorber, the temperature (Ta) of the gas to be purified entering at least one adsorber and the content of impurities contained in the gas to be purified entering at least one adsorber and depending on the thermal profile of the heat front output by at least one adsorber at the end of regeneration.

Abstract: Device and method for the regeneration of a drying agent in compressed air system. The wetting degree of the drying agent is estimated and recorded by a control unit. The control unit ensures that the drying agent is dehumidified as soon as the wetting degree has reached a certain wetting degree. This certain wetting degree may be set to different levels for different operational condition.

Abstract: A control device for molecular sieve on-board oxygen generating systems measures both temperature and pressure of the inlet air of an oxygen generating system. An electronic control unit applies pressure limits to a pressure measurement signal and combines it with a temperature measurement signal to produce a composite analog signal responsive to both temperature and pressure inlet air conditions. This analog signal is linearly converted to a frequency signal, whereupon the frequency signal is divided by a constant in order to produce a drive signal for control of the absorb/vent bed cycle valves. Composition control is achieved by venting product mixture as required. Inlet air pressures down to 5 PSIG (pounds per square inch gauge) produce correct system operation, and the quantity of conditioned air required is automatically limited so that system efficiency is higher than prior art systems.

Abstract: A pressure swing adsorber (PSA) air prepurifier includes at least a first adsorber and a second adsorber and a controller for controlling air feed to the first adsorber and the second adsorber. The invention is a "realtime" method for controlling cycle times for each adsorber and includes the following steps. During a determined time period, flow is measured to an adsorber that is coupled to an air inlet. An actual totalized flow to the on-line adsorber is accumulated, based upon the measured flow values. During this time, air feed conditions (e.g., temperature, pressure, relative humidity) are monitored and periodically, a maximum totalized flow to the adsorber is calculated, determined, at least in part, based upon the monitored air feed conditions.

Abstract: An alternating pressure apparatus for obtaining oxygen from the air has two adsorbers to which an air blower for adsorption air and a vacuum pump stand for desorption are connected. The vacuum pump stand has two vacuum pumps in tandem. In a partial load operation characterized by low O.sub.2 removal; and during the lower pressure equalization of the adsorbers, the vacuum pump stand is connected to the air blower in that in each case the vacuum valve, connecting one adsorber to the vacuum pump stand, and the air valve, connecting the same adsorber to the air blower, are opened at the same time.

Abstract: An alternating pressure apparatus for obtaining oxygen from the air has two adsorbers to which an air blower for adsorption air and a vacuum pump stand for desorption are connected. The vacuum pump stand has two vacuum pumps in tandem. The second vacuum pump in the direction of flow is configured as a rotary piston pump with preliminary inlet cooling for the defined inflow of outside air at atmospheric pressure. The inlet of the second vacuum pump is connected to the outlet of the first vacuum pump without the use of gas cooling by water injection or by a heat exchanger. The alternating pressure apparatus operates with a desorption pressure between 300 mbar and 500 mbar.

Abstract: An acoustic oxygen sensor is provided which can be used in the output lines leading from the sieve beds. This sensor can be used in communication with a microprocessor to control the production and evacuation cycles of the sieve beds, i.e., for example to determine the period for which a bed is supplied with compressed air and communicates with the reservoir as well as to determine the pressure of the compressed air and to determine the amount of time that the product gas is fed through the flow equalization path to supply an aliquot of purging gas to a used bed. In the feedback loop, the microprocessor utilizes the measured oxygen concentration and flow rate to optimize the settings necessary to achieve maximum oxygen concentration and flow rate efficiency. Since the microprocessor has the ability to make incremental changes and compare relative values, the optimum values can be determined empirically eliminating the need to perform complex theoretical calculations.