Abstract: 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.

Abstract: A battery retaining system for a portable oxygen concentrator includes a first rail configured to receive a first slide of a battery, a second rail configured to receive a second slide of the battery, the second rail being spaced apart from the first rail so as to form a channel configured to receive the battery, and a flexible stiffening mechanism configured to impart a biasing force on a surface of the battery when the battery is received within the channel. The flexible stiffening mechanism includes a protrusion projecting from the first rail at least partially towards the second rail and a slit positioned behind the protrusion and configured to facilitate travel of the protrusion fore and aft.

Abstract: Apparatus for transforming the air exchange load of a higher air exchange rate space into the air exchange load of a lower air exchange rate space, including: a housing; an air inlet and at least one air outlet formed in the housing; a passageway extending through the housing and connecting the air inlet to the at least one air outlet; a circulation fan disposed in the passageway so as to draw the air of the higher air exchange rate space into the air inlet, through the passageway, and return that air to the higher air exchange rate space through the at least one air outlet; and a filter disposed in the passageway for purging noxious substances from the air passing through the passageway, whereby to transform the air exchange load of a higher air exchange rate space into the air exchange load of a lower air exchange rate space.

Abstract: A system and method recover water from an ambient airstream. Dehumidification of the airstream is also achieved by removal of the water. A device of the system includes a chamber having a group of trays that hold respective amounts of liquid desiccant in each tray. A foam media absorbs the desiccant to increase an exposed surface of the desiccant to the airstream. Fans and valves are used to control airflow through the device. A charge cycle circulates air through the device to remove water vapor from the airstream. A subsequent extraction cycle removes water collected in the liquid desiccant by a condenser communicating with the chamber. An integral heat exchanger adds heat to the chamber during the extraction cycle. A controller is used to integrate and manage all system functions and input variables to achieve a high efficiency of operational energy use for water collection.

Abstract: Apparatus and methods are disclosed that allow for the monitoring and analysis of production process data for a multi-step asynchronous cyclic production process (e.g. pressure swing adsorption) in a steady state plant (such as a steam methane reforming plant). Data collected from cooperating sensors is processed applying a moving window discrete Fourier transform (DFT). The transformed data can be further analyzed in the broader steady-state plant environment to accurately detect any process anomalies and avoid false alarms.

Abstract: Embodiments of multi-stage air filtration systems are disclosed herein. A filtration system configured in accordance with one embodiment includes at least a first filter and a second filter arranged in series in an exhaust stream. The first filter is arranged to hold a first active media in the exhaust stream, the second filter is arranged to hold a second active media in the exhaust stream, and the active media is selected to remove one or more contaminants known to be in the exhaust stream. The system also includes at least one sensor arranged to detect the presence of the one or more contaminants downstream of the first filter and/or the second filter.

Abstract: Active carbon filters and systems that are operative to detect active carbon filter degradations are provided. The active carbon filter can include a carbon filter comprising activated carbon and defining a filter surface; a first piezoelectric wafer active sensor on the filter surface that is electrically isolated from the carbon filter; and a second piezoelectric wafer active sensor on the filter surface that is electrically connected to the filter surface; and an impedance monitoring device electrically connected to the first piezoelectric wafer active sensor and the second piezoelectric wafer active sensor. Methods are also disclosed for determining if any degradation has occurred in an active carbon filter.

Abstract: Apparatus and methods are disclosed that allow for the monitoring and analysis of production process data for a multi-step asynchronous cyclic production process (e.g. pressure swing adsorption) in a steady state plant (such as a steam methane reforming plant). Data collected from cooperating sensors is processed applying a moving window discrete Fourier transform (DFT). The transformed data can be further analyzed in the broader steady-state plant environment to accurately detect any process anomalies and avoid false alarms.

Abstract: A Pressure Swing Adsorption filtration that separates a first set of particles and a second set of particles to produce a purified gas output can be monitored in real-time. A sentinel component can provide real-time in situ tracking of a parameter associated with the PSA filtration and dynamically adjusts the PSA filtration based upon the real-time tracked parameter. The real-time monitoring of the parameter further enables maintenance of equipment utilized with the PSA filtration as well as equipment down-the-line that utilize the purified gas output.

Abstract: A portable oxygen concentrator designed for medical use where the usable life of the sieve beds, adsorbers, is monitored and communicated to the user or service provider through a user interface or a transmitted signal. The concentrator is designed so that the beds are easily replaced by the user or a field technician. Preferably PSA cycle operating parameters appropriate to the replaced beds can be easily reset if needed by the user or service provider.

Abstract: An air dehydrator system for supplying a source of dehydrated air includes an offsite data management system; at least one data network; and an air dehydrator located remote from the offsite data management system. The dehydrator includes a housing containing at least one drying canister; a pressurized air source; and a control circuit coupled with the pressurized air source. The control circuit is also in communication via the at least one data network with the offsite data management system. The control circuit controls operation of the pressurized air source dependent upon control by the offsite data management system.

Abstract: An integrated system [1000] is described for reducing operating costs of power plants while keeping gaseous pollutants in exhaust flue gasses, such as Mercury (Hg), below acceptable limits. Controller [1800] monitors and controls operation of a scrubber [1300], activator injection system [1400], sorbent injection system [1500] and a filter [1600]. Scrubber [1300] provides a neutralizer to remove SO2 emissions. Activator injection system [1400] provides and activator that increases affinity of the pollutant gasses for a sorbent. Sorbent injection system [1500] employs novel low friction injection lances [1590] that evenly distribute the sorbent particles. A filter [1600] collects the sorbent particles that cake onto filter bags [1620] that are periodically cleaned. A controller [1800] receives the costs of materials consumed and the filter bag life for the plant and performs an optimization of the multiple variables to minimize costs while keeping the pollutant emissions below a prescribed limit.

Abstract: A real-time monitoring system that monitors various aspects of the operation of a refrigerant-cycle system is described. In one embodiment, the system includes a processor that measures power provided to the refrigerant-cycle system and that gathers data from one or more sensors and uses the sensor data to calculate a figure of merit related to the efficiency of the system. In one embodiment, the sensors include one or more of the following sensors: a suction line temperature sensor, a suction line pressure sensor, a suction line flow sensor, a hot gas line temperature sensor, a hot gas line pressure sensor, a hot gas line flow sensor, a liquid line temperature sensor, a liquid line pressure sensor, a liquid line flow sensor. In one embodiment, the sensors include one or more of an evaporator air temperature input sensor, an evaporator air temperature output sensor, an evaporator air flow sensor, an evaporator air humidity sensor, and a differential pressure sensor.

Abstract: A FET gas sensor having a relatively low operating temperature, for example, room temperature, is free from cross sensitivities from interfering gases by a preceding in-line filter. The sensor's service life is substantially stabilizable by using fabric-like activated charcoal filters which can be regenerated by a moderate temperature increase, and by limiting the diffusion of the analyte gas, which is made possible by the relatively small amount of gas detectable on the sensitive layer of the sensor. This substantially increases the service life of the filters. The gas sensor eliminates cross sensitivities to thereby increase the detection reliability thereof. Also, the gas sensor has relative long term stability and is economical to build. The gas sensor can read relatively weak signals generated by gas-sensitive layers, for example, without other stronger gas signals interfering with the weak signals.

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 compressor system which includes the use of free piston linear compressors so as to reduce power consumption, noise and vibration reduction.

Abstract: A method is provided for indicating the useful service life of a gas filtration and purification system comprising steps of embedding two or more mass-responsive electronic sensors (e.g., surface acoustic wave devices) in a sorbent bed of a filtration cartridge, wherein the mass-responsive electronic sensors are coated with a non-conductive absorptive organic polymer; passing a gas containing a volatile chemical of interest through the filtration cartridge and in contact with the two mass-responsive electronic sensors; and measuring a difference in an electronic property between the two mass-responsive electronic sensors. In such a manner, the two mass-responsive electronic sensors act as internal references with respect to each other, thereby eliminating variations in temperature, interferents, pressure, and the like.

Abstract: A method for determining a service life for a filter includes measuring exposure data and calculating a service life estimate based on the exposure data. The service life estimate is representative of an estimated exposure time that the filter is exposed to ambient conditions represented by the exposure data before the contaminant passes through the filter at a breakthrough concentration. The method also includes obtaining environmental data and establishing a predicted service life based on the environmental data. The predicted service life is representative of a predicted exposure time that the filter is exposed to the ambient conditions represented by the environmental data before the contaminant passes through the filter at the breakthrough concentration. The method further includes determining the service life for the filter based on a comparison of the estimated and predicted service lives.

Abstract: A method is provided for indicating the useful service life of a gas filtration and purification system comprising steps of embedding two or more mass-responsive electronic sensors (e.g., surface acoustic wave devices) in a sorbent bed of a filtration cartridge, wherein the mass-responsive electronic sensors are coated with a non-conductive absorptive organic polymer; passing a gas containing a volatile chemical of interest through the filtration cartridge and in contact with the two mass-responsive electronic sensors; and measuring a difference in an electronic property between the two mass-responsive electronic sensors. In such a manner, the two mass-responsive electronic sensors act as internal references with respect to each other, thereby eliminating variations in temperature, interferents, pressure, and the like.

Abstract: The present invention relates to a high capacity gas filter system. The metal filter of the system includes a visible indicator which indicates when the filter is spent. The indicator is preferably a non-reactive glass tube with indicator material therein. The glass tube can be protected to maintain gas flow integrity in case the glass tube breaks. The filter is attachable to or removable from its connecting base using a cooperating threaded knob and threaded bolt such that the filter is pulled tightly onto the base and forced off of the base depending on how the knob is rotated.

Abstract: An electronic controller (16) controls the operation of an electrochemical oxygen generating system (14) producing a desired gas. The product gas is fed to a storage unit (12) or a regulator (28) and pulsing valve (28) controlling the gas flow to a user. A two-stage system (180) combines a low pressure 100 and a high pressure (150) gas generating subsystems. The low pressure subsystem (100) uses IMAT's (106) to pump oxygen from ambient air to generate a low-pressure. The high pressure subsystem (150) uses IMAT's (160) to pump oxygen to high-pressure oxygen storage devices (194).

Abstract: A continuous concentration system for volatile organic compounds for concentrating volatile organic compounds that undergo an absorption process and a removal process includes: a moving-bed chamber in which modules for absorbing volatile organic compounds are absorbed. An absorption bed line to which the volatile organic compounds are supplied to be absorbed to the module is provided on one side of the moving-bed chamber. A removal-cooling bed line for performing a removal process for removing the volatile organic compounds absorbed to the module and a cooling process for cooling the module that has undergone the removal process is provided on the other side of the moving-bed chamber.

Abstract: A mechanical device is used to estimate a service life of an air filter exposed to a certain chemical at various concentrations, flow rates, and relative humidity conditions. The device includes two members, one of which has at least one window, connected so that their surfaces are movable relative to one another. One member has numerical values for chemical concentrations and service life estimates printed on it. The member having windows has at least one mark printed on it by which it can be oriented relative to the chemical concentration scale on the other member. When the two members are aligned relative to a chemical concentration of interest, the corresponding service life estimate is displayed in an appropriate window.

Abstract: An active adsorbent pollutant reducing system includes a canister containing activated carbon, a pump and a series of valves connected to the canister and the pump. The valves and pump of the system are controlled so that vapor/air in the ullage of a gasoline storage tank is pumped to the canister/adsorbent material when tank pressure reaches a first level with vapor being adsorbed and air being discharged to atmosphere. When a second tank pressure level, lower than the first tank pressure level, is achieved, the valves are controlled to reconfigure the pump and canister so that continued pump operation pulls a vacuum on the canister resulting in adsorbed gasoline vapor being purged from the adsorbent material and returned to the storage tank. Tank pressure, HC content in the vapor flow and canister weight can be used for control of the system.

Abstract: Methods and apparatuses for determining the condition of a pneumatic system air dryer are provided. An output of the pneumatic valve or of a conduit interconnected to the outlet of the pneumatic valve is positioned such that a discharge passed through the pneumatic valve while the valve is open is in view of an operator and/or is directed to a moisture sensor. Moreover, the discharge and/or an output device interconnected to the moisture sensor is in view of the operator while the operator is in a position to operate the pneumatic valve. An observation volume with a sight glass or window and/or a moisture sensor can be provided to facilitate the observation or detection of moisture or oil in the discharge.

Abstract: A bypass factor of an evaporator is used to indicate when an air filter of an HVAC is clogged. The bypass factor represents the amount of air that is bypassed without direct contact with the evaporator. As the air filter clogs, the bypass factor decreases. The bypass factor can also be used for early detection of clogging of the air filter. A first bypass factor is calculated by using the temperature measurements, and a second bypass factor is calculated by using the airflow rate of the air. The difference between the two bypass factors determines the error. An increase in the error indicates that the air filter is clogged. A coefficient of performance of the evaporator can also be calculated to detect if the air filter is clogged. A decrease in the coefficient of performance indicates that the air filter is clogged.

Abstract: A real-time monitoring system that monitors various aspects of the operation of a refrigerant-cycle system is described. In one embodiment, the system includes a processor that measures power provided to the refrigerant-cycle system and that gathers data from one or more sensors and uses the sensor data to calculate a figure of merit related to the efficiency of the system. In one embodiment, the sensors include one or more of the following sensors: a suction line temperature sensor, a suction line pressure sensor, a suction line flow sensor, a hot gas line temperature sensor, a hot gas line pressure sensor, a hot gas line flow sensor, a liquid line temperature sensor, a liquid line pressure sensor, a liquid line flow sensor. In one embodiment, the sensors include one or more of an evaporator air temperature input sensor, an evaporator air temperature output sensor, an evaporator air flow sensor, an evaporator air humidity sensor, and a differential pressure sensor.

Abstract: A dust collection apparatus includes a container and a suction pump that sucks dust and transports it into the container. A filter is provided on a side surface of the container. This filter passes air but prevents passage of the dust in the container. A pressure detector detects an internal pressure of the container. The internal pressure of the container fluctuates due to a variation in an effective area of the filter for allowing the air to pass according to the dust collected and accumulated in the container. A dust accumulating quantity calculator which determines a quantity of the dust in the container based on the pressure detected.

Abstract: An end of service life indicator (ESLI) device for a fluid filter is included on the filter and visually indicates when the life of the filter has expired. The ESLI indicates the depletion of the filter by changing the color density on a surface of the device to a color density having a well distinguishable contrasting pattern that is easily recognizable even by individuals who are color-blind. The contrasting pattern may express text indicative of the state of the filter.

Abstract: A compact and highly portable combination pressure swing adsorption apparatus and product gas conservation device for medical use, to produce efficiently a gas with a high concentration of oxygen and to deliver the oxygen concentrated gas to a user at selectable times and in selectable doses.

Abstract: A system and method for passive hypoxic training provides a person with a low oxygen (hypoxic) environment. Oxygen sensors automatically monitor and control oxygen levels to maintain the altitude desired. CO2 levels are monitored and CO2 is eliminated so that the air a person breathes is substantially clean and fresh. Exposure to a high altitude environment produces physiological changes in a person's body, which becomes more efficient at absorbing and transporting oxygen. Using the present method and system, athletes obtain the benefits of sleeping at a simulated altitude in the user's own home for six to twelve hours, rather than traditional altitude therapies in which athletes spend two to three weeks at high altitude before an athletic competition to obtain similar benefits. This system allows for “live high train low” altitude training that has been shown in controlled studies to provide superior benefits to “live high train high” training.

Abstract: A compact and highly portable combination pressure swing adsorption apparatus and product gas conservation device for medical use, to produce efficiently a gas with a high concentration of oxygen and to deliver the oxygen concentrated gas to a user at selectable times and in selectable doses.

Abstract: A portable air purifier system and apparatus which includes a multi-element filter pack that is replaceable as a single unit, thus facilitating health safety of maintenance personnel. By serially disposing filter elements in order of descending sizes of particulates, filtering is improved. Selectably includable within the filters are materials that are particularly efficacious in removing contaminants such as acetone, ammonia, ozone, carbon monoxide, carbon dioxide, ethanol, methane, ethane, methanol, formaldehyde, hydrogen sulfide and other hazardous substances. By including an ultra-violet light source directed onto an activated charcoal layer, germicidal action is facilitated, and noise is abated through the advantageous employment of an expanded plenum and multiple right angle bends in air passageways.

Abstract: A system and method for passive hypoxic training provides a person with a low oxygen (hypoxic) environment. Oxygen sensors automatically monitor and control oxygen levels to maintain the altitude desired. CO2 levels are monitored and CO2 is eliminated so that the air a person breathes is substantially clean and fresh. Exposure to a high altitude environment produces physiological changes in a person's body, which becomes more efficient at absorbing and transporting oxygen. Using the present method and system, athletes obtain the benefits of sleeping at a simulated altitude in the user's own home for six to twelve hours, rather than traditional altitude therapies in which athletes spend two to three weeks at high altitude before an athletic competition to obtain similar benefits. This system allows for “live high train low” altitude training that has been shown in controlled studies to provide superior benefits to “live high train high” training.

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 filtration system, includes a filtration unit and processor. The filtration unit operates to filter ablative particles generated by thermal imaging of media and transmits a signal corresponding to a parameter, such as a pressure or pressure differential, representing a current state of the operation of the filtration unit, such as the state of the filters, during the filtering of the ablative particles. The processor receives the transmitted signals and generates, responsive to the receipt of the transmitted signal, a signal representing operator information associated with the current state operation, such as a warning or instructions for correcting a deficiency, and/or a signal to stop the imaging of the media.

Abstract: An exhaust gas cleaning system for an engine capable of judging the amount of trapped NOx and the oxygen storage capacity of an NOx trap agent and which can diagnose the deterioration of the NOx trap agent. The NOx trap is arranged in an exhaust gas passage and the air-fuel ratio of the exhaust gas is temporally changed from a lean air-fuel ratio to the stoichiometric air-fuel ratio or a rich air-fuel ratio with a predetermined cycle. The NOx trapping occurs by absorbing or adsorbing NOx in the exhaust gas when an air-fuel ratio of the exhaust gas is a lean air-fuel ratio and by releasing or reducing NOx when the air-fuel ratio is a rich air-fuel ratio. The amount of trapped NOx is judged from the oxygen concentration and the oxygen concentration in the exhaust gas is detected in the exhaust gas passage in the downstream side of the NOx trap and determined by taking the oxygen storage capacity when the air-fuel ratio of the exhaust gas changes to the stoichiometric air-fuel ratio or the rich air-fuel ratio.

Abstract: A gas separation plant includes, downstream of the line for feeding the gas separation module with a compressed gas mixture, a liquid particle separation device which includes a liquid detector, for example, of the optronic type, delivering an output signal, connected to an alarm device and to a central control unit of the plant.

Abstract: An apparatus and a method for trapping a toxic gas contained in an exhaust gas from a process chamber are disclosed. In the apparatus, two toxic gas traps are provided which are connected in series with a toxic gas sensor provided thereinbetween and in fluid communication with the two traps. When toxic gas is detected by the toxic gas sensor, i.e., an indication that the first toxic gas trap is fully consumed, the second toxic gas trap is used to replace the first toxic gas trap, while a new toxic gas trap is installed as the second toxic gas trap. The present invention novel apparatus and method enables the full use or utilization of a toxic gas trap and results in significant cost savings. Furthermore, the present invention novel apparatus and method improves the yield of a fabrication process by reducing the machine down time since the service frequency for the chamber is reduced.

Abstract: A device for continuously fractionating a gas by adsorption, an in-service testing device in a processor-controlled adsorption drier system and a method for testing the operating capability of an adsorption drier system under the control of a processor, including two adsorbent beds connected to one another in a switching system, in which regeneration is performed by a flow of regeneration gas. The device has a gas inlet, a gas outlet and a bypass outlet feeding into a common functional block, which contains a line switching circuit, a first and a second shuttle valve and, optionally, other components. The in-service testing device and the device are so compact due to their respective structures that they can be integrated with one another requiring little space and having low assembly requirements. The testing method is configured to co-operate with the in-service testing device and the device, requiring only a few components for the application thereof.

Abstract: A gas purification system includes a gas purification unit and one or more safety devices. The gas purification unit includes an enclosure containing a purification material that exhibits an exothermic reaction when exposed to certain gas contaminants. The gas purification unit also has an inlet coupled to an unpurified gas inlet line and an outlet coupled to a purified gas outlet line. A safety device can be coupled either to the unpurified gas input line or the purified output line, or both, and develops an alarm signal when gas contaminants exceed a given concentration level for a period of time.

Abstract: A chamber with drier comprises a clean chamber communicating with the outside environment through an orifice equipped with a detachable antechamber filled with desiccant granulates. The chamber comprises, between the orifice of the clean chamber and the detachable antechamber filled with desiccant granulates, a valve that is closed at rest and opened by the positioning, on the orifice of the clean chamber, of the antechamber filled with desiccant granulates and the antechamber filled with desiccant granulates contains a baffle that prevents the air from following a direct route and forces it to encounter the majority of the desiccant granulates. Advantageously, the baffle is convergent and there electronic monitoring of the moisture saturation of the desiccant granulates. Furthermore, there may be a single-effect back flow valve bypassing the baffle for a fast decompression of the clean chamber.

Abstract: A gas sampling apparatus includes a probe tube having a tip positionable in a stream of products of combustion and a sample dryer tube connected in fluid communication with an end of the probe tube opposite the tip. The sample dryer tube is received in a purge gas tube along a lengthwise axis thereof. The purge gas tube and the sample dryer tube define therebetween a space through which a purge gas pump urges a purge gas in a first direction. A sample pump connected in fluid communication with the sample dryer tube urges therethrough in a second direction opposite the first direction a sample of gas obtained from the stream of products of combustion via the probe tube. A sensor is positioned to detect a constituent of the sample of gas exhausted from the sample dryer tube. The sample dryer tube is formed at least in part of a hydrophilic membrane and the purge gas entering the space contains less water vapor than the sample of gas.

Abstract: A portable PSA oxygen generator that includes first and second filters for filtering inside air; a fan motor for passing through the air; a third filter for filtering the air intaken through the fan motor; a compressor assembly for compressing the air supplied; an oxygen concentrator for adding/eliminating oxygen to/from the compressed air supplied from the compressor assembly to generate the highly concentrated oxygen; an oxygen tank for storing the oxygen generated in the oxygen concentrator; an oxygen filter for filtering oxygen exhausted; a nitrogen filter for filtering and exhausting nitrogen; a pressure sensor installed inside the oxygen tank and outputting a signal indicating an internal pressure state; a failure alarming circuit made of buzzer connected with the pressure sensor in series, and a light emitting diode; a timer for limiting an operation time; an oxygen sensor for estimating the concentration of the oxygen exhausted through the oxygen filter; a control knob for controlling the concentratio

Abstract: A fluid storage and dispensing system including a fluid storage and dispensing vessel containing a physical adsorbent material having sorptive affinity for the fluid to be stored in the vessel and subsequently dispensed from the vessel through a valve head assembly. The character of the fluid stored in the vessel, such as its pressure and/or temperature, is non-invasively monitored during the storage (non-dispensing) mode of the system, by a sensing element in the valve head assembly operative coupled with an output device such as a visual output display or a set point-limited alarm.

Abstract: An environmental air is sucked by the pump with control unit, and organic solvent contained in the environmental air is collected by the absorbent. Organic solvent having passed through the absorbent is detected by the semiconductor gas sensor. If passage of a material to be measured is detected by the semiconductor gas sensor, operation of the pump with control unit is stopped, and the operation for collecting the material is terminated. Then the absorbent is taken out from the collecting tube, the material collected is quantified by means of gas chromatography, and the density is measured. With this configuration, measurement of a density of a material to be measured in a working environment can be executed accurately.

Abstract: A method of controlling an oxygen concentrator having a first sieve bed operated over successive control periods according to a duty cycle for alternately pressurizing and flushing the first sieve bed and a second sieve bed operated over the successive control periods according to a reciprocal of the duty cycle is disclosed. The duty cycle and the reciprocal duty cycle are adjusted during every second one of the successive control periods to change the pressurizing relative to the flushing of the first sieve bed and to change the flushing relative to the pressurizing of the second sieve bed, for reducing concentration of oxygen produced. The duty cycle and the reciprocal duty cycle are adjusted during remaining control periods to change the flushing relative to the pressurizing of the first sieve bed and to change the pressurizing relative to the flushing of the second sieve bed, such that water vapor is purged from the first and second sieve beds after pressurizing thereof.

Abstract: A chemical filter for removing a chemical impurity is arranged at an air inlet, and a gas sensor for adsorbing the chemical impurity is arranged upstream of the chemical filter. The service life of the chemical filter is determined on the basis of the resonance frequency of the gas sensor. Alternatively, the chemical filter has a specific portion whose removal capacity for the chemical impurity is lower than that of the rest, and a sensor for sensing the chemical impurity is arranged downstream of the specific portion. The service life of the chemical filter is predicted on the basis of an output from the sensor.

Abstract: A system for extracting nitrogen from air to produce a flow of nitrogen includes a compressor for compressing air and an air separator connected to the compressor for producing nitrogen from the compressed air. The compressor is provided with a reducing device for reducing an effective length of the rotatable rotors which acts to compress air in order to cause the compressor to operate at less than full capacity. An internal pressure control regulator operatively associated with the compressor regulates the discharge pressure from the compressor and provides a signal air pressure when the compressor discharge pressure exceeds a predetermined pressure. An external input device allows an external signal indicative of a compressor operating level that is less than full capacity to be inputted and provides a signal air pressure based on the external signal.

Abstract: The removal of components from fluid mixtures in aircraft utilizes an adsorbent bed which is regenerated by passing dry ambient air through the adsorbent bed when the aircraft reaches a height at which such dry ambient air is available. An example of mixtures that can be treated in this way are water/oil mixtures, air/water vapor mixtures and air/odor mixtures. By periodically regenerating the adsorbent bed in this way, an adsorbent bed of small size can be used but yet have a substantial life.

Abstract: A mobile regeneration apparatus is provided for regenerating dryers. The regeneration apparatus may be used to regenerate single tower desiccant dryers located at natural gas vehicle refueling stations. For optimum performance, each dryer may be located upstream of a respective compressor.