Abstract: A system and method for improving the efficiency of a gas fractionalization system of the type having a compressor having an inlet for receiving air from the ambient environment. The system includes a sensor for sensing a parameter indicative of the flow of concentrated gas delivered from the gas fractionalization system to a patient. A multi-positional valve is disposed in line with the compressor for regulating the flow of air from the ambient environment into the compressor. A valve control manipulates the position of the multi-positional valve depending on the value of the parameter sensed by the sensor for regulating the quantity of air received from the ambient environment into the compressor inlet.

Abstract: A gas containment assembly including a containment enclosure defining an enclosed interior volume, with an exhaust inlet and an exhaust outlet for flow of exhaust gas into the enclosed interior volume through the exhaust inlet and flow from the containment enclosure through the exhaust outlet. A gas supply vessel and/or gas flow circuitry is provided in the interior volume of the containment enclosure. A back-migration scrubber unit overlies and is sealed to the exhaust inlet so that back-flow migration of gas from the gas supply vessel and/or gas flow circuitry in the interior volume of the containment enclosure is sorptively taken up by sorbent material in the scrubber unit and prevented from passing into an ambient environment in which said gas containment assembly is deployed. This arrangement permits significant reduction in the flow rate of exhaust gas through the gas containment enclosure without compromising the safety of the gas containment assembly.

Abstract: A method for controlling mass flow of a hydrocarbon feed stream to a steam reformer said stream consisting of hydrogen and of natural gas, naphtha, off-gas, LPG, or a mixture hereof, and

Abstract: A molecular sieve type gas separation apparatus (10) for separating product gas from a gas supply (14) includes at least one sieve bed (11-13) which during an adsorption charge phase of a cycle, adsorbs non product gas in the gas supply (14), and in a desorption regeneration phase of the cycle desorbs the previously adsorbed non product gas. The apparatus further includes an outlet (18) to which product gas is delivered during the adsorption charge phase, and an outlet (31) for non product gas during the desorption regeneration phase. A sensor (36) responsive to the concentration of a constituent in the product gas, and a control (20) to switch the apparatus (10) between the adsorption charge and desorption regeneration phases are further provided. The control (20) is adapted to adjust the duration of adsorption charge phase relative to the duration of the desorption regeneration phase in each cycle.

Abstract: A fan filter unit for use in cleanrooms is provided, which decreases efficiently the concentration of chemical substance existing in the atmosphere while the expansion of the air circulating space and the electric power consumption increase of the fan-driving motor are suppressed. The unit comprises an enclosure having an air inlet through which an outside air is introduced into the enclosure and an air outlet through which a cleaned air is emitted or discharged from the enclosure; a chemical filter mounted in the enclosure to remove chemical substance existing in the outside air; a dust filter mounted in the enclosure to remove dust existing in the outside air; a fan mounted in the enclosure to introduce the outside air into the enclosure through the air inlet and to emit the cleaned air to outside of the enclosure; and a bypassing path for returning part of the outside air that has penetrated the chemical filter to an upstream side of the fan without penetrating the dust filter.

Abstract: The present invention provides an improved cold gas-dynamic spraying process utilizing a carrier gas and small-diameter particulates whereby the particulate-laden carrier gas is directed to a ceramic filter unit where the particulates are separated out and the particulate-free carrier gas is analyzed and returned to the spraying process or to other gas purification systems.

Abstract: A gas chromatograph has a pressure sensor measuring a pressure in a sample introduction part, a flow control valve controlling carrier gas flow rate, a flow sensor measuring a flow rate of the carrier gas, a split flow path exhausting part of a carrier gas and sample from the introduction part, an exhaust valve placed in the sprit flow path, and a monitor screen. The controller controls the flow control valve to flow the carrier gas at the designated flow rate into the introduction part, reads an output of the pressure sensor after making the exhaust valve fully open, calculates a flow path resistance of the filter by using an output of the pressure sensor and a flow path resistance of the chromatographic column, and controls the monitor screen to display an indication for exchanging the filter when the calculated resistance reaches the preset value corresponding to a state in which the filter is stuffed.

Abstract: The invention maintains a nearly constant cycle pressure ratio along with a balancing of the adsorbent vessel effluents in a pressure swing adsorption process. The invention monitors cycle pressure ratio and subsequently alters the cycle step times and flows to sustain its value, thereby maximizing plant performance and avoiding unnecessary shutdowns. Maintaining a nearly constant pressure ratio assures that the plant production is optimized and that power consumption is minimized. The balancing of the adsorbent vessel effluents, using the corresponding waste purities, is used to further improve plant production.

Abstract: A system for discharging gas emitted from an apparatus or facility having a vacuum pump which sucks the gas emitted from the apparatus or facility while being supplied with a gas other than the sucked gas, the system comprising a unit for recovering at least part of the gas discharged from the vacuum pump, and recirculating the recovered gas to the vacuum pump as the gas other than the sucked gas. Part of the recovered gas may be recirculated to the apparatus or facility emitting the gas. The system reduces or eliminates emission to the atmosphere of global warming gases such as perfluorocompounds discharged from the vacuum pump, and also reduces the energy required for operating the vacuum pump. A method for discharging gas emitted from an apparatus or facility using a vacuum pump, wherein emission of global warming gases to the atmosphere is reduced or eliminated, is also disclosed.

Abstract: In this process, the apparatus for separating the feed gas is connected to the delivery side of at least one variable-rotation-speed compressor, whose speed is controlled on the basis of the measurement of a parameter representative of the flow of gas product. The process is useful in the production of nitrogen from atmospheric air.

Abstract: An enclosed tank with a liquid inlet, a liquid outlet, a gas inlet, and a gas outlet. A liquid is forced to flow turbulently through the tank. Simultaneously a scrubbing gas is pumped through the tank. Turbulence induced in the liquid encourages gasses dissolved in the liquid to transfer to the scrubbing gas and thence to exit the gas outlet. Liquid pressure is provided externally to the invention, such as by a water utility or house water pump. The liquid inlet has a nozzle that injects the liquid against baffles in the tank to create turbulence. The liquid level in the tank is stabilized by controlling the scrubbing gas pressure. A lower layer of liquid and an upper layer of scrubbing gas are maintained in the tank as they flow through the tank together. Various liquid level stabilizing means are shown as examples. An electronic feedback system optionally controls the scrubbing gas flow rate according to the contamination level of the liquid.

Abstract: A vapor recovery system employs a sensor apparatus for determining the actual content of hydrocarbon in the effluent vapor stream. The vapor flow of the hydrocarbon effluents is regulated by controlling an adjustable valve configured at the intake or outtake side of the vapor pump in accordance with the measured hydrocarbon content. The vapor flow rate is effectively varied without requiring any change in the pump operating speed. Sensor apparatus for performing the hydrocarbon measurements include a fiber-optic sensor, an oxygen sensor, and a crystal oscillation sensor. A solenoid assembly is provided to suitably activate the valve in response to the sensor measurement data.

Abstract: An object of the present invention is to provide a method for recovering a gas using a semipermeable membrane in an apparatus having a simple structure. The method is capable of maintaining a purity of a product gas at a constant value even if a feed amount of a feed stream is fluctuated. A feed stream G1 is a gas mixture of a fast gas having a relatively high permeability to a membrane 1 and a slow gas having a relatively low permeability to the membrane 1. The feed stream G1 is pressurized by a compressor 3 and fed to a membrane 1 separation unit 2 having the membrane 1. Part G7 of the permeate stream on the permeate side of the membrane 1 is recirculated to the upstream side of the compressor 3 through the first recirculation line 17 and merged into a stream of the feed stream G1. Simultaneously, another part of the permeate stream G2 on the permeate side of the membrane 1 is recovered through a product gas recovering line 5.

Abstract: A method for the in-situ predetermination of the effects of NOx reduction systems on selected components. This determination can yield quick, inexpensive and accurate results for a number of characteristics, for example: catalyst longevity; efficiency with differing fuels, in differing locations, and at different temperatures; potential of catalyst poisoning in specific circumstances; ammonia slip considerations; SCR and SNCR interplay, as well as staged NOx reduction design criteria; pressure and blockage considerations; downstream effect on air preheater elements; and more. These determinations can be made in real, or accelerated time. Furthermore, the determinations can be made before any system modifications are made, or to assist in increasing the efficiency of existing systems, or even to assist in predictions of preventive maintenance and associated down time.

Abstract: A molecular sieve type gas separation apparatus (10) for separating product gas from a gas supply (14) includes at least one sieve bed (11-13) which during an adsorption charge phase of a cycle, adsorbs non product gas in the gas supply (14), and in a desorption regeneration phase of the cycle desorbs the previously adsorbed non product gas. The apparatus further includes an outlet (18) to which product gas is delivered during the adsorption charge phase, and an outlet (31) for non product gas during the desorption regeneration phase. A sensor (36) responsive to the concentration of a constituent in the product gas, and a control (20) to switch the apparatus (10) between the adsorption charge and desorption regeneration phases are further provided. The control (20) is adapted to adjust the duration of adsorption charge phase relative to the duration of the desorption regeneration phase in each cycle.

Abstract: In a gas purifier, a gas flow is generated by a fan (15) and passed through a filter arrangement (14). A difference (SF) is measured (16, 19) between pollution levels in the gas flow before and after it has passed the filter arrangement (14). A controller (18) reduces the gas flow when the difference (SF) between the pollution levels drops below a threshold value (Th).

Abstract: A system for controlling the atmosphere in the container comprising a membrane separation apparatus to separate nitrogen and a second separation apparatus, adapted to separate carbon dioxide and water vapor from a gas mixture in the container. The separated nitrogen is returned to the container, as is at least a portion of the carbon dioxide and water vapor, so as to produce and/or maintain a pre-determined atmosphere composition within the container thereby to prevent spoilage of perishable products within the container.

Abstract: A telescopic firearm scope/sight which is fully integrated with a compact digital camera, and which has size, shape and weight characteristics that are substantially the same as those of a conventional, camera-less telescopic scope, is used to photograph a target proximate the instant at which the target is fired upon. To configure the weapon for photography and firing, the scope is simply placed on the firearm in the same manner as a conventional scope, and the firearm is then fired in the conventional manner. Photographs are recorded, alternatively, in response to the sound of, or the recoil from, the firearm firing.

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 apparatus for storage and dispensing of a gas, comprising a gas storage and dispensing vessel holding a physical sorbent medium and gas adsorbed on the physical sorbent medium, wherein a carrier gas, e.g., helium, hydrogen, argon, etc., is flowed through the vessel to effect desorption of the sorbate gas and entrainment of the desorbed gas in the carrier gas stream. The storage and dispensing system of the invention may be employed to provide the dispensed sorbate gas to a downstream locus of use in applications such as epitaxial film formation and ion implantation, in the manufacture of semiconductor devices.

Abstract: The effluent gas stream from anaerobic waste water treatment digesters is treated to remove trace amounts of hydrogen sulfide and other contaminants. The chemical equation involved relies on the reaction of hydrogen sulfide with oxygen to form water plus elemental sulfur. The removal system includes a variable control line for adding air to the effluent gas stream; a filter for removing solids, entrained liquids and bacteria from the oxygen-enriched gas stream; a blower for directing the filtered gas stream into a potassium promoted activated carbon bed wherein the above chemical reaction takes place; and sensors for measuring the content of oxygen and hydrogen sulfide at the entrance and exit of the activated carbon bed. When the hydrogen sulfide content of the exiting gas stream exceeds a predetermined level, the amount of air added to the gas stream is increased until the predetermined level of hydrogen sulfide is achieved in the exiting gas stream.

Abstract: A spray booth includes an outer enclosure in which the temperature and humidity of a fluid (such as air) is not controlled and a fluid handling unit within this enclosure, which circulates and controls the temperature and humidity of a smaller volume of the same fluid (air) to develop an environment suitable for application of coatings to desired substrates. In use, fluid is drawn from the outer enclosure into the inner, fluid handling unit in order to clean and modify the temperature and humidity of the fluid being handled, conditioning it to be delivered to the region of limited size which is established for receiving the substrate to be coated.

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.

Abstract: An oxygen concentrator is provided which has a first molecular sieve bed connected to a four-way valve (i.e., a cross-over valve) which either joins the sieve bed to a pressurized air source (compressed air) or alternatively vents it to atmosphere. A second molecular sieve bed is also joined to the four-way valve in a corresponding manner. The sieve beds are joined at the outlet end to a product reservoir. The sieve beds are also in fluid communication at the outlet end by a pressure equalization flow path. A concentration equalization valve regulates the flow in the pressure equalization flow path. In accordance with the present invention, the microprocessor uses a closed-loop feedback circuit to evaluate the amount of time that the output product gas is allowed to flow into the used sieve bed. Specifically, an incremental step advance is used assuming a peak value of the time of flow one direction as compared to the time of flow in the second direction.

Abstract: An ozone storage system which allows energy required for producing and storing ozone to be reduced and which supplies ozone as stored to an ozone consumer stably in continuation.

Abstract: A system that includes an equipment package for separating nitrogen from air to produce enhanced oxygen air for use by divers. The package is combined with a pressure storage tank for air that is coupled to the package. A pressure storage tank is provided for enhanced oxygen air. A fill station including a high pressure gauge and a high pressure oxygen sensor is provided to fill divers' tanks. A compressor receives the enhanced oxygen air from the package and delivers high or low pressure enhanced oxygen air to the pressure storage tank via a pressure filter. Valving is provided for selectively controlling the flow in the system.

Abstract: A system for generating oxygen enriched air includes a compressed air supply for supplying compressed air and a permeable membrane gas separation system for separating a nitrogen gas component and an oxygen enriched air component from the compressed air. An oxygen analyzer is provided to detect an oxygen concentration in the oxygen enriched air component. The nitrogen gas component is divided, by a vortex tube, into a cold gas stream and a hot gas stream, and solenoid valves are actuated to modify a flow path of the compressed air through the cold gas stream and the hot gas stream in order to selectively heat and cool the compressed air. The oxygen enriched air is then selectively distributed for further use.

Abstract: A system for generating oxygen enriched air includes a compressed air supply for supplying compressed air and a permeable membrane gas separation system for separating a nitrogen gas component and an oxygen enriched air component from the compressed air. An oxygen analyzer is provided to detect an oxygen concentration in the oxygen enriched air component. The nitrogen gas component is divided, by a vortex tube, into a cold gas stream and a hot gas stream, and solenoid valves are actuated to modify a flow path of the compressed air through the cold gas stream and the hot gas stream in order to selectively heat and cool the compressed air. The oxygen enriched air is then selectively distributed for further use.

Abstract: An apparatus reduces the pressure in a fuel tank ullage including a first conduit for connection to the fuel tank ullage, a vapor extractor, a pressure sensor to detect the pressure in the fuel tank ullage, a separation module having an inlet connected to the first conduit, a separation membrane, a permeate outlet separated from the inlet by the separation membrane, and a retentate outlet, a second conduit connected to the permeate outlet for connection to the fuel tank, a vapor pump associated with the second conduit for creating a low pressure in the separation module near the permeate outlet as to induce selected vapors to pass through the separation membrane, a vent associated with the retentate outlet to vent retentate to atmosphere, a hydrocarbon detector to detect hydrocarbon concentrations in the vent, and a controller to receive inputs from the pressure sensor and the hydrocarbon detector and output control signals to the vapor extractor and the vapor pump to pull vapor from the ullage when the press

Abstract: A process for treatment of a secondary gas including ozone, comprising the steps of:a) adding an adjacent gas including CO.sub.2 to the secondary gas to form a mixture of secondary gas and adjacent gas;b) passing the mixture of secondary gas and of adjacent gas obtained at the end of stage a) into at least one stock of adsorbent, where the ozone is completely or partly adsorbed;c) sweeping the stock of adsorbent with the aid of a desorbing gas including CO.sub.2, and discharging from an outlet of the stock an output gas including ozone, wherein the ozone has a concentration which is higher in the output gas than the ozone concentration of the secondary gas.

Abstract: A process of removing carbon dioxide from a liquor in a vessel comprises the step of continuously passing a portion of the liquor into a sidestream and introducing discrete bubbles of between 0.005 mm and 1.0 mm diameter of nitrogen rich gas into the liquor before returning it to the vessel in which the nitrogen acts to adsorb carbon dioxide from the liquor and is then expelled from the liquor as an off-gas. The process also includes introducing a gas to be dissolved in the liquor into the sidestream as discrete bubbles having a diameter of between 0.005 mm and 1.0 mm.

Abstract: An apparatus and method for controlling the output of an oxygen concentrator wherein an oxygen concentrator indicator is comprised of an oxygen sensor monitor and circuit board which receives a gas sample from the concentrator, the oxygen concentrator indicator circuit board converts the concentration of oxygen to a DC voltage range from 0 to 1 volt corresponding to 0% to 100% oxygen. A plurality of set-point amplifiers accept the voltage and feed the voltage to a logic block where the voltage is analyzed to insure that only one of a plurality of solid state relays or switches is energized at a time. A plurality of taps on an AC motor winding are selectively energized by the solid state relays to drive the oxygen concentrator at a pre-determined rate in response to the concentration of oxygen generated by the concentrator.

Abstract: A rotary valve at the inlets of a plurality of columns cyclically (1) selects first columns on a cyclic basis to receive compressed air, adsorb nitrogen and other components in the compressed air and pass oxygen and argon to a user (e.g. patient), second columns to desorb the adsorbed components in such columns and (3) third columns to equalize pressures where the first columns change progressively to the second columns and vice versa. A compressor having adjustable characteristics and regulated in an open or closed loop introduces the compressed air through the valve to the first columns to provide an adjustable air flow for obtaining a prescribed oxygen flow to the user. An indication may be provided when the compressor characteristics regulated for obtaining the prescribed oxygen flow rate are outside particular limits. The valve may have a variable speed related to the compressor flow variations to regulate the air pressure in the columns in accordance with the air flow rate into the columns.

Abstract: A method for performing a function or an operation involving a material, in particular, a non-gaseous material such as a biological material subjected to a scientific investigation, under a gaseous atmosphere in a closed chamber comprising performing the operation in a housing comprising i) first chamber walls defining a first chamber containing a gaseous atmosphere and ii) second chamber walls defining a second chamber substantially enclosing the first chamber, the second chamber containing a gaseous atmosphere between the first and second chamber walls, the operation being performed in the first chamber while a) the partial pressure of the selected gas species or the total gas pressure in the atmosphere of the second chamber is lower than the partial pressure of the selected species of the total gas pressure, respectively, of the gaseous atmosphere in an adjacent outer third chamber or space. The invention also relates to a housing for performing the operation mentioned above.

Abstract: A nitrogen generation control system and method are provided for controlling levels of nitrogen and oxygen in a controlled atmosphere within a container for perishable goods. The nitrogen generation control system has a nitrogen generator that controllably generates an amount of nitrogen, while releasing oxygen as an off gas. The nitrogen is injected into the container to create a controlled environment. A sample analyzer subsystem is connected to the container to extract a sample of gases from the controlled environment and analyze the oxygen content. The control system further includes a cascaded, dual control loop controller coupled to the nitrogen generator and sample analyzer subsystem. The controller has a nitrogen generation control loop to control the amount of nitrogen generated by the nitrogen generator in response to variation between the oxygen released during nitrogen generation and a reference amount of oxygen.

Abstract: An apparatus reduces the pressure in a volatile chemical tank ullage including a first conduit for connection to the volatile chemical tank ullage, a vapor extractor, a pressure sensor to detect the pressure in the volatile chemical tank ullage, a separation module having an inlet connected to the first conduit, a separation membrane, a permeate outlet separated from the inlet by the separation membrane, and a retentate outlet, a second conduit connected to the permeate outlet for connection to the volatile chemical tank, a vapor pump associated with the second conduit for creating a low pressure in the separation module near the permeate outlet as to induce selected vapors to pass through the separation membrane, a vent associated with the retentate outlet to vent retentate to atmosphere, a VOC detector to detect VOC concentrations in the vent, and a controller to receive inputs from the pressure sensor and the VOC detector and output control signals to the vapor extractor and the vapor pump to pull vapor fr

Abstract: This invention relates to a self-regulated apparatus and method for extracting biodegradable and/or strippable constituents from a gaseous stream by the action of biomass which consumes or degrades such substances. Such self-regulation permits the monitoring and optimization of the bioactivity of the system and the overall degree of treatment of the gaseous stream.

Abstract: An apparatus reduces the pressure in a volatile chemical tank ullage including a first conduit for connection to the volatile chemical tank ullage, a vapor extractor, a pressure sensor to detect the pressure in the volatile chemical tank ullage, a separation module having an inlet connected to the first conduit, a separation membrane, a permeate outlet separated from the inlet by the separation membrane, and a retentate outlet, a second conduit connected to the permeate outlet for connection to the volatile chemical tank, a vapor pump associated with the second conduit for creating a low pressure in the separation module near the permeate outlet as to induce selected vapors to pass through the separation membrane, a vent associated with the retentate outlet to vent retentate to atmosphere, a VOC detector to detect VOC concentrations in the vent, and a controller to receive inputs from the pressure sensor and the VOC detector and output control signals to the vapor extractor and the vapor pump to pull vapor fr

Abstract: A vacuum cleaner including a dirty air inlet (12, 14) communicating with a clean air outlet by way of an airflow path has a cyclone (18) arranged in the airflow path. In use, air flowing along the airflow path from the dirty air inlet (12, 14) to the clean air outlet passes through the cyclone (18). At least one bleed valve (20) is arranged in the wall of the airflow path upstream of the cyclone (18). Preferably, three bleed valves (20) are located in the wall of the airflow path and, more preferably, the bleed valves (20) are substantially identical to one another. Control may be provided for controlling the amount of air bled through the bleed valve (76) when a single bleed valve is provided.

Abstract: Oxygen is separated from a feed air stream to produce enriched oxygen permeate and oxygen depleted retentate gas. At least first and second process stages, arranged in series, each include a solid electrolyte membrane separating gas chambers with a retentate side in the former and a permeate side in the latter, a cathode connected to the retentate side, and an anode connected to the permeate side. Feed gas is introduced into a first gas chamber of the first process stage. The cathode and anode of the first process stage are electrically energized to drive oxygen from the feed gas in the first gas chamber through the electrolyte membrane at a first flux into a second gas chamber. Oxygen-depleted retentate gas from the first process stage is delivered to a third gas chamber of the second process stage. Similarly, the cathode and anode of the second process stage are electrically energized by a current less than that of the first process stage and at a greater voltage.

Abstract: A process and apparatus for the selective recovery of solvents from solvent gas mixtures according to which the solvent gas mixture undergoes a sorption process, individual solvent gas fractions are fractionally desorbed from the sorption agent, condensed at staggered time intervals, measured to determine their composition, and collected separately.

Abstract: A method for the selective control of the sulfur trioxide concentration in flue gases, to enhance the ash removal efficiency of electrostatic precipitators, which includes: catalytically converting a portion of the sulfur dioxide contained within the flue gas to sulfur trioxide, by passing a portion of such flue gas through at least one catalyst containing converter module which is positioned within such a flue gas stream; and selectively varying the quantity of flue gas passing through such module by providing an aspirating force to cause flue gas to be drawn through such a converter module.

Abstract: Oxygen of uniform purity is produced in a two-bed air-fed oxygen pressure swing adsorption process in which the beds are operated out of phase. The steps of the adsorption cycle include a pressurization/production step and a bed regeneration step, with the bed undergoing regeneration being purged with a low pressure stream of the oxygen-enriched gas produced as the nonadsorbed product of the process. The oxygen concentration in the purged gas effluent is continuously periodically monitored, and the maximum oxygen concentration in the effluent during selected purge steps is compared with the maximum oxygen concentration in the effluent during a previous purge step, and the difference is used to adjust the timing and duration of a purge step following the selected purge step in a manner that reduces the difference between the oxygen concentration in the sequential purge steps.

Abstract: A process for supplying a flow of nitrogen to a site having flowrate requirements varying between a nominal flowrate and a range situated thereabove comprising: a) passing compressed air into a main line in a separating assembly formed by at least two membrane separation lines mounted in parallel, wherein at least one of the separation lines can be shut off from the main line, the separating assembly having one of the following configurations: a1) when the flowrate requirements are situated at a level of the nominal flowrate, all of the membrane separators of the assembly are in operation, none of the separating lines being shut off; a2) when the flowrate requirements of the site exceed a predetermined flowrate, at least one of the lines of the separating assembly is shut off, keeping at least one separation line and its membrane separator in operation; b) advancing nitrogen gas obtained at the outlet side of each of the membrane separators to a collector connected downstream of the main line; c) evacuating g

Abstract: A process for removing undesirable constituents from a gas, including providing an immovable, non-combustible woven adsorbate element, passing a flow of the gas through the element so that the gas is sharply deflected in the element and so that the constituents are adsorptively added to the element, interrupting the gas flow when the element reaches a maximum load of adsorbed constituents, directly heating the element while the gas flow is interrupted, by applying an electric voltage, to a process temperature of at 200.degree. C.

Abstract: Air is separated in a vessel housing gas separation membranes. A flow control valve controls the passage of air to an inlet header of the vessel. The setting of the valve is adjusted in accordance with the level of oxygen impurity in product nitrogen leaving the vessel for an outlet header. A second flow control valve is provided and is of a kind whereby product nitrogen is able to be delivered at a constant flow rate over a range of different pressures upstream thereof. Accordingly, the apparatus is able to deliver nitrogen at a desired purity and flow rate.

Abstract: A chemical processing system for generating ultra-pure chemicals near the site of use. The system includes in series a supply of chemical or the site of use which may be a tank or drum and may be a point of use for semiconductor manufacturing, a concentrate sensor, a pump, a filter, a reactor vessel, and an optional heat exchanger, all connected by Kel-F tubing. Sources of pure filtered gas connect to the reactor vessel. An ozone generator can likewise connect to the reactor vessel. An optional isolation coil can likewise connect between the gas source and the reactor vessel.

Abstract: According to the disclosure the amount of wind for an air cleaner is controlled regardless of the initial value of the air pollution level sensed by a sensor in an air cleaner. This allows the air cleaner to efficiently perform the air cleaning regardless of the area in which the air cleaner is installed. The method for cleaning the air requires that an initial value of the air pollution is sensed. Thereafter, an air pollution grade from a plurality of air pollution grades having a plurality of blow control sections set according to each of the air pollution grades. A present value of the air pollution is then sensed. An increment of air pollution is determined from the initial value of the air pollution and the value of the air pollution sensed at a later time. Based on this increment that has been determined, the amount of air from the air cleaner is controlled depending on that increment.

Abstract: A process for inerting an interior of a container, the process comprising:(a) introducing an inert fluid rich stream into the interior of the container, the concentration of inert fluid in the inert fluid rich stream inert fluid being greater than the inert fluid concentration in the interior of the container;(b) increasing the concentration of inert fluid in the inert fluid rich stream during its introduction into the interior of the container; and(c) withdrawing or purging a waste gas stream containing at least one impurity and inert fluid from the interior of the container.

Abstract: The present invention pertains to a process for purifying the exhaust air from plant parts of oil mills, in which the exhaust air removed from the plant is returned, after part of it had been discharged, into the plant in a cycle.