Abstract: A liquid dispensing method and apparatus in which liquid is dispensed from chambers, that can be pressure vessels, to a flow circuit. A valve network is designed such that when one chamber functions in a dispense mode of operation another chamber functions in a return mode of operation in which unused liquid is sent back to such chamber so that liquid is continually circulated. The chamber or vessel undergoing the return mode of operation is vented through a valve that is either a pressure regulation valve having a set point of pressure or a remotely activated control valve response to liquid pressure at the point of use. In such manner internal pressure within the chamber or pressure vessel undergoing the return mode of operation is regulated to in turn regulate liquid pressure at the point of use.

Abstract: An apparatus and method for purifying boron trichloride by removal of phosgene. In accordance with the invention, phosgene is photolytically decomposed into carbon monoxide and chlorine and liquid vapor phase in equilibrium with one another and in solution with the boron trichloride. This equilibrium is disturbed preferably by sparging a vapor stream that rises through the boron trichloride and is composed of the substance, such as nitrogen, to disturb the equilibrium and thereby cause the carbon monoxide and chlorine to be carried out of solution and collect in the overhead space. The decomposition product of chlorine and carbon monoxide can then be removed from the vapor space so that the carbon monoxide and chlorine to not recombine and contaminant the boron trichloride with phosgene.

Abstract: A method of processing semiconductor manufacturing exhaust gases for recovering at least hexafluoroethane in which a feed stream composed of the exhaust gases is passed through an adsorbent bed selected to adsorb oxygen, and also nitrogen if present, but not to appreciably adsorb the hexafluoroethane. As a result, a product stream, discharged from the adsorbent bed, has a higher concentration of hexafluoroethane than in the feed stream. In one embodiment, only a single adsorbent such as carbon molecular sieve is provided to adsorb the oxygen or a modified 4A zeolite could be used to adsorb both oxygen and nitrogen. When nitrogen is a potential constituent, layers of carbon molecular sieve and zeolite are provided to adsorb the oxygen and then the nitrogen, respectively. A third adsorbent, preferably 5A zeolite may be provided in addition to the foregoing two adsorbents to also adsorb any carbon tetrafluoride produced as a by-product.

Abstract: A method and apparatus for measuring metallic impurities within a fluid by X-ray fluorescence in which a sample stream flowing at a constant flow rate is passed through a microporous filter. The microporous filter contains substantially no metallic impurities and is configured to adsorb the particulate solid phase and vapor phase of the compounds. Excitation of the metallic compounds by X-ray produces an X-ray florescence having an intensity that can be measured. The change in intensity is compared with that produced by a calibrated inflow of a standard gas sample to derive the impurity concentration. In a preferred embodiment, the filter is housed within a chamber having a window that is preferably fabricated from Beryllium so as not to appreciably attenuate the X-rays.

Abstract: A road tanker for carrying two or more separate cryogenic liquids in which the inner tank of the vacuum insulated system is divided by a sheet of material of similar thermal expansion properties to those of the tank. This allows the cryogenic liquids to equilibrate in temperature. Also provided, external or internal to the tank, is a variable inline mixing system so that the appropriate mixture of cryogenic liquids can be dispensed upon delivery.

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 method and apparatus for storing and dispensing a liquid consisting of an oxygen containing mixture so that the liquid will not contain any more than a predetermined concentration of the oxygen at a predetermined pressure. In accordance with the invention, the mixture is introduced into the container at a specified initial concentration. A hypothetical volume of the saturated state of the liquid having the initial concentration is computed that when expanded into the total volume of the container, the resulting liquid would have the maximum enrichment. The liquid is dispensed from a bottom region of the container and dispensing is prevented when the liquid remaining within the container could possibly have the maximum enrichment computed at a particular dispensing pressure. Pressure relief methods are employed that avoid head space vapor being vented.

Abstract: The present invention provides methods and apparatus for freeze drying in which a solution, which can be a radioactive salt dissolved within an acid, is frozen into a solid on vertical plates provided within a freeze drying chamber. The solid is sublimated into vapor and condensed in a cold condenser positioned above the freeze drying chamber and connected thereto by a conduit. The vertical positioning of the cold condenser relative to the freeze dryer helps to help prevent substances such as radioactive materials separated from the solution from contaminating the cold condenser. Additionally, the system can be charged with an inert gas to produce a down rush of gas into the freeze drying chamber to also help prevent such substances from contaminating the cold condenser.

Abstract: A diffusion pump having a hollow outer body and a heater to heat working fluid that is used in the pump. The hollow outer body includes an outlet for connection to a backing pump and an inlet for communication with the chamber to be evacuated. A sump contains the working fluid and a reservoir for the working fluid surrounds the sump as an integral part of the hollow body. The surrounding reservoir decreases service intervals and reduces heat up and cool down time. The reservoir can be formed of two cylindrical surfaces concentric with the central axis of the pump.

Abstract: Air is supplied along a pipeline to an apparatus for separating an oxygen-enriched gas stream from the air by vacuum swing adsorption. The oxygen-enriched gas stream is supplied to a burner which fires into a furnace. A hot gas stream leaves the furnace through an outlet. Steam is raised from the hot gas in a waste heat boiler. Steam so raised flows through one or more of the eductors to draw through a pipeline the vacuum necessary for the operation of the vacuum swing adsorption apparatus.

Abstract: A method of separating air in a liquid nitrogen assist plant in which oxygen rich waste stream produced by the plant is used to partially pressurize adsorbent beds in a pre-purification unit operating in accordance with a pressure swing adsorption cycle.

Abstract: An sensor for sensing buoyancy force within a liquid mixture stored within a storage tank and an interlock employing the sensor to prevent a respirable cryogenic mixture from being dispensed from the storage tank with an unsafe oxygen content. The sensor has a float adapted to be submerged in the liquid mixture, thereby to exert a buoyancy force referable to the density. The buoyancy force is sensed by a load cell connected to an elongated base element cantilevered from the outlet by a bracket. The mounting of such sensor ensures that the buoyancy force and therefore, the density of the liquid as dispensed will be measured as opposed to liquid density at some other location of the tank. Such sensor can serve in an interlock in which a controller responsive to the load cell and a temperature sensor, also located within the outlet, controls a valve to close the outlet when the mixture has an unsafe oxygen level.

Abstract: A vacuum swing adsorption apparatus for separating a gas mixture includes a pipeline along which the vacuum is able to be drawn. The apparatus is provided with a plurality of eductors each connected to the pipeline 6 and in parallel with the other eductor respective stop valves. The stop valves are arranged and operable so as to select the number of eductors in communication with the pipeline. Thus the degree of vacuum to which the apparatus is subjected may be varied.

Abstract: A method of supplying both an oxygen steelmaking process and an ironmaking process with oxygen. The oxygen is separated from air by rectification of the air. A first stream of oxygen from the rectification to the steelmaking process. A second stream of oxygen is also supplied from the rectification to the ironmaking process. The first and second streams of oxygen are both withdrawn from essentially the same stage of the rectification and both contain from about 97 to about 98% by volume of oxygen and less than about 100 parts per million of nitrogen.

Abstract: White liquor produced from black liquor is partially or completed oxidized. The white liquor contains dregs that are utilized as a carbon based catalyst. Dregs are produced by separating the dregs from green liquor an intermediate product between the black liquor and the oxidized white liquor. After formation of the oxidized white liquor, the dregs are separated therefrom to form a waste dreg stream which can be recycled so that part of the dregs present within the dregs containing white liquor stream to be oxidized is contributed by the waste dreg stream.

Abstract: A method of and apparatus for mixing two cryogenic liquids in which a first amount of first cryogenic liquid is introduced into a vented vessel having one or more vents. The vent or vents are then closed and a second amount of a second cryogenic level is introduced into the closed vessel at a level above the surface of the first cryogenic liquid in the vessel. The second cryogenic liquid has a greater density or both a greater density and a higher boiling point temperature than that of the first cryogenic liquid, thereby to produce a substantially homogeneous cryogenic liquid mixture of predetermined composition.

Abstract: A method of operating a lower pressure of column of a double distillation column unit. In accordance with the method an ascending vapor phase is initiated within a lower pressure column by vaporizing a descending liquid phase at a column location situated between mass transfer elements and a sump region of the lower pressure column. The liquid phase is vaporized within two or more down-flow reboilers fed with the liquid phase so that the unboiled liquid from one of the down-flow reboilers is fed to another of the down-flow reboilers, thereby to cause vaporization to be distributed between the down-flow reboilers. The down-flow reboilers are configured such that sufficient vaporization occurs to produce a predetermined liquid-vapor ratio at the column location between the transfer elements and the sump without the requirement of recirculating sump liquid to prevent dry out.

Abstract: A process for the scrubbing of undesirable substances from an exhaust gas stream which comprises passing the stream through a hollow cathode.

Abstract: A burner construction having a body portion fabricated from a base material and coating material covering the base material. The base material is formed of copper or copper alloy having a conductivity of no less than about 100 watts/meter/.degree. C. Alternatively the base material can be silver. The coating material comprises nickel or nickel based alloy which can be an autocatalytic plating.

Abstract: A sensor for sensing buoyancy force within a liquid mixture stored within a storage tank and an interlock employing the sensor to prevent a respirable cryogenic mixture from being dispensed from the storage tank with an unsafe oxygen content. The sensor has a float adapted to be submerged in the liquid mixture, thereby to exert a buoyancy force referable to the density. The buoyancy force is sensed by a load cell connected to an elongated base element cantilevered from the outlet by a bracket. The mounting of such sensor ensures that the buoyancy force and therefore, the density of the liquid as dispensed will be measured as opposed to liquid density at some other location of the tank. Such sensor can serve in an interlock in which a controller responsive to the load cell and a temperature sensor, also located within the outlet, controls a valve to close the outlet when the mixture has an unsafe oxygen level.