Abstract: An impingement freezer having a zoned freezing chamber in which the temperature of each zone is independently controllable so that the temperature profile within the impingement freezer is coldest at a zone adjacent the outlet and warmest at a zone adjacent the inlet for maximum thermodynamic usage of the refrigerant. Additionally, the velocity of each of the impingement jets is independently adjustable from zone to zone so that in the zone adjacent the entrance of the freezing chamber, the impingement jets can be adjusted to have maximum velocity to produce maximum heat transfer coefficients and thereby an acceptable rate of cooling within the impingement jet freezer. Impingement jets are formed within nozzles that are tapered in two orthogonal directions to prevent frost build-up. Circulation within the impingement jet freezer is produced by venturi-like devices driven by vaporization of incoming refrigerant.

Abstract: A method for manufacturing a heat-sealed neo-natal medical monitoring probe requires a pair of light sources and a light detector to be placed between two layers or conformable material used to implement the probe. The layers are designed to be self-aligning when placed in the assembly press for heat-sealing the perimeter of the probe. The heat-sealing process both protects the light sources and detector from fluids and also functions to precisely position and secure these devices.

Abstract: A process of depositing thin film coatings by evaporation in which a plasma is formed in an evacuated chamber and a source of material to be evaporated is provided which is evaporated to produce evaporated material. A substrate to be coated is located within the chamber and the evaporated material is caused to pass through the plasma and be to be deposited on the substrate. The plasma is generated by a helicon wave.

Abstract: A vacuum pump of the scroll type having first and second scroll components each having a scroll structure defined thereon. The scroll components are arranged in the pump such that the respective scroll structures inter-engage with the first scroll component being held stationary and the second scroll component orbiting the first scroll component to trap a volume of gas and urge the volume from one end of the respective scroll structures to the other end. The first and second scroll components define inter-engaging scroll structures having an initial multi-start portion including at least two pump inlets and a subsequent single-start portion including a pump outlet.

Abstract: The menu selection device uses a combination of the rotary position of a rotary optical encoder and the operation of a coaxially mounted push-button switch to enable the user to progress through various layers of a hierarchical menu system. The rotary position of the shaft translates to a menu category which is selected by the user activating the push-button switch. The selection of the menu category allows the user to then sequence through the plurality of menu entries within this menu category by again rotating the shaft. The user selects one of these menu entries by again activating the push-button switch.

Abstract: In a pressure swing adsorption plant for the production of oxygen enriched gas a pressure vessel contains a first bed of molecular sieve adsorbent located adjacent an outlet 4 of the vessel which has an optimum operating efficiency at approximately ambient temperature and a second bed 10 of molecular sieve adsorbent which has an optimum efficiency below that of ambient operating temperature located adjacent the inlet 2.

Abstract: A structured packing for producing intimate contact between liquid and vapor phases formed of a plurality of juxtaposed sheets through which the liquid phase descends as a film. The sheets have corrugations to define flow channels through the sheets for the vapor phase to ascend through the structured packing and contact the liquid phase. The sheets have a plurality of elongated projections, situated on one or both sides of each of the flow chapels and/or each of the sheets. The projections are configured and oriented to produce turbulent mixing in the vapor phase as it ascends though the packing. This turbulence inhibits the formation of a concentration gradients within the vapor phase in directions normal to the walls of the flow chapels. The elongated projections are spaced apart from one another so that the turbulence and the vapor phase subsides between the elongated projections.

Abstract: Selected strongly adsorbed gaseous impurities are removed from a gas stream by pressure swing adsorption in an adsorption system which includes a single adsorption vessel, a gas storage vessel and a single gas pump. Feed gas is pumped at a selected adsorption pressure cocurrently through the adsorption vessel, which contains an adsorbent that selectively adsorbs the selected impurity or impurities. The less strongly adsorbed components of the gas mixture pass out the adsorption vessel through the nonadsorbed gas outlet end of the adsorption vessel. When the adsorbed gas front reaches a certain point in the adsorption vessel, the adsorption step is terminated and gas is countercurrently transferred from the adsorption vessel to a gas storage vessel, optionally with use of the gas pump. The adsorption vessel is then countercurrently evacuated by use of the pump and a selected gas-enriched product is recovered and sent to storage or further processed in downstream treatment operations.

Abstract: A pressure swing adsorption apparatus (10) is provided with actuator air via a reservoir (40) which draws its supply either from one or more of the process vessels (12) after it has been dried thereby or directly from the system compressor (32). Controls are provided to ensure actuator air is preferentially drawn from the dried source and for ensuring instrument air is available even on start up of the apparatus.

Abstract: A distillation apparatus having applicability to an air separation plant in which a distillation column is suspended within a containment sleeve from a main heat exchanger or a head condenser of the distillation column. The suspension of the distillation column is flexible so that the distillation column can assume a vertical orientation under influence of gravitational force to be self-leveling.

Abstract: A non-intrusive device for attachment to a pipe or vessel through which a fluid flows for monitoring the accumulation of deposits on the interior surface of the pipe or vessel. The device comprises a tubular member having an internal cross-sectional configuration substantially matching that of the pipe or vessel. Additionally, the tubular member is made of an electrically insulating material and having associated therewith three spaced electrodes for monitoring the change of dielectric constant within the pipe or vessel.

Abstract: Chabazite, offretite, erionite, levyne, mordenite, gmelinite, zeolite A, zeolite T, EMC-2, ZSM-3, ZSM-18, ZK-5, zeolite L, and beta zeolite whose exchangeable cations are composed of 95 to 50% lithium ions, 4 to 50% of one or more of aluminum, cerium, lanthanum and mixed lanthanides and 0 to 15% of other ions are prepared by ion-exchanging the base zeolite with water-soluble trivalent ion salts and with water soluble lithium salts. The zeolites preferentially adsorb nitrogen from gas mixtures.

Abstract: A level detector for detecting a level of a liquid is provided with an elongated probe having opposed proximal and distal ends. In use, the distal end of the elongated probe is submerged beneath the level of the liquid with an unwetted length of the elongated probe located above the level of the liquid. A thermal conductor or an electrical heater is provided for maintaining a temperature difference between the proximal end of the elongated probe and the liquid so that at an intermediate location of the elongated probe, located above the level of the liquid, the temperature will be dependent upon the unwetted length of the elongated probe. A thermocouple or the like can be provided for generating a signal referable to the temperature at the intermediate location and the level of the liquid can thereby be correlated with such signal.

Abstract: A method and apparatus for generating nitrogen from the separation of air in a single column nitrogen generator. Nitrogen rich vapor is condensed to form reflux through the vaporization of an oxygen-rich liquid stream produced as column bottoms. The vaporized oxygen-rich stream is in part recompressed in a recycle compressor, cooled and reintroduced back into the column to increase nitrogen production. The vaporized oxygen-rich stream is also in part expanded with the performance of work. The work of expansion is applied to the compression. A supplemental refrigerant stream produced by a nitrogen liquefaction unit allows the nitrogen to be taken as a liquid and increases the amount of work of expansion able to be applied to the compression.

Abstract: A hybrid vacuum pump comprising a turbomolecular stage positioned at the inlet end of the pump and comprising a stator formed from an array of stationary blades and a rotor formed from a further array of blades arranged for rotation at high speed between the stator blades. A molecular drag stage is positioned at the outlet (high pressure) end of the pump and comprises at least two discs arranged for rotation within a stator with a minimal clearance between the circumferential edge of the discs and the stator. A flow passageway linking the turbomolecular stage with annular channels is defined between the stator and opposing faces of the discs and projections extending from the stator are provided for deflecting gas being pumped from the annular channels during rotation of the discs.

Abstract: A first flow of air is compressed in a first air compressor associated with a gas turbine and is purified in an adsorptive purification unit which separates water vapour and carbon dioxide from the air. The purified first flow of air is further compressed to a pressure at least 5 bar higher than that at which it is purified in a second air compressor whose outlet pressure is independent of fluctuations in the power output of the gas turbine, is cooled in a main heat exchanger, is passed through an expansion valve, and is introduced into a higher pressure rectification column. A second flow of air is compressed in a third air compressor which is independent of the gas turbine. The compressed second flow of air is purified in an adsorptive purification unit by the separation of water vapour and carbon dioxide therefrom. The purified second flow of air is cooled in the main heat exchanger and is introduced into the higher pressure rectification column.

Abstract: An incinerator in which halogenated organic compounds are burned in the presence of oxygen or oxygen enriched air to produce combustion products. The combustion products potentially include unreacted oxygen and halogenated organic compounds which can react with oxygen to produce halogenated furans and dioxins. The formation of the halogenated furans and dioxins is minimized by firing a burner, burning a hydrogen containing fuel at a fuel-rich stoichiometry, into the combustion products so that the fuel will react with the unreacted oxygen. This will reduce formation of the halogenated furans and dioxins. Any of the halogenated furans and dioxins that are formed are substantially eliminated by the reaction of hydrogen supplied by the fuel with the halogenated furans and dioxins.

Abstract: A clamp for securing adjacent lengths of pipe. The clamp incorporates a seal designed to incorporate a temperature or pressure probe. The clamp is circular and has upstanding end portions and a threaded rod member passing through apertures in the upstanding end portions to secure flange ends of the adjacent lengths of pipe together. The rod member has an opening through which the temperature or pressure probe passes so that temperature pressure can be measured within the adjacent lengths of pipe. Furthermore, seal components held by a support member can be provided to seal the support member to adjacent lengths of pipe. The temperature or pressure probe passes radially through such support member.

Abstract: A method for effecting the initiation of a molecular process or reaction in a substance, which comprises bringing the substance into contact with a surface of a cold cathode device and applying an electric potential across the cold cathode device to cause electrons to be emitted from the surface thereof with an energy level sufficient to effect the initiation.

Abstract: A pressure vessel 1 forming part of a PSA plant contains a molecular sieve adsorbent. A plurality of thermocouples are located within the molecular sieve adsorbent such that one junction 8 of each thermocouple is positioned adjacent the feed gas inlet 2 of the vessel 1 while the second junction 10 of each thermocouple is positioned adjacent the product gas outlet 4 of the vessel.