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 liquid-vapor contact device having a plate-like body provided with a central section formed of expanded metal construction. The expanded metal construction provides slit-like openings for the vapor to ascend through the plate-like body and mix with liquid traversing the plate-like body. Tongue-like flow deflectors associated with the openings impart momentum to the vapor in a flow direction taken from inlet and outlet segments of the plate-like body. A plurality of elongated members overlie the central segment of the plate-like body. The plurality of the elongated members define channels running from the inlet and outlet segments which are preferably outwardly curved to ensure complete liquid distribution across the plate-like body. In addition, flow impedance members in the form of cut and bent tabs impede the flow of liquid across the plate-like body while flinging liquid against side surfaces of the elongated members to produce a falling film and therefore a secondary mechanism for liquid-vapor contact.

Abstract: Method and apparatus for continuously freezing a food product in which the food product is contacted on a conveyor with a liquid refrigerant under conditions of turbulent flow to thereby freeze at least the outer surface of the food product. The frozen food product and the liquid refrigerant are thereafter separated.

Abstract: A substantially U-shaped immersion freezer having an inlet and an outlet and an immersion zone filled with liquid refrigerant. Product to be frozen is passed into the freezer through the inlet and raised by at least one paddle member to the outlet. The resulting frozen product and some liquid refrigerant is then passed out of the outlet to a conveyor having holes provided therein which allow the liquid refrigerant to be drained from the frozen product for recycling back to the inlet side of the freezer.

Abstract: The present invention provides a shelf for a freeze dryer which includes a pair of first and second flat plates spaced apart from one another, and a plurality of ribs located between the first and second plates and spaced from one another so as to define flow channels for circulating a diathermic fluid. The ribs are preferably formed of hollow tubes that are brazed to the first and second plates and the hollow tubes and plates are stress relieved so that the first plate presents a flat surface at which heat is transferred from articles to be freeze dried and the diathermic fluid. A freeze dryer shelf constructed in such manner has less thermal mass than prior art design which have solid ribs and plates welded to the ribs with a thickness sufficient to prevent the formation of surface deformations that would interrupt the flat surface of the first plate.

Abstract: A device comprises an elongate, tubular sheath (4) having an anterior and a posterior end (6; 8), a pointed needle (18) arranged in the sheath (4) for displacement between a first and a second end position, a catheter (26) initially supported by the needle (18), and an attachment for displacing the needle (18) between the first and the second end position. The novelty of the invention resides in that the sealing means for sealing the anterior, initially open end (6) of the sheath (4) is detachably connected to the attachment, that the sealing means further is detachably connected to the catheter (26), that the sealing means, during the displacement of the needle (18) from the first to the second end position, is moved towards the anterior end (6) of the sheath (4) to a sealing position, and that the sealing means is fixed in the sealing position for substantial sealing of the anterior end (6) of the sheath (4).

Abstract: A method and apparatus for determining the composition and concentration of gases present in a gas sample by measurement of the spectrum of Raman scattered light from these gases. A diode laser illuminates the unknown gas which is contained inside a long hollow tube having a highly reflective interior wall. A laser line pass filter at an entrance aperture of the hollow tube prevents all wavelengths except specific wavelengths characteristic of the laser from entering the long hollow tube. The laser beam and Raman scattered light from the gas sample reflect inside the hollow tube from the highly reflective interior wall. A laser line rejection filter at an exit aperture of the hollow tube prevents the laser beam from exiting the hollow tube but transmits the Raman scattered light from the gas sample. A spectrograph detector or array of discrete filters and detectors detects the Raman scattered light.

Abstract: A pressure regulator for lower pressure distribution of gases from a higher pressure source of gas including a gas inlet and a gas outlet defining a gas path therebetween, a regulating element disposed downstream of the gas inlet remote from the gas path, including a resiliently displaceable device responsive to gas pressure and connected to a valve at the gas inlet to thereby regulate the gas pressure at the gas outlet, and to gas distribution systems employing the same.

Abstract: The components of a gas mixture are separated by pressure swing adsorption in a plurality of adsorption vessels. In the first step of the half-cycle adsorption takes place in a first bed while the second bed undergoes countercurrent desorption. At the end of the first step the first bed is vented countercurrently and the first and second beds undergo, as a first bed equalization step, outlet-to-outlet equalization or outlet to both inlet and outlet equalization. The vent step may precede or be concurrent with the first bed equalization step. In a second equalization step the beds simultaneously undergo inlet-to-inlet and outlet-to-outlet equalization. The second bed is then further pressurized with nonadsorbed product gas. The half cycle is then repeated but with the first bed being substituted for the second bed and vice versa.

Abstract: An improved apparatus for the introduction of a gas into a liquid comprising a mixing device formed by a first generally convergent section and a second generally divergent section, said first section having a narrow outlet end of smaller diameter than an inlet end of said second section and extending thereinto so as to form an annular gap therebetween, and supply means for supplying said gas to said annular gap so as to facilitate the mixing of said gas with any liquid passing therethrough. The mixing device is preferably positioned at or near the surface of the liquid so as to avoid problems associated with hydrostatic head. The apparatus is advantageous in the treatment of a liquid with oxygen which is preferably generated by a Pressure Swing Adsorption device.

Abstract: An anaesthetic vaporizer includes a concentration dial for controlling the concentration of anaesthetic leaving the vaporizer. The vaporizer is adapted to be mounted on a back bar of an anaesthesia machine. An exclusion pin is mounted adjacent the back bar and forms part of an interlock system for preventing rotation of the concentration dial when a second vaporizer is also mounted on the back bar and is dispensing anaesthetic vapor. A button assembly is mounted on the concentration dial and must be depressed before the concentration dial can be rotated. The button assembly incorporates an overload device which, if excessive force is applied to the button assembly in order to override the effect of the exclusion pin will render the button assembly inoperative.

Abstract: Apparatus and method for chilling foodstuffs in which liquid cryogen is more effectively dispersed to chill the foodstuffs and cryogenic vapor generated by the liquid cryogen is used to remove residual liquid cryogen from the apparatus and for other useful purposes including freezing the foodstuffs.

Abstract: An oxy-fuel burner system for alternately or simultaneously burning gaseous and liquid fuels. A gaseous fuel jet emanating from an oxy-fuel burner is either undershot by an oxygen lance or is sandwiched between oxidant jets produced by two subsidiary oxidant jets which are preferably formed of oxygen. An actuable second fuel nozzle is provided for producing a second fuel jet composed of the liquid fuel which is angled toward the oxidant jet at an angle of less than 20.degree.. When the liquid fuel to be used, the gaseous fuel is turned off and the liquid fuel is turned on and vice-versa or both can operate simultaneously where the oxidant supplies oxygen to both fuel streams.

Abstract: A gas mixture comprised of nitric oxide and, optionally an inert gas, and containing small amounts of nitrogen dioxide, and perhaps moisture and sulfur dioxide, is purified by passing the gas stream through a bed of metal cation-free silica, alumina, or zeolite. The concentration of nitrogen dioxide, sulfur dioxide and moisture in the gas stream are significantly reduced as the gas mixture passes through the bed of adsorbent.

Abstract: An air separation method and apparatus in which a stream of air is compressed in a compressor and purified in a unit. One stream of the resulting air is cooled in a heat exchanger and is separated in an arrangement of rectification columns comprising a higher pressure rectification column, a lower pressure rectification column, and a further rectification column for separating argon from an argon-enriched oxygen stream withdrawn from the lower pressure rectification column and the stream of resulting air is introduced into the higher pressure rectification column through an inlet. A second cooled, compressed, purified air stream is expanded in an expansion turbine and is introduced into the lower pressure rectification column. A third cooled, compressed, purified air stream is expanded in a second expansion turbine and is introduced into the higher pressure rectification column.

Abstract: A wave soldering process and apparatus in which a localized low oxygen-containing atmosphere is provided at the point of contact of the solder wave and the substrate to be soldered by bubbling an inert gas through the solder wave.

Abstract: A vaporizer for introducing a vapor of an anesthetic liquid into t carrier gas for introduction into a patient is disclosed. The vaporizer directly vaporizes the liquid by introducing the liquid into a vaporizing chamber having an extremely large width to height ratio, i.e. in excess of 600:1. The carrier gas flows in laminar flow through the vaporizing chamber and the liquid anesthetic is introduced at a controlled flow such that it immediately vaporizes upon introduction to the entrance of the vaporizing chamber. A control scheme utilizing a CPU controls the percentage of anesthetic vapor in the outlet gas by sensing certain parameters and then controlling the flow of liquid anesthetic by controlling the speed of a controllable speed pump.

Abstract: A method and apparatus suitable for sweetening sewerage which avoids the need for pumping the sewerage. The method comprises the steps of passing the sewerage under a gas-tight enclosure and causing it to fall as a stream through a first passageway, passing bubbles of a gas, such as oxygen, up through the descending sewerage to dissolve in the liquid stream to form a gas-liquid stream and causing the gas-liquid stream to ascend through a second passageway in which further bubbles of the gas are passed therethrough to dissolve further gas in the stream to balance the liquid density in the descending and ascending streams.

Abstract: A method of rectifying a multicomponent mixture by pressure swing adsorption to separate primary and secondary components of the mixture. Two groups of adsorbent beds are used in the method and adsorbent beds of the two groups are employed in a paired relationship and subjected to feed, co-current depressurization, evacuation, and countercurrent repressurization stages. In the feed stages, pairs of the adsorbent beds are pressurized with the mixture to adsorb the primary component in a first group of the adsorbent beds and in an entry section of a second group of the adsorbent beds. Also during the feed stage, the secondary component is adsorbed in the second group of adsorbent beds in remaining sections thereof. During co-current depressurization, any of the secondary component adsorbed in the first group of adsorbent beds and part of the primary component is driven to the second group of adsorbent beds.

Abstract: An air separation method and apparatus for producing nitrogen is provided in which oxygen enriched liquid, produced as a column bottoms of a distillation column, is partially vaporized and phase separated. The vapor phase is expanded to provide refrigeration while the liquid phase, after pressure reduction, is introduced into the head condenser to condense reflux to the column. Alternatively, part of the oxygen enriched liquid can be fully vaporized and then expanded to provide refrigeration. In such case, another part of the oxygen enriched liquid can be used to condense reflux to the column. Part of the air to be separated is liquefied against the oxygen enriched liquid to be vaporized and then introduced into a lower portion of the column to maintain production and purity levels that would have been obtained had all the oxygen enriched liquid stream been used in condensing reflux to the column.