Abstract: A support plate, together with the shell of an aluminum holding and/or refining vessel, in combination with a refractory sheet positioned on the inner wall of a graphite block in which a heating element assembly is positioned, is used to hold and seal the heating assembly against exposure to air, without the need for enclosing the heating elements in a metal heating element container.

Abstract: Feed air to a prepurifier adsorption system/cryogenic air separation system for dry, high purity nitrogen and/or oxygen production is dried in a membrance dryer preferably characterized by a countercurrent flow path. Drying is enhanced by the use of purge gas on the permeate side of the membrane dryer, with adsorption system or cryogenic air separation system product or waste gas, dried feed air or ambient air being used as purge gas. Two membrane materials are employed in the membrane dryer, in a single stage or in two stages, for enhanced removal of water and carbon dioxide from the feed air.

Abstract: A high efficiency gas dissolution system is used to dissolve gas in a portion of a body of liquid, improving gas utilization and reducing associated energy requirements. A portion of the body of liquid is recirculated through a mechanical, in-line gas dissolution device wherein a secondary feed gas is dissolved in the liquid.

Abstract: Very high purity nitrogen is produced by air separation in a three stage membrane system in which the third stage permeate is recycled to the second stage and the membrane surface area is distributed between the stages to achieve high product recovery and process performance. Other gas separations, such as argon from oxygen, can likewise be achieved by thus using a three stage membrane system.

Abstract: A duplex adsorption process is carried out in one or more stages, each having a normal bed portion and an inverted bed portion that enables the less selectively adsorbable light component of a fluid mixture to be displaced from the normal bed portion and the more selectively adsorbable heavy component to be displaced from the inverted bed portion. Pressure swing adsorption and thermal swing adsorption processes can be employed.

Abstract: The threaded connection between a graphite shaft and a metal shaft, such as is used to drive a rotating nozzle in the refining of aluminum, is strengthened by coating the graphite surface that contact the flange portion of the metal shaft prior to the fastening of the shafts together. The coating comprises solid material bonded to the graphite surface to form a hard, adherent coating deposited by coating the graphite surface with a solution or colloidal dispersion of the material and drying said solution or colloidal dispersion to leave the solid material bonded to the graphite surface. The coating of the graphite shaft serves to greatly strengthen the threaded connection and the ability of the connection to transmit driving torque from the metal shaft to the graphite shaft.

Abstract: Enhanced air drying or other gas purifications are achieved using purge gas, rather than product gas, to facilitate permeation in membrane systems having substrates adapted to achieve radial mixing and having countercurrent flow patterns and uniform flow of gas over the surface of the membranes.

Abstract: Membrane or pressure swing adsorption systems are used for air separation, with the crude nitrogen stream obtained thereby passing to a catalytic combustion system for reaction of residual oxygen with hydrogen to produce a high purity nitrogen product. Excess hydrogen in the nitrogen product is minimized by controlling the amount of hydrogen employed based on the instantaneous crude nitrogen flow and purity, and adjusting hydrogen ingestion in response to nitrogen product purity feedback. Plant flow rate tracking control limits maximum rates of flow change to ensure stable operation.

Abstract: PSA air separation processes are carried out using low adsorption/desorption pressure ratios, together with special adsorbents capable of desirably adsorbing nitrogen at the upper adsorption pressure level and of readily releasing nitrogen for discharge at the lower desorption pressure level.

Abstract: This invention relates to a method of conducting a joining/coating operation which provides good wetting of metal-comprising substrate surfaces by metal-comprising filler/coating materials while reducing the rate of metal oxide formation. The joining/coating operation is carried out in a controlled oxidizing atmosphere having an oxidation capability greater than that required to oxidize a metal-comprising filler material used for joining or a metal-comprising coating, but having less oxidation capability than that of air. Typically the controlled oxidizing atmosphere consists essentially of nitrogen and oxygen, wherein the oxygen concentration is controlled at a set point. The range of the setpoint corresponds with an oxygen concentration which can range from greater than about 10 ppm to about 100,000 ppm, depending on the application.

Abstract: Multiple bundle fluid separation apparatus having at least two hollow fiber membrane bundles arranged in end-to-end linear series encased in a shell or casing. The bundles are in communication with a core tube and are connected serially in such fashion that one end of one bundle is connected to one end of its adjacent bundle. There is also present an auxiliary permeate tube to convey permeate to a permeate exit port. The casing has appropriate ports for feed inlet, and retentate and permeate outlets.

Abstract: Semipermeable membranes comprised of certain sulfonated substituted polysulfone polymers containing the polymer repeat unit (A) or (B) as herein defined. The invention also pertains to processes for using said membranes for the selective permeation of at least one gaseous component from a mixture of gases containing said gaseous component in admixture with other gaseous components.

Abstract: Process for the dehydration of gases using composite permeable membranes, preferably hollow fiber composite membranes comprised of a porous support coated with an ultrathin layer of a defined sulfonated polysulfone or sulfonated polyether ketone. The processes also contemplate the use of a sweep or purge gas on the water-enriched permeate side of the composite membrane to increase the efficiency of the dehydration process.

Abstract: Gas distribution system including main, lateral and loop conduits in which gas flow is continuously provided between a source of pressurized gas and venting means so that "dead space" is avoided in the distribution system and continuous real time monitoring of system gas is enabled.

Abstract: The dispersion of a gas in a liquid is enhanced by the use of an adjustable conical mixer to control the flow of a gas/liquid mixture to a venturi device used to accelerate the mixture to a supersonic vclocity with subsequent deacceleration to subsonic velocity to produce sonic shock waves in the mixture.

Abstract: Permeable membranes comprised predominantly of specifically defined tetrabromobisphenols and aromatic dicarboxylic acids. The invention also pertains to the novel permeation processes for recovery of an oxygen/nitrogen or carbon dioxide/methane component form a mixture of said component with other components.

Abstract: A pressure swing adsorption process and system for air separation includes a variable volume nitrogen product storage vessel, which is monitored to determine variations in user product demand. The processing cycle and individual processing steps are adjusted during periods of reduced demand to maintain a desired product purity and pressure, with power reduction and energy savings being achieved under turndown conditions.

Abstract: A fluid separation device comprising an annular hollow fibers bundle in a shell having four ports, a fluid entrance port, a sweep fluid entrance port, a nonpermeate exit port and a sweep fluid-permeate exit port, wherein said bundle is encased in an essentially nonpermeable film barrier.

Abstract: A gas-liquid mixing process and apparatus employing two or more stacked impeller-draft tube assemblies adapted to enable effective gas ingestion into a recirculating body of liquid by vortex development to be continued upon an appreciable variation in liquid level during the course of the mixing operation.

Abstract: Composite semi-permeable membranes comprised of an extremely thin layer of a sulfonated polysulfone polymer coated on a porous support are useful in processes for the selective permeation of ammonia from a mixture of gases containing the ammonia component in admixture with other gaseous components.