Abstract: An ultra-high purity nitrogen generating method comprises: feeding feed air to a carbon dioxide eliminator-drier and a primary rectification column, thereby removing catalyst poisons for an oxidation catalyst used for oxidation of carbon monoxide and hydrogen in the feed air by means of the carbon dioxide eliminator-drier and the primary rectification column, condensing and liquefying a part of low purity nitrogen gas separated in the primary rectification column by means of a condenser, warming the raw nitrogen gas which has not been condensed and liquefied in the condenser to normal temperature by means of a heat exchanger and compressing it by a recyclic compressor so that the pressure thereof is increased and the temperature thereof is raised, oxidizing carbon monoxide and hydrogen in an oxidation column and removing the resulting carbon dioxide and water by an adsorption column.

Abstract: Process for preparing ultra-pure nitrogen containing less than 100 ppb (parts per billion) impurities, characterized in that at least the impurities consisting of carbon monoxide (CO) and/or hydrogen (H.sub.2) are removed by passing the gas from which at least one of these two components has to be removed, over a bed of particles including a metallic element namely copper (Cu) and/or ruthenium (Ru) and/or rhodium (Rh) and/or palladium (Pd) and/or osmium (Os) and/or iridium (Ir) and/or platinum (Pt) supported on a particulate support, by the technique of ion exchange and/or by the technique of impregnation. This technique enables to produce ultra-pure nitrogen by using it either with nitrogen obtained by distillation, or air to be distilled as an additional step for the removal of CO.sub.2 and H.sub.2 O. A device for carrying out the process constitutes another object of the invention.

Abstract: A process for producing disilane from monosilane comprising introducing monosilane into a reaction zone in which the monosilane is subjected to an electric discharge generated by a high frequency current. The monosilane is mixed with at least one inert gas selected from the group consisting of helium and argon. The pressure of the gaseous mixture in the reaction zone is between 0.1 and 3 bar, and the gaseous mixture is contacted in the reaction zone under electric discharge with a wall cooled to a temperature which is sufficiently low for the saturation vapor pressure of the disilane to be negligible, but not low enough for the monosilane to condense at the working partial pressure. Apparatus for conducting this process is provided.

Abstract: Auxiliary gas is withdrawn from the heat exchanger during cooling or reheating at an intermediate temperature which is close to the vaporizing temperature of the oxygen or nitrogen high pressure product stream, then compressed by a cold compressor and reintroduced in the heat exchanger. The invention is particularly applicable to the production of gaseous oxygen at a pressure greater than about 15 bar.

Abstract: An assembly comprising an intermediate volume of medium-pressure gas (8) in a transportable housing (3) which is advantageously combined with a user apparatus (4) and selectively connectable to a high-pressure gas supply (1) by coupling it to a filling unit (2) via a quick connection system (15, 16). The assembly is particularly useful in portable welding apparatuses.

Abstract: Process and installation for the production of a variable flow rate of at least one principal constituent of air under pressure, of the type in which the constituent is withdrawn in liquid phase from an air distillation apparatus (12), tills liquid is brought to a vaporization pressure, and the liquid is vaporized under this vaporization pressure by heat exchange (in 9; 25) with a calorigenic fluid under pressure. The flow rate of the product constituent is adjusted by modifying the flow rate of the liquid to be vaporized and the vaporization pressure. The vaporization pressure is intermediate the withdrawal pressure and the production pressure, and the gas resulting from the vaporization is compressed to the production pressure (in 20).

Abstract: A process for supplying nitrogen to at least two user stations, whose requirements as to nitrogen purity are different. Compressed air is passed from an air compressor (12) to at least one air treatment station (13) permitting effecting at least one of the following treatments of oil removal, filtering out a major portion of the particles, drying, and bringing the air to the desired temperature. The compressed air is then sent to a centralized gas separation unit (14), so as to produce at the outlet of the unit impure nitrogen of intermediate purity. The gas from the centralized separation unit (14) is directed to at least two utilization lines (3-5), each comprising a local gas separation unit (6-8), in which the gas is again treated, so as to obtain at the outlet of each local separation unit nitrogen of a purity suitable for the uses of each of the user stations (9, 10) at the end of the line.

Abstract: Ultra-high purity nitrogen is generated by feeding feed air to a carbon dioxide eliminator-drier and a primary rectification column, thereby removing catalyst poisons for an oxidation catalyst used for oxidation of carbon monoxide and hydrogen in the feed air by the carbon dioxide eliminator-drier and the primary rectification column. A part of low purity nitrogen gas separated in the primary rectification column is condensed and liquefied by a condenser. The raw nitrogen gas which has not been condensed and liquefied in the condenser is warmed to normal temperature by a heat exchanger and compressed by a recyclic compressor so that the pressure thereof is increased and the temperature thereof is raised. Carbon monoxide and hydrogen are oxidized in an oxidation column and the resulting carbon dioxide and water are removed by an adsorption column.

Abstract: A first MFC 10 and a second MFC 10A are disposed respectively on a silane gas feed line 5 and an inert gas or other dilution gas feed line 19 for feeding a gas for semiconductors such as silane gas or an inert gas or other dilution gas to a mixing chamber 13. A buffer tank 21 is provided which restrains or relieves the pressure energy of the mixed gas coming from the mixing chamber 13 and supplies the same mixed gas to each of a plurality of semiconductor manufacturing units 4 separately. The first MFC 10 and second MFC 10A are actuated to open or close on the basis of an increase or decrease in the pressure value of the mixed gas stored in the buffer tank 21, thereby stopping or starting the feed of the silane gas and the inert gas or other dilution gas again.

Abstract: The installation comprises an insulated storage tank (1) containing the gas in at least partially liquid form at a high pressure, a line (2) comprising a vaporizer (3) for supplying gas to a user station (A), a first cold-holding circuit (4), comprising a valve (5) and a first exchanger (6) in heat-exchange contact with the fluid in the first tank (1), and a pressure-holding line (8) comprising a second exchanger (9) and a valve (10). The system is particularly useful as a backup installation for a main gas-production source (30).

Abstract: All the entering air is brought to a high pressure and then cooled to an intermediate temperature. At this temperature, a portion of the air is work expanded (in 4) to the medium pressure, and the rest is liquified. The low pressure column operates under a pressure of the order of 1.7 to 5 bars absolute, and its residual gas is expanded in a second turbine (9) after having been reheated to ambient temperature, then further heated (in 7) by heat exchange with the compressed air. Use for the production of impure oxygen under pressure and simultaneously at least one liquid product.

Abstract: Air distillation installation comprising: (A) an air compressor group (1) whose output is connected to an outlet coupling (11); (B) two cylinders (2A, 2B) for the purification of air by adsorption having inlet/outlet couplings (12A, 12B); (C) a first framework (13) in which are mounted: (a) the accessories downstream of the compressor such as an assembly (14, 17) for precooling air; (b) accessories of the purification cylinders, such as an assembly of valves and a regeneration gas reheater (18); and (c) the connection conduits of the mentioned accessories, with their safety members and their automatic and/or remotely controlled valves, these conduits terminating in couplings (15, 22A, 22B, 23) for connection to other portions (1, 2A, 2B, 4) of the installation, and the corresponding monitoring, control and instrumentation members (21); (D) a second framework (31) in which are mounted: (d) the principal heat exchangers (24) and the subcoolers (25); (e) the assembly of the cold accessories such as the cryogenic

Abstract: Apparatus for the formation of excited or unstable gaseous molecules, comprising a tubular gas passage (5) having an axis, formed between a first electrode (1) and a dielectric tube (3) coaxial to the first electrode and supporting a second electrode (4), the electrodes being connected to a high voltage high frequency source (13). The first electrode (1) surrounds the dielectric tube (3) and comprises an elongated gas inlet (7) and outlet (8) parallel to the axis and diametrically opposed to each other on opposite sides of the dielectric tube (3). The second electrode (4) is a layer of metal applied to the internal wall of the dielectric tube (3). The second electrode (4)is formed by metallization of the internal wall of the dielectric tube (3). The gas inlet (7) and outlet (8) have a height not exceeding the radial thickness (e) of the gas passage (5). The external wall of the dielectric tube is covered with a thin layer (21) of enamel.

Abstract: A process for the treatment of objects with an inflammable volatile liquid, in an installation comprising at least one upwardly open tank (16) adapted to be filled with the liquid, a drying device (20) adapted to remove contained treatment liquid from the treated objects, and a transport system adapted to bring an object to be treated above the tank, and to immerse it in the tank, to withdraw it, and to transfer it into the drying device, then to remove it. The tank and the drying device are disposed in a closed chamber (2, 4) containing an atmosphere comprised principally of a protective gas, with an oxygen content maintained sufficiently low that the ignition of the treatment liquid will be impossible. This chamber is separated from the exterior by at least one gas lock (1, 5) containing the same atmosphere. The object to be treated passes through the gas lock to enter the chamber and by the same or another gas lock to be removed.

Abstract: The invention concerns a process for freezing an article, such as a food according to which said article is contacted with the surface of a porous support which is impregnated with a cryogenic liquid. The invention also concerns a device for freezing an article including a conveyor of porous material, which is insulated by means of an enclosure as well as means for impregnating said conveyor with a cryogenic liquid.

Abstract: In this process having two turbines and at least two stages for compressing the cycle gas, the two turbines are fed at the same intake pressure, the cycle gas is expanded in the warm turbine down to a first exhaust pressure, and the cycle gas is expanded in the cold turbine down to a second exhaust pressure lower than the first exhaust pressure.

Abstract: A self-contained device for the supply of energy to an apparatus (7) driven by gas under pressure, comprises a portable reservoir (1) of cryogenic liquid, and structure associated with the reservoir to withdraw and vaporize liquid from the reservoir and to send it to the apparatus (7). Two circuit portions (2.sub.1, 2.sub.2) incorporate vaporizers (5.sub.1, 5.sub.2) and are delimited between non-return valves (4.sub.1, 4.sub.2) upstream and control valves (6.sub.1, 6.sub.2) downstream. When open, the control valves drive the apparatus (7). The reservoir (1) is of the double wall type (1.sub.1, 1.sub.2), at least one upstream part of the circuit portion (2.sub.1, 2.sub.2) being disposed between these walls (1.sub.1, 1.sub.2). The two circuit portions are in parallel (2.sub.1, 2.sub.2) and the respective valves (6.sub.1, 6.sub.2) are sequentially controlled by a control device (9, 12) which is sensitive to the pressure (P.sub.1, P.sub.2) prevailing in the circuit portions (2.sub.1, 2.sub.2).

Abstract: A rotary device including a plurality of vertical prismatic sectors mounted on a first annular plate comprising two arrays of gas passages which communicate with the outer and inner collectors of respective sectors, and interacting with a second plane annular plate on a housing defining a set of inner chambers. The second plate comprises two concentric arrays of apertures which communicate with corresponding chambers in the set of chambers, and are spread out along the path of the two gas passage arrays of the first plate. The device is particularly useful for producing oxygen.

Abstract: A membrane nitrogen generator exhibiting increased flexibility and productivity in response to changes in customer demand which entails a membrane generator capable of generating nitrogen of variable flow rate and purity, bulk storage capacity for storing nitrogen of a purity which is higher than that required by a customer and flow and purity controllers for delivery to a customer plant.

Abstract: A process and installation for the separation of air in a cryogenic distillation apparatus (24) comprising a distillation column (30, 42) and in which the supplied air is separated to produce a fraction rich in oxygen and a fraction rich in nitrogen as products. The purities of these products are maintained substantially constant during variations of demand of either product or of the flow rate or of the pressure of the supplied air by introducing an excess of liquid rich in nitrogen into the distillation apparatus when the demand for the product or the flow rate of the supplied air increases, and by withdrawing an excess of liquid rich in nitrogen from the distillation apparatus, and storing this liquid, when the demand for the product or the flow rate of the supplied air decreases.