Abstract: This column, of the type having a cross-undulating lining, includes means for returning liquid to the vicinity of the edges of the lining and liquid and gas distribution means which contribute to decrease substantially the height of the column. Application to plants for separating gases from air.

Abstract: A method of adsorption separation of gases of the kind which regenerates the adsorbant by pressure viariation and used two adsorbers, wherein the recompression stage includes at least one recompression stage using the oxygen produced, and a final recompression stage up to the high point of the cycle pressure using air intake without draw-off; and wherein the pressure high-point of the cycle is selected between 1.2 and 2 .times.10.sup.5 Pa and the pressure low-point is selected between 0.3-0.7.times.10.sup.5 Pa, at least the final part of the desorption stage being carried out by pumping. The method is essentially relevant to the production of oxygen.

Abstract: The invention relates to a tundish for the continuous casting of steel having a housing for the injection of gas with a feed tube for gas, the injection housing having an upper wall which is permeable to the gas. Periodically, the injection housing is completely replaced by removing the sealing grout.

Abstract: The process comprises circulation in a vessel containing the germs during a time T.sub.1 a ternary gas mixture comprising about 5% carbon dioxide, between 3.5 and 5% hydrogen; the balance consisting of nitrogen, followed by sealingly closing the vessel containing this gas mixture, advantageously under a slight overpressure, these operations are carried out automatically by means of an assembly comprising a gas feeding line and a gas outlet line each provided with an electro-valve and being electronically controlled.

Abstract: To heat a thermic enclosure, flames are generated in a burner having a plurality of injectors, from an oxy-combustible mixture, the flames extending in different directions and having different power and/or oxidizing reducing capacity. Application for example to the heating of furnaces or metallurgical ladles or glassware furnaces.

Abstract: This process is of the alternating type. When the demand of oxygen is lower than the mean value, additional liquid oxygen is produced by introducing compressed oxygen, in gaseous form, in the heat exchange line of the arrangement, the flow of liquid nitrogen injected into the double column being reduced in a corresponding manner. It is thus possible to increase the average yield of the arrangement when extracting argon.

Abstract: Substantially all residual oxidizing gas in a treating atmosphere which is inert or reducing, is eliminated by injecting into the atmosphere a gaseous silicon hydride at a temperature between 50 and 1,600.degree. C. and in amount such that the ratio R of the content of hydride to the content of oxidizing gas to be eliminated is within the range of 1.5 to 20. The rapid action of the trace amounts of hydride injected enables one to control with precision heat treatment processes by maintaining the residual oxidizing gas contents below predetermined very low thresholds.

Abstract: The liquefaction process comprises the stages of pre-cooling (3) the gas, of cooling it by heat exchange (6, 7, 8) and by fractional expansion (10, 11), under supercritical conditions, then of expanding it in a turbine (9) which delivers a volume of subcooled liquid (2). The process is especially applicable to the refrigeration of superconductive elements.

Abstract: The article of which the verticality is critical, for example a distillation column disposed in a closed envelope, is associated with an indicator of verticality comprising a suspended mass and a locating ring. The envelope, which contains the various inner articles, is placed on a base by means of supports and its inclination with respect to the base is adjusted by controlling the relative position of the mass with respect to the ring. Application for example to cold boxes for the in situ production of gas from air.

Abstract: In this process for vaporizing a liquid in first ducts, or vaporization ducts, which are opened at top and bottom, of a plate type heat exchanger, by heat exchange with a main calorigenic fluid which circulates in second ducts of the exchanger, additional gas is generated permanently in the lower end part of the first ducts, for example by means of a compartment in which there is a circulation of an auxiliary fluid which is warmer than the main calorigenic fluid. Application to the main vaporizer-condensers of apparatuses for the distillation of air with double column.

Abstract: A gas under pressue is sent to a first compartment of a separation module having permeation membrane, the first modified gas mixture which exits from the first compartment being introduced into the enclosure to constitute therein a controlled atmosphere which is removed and circulated in counter-current in the second compartment of the module towards the discharge orifice of the latter so as to substantially recombine the two gaseous modified mixtues before discharging same thereby increasing the performances of the separation module.

Abstract: To compensate for load losses in a downstream part of a line for supplying gas under controlled pressure through a valve which is controlled by a pick-up upstream of the line, the pressure read by the pick-up is supplied by a pressure intake which is formed in a tube extending in the line and which is angularly orientable with respect to the flow of gas delivered. Application for example to systems of supplying breathing gas to the passengers of an airship.

Abstract: The invention relates to a process for preparing interconnection substrates of hybrid circuits, comprising effecting on a support the deposition of a thick layer of ink or paste based on a non-noble metal, such as copper or other material having a "copper compatible" formulation, by carrying out in succession a preliminary drying for eliminating solvents at a temperature on the order of 100.degree. C. to 150.degree. C., a firing comprising:a) a temperature rise incorporating a stage for eliminating polymer resins,b) a sintering step at a temperature on the order of 600.degree. C. to 1000.degree. C., andc) a timed cooling,the firing being carried out under a substantially inert gas atmosphere (nitrogen and/or argon and/or helium), the atmosphere of the stage for eliminating the polymer resins having a content of water vapor lower than 15,000 ppm, preferably between 1,000 and 10,000 ppm, while the atmosphere for sintering at high temperature has a content of water vapor in any case lower than 1,000 ppm.

Abstract: A metallic oxide catalyst, containing cupric oxide and an amount of one or more of AgO, HgO or CdO effective for enhancing the ability of the catalyst for removing gaseous hydrides from a gas stream.

Abstract: An adsorber having an upright longitudinal extent includes two perforated parallel panels extending within the vessel formed therein and spaced apart defining an adsorbent mass chamber. The adsorbent mass is in two longitudinal parts having a first part of fine particles and a second part of larger particles. The gas to be treated is circulated horizontally between the two perforated panels. This device allows the treatment cycle to be less than 60 seconds with the same or better performance. This adsorber and process are preferably used for the separation of oxygen from air.

Abstract: Process for melting a furnace charge, with post-combustion of the smokes by njecting an oxygenated gas in the furnace atmosphere as a series of jets flowing according to a tangential component in the space between electrodes and cylindrical furnace partition of the furnace, in a direction of injection so as to produce a rotary gas current about the vertical axis of the furnace and preferably in at least two series as two stepped levels to produce gas currents which rotate in opposite directions. Applications to electrical furnaces for the production of steel or ferro-alloys.

Abstract: A device for providing a non-oxidizing atmosphere above a soldering bath in a vat of a machine for wave soldering, includes a hooding assembly closing the vat, an inner space and a conveyor for electronic circuits extending through the inner space. The inner space is separated from the surrounding atmosphere through seals disposed along the path of the circuits. There is structure for providing and maintaining a non-oxidizing atmosphere in the inner space, for example an inert gas or a mixture of inert and reducing gas.

Abstract: Metallization of ceramics of the type comprising depositing a metallic paste based on molybdenum and/or tungsten and manganese on a ceramic substrate and effecting the sintering of the paste in an atmosphere having a predetermiend oxido-reduction potential, with a rise in and a maintenance of a temperature between 1300.degree. C. and 1600.degree. C., then cooling to ambient temperature, with production of an atmosphere by the addition to a pure neutral gas of a quantity of additional oxygen and a quantity of hydrogen at least sufficient to subsequently obtain by catalytic reaction the desired content of water vapour and contingently the excess content of hydrogen.

Abstract: Alkaline aqueous liquid bleaching detergents that remain stable during storage contain monohydrated sodium perborate, a Mg 3.5 SiO.sub.2 magnesium silicate, sodium acid pyrophosphate and a viscosity regulator composed of dialkylether polyethyleneglycol copolymers.The detergents can be used for washing and bleaching at temperatures between 40.degree. and 90.degree. C.

Abstract: A protective structure for a shut-off valve of a transportable toxic gas container having a metallic hood unlockably mounted on the container around the shut-off valve, comprises a cover made of a shock absorbent material, which is unlockably mounted, typically by a hoop, on the hood and entirely closing the latter. The cover includes an inner recess substantially following the outlines of the hood and an end area resting on the area of the container at the base of the hood.