Abstract: The invention relates to a process for the dry surface treatment of at least one metal surface portion, according to which the portion is treated at a pressure close to atmospheric pressure by a gaseous treatment atmosphere comprising excited or unstable species and substantially devoid of electrically charged species, obtained from a primary gaseous mixture and if necessary an adjacent gaseous mixture, the primary gaseous mixture being obtained at the gas outlet of at least one device for the production of excited or unstable gaseous species, in which an initial gaseous mixture comprising an inert gas and/or a reducing gas and/or an oxidizing gas has been converted, the adjacent mixture not having passed through the device.

Abstract: A method and an associated apparatus for cleaning an inner wall of a mold part includes forming a chamber between displaced mold parts by introducing a casing between the mold parts. The casing enclosures a blasting device for introducing a blasting nozzle which directs a cleaning jet at the inner wall. The chamber encapsulates noise and particles which are produced during the cleaning process.

Abstract: A device for confining leaks of one or more gases contained in a gas cylinder, which comprises a shroud made of a flexible and nonflammable material which is inert with respect to the gas or gases contained in the cylinder and designed to partially envelope said cylinder, wherein said shroud has an opening provided with means for sealing said shroud to the surface of the cylinder and wherein the shroud is provided with an outlet coupling connected to a line for removing one or more of the gases to a means for neutralizing said one or more gases.

Abstract: A method for purifying liquefied corrosive gases of metallic impurities is described. The principle for this purification method relies on vapor-phase transfilling the vapor phase from a source container into a receiving container. This method has been observed to decrease metal concentrations by a factor of at least 1000 and decreases the metallic impurity levels in the resulting condensate. The vapor transfer is accomplished by controlled differential pressure rather than mechanical pumping, thereby generating no particle or metal impurities.

Abstract: Provided is a process for the preparation of an ultrapure hydrogen peroxide solution to be purified through at least one bed of anion-exchange adsorbents and at least one bed of cation-exchange adsorbents. The at least one bed of anion-exchange adsorbents contains carboxylate ion of formula R--COO.sup.- in which R represents a hydrogen atom, an aryl radical containing from 6 to 10 carbon atoms or an alkyl radical containing from 1 to 4 carbon atoms. The aryl and alkyl radicals are either unsubstituted or substituted by one or more fluorine atoms. A first bed of the at least one bed of anion-exchange adsorbents through which the solution to be purified passes is a bed containing carboxylate ions of formula R--COO.sup.-. Also provided is a plant for the implementation of the inventive process.

Abstract: A cryogenic air separation process and apparatus in a distillation column having a top condenser. Air is compressed, purified and cooled to a temperature suitable for distillation. The air is separated in a distillation column so that an oxygen-enriched liquid and a nitrogen-enriched gas are produced within the column. A stream of cryogenic liquid is sent to the column and an oxygen-enriched liquid is sent from the column to the condenser. The flow rate of cryogenic liquid is regulated as a function of the level of oxygen-enriched liquid at the bottom of the column, and a product stream is withdrawn from the column.

Abstract: Heat and material exchange device including a stack of fixed ventilators to promote gas mixing, each ventilator being constituted by four deflectors whose mean normals are inclined and generated one after another by rotation about vertical axes, the sum of the four angles of rotation being 360.degree.. The ventilators are stacked in successive horizontal layers amidst which each deflector forms a part of two adjacent ventilators turned in opposite directions and such that there is sufficient space between two adjacent deflectors for the passage of gas. The deflectors are pierced by at least one hole so as to promote passage of the liquid to the underside of the deflectors. At least some of the deflectors are connected to at least one of their neighbors in a same horizontal plane by a common edge segment so as to permit lateral division of the liquid between deflectors.

Abstract: A deposit of a silica base layer is formed on the surface of a glass product by projecting on a hot surface of the product, in a non confined ambient atmosphere, a gaseous mixture having a silane content lower than 2%, an oxygen content between 3.5 and 30%, and advantageously a hydrogen content lower than 5%. The surface of the object to be treated is advantageously heated immediately before being sent to the injection station.

Abstract: The invention relates to a method of inflating a tire comprising the steps of:providing a tire mounted on a rim, said tire comprising a tire valve to allow selective inflation or deflation of said tire, said tire being filled with a certain amount of air;deflating said tire to reach a pressure which is less than or equal to a predetermined low pressure, said predetermined low pressure being lower than atmospheric pressure;inflating said tire with a source of inert gas to reach a pressure at least equal to a pressure greater than atmospheric pressure, to obtain inside said tire a gas mixture comprising between 5% O.sub.2 by volume and 0.5% O.sub.2 by volume.It also relates to a tire evacuation apparatus specially adapted thereto.

Abstract: Methods of increasing the throughput of recovery boilers equipped with at least two levels of injection of air, the methods improving the thermal efficiency of the boiler with oxygen enrichment of the air in at least one level of the combustion air system, at or above the secondary air level. In one method, a black liquor recover boiler having two levels of air injection is retrofitted with a third level of oxidant injection below or at the same level as the original secondary air, and oxygen enrichment is applied to at least the original secondary air stream and the third level air stream. A preferred method is for the third level to be placed at or close to the same level as the black liquor injector ports.

Abstract: Provided is a process for purfying a gas. In the process, the gas to be purified flows through a hollow dielectric tube. An electric field in the gas to be purified is created by a traveling electromagnetic wave which travels in the dielectric tube and is suitable for creating, in the gas, an atmospheric-pressure plasma which is not in local thermodynamic equilibrium, for the purpose of dissociating impurities in the gas in order to form reactive compounds. The formed reactive compounds are reacted with a corresponding reactive material for eliminating the reactive compounds from the gas to be purified.

Abstract: A process for the generation of energy and of a hydrogen-rich mixture (30), includes the following steps:a) a partial oxidation of an incoming hydrocarbon gas mixture (15) is carried out using an oxidant mixture (16) which contains oxygen, so as to obtain as output from the unit a reaction gas (17) which contains hydrogen and CO;b) the reaction gas produced at the end of step a) is passed into a membrane separator (24) which generates, as its permeate output, a permeate gas mixture (25) enriched in the more permeable components of the reaction gas and, as its retentate output, a retentate gas mixture (26) enriched in the less permeable components of the reaction gas;c) the retentate gas mixture (26) is treated in an electricity generation unit (27);d) the permeate gas mixture (25) is separated in a preferential adsorption separator (29) so as to obtain, as unadsorbed product gas, the desired hydrogen-rich gas mixture (30).

Abstract: Heat-treatment device which includes a cooling unit comprising delivery nozzles which deliver at least one coolant, characterized in that it furthermore comprises a shielding element designed so as to maintain a gaseous shielding atmosphere around at least part of the delivery nozzles.

Abstract: Provided is a process having an increased production capacity for nitric acid, which moves can be operated safely and efficiently. The process comprises forming a reaction mixtures by mixing air, ammonia, oxygen and an inert cooling fluid, preferably water, and then reacting the ammonia with oxygen in a reaction zone to form nitric oxide. The amount of inert cooling fluid in the reaction mixture is sufficient to control the temperature of the mixture and maintain the ammonia percentage below the lower explosion limit for the mixture. The nitric oxide produced in the reaction zone is then oxidized to nitrogen dioxide and its dimer, with additional oxygen being introduced into the process for oxidizing the nitric oxide. The nitrogen dioxide and its dimer is then reacted with water to form the nitric acid.

Abstract: A burner assembly having improved flame length and shape control is presented, which includes in exemplary embodiments at least one fuel fluid inlet and at least one oxidant fluid inlet, means for transporting the fuel fluid from the fuel inlet to a plurality of fuel outlets, the fuel fluid leaving the fuel outlets in fuel streams that are injected into a combustion chamber, means for transporting the oxidant fluid from the oxidant inlets to at least one oxidant outlet, the oxidant fluid leaving the oxidant outlets in oxidant fluid streams that are injected into the combustion chamber, with the fuel and oxidant outlets being physically separated, and geometrically arranged in order to impart to the fuel fluid streams and the oxidant fluid streams angles and velocities that allow combustion of the fuel fluid with the oxidant in a stable, wide, and luminous flame. Alternatively, injectors may be used alone or with the refractory block to inject oxidant and fuel gases.

Abstract: A process for recovering olefins from a cracking effluent containing olefins and hydrogen. The process comprises compressing the cracking effluent in at least one compression stage to form a compressed cracking effluent, contacting the compressed cracking effluent with a membrane at conditions effective to obtain a permeate stream rich in hydrogen and a retentate stream depleted in hydrogen, and introducing the permeate stream into a pressure swing adsorption system at conditions effective to obtain a nonadsorbed stream rich in hydrogen and a desorbed stream comprising olefins.

Abstract: The tap/pressure regulator assembly, advantageously housed in a streamlined cowl forming a bottle-handling bonnet (C), comprises a body (1) intended to be mounted on a gas bottle and defining, on the inside, a gas utilization circuit, going to an outlet (3) via an isolating valve actuated by a lever (5) and via an adjustable pressure regulator (4, 25), and an independent filling circuit going from a filling fitting (6). The body (1) also carries high-pressure and low-pressure pressure gauges (8).Application especially to welding gases.FIG. 2 to be reproduced.

Abstract: An installation for monitoring an apparatus for generating atmospheres. The installation includes a measuring device for measuring at least one parameter representing the actual operation of the apparatus, an evaluator for evaluating the drift of each representative parameter over time and a trigger for triggering an intervention on the apparatus as a function of the drift before values of each representative parameter reach predetermined critical values.

Abstract: A burner assembly having improved flame length and shape control is presented, which includes in exemplary embodiments at least one fuel fluid inlet and at least one oxidant fluid inlet, means for transporting the fuel fluid from the fuel inlet to a plurality of fuel outlets, the fuel fluid leaving the fuel outlets in fuel streams that are injected into a combustion chamber, means for transporting the oxidant fluid from the oxidant inlets to at least one oxidant outlet, the oxidant fluid leaving the oxidant outlets in oxidant fluid streams that are injected into the combustion chamber, with the fuel and oxidant outlets being physically separated, and geometrically arranged in order to impart to the fuel fluid streams and the oxidant fluid streams angles and velocities that allow combustion of the fuel fluid with the oxidant in a stable, wide, and luminous flame. Alternatively, injectors may be used alone or with the refractory block to inject oxidant and fuel gases.

Abstract: The air distillation double column (1,2) includes an apparatus for vaporizing oxygen and condensing nitrogen which comprises on one hand a running type main heat exchanger (7) which is partially immersed during stoppage of the equipment and on the other hand an auxiliary heat exchanger (20) which alone is responsible for liquid vaporization when the equipment is restarted.