Abstract: The invention relates to a process for laser welding at least one metal workpiece (1) by a laser beam (3), said workpiece having a surface coating (2) containing aluminium, characterized in that the laser beam (3) is combined with at least one electric arc (4) so as to melt the metal and actually weld said workpiece(s).

Abstract: A method of treatment of a gas mixture which contains H2, H2S and possibly of other impurities, such as hydrocarbons. The treatment method is aimed at purifying the hydrogen mixture without incurring a overall pressure loss. The method according to the invention uses a device for pressure swing adsorption where the device includes an integrated compressor. In each adsorber of the device a pressure swing cycle is carried out which includes the steps of: adsorption, decompression, purge, and repressurization.

Abstract: The invention concerns an oxide ion conductive ceramic membrane, characterized in that it comprises a non-null finite volume with non-null total thickness E, comprising a dense layer (CD) of a solid electrolyte, a so-called bonding layer (CA), of two porous electrodes (EP) and (EP?), two porous current collectors (CC) and (CC?), and at least at least a coating porous layer (ER), characterized in that the thickness E of the volume of said membrane, is equal to the sum of the thickness of each of said elements. The membrane is used for separating oxygen from air or from a gas mixture containing same.

Abstract: The invention relates to an exchanger, advantageously a plate exchanger, comprising counter-current parallel exchange sections (8,9). According to the invention, the exchange section for the water (8) has an essentially constant cross-section, whereas the exchange section (9) for the cryogen has a reduced inlet region (9a) enabling the possible formation of ice (10) in the water passage (8) to be concentrated on a small volume, without blocking said water passage. The invention can especially be applied to the supply of gaseous hydrogen stored in a liquid form to an on-board power generating device in a vehicle.

Abstract: A process and an apparatus for separating air by cryogenic distillation. The apparatus has a medium pressure column thermally coupled to a low pressure column. Compressed and purified air is cooled to cryogenic temperature in an exchanger, and sent at least partly to the medium pressure column. Streams enriched in oxygen and nitrogen are sent from the medium pressure column to the low pressure column and, streams enriched in nitrogen and oxygen are removed from the low pressure.

Abstract: A gas generator assembly, which is especially suited to both transportable and on-board oxygen generators, with at least one adsorbent and a buffer tank to store product gas separated from a feed gas mixture. In order to make the assembly squat and compact, the buffer tank may be of an annular or quadruple U shaped configuration. Such a buffer tank configuration may also provide the assembly with improved structural and protective attributes.

Abstract: A method which include an air intake into an air separation unit; extracting from the separation unit at least a gas stream, essentially consisting of an air gas, in particular oxygen or nitrogen, and directing one or more of these gas streams towards the combustion chamber of a gas turbine; controlling at least one parameter related to the or each gas stream, by acting on a compressor in each gas stream arranged downstream of the air separating unit; assigning to one or more parameter a variable setpoint value, based on a value representing the load of the gas turbine.

Abstract: Methods for hybrid laser/MIG welding processes. A bevel formed between the edges of material to be welded together is partially filled with molten metal. The molten metal is delivered in the form of a filler wire, which is melted by a combined electric arc and laser beam. The welding speed is at least 2 m/min, the filler wire feed speed is at least 20 m/min and the filler wire diameter is less than 1.2 mm.

Abstract: An integrated air separation and oxygen fired power generation system includes an air separation unit and a gas turbine including an air compressor to provide compressed air for the air separation unit. The system further includes a gas turbine expander and at least one additional turbine to drive the air compressor, as well as at least one combustion unit to provide drive gas for expander and additional turbine(s). A portion of oxygen produced by the air separation unit is delivered to the combustor(s) to facilitate production of drive gas for use by the expander and additional turbine(s). Turbine inlet temperatures are controlled by recycling water or steam to the combustor(s).

Abstract: An apparatus and method for producing products using a fluid, which enables one to control the quality of the fluid from the point of production to the point of use, monitored on a microbiological, physical, and chemical basis. At least one sensor for the acquisition of purity information and a system for storing such purity information is included.

Abstract: An integrated cooling apparatus and process which includes a source of compressed gas; a cooling unit for cooling the compressed gas to form cooled compressed gas by heat exchange with water having a first purity, thereby producing a stream of cooled compressed gas and a stream of warmed water having the first purity; a first heat exchanger for warming a stream of water having a second purity, the second purity being lower than the first purity, by indirect heat exchange with a stream of water having the first purity; and a conduit for sending cooled water having the first purity to the cooling unit.

Abstract: A method and an apparatus for enriching a combustible gas. The gas mixture is initially flowing in a distribution line at a set pressure. Part of the mixture is bypassed to a separate line where it is then compressed. This compressed stream is then treated in a gas separation unit and is injected back into the distribution system at about the set pressure.

Abstract: An apparatus and process for producing pressurized gaseous product by air separation. A compressed air stream is cooled in an exchanger to form a compressed cooled air stream. The stream is then cryogenically compressed in a first compressor to form a first pressurized gas stream. The first pressurized gas stream is further cooled in the exchanger, cryogenically compressed in a second compressor, and then it is cooled and partially liquefied. The cooled and partially liquefied product is then fed to a system of distillation columns. A liquid product is removed from the system of distillation columns. This product is then pressurized, vaporized and warmed in the exchanger to yield pressurized gaseous product.

Abstract: The invention concerns a method for using an installation for delivering a frozen product comprising a feed line connected to a storage container or to an installation producing said frozen product. Prior to introducing said product into said feed line or during an interruption in the operation of said installation, a cold fluid is circulated in said feed line bringing the feed line to a temperature capable of maintaining said product frozen during its stay in said feed line or of maintaining said channel at said temperature. The invention also concerns an installation for delivering a frozen product and a delivery feed line. It comprises means for circulating a cold fluid in said feed line from a point located proximate to one of its ends. The invention is applicable to the food industry.

Abstract: Process and apparatus for cooling a compressed gas stream which utilizes one or more elongated vessels having a substantially vertical orientation. Each vessel has one compartment for indirect heat exchange between the compressed gas stream and a cooling stream and a second compartment for direct contact between the compressed gas stream and a liquid stream. The two compartments are separated by a barrier, which allows for upward passage of air, but prevents the downward passage of liquid. The design permits one to use the heat present in the compressed air efficiently.

Abstract: A method and a device for cooling a mass of meat-, tissue-, vegetable- and/or fruit-containing substance in a container, in particular a mixer, blender or mill, using liquefied nitrogen (N2) which is supplied in the lower region of the container at a constant working pressure via at least one nozzle. During the cooling process and/or in stoppage times, the nitrogen is briefly supplied to the nozzle or, via the latter, into the container by means of at least one pressure pulse that is increased in relation to the working pressure. The pulsed supply of pressurized nitrogen blows blocked and/or iced-up nozzles free again and thus ensures a more reliable operation of cooling a mass of a substance. This method and device are suitable, in particular, for use in foodstuff technology.

Abstract: Methods and apparatus for determining the NOx content in a combustion flue gas. Several parameters of the combustion process are measured in the combustion furnace. These parameters are then input to a neural network, which then, based upon the input data, generates output data representative of the concentration of NOx in the flue gas. This result is determined without the use of physical NOx sensors.

Abstract: The invention concerns a treatment method which consists in using a pressure swing adsorption treatment unit (16) and causing said treatment unit (16) to follow a nominal operating cycle, based on nominal operating conditions and in order to ensure minimal performances of the feed gas treatment. It further consists in providing at least a pre-programmed auxiliary operating cycle, different from the nominal cycle, and, when the operating conditions differ from the nominal conditions to the extent that the treatment unit (16) no longer achieves its minimal performances, in imposing to the treatment unit (16) to follow the or one of the auxiliary cycles.

Abstract: A process for the separation or concentration of olefinic hydrocarbons from mixtures of olefinic and paraffinic hydrocarbons uses a polyimide membrane. The process is well suited to separating propylene from propylene/propane mixtures. The novel method The membrane exhibits good resistance to plasticization by hydrocarbon components in the gas mixture under practical industrial process conditions.

Abstract: This disclosure discusses problems associated with using natural gas to produce a variety of synthetic hydrocarbon products by production processes that require syngas feedstocks with varying H2/CO and (H2?CO2)/(CO+CO2) ratios. A number of gas separation membranes are used to vary the composition of the feed streams to different hydrocarbon synthesis units so that different synthetic hydrocarbon products can be produced. The process supplies syngas to an integrated hydrocarbon processing system comprising a number of hydrocarbon synthesis units. Gas (usually a portion of a raw syngas stream) is routed through the separation membrane units, multiple H2-rich and H2-lean streams are produced. These H2-rich and H2-lean streams can then be combined in a controlled fashion to produce feed streams of the desired compositions for the various hydrocarbon synthesis units. A variety of liquid synthetic hydrocarbon products can be produced from a given syngas source as required by market demands.