Patents Assigned to L'Exploitation Des
  • Process for diffusing an odoriferous substance
    Patent number: 5716011
    Abstract: A process for diffusing an odoriferous substance placed in a container, as well as a gas mixture comprising an odoriferous substance in gas form and an odorless and breathable gas, placed in a container under a pressure higher than or equal to 5 bars.
    Type: Grant
    Filed: November 9, 1995
    Date of Patent: February 10, 1998
    Assignee: L'Air Liquide, Societe Anonyme Pour L'Etude et L'Exploitation des Procedes Georges Claude
    Inventor: Jean-Paul Barbier
  • Nitrated polyimide gas separation membranes
    Patent number: 5716430
    Abstract: Useful gas separation membranes made from aromatic polyimides which comprise pendant nitro groups incorporated onto the phenyl backbone of the polymer. These polymers may be synthesized by the aryl nitration of the unsubstituted polyimides, or from the condensation reaction of aromatic diamines containing pendant nitro groups with aromatic dianhydrides, and are particularly useful in air separation.
    Type: Grant
    Filed: May 3, 1996
    Date of Patent: February 10, 1998
    Assignee: L'Air Liquide Societe Anonyme Pour l'Etude et, l'Exploitation des Procedes Georges Claude
    Inventor: John Warren Simmons
  • Equipment for gas separation by adsorption
    Patent number: 5716427
    Abstract: The equipment, for example of the PSA type, comprises gas circulation elements for passing the gas horizontally through an adsorbent (3), which comprise, on at least one vertical side of the adsorbent, a gas distribution volume comprising a first subvolume (5; 9) adjacent to the adsorbent, and a second subvolume (6; 10) separated from the first subvolume by a wall provided with passages (40) having cross-sections and/or a distribution which are selected so as to reduce the variations in local flow rate along the adsorbent. The equipment is particularly useful in separating gases from air.
    Type: Grant
    Filed: August 15, 1996
    Date of Patent: February 10, 1998
    Assignee: L'Air Liquide, Societe Anonyme Pour L'Etude et L'Exploitation des Procedes Georges Claude
    Inventors: Philippe Andreani, Christian Monereau
  • Process for producing pressurized oxygen by adsorption
    Patent number: 5713984
    Abstract: The process comprises a regeneration phase including a co-current depressurization step, in order to participate in the repressurization of another adsorber, a countercurrent depressurization down to the low pressure of the cycle without gas intake, and then a countercurrent elution step at the low pressure of the cycle with oxygen taken off from production. The cycle time does not exceed 20 seconds. The process is particularly application to the production of oxygen having a purity greater than 90% with flow rates of 2 to 6 liters/minute for oxygenotherapy.
    Type: Grant
    Filed: May 1, 1996
    Date of Patent: February 3, 1998
    Assignee: L'Air Liquide, Societe Anonyme pour L'Etude et L'Exploitation des Procedes Georges Claude
    Inventors: Andre Monnot, Marie Helene Renaudin
  • Process and device for analyzing traces of impurities in a gas sample by means of a diode laser
    Patent number: 5705816
    Abstract: The invention relates to a process for analyzing traces of at least one impurity in a gas sample, by absorption by the impurity to be detected of a light beam emitted by a semiconductor diode laser, the beam emitted by the diode being split into at least two branched beams, one called the measurement beam which passes through the gas sample to be analyzed in a multipassage cell before being focused onto a measurement photodetector, another branched beam, called the reference beam, being along a reference path and directly focused onto a reference photodetector without encountering the gas sample, in which process the gas sample is at a pressure at least equal to atmospheric pressure, and a modulation of the supply current of the diode has been introduced, which comprises at least one function of the exponential type.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: January 6, 1998
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Catherine Ronge, Fabrice Bounaix, Patrick Mauvais, Frederic Stoeckel
  • Process and device for the evaporation of a liquid flow
    Patent number: 5704228
    Abstract: In a process for liquid evaporation by heat exchange with a gas which condenses, the pressure of the liquid to be evaporated is reduced and it is enriched in a constituent which has little volatility after evaporation. According to an alternative form, the gas to be condensed can be enriched in the constituent which has little volatility.
    Type: Grant
    Filed: March 15, 1996
    Date of Patent: January 6, 1998
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventor: Jean-Pierre Tranier
  • Method for charging powdery heat insulator into a thermally insulated, double-shelled tank
    Patent number: 5702655
    Abstract: Provided is a method for charging a powdery heat insulator into a thermally insulated, double-shelled tank between its inner vessel and outer vessel. The method comprises causing a powdery heat insulator to flow together with water into a space between the inner vessel and outer vessel of a thermally insulated, double-shelled tank, discharging the water in said space, and then drying the powdery heat insulator. The pressure in the space is then also reduced. The drying of the powdery heat insulator can be carried out by heating either the inner vessel or outer vessel, or both of these vessels, or by inert gas flow, such as nitrogen gas.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: December 30, 1997
    Assignee: L'Air Liquide, Societe Anonyme pour L'Etude et L'Exploitation des Procedes Georges Claude
    Inventor: Toshiro Kato
  • Process for generating nitrogen for heat treatment
    Patent number: 5695731
    Abstract: A process for generating a nitrogen-based gas, comprising the steps of:(i) combining a secondary reducing gas including at least one reducing gas with a primary nitrogen gas including 0.5-5% by volume of oxygen, the combining of the secondary gas being performed according to an uncontrolled all-or-nothing method;(ii) reacting the primary gas and the secondary gas in a catalytic deoxygenation reactor so as to obtain a nitrogen-based reaction gas which includes water vapor; and(iii) removing at least a part of the water vapor present in the nitrogen-based reaction gas by cooling the reaction gas under pressure to induce formation of a liquid phase and then extracting the liquid phase from the reaction gas under pressure to obtain a purified reaction gas.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: December 9, 1997
    Assignee: L'Air Liquide, Societe Anonyme Pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Didier Domergue, Yannick Rancon
  • Method of disinfecting fresh vegetables by processing the same with a liquid containing a mixture of argon:carbon dioxide
    Patent number: 5693354
    Abstract: A method of washing one or more fresh vegetables, which entails washing the one or more fresh vegetables with at least one aqueous liquid containing at least an antimicrobially effective amount of dissolve carbon dioxide, and at least an amount of dissolved argon effective to inhibit bleaching and oxidizing effects of carbon dioxide.
    Type: Grant
    Filed: May 1, 1996
    Date of Patent: December 2, 1997
    Assignees: L'Air Liquide, Societe Anonyme pour L'Etude et, L'Exploitation des Procedes Georges Claude, American Air Liquide Inc.
    Inventors: Kevin C. Spencer, Edward F. Steiner
  • Process for the removal of an impurity contained in a composite gas
    Patent number: 5693302
    Abstract: A process for the substantial removal of at least one of the carbon monoxide and hydrogen impurities contained in a composite gas, according to which:(a) at least one of the carbon monoxide and hydrogen impurities contained in the composite gas are reacted with oxygen, in contact with a catalyst comprising particles of at least one metal chosen from the group consisting of gold and palladium, these particles being supported by titanium dioxide, in order respectively to form carbon dioxide and water;(b) optionally, the carbon dioxide and the water formed are removed from the composite gas;(c) the composite gas, substantially free of its carbon monoxide and/or hydrogen impurities, is recovered.
    Type: Grant
    Filed: January 24, 1996
    Date of Patent: December 2, 1997
    Assignee: L'Air Liquide, Societe Anonyme Pour L'Etude et L'Exploitation des Procedes Georges Claude
    Inventor: Daniel Gary
  • Method and regenerator for heating a gas
    Patent number: 5690164
    Abstract: A method is provided for heating a gas in a regenerator with a heat accumulation mass consisting of a loose bulk material arranged in a ring between two coaxial cylindrical grids, a hot collection chamber, surrounded by the inner hot grid, for the hot gases and a cold collection chamber, enclosed between the outer cold grid, on the one hand, and the wall of the regenerator, on the other hand, for the cold gases, wherein the increase in the head loss during the heating phase is at least 5 times as great as the product .rho..g.H, in which H is the height of the regenerator, .rho. is the density of the gas at a temperature of 20.degree. C. and g is the acceleration due to gravity, and the gas flow rate is at least equal to 300 m.sup.3 N/h.m.sup.2 of surface area of the hot grid at standard pressure.
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: November 25, 1997
    Assignee: L'Air Liquide, Societe Anonyme pour L'Etude et L'Exploitation des Procedes Georges Claude
    Inventor: Hans-Georg Fassbinder
  • Process and device for the preparation of a flow which is substantially purified with respect to at least one of the impurities oxygen and carbon monoxide
    Patent number: 5685172
    Abstract: A process and apparatus for preparing a flow which is substantially purified with respect to at least one of the impurities O.sub.2 and CO, according to which:a) a flow to be purified, comprising at least 90 mol % of a compound chosen from nitrogen, helium, neon, argon, krypton, xenon or a mixture of these compounds and at least one of the impurities O.sub.2 and CO, is cooled to a temperature of less than -40.degree. C.;b) the cooled flow is passed through an adsorbent for the adsorption of at least one of the impurities O.sub.2 and CO, the adsorbent comprising at least one porous metal oxide;c) a flow which is substantially purified with respect to at least one of the impurities O.sub.2 and CO is recovered.
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: November 11, 1997
    Assignee: L'Air Liquide, Societe Anonyme Pour L'Etude et L'Exploitation des Procedes Georges Claude
    Inventors: Bernard Darredeau, Daniel Gary, Christiane Muller
  • Process and plant for the production of a gas under pressure by cryogenic distillation
    Patent number: 5685173
    Abstract: In a process for the production of gas under pressure by cryogenic distillation, the gas is produced by vaporizing (or pseudo-vaporizing) a liquid drawn off from a distillation column. In order to supply additional gas under pressure, a flow of a gas coming from an external source is at least partially liquefied, and the liquid thus formed is added to the liquid drawn off from the column before or after an optional pressurization step.
    Type: Grant
    Filed: September 24, 1996
    Date of Patent: November 11, 1997
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Mike De L'Isle, Yves Koeberle
  • Heat exchanger with brazed plates and corresponding process for treating a diphase fluid
    Patent number: 5682945
    Abstract: The heat exchanger is of the type comprising a series of first passages (4) in which a diphase fluid circulates, each of the passages being adjacent to at least one second passage (5) for the circulation of another fluid which is a heating or refrigerating fluid. At least one of the first passages (4) comprises, in at least one region of the length thereof, an increase in the cross section of the passage and means (9, 11) for receiving and discharging one of the two phases of the diphase fluid.
    Type: Grant
    Filed: April 10, 1996
    Date of Patent: November 4, 1997
    Assignee: L'Air Liquide, Societe Anonyme pour L'Etude et L'Exploitation des Procedes Georges Claude
    Inventor: Jean-Yves Lehman
  • Argon production
    Patent number: 5682767
    Abstract: A process and system for producing an argon-enriched stream comprising a multiple column air separation system, a first crude argon column, and a second crude argon column is provided. The improved process involves removing a vapor stream from the upper portion of the first argon column; reducing the pressure of the vapor in a pressure reducing device; and then flowing the reduced pressure vapor to a second argon column which operates at a lower operating pressure relative to the first argon column.
    Type: Grant
    Filed: November 18, 1996
    Date of Patent: November 4, 1997
    Assignees: Air Liquide Process and Construction, L'Air Liquide, Societe Anonyme pour L'Etude et L'Exploitation des Procedes Georges Claude
    Inventors: Francois De Bussy, Jean-Pierre Tranier
  • Device and process for the separation of gas by adsorption
    Patent number: 5679134
    Abstract: A device for the separation of gas by adsorption, of the so-called VSA or MPSA type, comprises, between a utilization line (L) and a source (S) of gaseous mixture to be separated, at least one module (M) comprising in series a reversible rotatable machine (R), typically a Roots, an adsorber (A) and a shut-off valve (V). The rotary machine (R) is alternately actuated, in one direction during a first phase of pressurization and of production and then, in the other direction, during a second phase of depressurization and desorption. Used particularly in the production of small and medium volumes of oxygen in modular installations.
    Type: Grant
    Filed: November 8, 1995
    Date of Patent: October 21, 1997
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Jean-Renaud Brugerolle, Christian Monereau
  • Gas control and dispensing assembly and gas storage device equipped with such an assembly
    Patent number: 5678602
    Abstract: Gas control and dispensing assembly comprising a lower unit (1) which is mounted on a gas tank (4) and houses a regulator (10, 9) and an upper unit (5) which is mounted on the lower unit (1) via a threaded ring (24) and houses an indexed flowmeter valve (14, 43) upstream of a low pressure gas outlet (19). The invention is suitable for transportable gas tanks and vehicle-body integrated gas tanks.
    Type: Grant
    Filed: August 12, 1996
    Date of Patent: October 21, 1997
    Assignee: L'Air Liquide, Societe Anonyme Pour L'Etude et L'Exploitation Des Procedes Georges Claude
    Inventors: Gilles Cannet, Emmanuel Fano, Alain Robin
  • Process for introducing a filling gas into an enclosure and installation for employing same
    Patent number: 5676736
    Abstract: The process for introducing a filling gas into an enclosure initially containing a holding gas includes a step of introducing the filling gas into the enclosure as well as a step of extracting a specific gas initially contained in the filling gas or the holding gas from a mixture collected at the outlet of the enclosure, and possibly a step of recycling this extracted specific gas. Before the step of introducing the filling gas, the enclosure is purged using a purging gas which differs from the fill and holding gases.
    Type: Grant
    Filed: February 20, 1996
    Date of Patent: October 14, 1997
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventor: Didier Crozel
  • Method and system for assessing the operating condition of a pressure regulator in a corrosive gas distribution system
    Patent number: 5677480
    Abstract: A method of detecting a malfunction or failure of a pressure regulator in a corrosive or reactive gas distribution system while in use involves continuously measuring or monitoring the output pressure of the pressure regulator, both in the presence and the absence of gas flow. The onset of a malfunction of the pressure regulator can be predicted when the differential output pressure between flowing and non-flowing gas fluctuates highly and increases gradually. Failure of the pressure regulator or of the total system is detected when the differential output pressure in the presence and absence of flowing gas exceeds some experimentally determined value.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: October 14, 1997
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: A. Nimal Liyanage, Eiichi Ozawa, Kazuo Yokogi, Jean-Marie Friedt
  • Process for the separation of mixtures of oxygen and of nitrogen employing an adsorbent with improved porosity
    Patent number: 5672195
    Abstract: The invention relates to a process for the separation of a mixture of oxygen and nitrogen into each of its constituents, including bringing the mixture to be separated, in an adsorption zone, into contact with a selective adsorbent for nitrogen, the adsorbent being an agglomerated zeolite exhibiting an Si/Al ratio lower than 5, a porosity of between 0.38 and 0.60 and a parameter a.sub.k of at least 0.5 s.sup.-1, the parameter a.sub.k characterizing the kinetics of adsorption of nitrogen on the adsorbent in the adsorption zone in accordance with the Linear Driving Force model, it being understood that when the adsorbent is a zeolite containing lithium its porosity can vary between 0.25 and 0.60.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: September 30, 1997
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventors: Serge Moreau, Christian Barbe