L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des

Pierre Gauthier

Christian Monereau

Xavier Vigor

Rene Dupont

Corinne Garot

Jean-Claude Villard

Catherine Denis

Jerome Jutard

Steel-making method and plant

A process and installation for the cryogenic purification of impure hydrogen, of the type in which impure hydrogen is cooled under a low pressure PO to a temperature sufficiently low to condense a predetermined proportion of the impurities, by heat exchange in a thermal heat exchange line (3) with purified hydrogen and with a residual fraction containing the expanded preliminarily condensed impurities (in 11, 12) to a low pressure P1. The remaining cold is supplied by the expansion of purified hydrogen in a turbine (8) with gas bearings and the expanded hydrogen is added to the light impurities expanded at the cold end of the heat exchange line. The turbine (8) is supplied with the gas leaving its bearings (17), after cooling of hydrogen at the labyrinthine seal (18) of the turbine is withdrawn under a pressure slightly less than the interstitial pressure Pi which prevails between the rotor (14) and the stator (16) of this turbine.

Process and installation for the cryogenic purification of hydrogen

Process and apparatus for the purification of hydrogen by cryogenic treatment of a gas containing also nitrogen oxides and unsaturated hydrocarbons as two types of constituents which react together in an undesirable fashion when cooling achieves an intermediate temperature higher than the low temperature of the treatment. The process comprises cooling the gas to a first temperature higher than that intermediate temperature; eliminating from the gas one of the two types of constituents at this first temperature; and continuing the cooling of the gas to the low temperature. The elimination of one type of component is effected by washing the gas with a liquid adapted to dissolve it. This liquid contains at least one saturated hydrocarbon and is obtained by a partial condensation of an auxiliary gas which contains at least one of hydrogen and a heavy constituent whose value can be increased. The gas treated can be a residual gas from catalytic cracking in a fluidized bed (FCC), and the auxiliary gas can be a hydrotreatment purge gas.

Process and apparatus for the purification of hydrogen by cryogenic

Process for the purification of a gas containing selectively adsorbable impurities, of the type using several adsorbers with, for each adsorber, a cycle comprising the following operating phases which are offset from one adsorber to the next timewise by a fraction 1/n of the duration of the cycle in which n is the number of adsorbers, the cycle comprising substantially isobaric production at a high pressure of the cycle, this production comprising the admission of impure gas to be treated into an adsorber at a first end of the adsorber with circulation of this gas in the adsorber and simultaneous withdrawal from a second end of the adsorber of purified gas, the direction of flow in the adsorber from the first end to the second end being cocurrent and the opposite direction being countercurrent; regeneration of the adsorber comprising a decompression of the adsorber to a low pressure of the cycle, this decompression comprising at least one stage in which a residual gas is withdrawn countercurrent from the adsorber; and increasing the pressure to the high pressure of the cycle. A portion of the residual gas is mixed with the impure gas to be treated, and the rest of the residual gas is purged.

Process for the purification of a gas by adsorption

A light component of the compressed mixture is separated by permeation. The remaining heavy fraction is condensed with water, sub-cooled and expanded. The light component, cooled at the same temperature, is added to the sub-cooled condensate, and the whole is vaporized under low pressure to produce the required refrigeration.

Refrigerating process and apparatus utilizing a refrigerating mixture

Methanol is catalytically cracked (at 4) then the essential portion of the components other than CO is removed by washing with water (at 5), selective adsorption (at 7) and permeation (at 8). The process and apparatus has application to the production of moderate quantity of carbon monoxide.

Process and apparatus for the production of carbon monoxide

Method and installation for recovering the heaviest hydrocarbons from a

This process is of the type in which there is compressed in at least two stages 2, 6 a mixture of cooling fluids composed of constituents of different volatilities and in which, after the last stage 6 and after at least an intermediate compression stage 2, the mixture is partly condensed, the condensed fractions are expanded and vaporized in heat exchange with the fluid to be cooled before being compressed again. According to the invention, at least one of the condensation stages is carried out by sending to a distillation column 7 the mixture issuing from the corresponding stage of the compressor. This enables the thermodynamic irreversibility to be decreased and consequently permits a reduction of the specific cooling energy.

Process and plant for the cooling of a fluid and in particular the

The starting gas is partly condensed in an exchanger 1. The refrigerating power is supplied, on one hand, by the free expansion of the liquid fraction and, on the other hand, by expansion in a gas-bearing turbine of the vapor fraction rich in hydrogen. A small part of this vapor fraction is used to feed auxiliary gases to the turbine, then is cooled in the exchanger 1, expanded and injected into the expanded liquid fraction so as to obtain a sufficiently low bubble point. The invention is useful in recovering hydrogen from purge gases of apparatus for ammonia synthesis, the purge gases being composed of hydrogen and less volatile components.

Hydrogen-concentrating process and apparatus

Method and apparatus for liquefying a gas such as natural gas, utilizing at least one cycle fluid comprising a refrigerating mixture, with at least one first principal cycle fluid under a low pressure in countercurrent heat exchange with the gas which is to be liquefied and with at least one second principal cycle fluid under a high pressure. At least one secondary cycle fluid is obtained by withdrawing a portion in liquid phase from the refrigerating mixture at the high pressure and is expanded to the low pressure and is then added to the first principal cycle fluid. The heat exchange takes place in at least one heat exchanger comprising a stack of plates which form uninterrupted longitudinal compartments forming passages for the first principal cycle fluid under a low pressure, these compartments extending from the cold end of the exchanger, and a plurality of longitudinal compartments forming passages for at least one of the second principal cycle fluid and the fluid to be liquefied, these latter compartments extending to the cold end of the exchanger. The addition of the secondary fluid to the first principal fluid takes place in a distributed manner into each low pressure compartment in at least one transverse volume extending along the thickness of the exchanger, this volume being located at heat exchange distance from the inlets and outlets of the compartments forming passages for the first principal fluid under low pressure.

Method and apparatus for gas liquefaction

This invention relates to the reheating of a cold cryogenic fluid by heat exchange with a warm liquid, commonly water. The cold cryogenic fluid first flows into a descending tube and then into a rising tube whereas the water trickles along the tubes and from an upper supply, as far as a base manifold. The invention is particularly applicable to the reheating and revaporization of liquified natural gas.

Growing community of inventors

Fresnes, France

Pierre Gauthier