Abstract:
A method of drying a gas making use of the distillation of a liquid desiccant, the method comprising the introduction of a stream of make-up liquid containing water and of an organic solvent miscible with water, the solvent being a more volatile solvent than water under the conditions of the method and forming no azeotropes with water, in an intermediate zone of an elongated vertical contact and fractional distillation zone.
Abstract:
A method of liquefying natural gas, wherein the gas (1) is cooled and separated into a liquid phase (6) and a gaseous phase (8) which is expanded (9) and added to the liquid phase in the column (7), at the head of which the gas enriched with methane (21) is separated and recompressed (27) and carried to the liquefaction (32, 33, 34) whereas the liquid phase from the bottom of column (7) is expanded and rectified in column (14); the head effluent (19) being condensed (20) and conveyed as a reflux (25) to column (7); the pressure in column (7) being higher than that of column (14); the C.sub.3 + hydrocarbons from the bottom (16) being separated and the methane liquefaction (33, 34) being conventional.
Abstract:
A cryogenic process of simultaneous selective desulphurization and gasoline removal of a gaseous mixture consisting mainly of methane and likewise containing H.sub.2 S and hydrocarbons with C.sub.2 and more.Said gaseous mixture (1), after having eventually undergone an operation of removal of benzol (25) and then cooling (2) producing condensates (4), is washed between 0.degree. C. and -45.degree. C. by means of a solvent (5) selective of H.sub.2 S to produce a current of methane (64) having a partial pressure in H.sub.2 S below 65 Pa and a liquid phase (9a) rich in H.sub.2 S and containing at least 80% molar of the hydrocarbons of C.sub.3 and more of the gaseous mixture (1). The liquid phase (9a) is subjected to a demethanization (29, 9) producing a demethanized rich solvent (11) and a gaseous phase rich in methane (10), the solvent (11) then is cooled between -25.degree. and -80.degree. C. sufficiently to produce its dissociation in a lower liquid fraction (38) that contains the H.sub.2 S and, in methane equivalent, less than 5% molar of hydrocarbons and an upper liquid fraction (37) formed of the hydrocarbons of C.sub.3 and more. Said fractions (37, 38)are separated and the fraction (38) undergoes a regeneration (46, 16, 20) to produce a current (24) of acid gas rich in H.sub.2 S and containing the small amount cited above of hydrocarbons and a regenerated solvent (21).
Abstract:
The present invention relates to a process and an apparatus for cryogenic fractionation of gas feeds, the apparatus comprising essentially a contact purifying-refrigerating column associated with a fractionating column, an exchange system, a plurality of ducts with valves connecting the above three elements and two closed end independent refrigerating circuits integrated to the exchange system.
Abstract:
A process of and an apparatus for saving energy in a method of liquefying a natural gas by cooling same with the vapor from a liquid coolant sub-cooled after expansion thereof in the liquid condition, the vapor simultaneously sub-cooling the liquefied coolant, the process consisting in expanding the sub-cooled high-pressure liquid coolant in a hydraulic turbine providing mechanical power possibly for driving a rotary machine.
Abstract:
Method and apparatus for cooling a gaseous mixture wherein a fractional condensation of said mixture is carried out under a high pressure by using at least a first stage and a last stage of fractional condensation, the penultimate and the last condensed fractions are expanded down to a low pressure forming a main refrigerating stream, and at least the first condensed fraction of the cycle mixture is expanded down to an intermediate pressure between said high pressure and said low pressure forming an auxiliary refrigerating stream.