Abstract: A process for the high-yield recovery of ethylene and heavier hydrocarbons from the gas produced by pyrolysis of hydrocarbons in which the liquid products resulting from the fractionated condensation of a cracking gas for the recovery of almost all the ethylene, are supplied to a distillation column, called a de-ethanizer, at different intermediate levels. At the top of the de-ethanizer the vapor of the column distillate is treated directly in an acetylene hydrogenation reactor, the effluent containing virtually no acetylene being separated by a distillation column called a de-methanizer, into an ethylene- and ethane-enriched tail product, while the head product is recycled by compression or treated for subsequent recovery of ethylene.

Abstract: A process and apparatus for separation of a gas mixture. A process and an installation for cryogenic separation of the constituents of a natural gas under pressure in a first phase separator in which the constituents of each phase are separated in a distillation column. Part of the gaseous fraction from the top of the column is recycled into the highest stage of the column. The process also includes branching of part of a first top fraction from the first phase separator. The process also includes separation of a first bottom fraction from the first separator, in a second separator.

Abstract: Process for the high-yield recovery of ethylene and heavier hydrocarbons from the gas produced by pyrolysis of hydrocarbons (1) in which the liquid products (12-15, 23) resulting from the fractionated condensation of the cracking gas (1) for the recovery of almost all the ethylene, are supplied to a distillation column (C1), called the de-ethanizer, at different intermediate levels, at the top of which the vapor (31) of the column distillate is treated directly in an acetylene hydrogenation reactor (R1), the effluent containing virtually no acetylene being separated by a distillation column (C2) called the de-methanizer, into an ethylene- and ethane-enriched tail product (43), while the head product (44) is recycled by compression or treated for subsequent recovery of ethylene.

Abstract: Process and installation for separation of a gas mixture, and gases obtained by this installation. The present invention pertains to a process and an installation for cryogenic separation of the constituents of a natural gas under pressure (14) by a first phase separator (B1) in which the constituents of each phase are separated in a distillation column (C1). Part of the gaseous fraction (5) from the top of the column (C1) is recycled into the highest stage of the column. The process also includes branching (9) of part of a first top fraction (3) from the first phase separator. The process also includes separation of a first bottom fraction (4) from the first separator, in a second separator (B2). Other modes of embodiment are also described.