Method and apparatus for separating air by cryogenic distillation

US9091478B2 · kind B2 · utility

Assignee

• L'Air Liquide, Societe Anonyme Pour l'Etude et l'Exploitation des Procedes Georges Claude · FR

Inventors

• Frederic Judas · Le Plessis-Robinson, FR
• Herve Le Bihan · Sucy-en-Brie, FR
• Patrick Le Bot · Saint-Mandé, FR

Key dates

• Filing date: Jul 16, 2010
• Grant date: Jul 28, 2015
• Expiry date: Jul 7, 2032

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F25J2245/40
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The invention relates to equipment for separating air by cryogenic distillation, including: a double air separation column; an exchange line (91); a hot air supercharger (CI) and a cold air supercharger (C2); a first turbine (TI) and a second turbine (T2), each of which is coupled to one of the superchargers; means for bringing all the air to a high pressure that is greater than the mean pressure; means for purifying the air at said high pressure; means for dividing the purified air into two fractions and sending one fraction thereof to the hot air supercharger and one fraction to the cold air supercharger after cooling in the exchange line; means for feeding the second air fraction from the cold air supercharger back into the exchange line; means for sending at least one pressurized liquid from one of the columns into the exchange line; a valve (4, 5); means for sending the non-supercharged air, purified at a high pressure, to the exchange line, so as to be cooled therein, and then to the valve; and means for sending the air, expanded in the valve, to be distilled and/or to the atmosphere.