Method for purifying a natural gas stream

US11154812B2 · kind B2 · utility

Assignees

• L'Air Liquide, Societe Anonyme Pour l'Etude et l'Exploitation des Procedes Georges Claude · FR
• Air Liquide Advanced Technologies U.S. LLC · US

Inventors

• Paul Terrien · Newton, US
• Pascal Marty · Bry-sur-Marne, FR
• Yong Ding · Newton, US

Key dates

• Filing date: Jul 23, 2018
• Grant date: Oct 26, 2021
• Expiry date: Jul 23, 2038

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F25J2245/02
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A process for purifying a natural gas feed gas stream including methane and hydrocarbons, including step a): cooling the feed gas stream; step b): introducing the cooled stream into a first phase separator vessel in order to produce a liquid stream and a gas stream; step c): separating the gas stream resulting from step b) in a membrane unit from which a methane-enriched permeate stream and one partially condensed residue stream enriched in hydrocarbons exit; step d): introducing the residue stream resulting from step c) into a second phase separator vessel to produce a liquid stream and a gas stream; step e): introducing at least one portion of the liquid stream resulting from step d) into a JT expansion means; step f): heating at least one portion of the expanded by introduction into the heat exchanger used in step a) counter-current to the feed stream.