Apparatus for the liquefaction of natural gas and methods related to same

US6581409B2 · kind B2 · utility

Assignee

• Bechtel BWXT Idaho, LLC · US

Inventors

• Bruce M. Wilding · Idaho Falls, US
• Dennis N. Bingham · Idaho Falls, US
• Michael G. McKellar · Idaho Falls, US
• Terry D. Turner · Ammon, US
• Kevin T. Raterman · Idaho Falls, US
• Gary L. Palmer · Bellevue, US
• Kerry M. Klingler · Idaho Falls, US
• John J. Vranicar · Concord, US

Key dates

• Filing date: Feb 27, 2002
• Grant date: Jun 24, 2003
• Expiry date: Feb 27, 2022

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S62/929
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

An apparatus and method for producing liquefied natural gas. A liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream passes through a turbo expander creating work output. A compressor is driven by the work output and compresses the process stream. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is divided into first and second portions with the first portion being expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. The second portion of the cooled, compressed process stream is also expanded and used to cool the compressed process stream. Additional features and techniques may be integrated with the liquefaction process including a water clean-up cycle and a carbon dioxide (CO2) clean-up cycle.