Method for producing ammonia on the basis of a nitrogen-hydrogen mixture from natural gas

US7470415B2 · kind B2 · utility

Assignees

• Lurgi GmbH · DE
• Ammonia Casale SA · CH

Inventors

• William Davey · Frankfurt am Main, DE
• Ermanno Filippi · Castagnola, CH

Key dates

• Filing date: Oct 24, 2001
• Grant date: Dec 30, 2008
• Expiry date: Dec 13, 2021

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/52
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A method for producing ammonia from natural gas, fed to an autothermic reformer with an O2 rich gas. Crude synthesis gas is produced at temperatures of 900 to 1200° C., pressures of 40 to 100 bar and in the presence of a cracking catalyst. The crude synthesis gas is led through a catalytic conversion system to convert CO to H2, thereby obtaining a conversion synthesis gas with a H2 content of at least 55 vol.-% and a CO content of not more than 8 vol.-%. The conversion synthesis gas is subjected to a gas purification to remove CO2, CO and CH4, thereby producing an N2—H2 mixture that is subjected to a catalytic ammonia synthesis. The ammonia produced can at least be partially converted to urea by reacting it with CO2.