Method for producing urea pellets

US7838080B2 · kind B2 · utility

Assignee

• Glatt Ingenieurtechnik GmbH · DE

Inventors

• Karlheinz Rumpler · Weimar, DE
• Bernhard Wand · Apolda, DE
• Michael Jacob · Munich, DE
• Reinhard Bober · Weimar, DE
• Reinhard Nowak · Binzen, DE

Key dates

• Filing date: Aug 1, 2006
• Grant date: Nov 23, 2010
• Expiry date: Jul 23, 2027

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F01N2610/12
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A method for producing urea pellets having a narrow range of grain sizes and a sphericity >75% and a defined residual moisture ≦0.5% is provided. The method provides urea pellets having the properties required which meet the requirements of the automotive industry for use thereof in reducing emissions from diesel engines. The method includes spraying a urea-containing liquid having a temperature between ambient temperature and above the melting point of the urea into the high particle density region of the spray zone of a near circular gas, material flow of a spouted bed apparatus and onto the particle surface of the material, which is dried and granulated in the gas flow at a temperature of not more than 130° C. at a controlled heat and mass transfer rate while being separated.