Water recycling in a melamine production process

US9206140B2 · kind B2 · utility

Assignee

• Casale SA · CH

Inventors

• Arne Schadt · Bad Nauheim, DE
• Robert Schlesinger · Linz, AT
• Gregor Demel · Linz, AT
• Christoph Neumüller · Ansfelden, AT
• Franz Hintermüller · Eisenlohrsweg, AT

Key dates

• Filing date: Oct 8, 2010
• Grant date: Dec 8, 2015
• Expiry date: Oct 8, 2030

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D251/62
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a method for recycling water in a melamine production process comprising—a wet process comprising the steps of aqueous treatment of a melamine melt from a melamine synthesis plant with an aqueous alkali containing solution and crystallization for producing solid melamine and a triazine containing alkaline mother liquor,—a wastewater treatment process comprising the steps of thermal treatment of said triazine containing alkaline motor liquor, and—a recycling process, whereby at least parts of the thermally treated alkaline mother liquor are being recycled to the wet process.