Breaking down aromatic compounds in industrial wastewaters

US6258281A · kind A · utility

Assignee

• BASF SE

Inventors

• Edmund Niedbalski · Baton Rouge, US
• Laurance R. Thurman · Baton Rouge, US
• Irene Troetsch-Schaller · Bissersheim, DE
• Ludwig Schuster · Schifferstadt, DE
• Dieter Voges
• Peter Zehner · Ludwigshafen, DE
• Klaus Bittins · Bischofswerda, DE
• Rudolf Schnur

Key dates

• Filing date: Jun 21, 1999
• Grant date: Jul 10, 2001
• Expiry date: Jun 21, 2019

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S210/909
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

A process for breaking down aromatics in industrial wastewaters that contain small amounts of aromatics by reaction with an ozone-containing oxygen stream at a temperature of from 40 to 70.degree. C. and at a pH of from 4 to 7, involves treating industrial wastewaters that contain small amounts of aromatics in two stages with an oxygen stream that contains from 5 to 8% by volume of ozone with thorough mixing by causing the wastewater to flow upward through two reaction zones, the overflow of the wastewater at the top of the first reaction zone entering the second reaction zone at the base, the purified wastewater being obtained at the top of the second reaction zone, the ozone-containing oxygen stream first entering at the base of the second reaction zone, and the waste gas obtained at the top of the second reactor being introduced at the base of the first reaction zone, and, furthermore, a gas containing less than 0.2% by volume of ozone being obtained at the top of the first reaction zone.