Process for automatically controlling the detoxification of waste waters containing nitrite ions

US4280914A · kind A · utility

Assignee

• Deutsche Gold- und Silber-Scheideanstalt Vormals Roessler

Inventors

• Helmut Knorre · Seligenstadt, DE
• Joachim Fischer · Rodgau, DE

Key dates

• Filing date: Dec 4, 1979
• Grant date: Jul 28, 1981
• Expiry date: Dec 4, 1999

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S210/903
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

In the detoxification of waste waters containing nitrite ions by means of hydrogen peroxide the addition of hydrogen peroxide is automatically controllable by adding the hydrogen peroxide continuously or in portions with continuous measurement of the pH and stopping the addition when no further reduction of the pH is caused by it. By control of the hydrogen peroxide addition through the change of the pH it is guaranteed that sufficient hydrogen peroxide is added to reach a complete detoxification of the waste water while on the other hand there is not wasted hydrogen peroxide unnecessarily.