Process for purifying gaseous effluents

US4296081A · kind A · utility

Assignee

• Charbonnages de France · FR

Inventors

• Michel Nomine · Verneuil-en-Halatte, FR
• Gerard Chelu · Verneuil-en-Halatte, FR

Key dates

• Filing date: Feb 1, 1980
• Grant date: Oct 20, 1981
• Expiry date: Feb 1, 2000

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01D53/72
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A process for purifying gaseous effluents containing aldehydes comprises submitting the gaseous effluents to the simultaneous action of SO.sub.2 and NH.sub.3 followed by washing with water. The ratio of the required quantities of NH.sub.3 and SO.sub.2 is between 2:1 and 3:1. When the gas to be purified naturally contains NH.sub.3, as is for instance the case in rendering plants, the quantity of NH.sub.3 to be added to the gas is reduced accordingly. Conversely when the gas to be treated naturally contains SO.sub.2, the quantity of SO.sub.2 to be added to the gas is also reduced accordingly. The most favorable ratio would correspond to a pH of the washing waters of between 7 and 7.5. ;