Process of treating contaminated soils

US5223147A · kind A · utility

Assignee

• Metallgesellschaft AG · DE

Inventors

• Friedrich Rosenstock · Frankfurt am Main, DE
• Jochen Güntner · Alzenau, DE
• Elmar Haite · Frankfurt am Main, DE
• Horst Dittmann · Büdingen, DE

Key dates

• Filing date: Dec 6, 1991
• Grant date: Jun 29, 1993
• Expiry date: Dec 6, 2011

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S210/922
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Contaminated soils are treated in that an aqueous slurry of the soil is separated into a coarse fraction and a fine fraction, the fine fraction is subjected to flotation, the resulting froth is dewatered and then carried away as a pollutant concentrate, and the underflow from the flotation is dewatered and is then carried away as purified soil. An emulsified oily vegetable oil is used as a collector agent for the selective flotation or an emulsified light mineral oil is used as a collector agent for the selective flotation and a light mineral oil is stirred as a conditioning agent into the fine fraction before it is subjected to the selective flotation.