Verfahren zur Verbesserung der Faserstoffrueckgewinnung in Waessern der Papier-, Pappen- und Zellstoffindustrie

摘要

The recovery by flotation of fibrous materials from waste waters obtained in the paper, card-board and cellulose industry is improved by adding to the waste water a condensation product of urea and a 1,2-alkylenimine, carrying a substitutable hydrogen atom at the nitrogen atom, or an oligomer thereof. A preferred condensation product is that obtained from equimolar amounts of urea and ethylenimine.