VERFAHREN UND VORRICHTUNG ZUR BIOLOGISCHEN REINIGUNG VON MIT FUER MIKROORGANISMEN TOXISCH WIRKENDEM ABWASSER UNTER GLEICH- ZEITIGER REINIGUNG BIOLOGISCH ABBAUBARER, NICHT TOXISCHER ABWASSER

摘要

The liq. is supplied to a first activated sludge stage together with excess activated sludge stage together with excess activated sludge arising from a second stage in which a liq. contg. impurities which can be decomposed biologically by the activated sludge process, is purified. Pref. the quality of activated sludge supplied to the first stage from the second is regulated as a function of the proportion of retarding and toxic materials in the liq. of the first activated sludge stage. This permits liqs. heavily polluted with materials which retard the action of or are toxic to the micro-organisms of the activated sludge, to be satisfactorily purified without requiring the addn. of other liqs. as diluents.