Process for purifying waste water, in particular municipal waste water

摘要

A process for purifying waste water, in particular municipal waste water, with the aid of a two-stage activation plant in which the first stage is operated as a high-loading adsorption stage and the second stage is operated as a low-loading activation stage. The treated waste water discharging from the adsorption stage, which is conducted through an intermediate clarification, is introduced directly or via a trickling filter stage into the second stage. The excess sludge from the intermediate clarification and from a secondary clarification downstream of the second stage is fed to sludge processing. In the high-loading adsorption stage, a biocoenosis chiefly composed of prokaryotes is employed. A part-quantity of the excess sludge from the adsorption stage, which is drawn off from the intermediate clarification, is introduced into the second stage. Formation of bulking sludge in the second stage is avoided by this. <IMAGE>