Biological purification of effluent waters

摘要

Process for biological purification of waste waters, esp. urban effluent water, in which water from a mechanical pre-clarifier stage (1), pref. a multichamber clarifier pit, is passed continuously or discontinuously or overflows into a buffer vessel (2), from where it is metered by pump (3) into a biological filter (4) which pref. consists of one or more concentric, wound, perforated drainage tubes lying flat in running water, and microbial C-decomposition of the organic contaminants and N-decomposition of the N-contg. contaminants takes place by nitrification and denitrification, whereby the O2 required by the bacteria naturally present is supplied from the O2 content of the running water by continuous diffusion through the pores of the biofilter, and due to the biofilter an equilibrium of the biologically purified water is achieved, as it flows through the whole length of the biological filter and out into the running water stream.