HYDROBIOLOGICAL INDICATORS OF ACTIVATED SLUDGE OF INDUSTRIAL WASTEWATER TREATMENT PLANT

Abstract

The hydrochemical and hydrobiological indicators of activated sludge of industrial wastewater treatment plant of nitrogen-fertilizers enterprise were characterized. Nitrified activated sludge consists of loose flocs with a large number of filaments (156–495 ind./cm3), which determines its low sedimentation properties (sludge index 260–367 cm3/g). Its microfauna is characterized by low species diversity, with the dominance of the shell amoebae Euglypha. Denitrification sludge is formed from flakes 0.27–0.76 mm2 in size with a large number of dispersed bacteria due to the absence of microfauna under anaerobic conditions. In aeration tanks, intensive aeration and low concentration of wastewater ensure the development of flocculeforming bacteria Zoogloea ramigera, stalked ciliates and rotifers. The activated sludge of aeration tanks consists of compact large floccules 0.64–1.28 mm2 in size with an optimal amount of filamentous bacteria (1009–10 083 ind/cm3).