STIRRING AND AERATION SYSTEM FOR THE UPGRADING OF SMALL WASTE-WATER TREATMENT PLANTS

A novel agitating system has been developed which allows for individua l or combined operation of stirring and aeration processes. Basic flui d mechanical considerations led to the innovative hyperboloid design o f the stirrer body, which ensures high efficiencies in the stirring an d the aeration mode, gentle circulation with low shear forces, excelle nt controllability, and a wide range of applications. This paper prese nts the basic considerations which led to the operating principle, the technical realization of the system and experimental results in a lar ge-scale plant. The characteristics of the system and the differences to other stirring and aeration systems are illustrated. Details of the technical realization are shown, which conform to the specific demand s of applications in the biological treatment of waste water. Special regard is given to applications in the upgrading of small compact wast e water treatment plants.