Abstract
Fundamental functions of activated sludge are classified into the three : adsorption, sedimentation and separation function. Usually, water quality takes a bad turn by a fall of sedimentation and separation function rather than an adsorption function. Also the authors describe mainly in this paper about the separation function.
Firstly plant functions took a general view on an estimation space. So it was appointed that operating estimation varied from plant to plant and the estimation differed remarkably from optimum estimation. Secondly the aspect of separation was observed about various concentration. Consequently it was found to exist a critical separation concentration. Using this critical concentration, it was possible to evaluate the activated sludge separation function.
The following conclusions are obtained : (1) a clear distinction must be drawn between a plant and a sludge separation function, and the conventional indices are not fit for the activated sludge separation function, (2) the new separation index is proposed, and also the automatic measuring device of this index has been developed, (3) by applying this method to actual plants, it is confirmed that estimation by the new index is very useful.
