A MODEL FOR BATCH SETTLING CURVE

A model is developed for describing sludge blanket interface settling in a batch reactor. The sludge settling curve is considered as one ent ity, not as a conglomerate of several separate parts, and thus describ ed in one model. The model interprets sludge settling as a time-depend ent phenomenon and it describes the settling process from the beginnin g to the end. Since the whole settling curve is modelled, sludge settl eability is accurately assessed. Two parameters of the model can be ea sily estimated with a non-linear estimation method. The derivative of the model can be used for computing sludge blanket interface settling velocity. The agreement between the observed and the computed activate d sludge settling curves shows that the proposed approach is justified .