A Simple Method of Evaluating the Structural Strength and Behavior of Aerobic Granules in the SBR System

摘要

A simple and effective method based on the centrifugation technique was developed and applied to evaluate the structural strength of aerobic granules. The volume compression ratio of aerobic granules used in this study, which ranged from 0.72 to 0.94, was larger than that of sludgeflocs, which ranged from 0.21 to 0.29 at 3000 ×g to 10000 ×g. The critical centrifugal forces applied on the compact structure of aerobic granules and sludge flocs were 7000 ×g and 5000 ×g respectively. The sludge density of the aerobic granules changed from 1.024 g/mlto 1.028 g/ml at 3000 ×g to 10000 ×g, which indicated the stability of their porous structure. Result of analysis of extracellular polymeric substance revealed that their high protein content potentially servers an important function in their formation and structural strength.