According to the settling behavior of a suspension process, Figure generated from Table , can be divided into three main sedimentation or flocculation parts. The first part is between 5 and 10 min, the second part is between 15 and 20 min and the last part is between 25 and 30 min. . At these higher concentrations, the suspended solids come into physical contact with one another and are subject to compaction due to the weight of overlying particles and the settling rate will be much lower than in class C regime.