| Title |
A Study on the Concentrations of Residual Aluminum and the Characteristics of floc in Coagulation |
| Authors |
고영송 ; 남상호 ( Young Song Ko ; Sang Ho Nam ) |
| Abstract |
In public water supply systems, Alum and/or PAC has been used as a coagulant. It is well known that in general their use led residual aluminum concentration increased in filtered water. This study was conducted to investigate the optimum conditions that both the concentration of residual aluminum and turbidity are minimized. At the same time, the physical characteristics of floc such as floc strength. floc settling rate, floc size and type were observed. The results obtained at a given experimental condition can be summarized as follows. With the increase of mixing rate, rapid and slow, both the concentrations of residual aluminum and turbidity were increased and the same trend was observed in increment of mixing time. The size of floc produced was smaller in high rapid mixing rate, and the larger floc was more complex in the shape. The mean size of floc produced was 33-63㎛ in diameter. The concentrations of residual aluminum and turbidity were increased with the increment of mechanical floc breakup strength. When the degree of floc breakup was large. the reunion capacity was more deteriorated, by consequent, the flocs showed slow settling rate. |