In this study, the application of conventional flotation and floc-flotation methods to the wastewater containing suspended particles have been investigated. The experiments were carried out in two stages in the Jameson flotation Cell. The results obtained from the two methods were compared. The effect of flotation time and polymer type on the fine particle removal efficiency and residual turbidity was also determined. As a result of experimental studies, it was found that higher particle removal recovery and lower residual turbidity were obtained by floc-flotation compared to conventional flotation. Increasing flotation time increased fine particle floatability and decreased residual turbidity. In 1st stage of the experiments, 96.6% of the floatability recoveries and 304 NTU residual turbidity value was obtained with the combination of anionic polymer (SPP 508) and anionic surfactant (Aero 845) at the end of the 10 minutes flotation time. After 10 minutes of 2nd stage experiments, over 98% of floatability recoveries were obtained by floc flotation. The residual turbidity value of wastewater was decreased from the initial turbidity value of 12000 NTU to 78 NTU by anionic polymer, to 39 NTU by cationic polymer, and 27 NTU by a nonionic polymer.

Flocculation and flotation methods have been applied individually to achieve the removal of suspended particles from wastewater. However, in this study, the floc-flotation method where these two methods are applied together in a mechanically agitated cell and the use of combinations of different type surfactant and polymer to achieve floatability of fine particles are investigated. The conventional and floc-flotation experiments were carried out to determine the effect of different parameters such as collector type and dosage, pH, flotation time, condition time and polymer/surfactant interactions on floatability of very fine particles. When the results of floc-flotation and conventional flotation were compared, it has been found that higher floatability values were achieved with floc flotation. It can be obtained 96.8% floatability of particles in presence of anionic surfactant (Aero 845, 750 g/t) and nonionic polymer (SPP N 134, 30 g/t) at pH 8 and 5 min. conditioning time for 5 min. flotation time by floc flotation in the mechanical cell.

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