KOMBINASI DISSOLVED AIR FLOTATION DENGAN ULTRAFILTRASI PADA PEMISAHAN AIR BERLUMUT

Green water is water with dissolved algae. Dissolved algae in water can be a nuisance. In this research, dissolved air flotation followed by ultrafiltration was used to separate algae from green water. DAF as a pretreatment before ultrafiltration can prolong membrane’s lifetime and improve its removal performances in the green water treatment process. Chemical agent (coagulant) that used for coagulation in this research is alum and PAC, Pressure used in this operation is 5-7 Bar.Coagulation feed’s turbidity os 40 – 60 NTU. Obtained the result that the proper coagulant using daf for green water is PAC. For PAC, the optimum concentration is 25 gr/L, while alum is 50gr/l. . This research also proved that the DAF pretreatment before ultrafiltration in green water treatment can helped out the works of ultrafiltration membrane