{"id":2237,"date":"2026-08-24T15:17:58","date_gmt":"2026-08-24T08:17:58","guid":{"rendered":"https:\/\/hydromasterindonesia.com\/?p=2237"},"modified":"2026-09-02T15:24:27","modified_gmt":"2026-09-02T08:24:27","slug":"dissolved-air-flotation-daf-cara-kerja-dan-aplikasinya","status":"publish","type":"post","link":"https:\/\/hydromasterindonesia.com\/en\/dissolved-air-flotation-daf-cara-kerja-dan-aplikasinya\/","title":{"rendered":"Dissolved Air Flotation (DAF): How It Works and Its Applications"},"content":{"rendered":"

Industrial wastewater is not always filled with heavy, settleable solids. Often, pollutants consist primarily of lighter particles such as oils, greases, and fine Total Suspended Solids (TSS) that remain suspended in the water column. To address these specific wastewater characteristics, dissolved air flotation (DAF) technology serves as the most effective solution.<\/p>\n

Unlike clarifier systems that rely on gravitational settling, DAF utilizes engineered microscopic air bubbles to force light pollutants to rise rapidly to the water's surface.<\/p>\n

In terms of performance, DAF can achieve over 95% removal of oils and greases, up to 90% TSS removal, and a significant reduction in BOD and COD levels in a single process step.<\/span><\/p>\n

How a Dissolved Air Flotation<\/a> System Works<\/b><\/h2>\n

The flotation of impurities is achieved through a precise sequence of hydraulic pressurization and air injection steps:<\/span><\/p>\n

    \n
  1. Coagulation and Flocculation<\/b><\/li>\n<\/ol>\n

    Raw wastewater is first mixed with coagulant and flocculant chemicals in an initial tank to bind micro-impurities into larger clumps (flocs).<\/p>\n

      \n
    1. Pressurized Air Injection<\/b><\/li>\n<\/ol>\n

      A portion of clarified effluent is pumped back into a specialized saturator vessel. In this high-pressure tank, air is dissolved into the water until fully saturated.<\/span><\/p>\n

        \n
      1. Micro-Bubble Release<\/b><\/li>\n<\/ol>\n

        The air-saturated water stream is suddenly released into the main flotation tank. The sudden pressure drop instantaneously generates millions of microscopic air bubbles.<\/span><\/p>\n

          \n
        1. Flotation Process<\/b><\/li>\n<\/ol>\n

          These micro-bubbles attach firmly to the flocs, raising them rapidly to the surface to form a thick foam layer (sludge blanket).<\/p>\n

            \n
          1. Skimming<\/b><\/li>\n<\/ol>\n

            Sistem pengeruk mekanis (<\/span>skimmer<\/span><\/i>A mechanical skimmer continuously sweeps the floated sludge layer into a discharge trough, leaving clarified water at the bottom of the tank.<\/span><\/p>\n

            Key Components of a DAF System<\/b><\/h2>\n

            A complete DAF system consists of several key integrated components:<\/span><\/p>\n\n\n\n\n\n\n\n\n\n
            Component<\/b><\/td>\nDefinition<\/b><\/td>\n<\/tr>\n
            Flotation Tank<\/span><\/td>\nThe primary vessel where separation occurs. Engineered with specific geometry to ensure even bubble distribution and optimal laminar flow.<\/span><\/td>\n<\/tr>\n
            Pressure Tank and Saturator<\/span><\/td>\nA pressurized vessel where air is dissolved into recycled effluent under high pressure.<\/span><\/td>\n<\/tr>\n
            Pressure release valve (PRV)<\/span><\/td>\nA pressure drop control valve that generates micro-bubbles as water enters the flotation tank.<\/span><\/td>\n<\/tr>\n
            Mechanical Skimmer<\/span><\/td>\nA surface-mounted scraper mechanism that continuously skims and discharges floated sludge.<\/span><\/td>\n<\/tr>\n
            Recycle pump<\/span><\/td>\nA pump that recirculates a portion of treated effluent back through the air saturation system to maintain a consistent micro-bubble supply.<\/span><\/td>\n<\/tr>\n
            Chemical Dosing System<\/span><\/td>\nA dosing unit installed upstream of the flotation tank to feed coagulants and flocculants for enhanced separation efficiency.<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            What Is the Difference Between DAF and SAF?<\/b><\/h2>\n

            In industrial wastewater treatment, you may also encounter the term SAF (Suspended Air Flotation). While both systems serve to float light pollutants, they differ fundamentally in how they generate air bubbles.<\/p>\n

            In a DAF system, air is dissolved into water under high hydraulic pressure, so when the pressure is released, the bubbles generated are extremely microscopic and uniform.\u00a0<\/span><\/p>\n

            Conversely, an SAF system generates bubbles mechanically (using vortex generators or specialized pumps) without dissolving air under high pressure.\u00a0<\/span><\/p>\n

            As a result, bubbles in SAF systems tend to be larger, making them well-suited for coarse waste but less optimal for lifting fine particles compared to DAF technology.<\/span><\/p>\n

            Applications of DAF Across Industrial Sectors<\/b><\/h2>\n

            Due to its high pollutant removal efficiency, dissolved air flotation serves as a critical pre-treatment technology across various manufacturing sectors:<\/span><\/p>\n