english Dissolved Air Flotation (DAF) for Oily Wastewater Treatment
Flotation water treatment, particularly Dissolved Air Flotation (DAF), is highly effective for oily wastewater treatment. It efficiently removes free oil, emulsified oil, and suspended solids by introducing fine air bubbles that attach to oil droplets, causing them to float to the surface for skimming.
Key Advantages for Oily Wastewater
- High Removal Efficiency (90-99%) for free oil and grease.
- Breaks Oil-Water Emulsions when combined with coagulants (e.g., aluminum sulfate, polyaluminum chloride).
- Handles Variable Loads – suitable for industrial effluents from petrochemical, food processing, and metalworking industries.
- Compact & Fast – requires less space and shorter retention time than sedimentation.
Limitations
- Less Effective for Soluble Oils (may require additional chemical or biological treatment).
- Chemical Dependency – coagulants and pH adjustment are often needed.
- Foam Management – excessive oil can cause foam, requiring proper skimming control.
Best Applications
- Oil refineries, machining coolants, and food processing wastewater.
- Pretreatment before biological or membrane filtration.
- For highly emulsified oils, combining DAF with electrocoagulation or membrane filtration improves results.
