An Effective Method to Remove Suspended Solids & FOG (Fats, Oil & Grease)

Flotation is an effective wastewater treatment process designed to treat for total suspended solids (TSS), BOD (Biological/Chemical Oxygen Demand), and Fats, Oils, & Grease (FOG).

This robust physical-chemical wastewater treatment solution is utilized by many industrial clients as a key component of their wastewater treatment facility. 

Dissolved air flotation (DAF) consists of separating solids from the water phase by  attaching the solids to fine air bubbles to decrease the density of the particles which float instead of sinking.  The rising solids are called the “float” and are skimmed off the surface and further processed in the sludge train.

Improving Separation with Coagulation & Flocculation


To further enhance performance in the DAF unit, chemicals can be added to increase separation. Two common types of chemicals used in the DAF process are coagulants and polymer flocculants. Coagulant additives, such as ferric chloride or aluminum sulfate, are positively charged and neutralize the negatively charged particles in the wastewater and create microflocs. Related to coagulation, flocculation is the addition of polymers to encourage microflocs to join together and more easily attach to the dissolved air within the tank and float to the top of the unit to be skimmed-off.

Typical Applications for Dissolved Air Flotation (DAF)

  • Fats, Oils, & Grease (FOB) Removal
  • Wastewater Pre-treatment
  • Wastewater  Tertiary Treatment (P removal)
  • Sludge Thickening
  • Anaerobic/Aerobic Post Treatment and Sludge Separation
  • Filter Back Wash treatment
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High-Performance DAF Technology to remove FOG (Fats, Oil, & Grease) and Suspended Solids
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