Dissolved Air Flotation Clarifier

Dissolved air flotation (DAF) clarifiers remove suspended solids from water as cost-effective alternative to conventional sedimentation clarification processes. The advantages of DAF clarifiers are their ability to treat a wide range of suspended solids in water at a high rate of solids removal and for wastewater sludge thickening. Millions of micron sized air bubbles in the DAF thickener float solids to the tank surface, forming a concentrated sludge blanket.   A scoop removes the thickened sludge.


DAF clarifiers are excellent for removing fine suspended solids and for cleaning up water clarity problems. DAF clarified water is excellent for recycling, or for discharging to the city sewer system.

If coagulating and flocculating chemicals are added to the influent, they need mixing and retention time. Extreme ups and downs in water temperature and pH can also impact performance of a DAF clarifier. With an oily waste in the wastewater an oil-water separator may be needed ahead of the DAF EQ tank. Pipe sizing needs to be engineered correctly. Optimum DAF performance and chemical cost savings will be achieved when all necessary DAF auxiliary equipment is engineered and field piped properly. FARAN well designed DAF treatment system will lead to lower capital costs and a small plant foot print.

Dissolved Air Flotation technology may be utilized cost effectively for the following applications:

Phosphorus removal; paper fiber recovery; chemical; pharmaceutical; refineries; breweries; dairies; oil and gas; agricultures run off; food; bakeries; poultry; fish processing; meat processing and meat packing; rendering plants; slaughter houses; potato processing; vegetable oil processing; canning water; soap industry; starch removal; laundries; textile effluent; ballast water; car wash operation; heavy metal removal; sludge thickening; membrane system pre-treatment; primary clarification; secondary clarification; water recycling; turbidity color; algae bloom control; and

FARAN’s DAF prefabricated package will be included but are not limited to:

Contact Chamber and Flotation Tank: The influent wastewater shall enter the DAF unit through a flanged influent header into the contact chamber. Simultaneously, the recycle (whitewater) stream shall be mixed with the influent wastewater

Micro Bubble Generator: Wastewater influent enters the DAF clarifier flotation tank mixed with fine micron bubbles. To attain a high solids removal rate, it is important to have excellent and abundant fine micron bubbles all equal in size and to have minimized all water turbulence in the DAF clarifier tank. A key factor for maximizing the efficiencies of the DAF clarifier is the generation of all equally sized micro bubbles with no coarse air bubbles. Equal size fine bubbles, 20 to 50 micron size will give the suspended solids an equal and steady rise rate of 10 to 12 inches per minute to the tank surface.

Float Removal System: The unit shall be equipped with a chain and flight skimmers to remove top floats, driven by gear reducer with motor assembly. The float material shall be removed in a co-current direction. This design involves moving the float bed on the surface down the length of the unit to a separate compartment in the direction of flow and allows for longer float residence time prior to removal, resulting in drier float material.

Settled Solids Removal System: Full-length sloped side walls channel shall concentrate settable material to a trough in the bottom of the tank for removal.

Control Panel: The controls will be housed for controlling system according to project requirement and environmental condition such as outdoor placement or explosion proof require otherwise. The control panel will include the ability to automatically send out alarms to the required personnel such as maintenance.  It can also have the ability to send out reports to the required personnel such as production or management.

Paint and Coatings: All motors, pumps, drives, instruments, control panels, and valves will be shipped with the FARAN's standard coatings.