Dissolved Air Flotation (DAF) Systems

The Dissolved Air Flotation (DAF) systems manufactured by Johnson Screens are designed for the removal of suspended solids, oil and grease, heavy metals, BOD, COD and VOCs. Whether it be laundry, textile, food processing or any other industrial process, Johnson Screens can customize a solution to optimize efficiency.

The Air Dissolving System: Johnson Screens uses a unique air dissolving system that manufacturers the maximum amount of dissolved air "white water," maintaining a very small micron bubble size. The air dissolving recirculation loop is skid mounted compactly under the DAF unit. A special air dissolving pump creates maximum shearing of air bubbles at very high pressure, which eliminates the need for large air dissolving tanks typical of most DAFs.

Coagulation and Flocculation Zone:  The Johnson Screens DAF design utilizes static mixing in a pipe flocculator to achieve coagulation and flocculation. This design eliminates the need for mixing tanks and mixers, which reduces moving parts and maintenance. Each flocculator is custom built to meet the customer's needs.

Dissolved Air Injection:  Dissolved air "white water" is injected to many points along the pipe flocculator. This method allows for the white water to be present during the initial coagulation and flocculation and produces higher efficiencies in a smaller design.

Dissolved Air Blanket:  Not only are the volumes of white water injected into the pipe flocculator, but Johnson Screens also distributes a blanket of white water underneath the sludge blanket. This features ensures flotation of any lazy floc as well as further polishes treated water as it flows to the discharge weir.

Adjustable Discharge Weir:  An adjustable discharge weir provides water level control within the unit to give maximum percent solids in the sludge blanket and discharge sludge. Construction Materials Available in both stainless steel and polypropylene construction, quality materials give longevity and durability to each system.

Automation and Controls:  Johnson Screens offers a variety of system controls, from fully automated PLC touch screen controls and automated flow controls to hand operated control and manual flow controls.

For more information on Johnson Screens Dissolved Air Flotation systems, please contact us.