Dissolved Air Floatation (DAF), is a physio-chemical system which separates suspended solids in wastewater. DAF units are a more cost-effective alternative to conventional sedimentation clarification processes.

DAF units are excellent for: removing fine suspended solids, cleaning up water, recycling and discharging to the city sewer system.

Feed water is often dosed with a coagulant (usually alum or ferric salts) and/or flocculant (usually polyaluminum chloride, PACl). The role of the coagulant is to destabilize particles in the raw water and remove inorganic and organic materials present in the wastewater, while the flocculant is used to combine the destabilized materials and form flocs to be removed from the wastewater.

Post coagulation/flocculation, the wastewater is passed on to the floatation tank where micro bubbles (20-50 micron size) will attach to the waste flocs causing them to float to the surface of the water to be skimmed. The micro bubbles are formed as a result of part of the clarified water leaving the DAF unit being recycled and passed through an air dissolving tube (air drum). The water is pressurized and saturated with a small

amount of compressed air. As the water is released back into the floatation tank, it comes into contact with atmospheric pressure causing the bubbles to be released.

Clarification rates of 97% or higher can be achieved using dissolved air floatation systems.

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PROTEC is a privately owned company established in Doha, Qatar engaged in the fields of Engineering, Supply, Construction, Installation, Commissioning, Operation and Maintenance of various types of equipment for the Water, Waste Water, Energy, and Industrial markets.


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