Dissolved air flotation (DAF)

The Dissolved Air Flotation units are used to remove the suspended matter and fats from the wastewater (or from water). These particles, together with dissolved solids (COD or nitrogen compounds), constitute an important source of pollution that can be regulated.

 

Principle of Operation:

After the initial coagulation the wastewater goes to the flotation machine. First, it goes to the flocculation, where it is mixed with chemicals. This fosters the formation of tiny flocculent groups of sludge. Then, through a mixing chamber located in the bottom part of the machine, the wastewater (with partly flocculated particles) passes to the flotation unit, where it is mixed with one-micron-diameter air particles, and taken by them to the surface of the tank. There sludge is collected by mechanical scraper. The effluent goes out of the machine. Collected sludge is transported to the ‘sludge pocket’ and pumped out of the flotation machine.

In some models, the mineral sludge which is heavier than water, settles at the bottom in another part of the tank and is automatically collected by the additional pump.

        

Advantages:

  • Effective and flexible technology for suspended solids and fats removal;
  • Wide range of use - for various industries;
  • Special air-pump in DAF unit eliminates the necessity to use the external saturation installations;
  • Several hundred references from the cosmetic, pharmaceutical, petrochemical, dairy, meat, fruit and vegetable, juice and brewing industries from around the world.

 

 Sample references: