DAF Technology

 Dissolved Air Floatation (DAF Technology) is widely used clarification process especially in India. DAF technology removes particles from water using air bubbles that collide and fasten to particles. The bubble particles are then separated once they rise to the surface of the tank.

It has applications in several fields which include beverage, municipal, and industrial wastewater, in place treatment of lakes for algae and seawaters for algae and oil spills. DAF technology is easy and energy saving technology.

How does a DAF Technology system work?

Wastewater is pumped into a DAF (Dissolved air flotation) system and mixed with a stream of “whitewater”, which is recirculated clarified water from the DAF that's super saturated with dissolved air. As these two stream mix together, microscopic bubbles attach to solid particulates, giving them enough buoyancy to travel to the surface of the DAF tank.

As solids accumulate during a floating layer of sludge on the highest of the DAF tank, a skimmer gently pushes the sludge toward a discharge tank or hopper.

All solids which don’t float will sink to the “V” bottom of the DAF tank. All settled solids are concentrated and discharged by an automatically controlled pneumatic drain valve.

The purified water flows out via an under-over weir on other side of the DAF unit. A number of this water is employed within the recirculation loop while the remainder flows out of the vessel for discharge or further treatment.

Typically, with the utilization of chemical coagulation prior the DAF, up to 95% reduction of TSS, BOD, FOG are often achieved or up to 75% reductions without chemicals. DAF technology is are often used a primary step before biological wastewater treatment because it are going to be remove an honest portion of the nutrient load and thus reduce the dimensions of the biological treatment system, along side providing a good quality of effluent.

 

Advantages of DAF Technology-

1)      Dissolved Air Floatation is more systematic in removing low-density floc then sedimentation processes.

2)      Dissolved Air Floatation is simpler than sedimentation in removing pathogens like Giardia cysts and Cryptosporidium oocysts.

3)      Dissolved Air Floatation produces floating sludge with higher percent of solids which possibly reduces sludge treatment and disposal.

4)      Energy savings is higher in DAF technology compared to sedimentation plants as smaller motors are wont to run the flocculator, longer filter runs, and fewer filter backwashing of filters.

5)      Smaller footprint and more rapid implementation.