(pictured from left)
flotation system uses a unique pump which creates micro bubbles.
Units are designed based on the air-solids ratio. Seventy-five
percent of the activity has been in food and beverage but
activity is increasing in the municipal sector. A unit started
up on a wastewater plant in Hawaii a year ago is achieving low
BOD and TSS.
This system can
achieve removal efficiencies and effluent qualities far superior
to traditional DAF systems. Dissolved Air Flotation (DAF) is the
process whereby micro-air-bubbles cause suspended materials to
float to the surface of a vessel to achieve liquid/solids
separation. In the WWW/RESOURCE DAF, the wastewater first enters
the low shear mixing pipe flocculator where coagulants and
flocculants may be introduced to increase the particle size
along with "whitewater." Whitewater is a mixture of a portion of
the DAF effluent, which has been saturated with atmospheric air
via the Nikuni air dissolving technology. The wastewater then
enters the vessel across the length of the system. The velocity
of the water is significantly reduced to maximize separation
potential. Inside the vessel, the microbubbles, which have
attached to the particle surface affect the particle density,
cause the suspended solids to float to the surface where a chain
and flight skim them from the surface into a top cone. Heavy
sand and grit particles settle into the cone bottoms, where a
timer function controls the removal. The "clean" liquid is
continuously removed at several points inside the vessel and
passes over pipe weirs into an effluent box. From the effluent
box, the wastewater gravity feeds out of the system.
polypropylene constructed DAF system is the first in kind and
provides tremendous treatment flexibility. Its wide range of pH
tolerance allows treatment of wastewater at ranges where
impurities can be removed more efficiently and cost effectively.
Polypropylene Characteristics to learn more about the
benefits of this material.