The Flotation System will include the
following items:
- Flocculation System (For
chemical/effluent mixing, coagulation and flocculation)
- Aeration Zone (for aerating,
mixing and fusing the air bubbles to the flocculation
waste stream)
- Flotation Zone (to ensure
sufficient retention to allow for separation and
flotation of solid material from the waste stream)
- Solids Discharge Scrapers (to
direct the skimmings to the auger discharge)
- Discharge weir and channel
(for final effluent)
Chemical addition starts with coagulation dosing at the discharge of
the FF pumps. As waste enters the flocculation system chemical dosing
occurs, creating a large flocculation which is necessary for flotation.
The flocculation system is fitted with a variable speed flocculator which
secures mixing of waste flow and chemicals.
Next, the effluent enters a baffled aeration section. This aerator is
the heart of the system and its unique design enables the production of
very fine micro bubbles. These bubbles attach themselves to solid
particles and float to the surface of the aeration tank. The effluent
overflows a weir into the flocculation tank where the
floated solids remain on the surface and the clarified effluent is
discharged via a submerged pipe. Floated solids are periodically
removed by a scraping mechanism which moves along the surface of the
liquid and deposits the solids into the discharge auger. This scraper
is controlled by a timer mechanism that can be set to provide the most
suitable scraping frequency. Effluent in the aeration tank is recycled
continuously back to the aeration tank by means of the aerator action
along open pipes.
Solids removed by the scraper mechanism are transferred to an auger which
in turn deposits the solids into a suitable container for disposal.
Settled solids are removed with the action of the bottom scraper along
the floor of the flotation zone. The sludge is transferred to a hopper
on the bottom of the tank.
Treated effluent flows from the flotation zone via pipes to a double
weir chamber. The double weir chamber minimizes the no-flow to maximize
flow level in the flotation zone. This ensures that the top scrapers are
effective at all times if needed. From the weir chamber, the flow will
discharge to the outlet chamber and, from there, to the city sewer.
