- Modern flotation clarifiers produce 6 gallons per minute of clarified water per square foot of surface area (6 GPM/SQ FT = 240 L/min M2). Sedimentation clarifiers only produce 0.2 - 1.0 GPM/SQ FT, (10-20 L/min M2). Flotation clarifies approximately 10 times more water with the same surface area than sedimentation.
- Dissolved Air Flotation clarifiers operate with only 16 inches of depth (0.4 M), with a retention time of 2-3 minutes. Sedimentation requires a depth of approximately 80 inches (2.0 M), and a retention time of 60-100 minutes. Flotation operates with 1/4 the depth and 20 times faster than sedimentation.
- Flotation requires a clarifier with a volume of 1.67 gallons to clarify 1.0 GPM (1.0 M3/min.).
Sedimentation requires a clarifier with a volume of 75 gallons to clarify water at the same rate (1 GPM). The volume of sedimentation clarifiers is 45 times larger than flotation clarifiers.
- Initial construction cost is reduced by 30 - 50%. Compact clarifiers are less costly to build than large conventional settling tanks. Enclosing the system in a building and the use of corrosion resistant materials offer odor control and lower maintenance. Land use is substantially reduced.
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