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Instantaneous filtration performance after a back-wash
AFM® grade 1 Instantaneous filtration performance at a water flow at 20m/hr no floculation down to 2 microns
Sand instantaneous filtration performance at a water flow velocity of 20m/hr 16 x 30 grade (Leighton Buzzard deposit
England) at 20m/hr, no flocculation, down to 5 microns
Taking 5 um particle size, there was a gradual decrease in performance of AFM® which stabilised ou at approx 92% removal
efficiency. Sand experience a rapid drop in performance to 50% efficiency then stablised at approx 55%. At 5 um and a water
flow of 20m/hr, AFM® remove 6 times more effective than sand.
In relation to a waer treatment risk analysis, the results confrm the greater securty afforded by AFM® over sand.