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Filtration performance and grade of filter media
The standard grade of filter media used in most pressure and RGF filter is a sand of 16 x 30 mesh size, AFM® grade 1 is
equivalent to this grade of sand. However, because AFM® does not biofoul this gives the opportunity to use a much finer
grade of media, grade 0 which has a particle size distribution 0.25 to 0.50mm. This is half the size of 16 x 30 sand and grade
1 AFM®.
At a flow velocity of 20m/hr, sand removed 73% of all 5 micron particles. Grade 1 AFM® removed 97% and grade 0 removed
more than >99.9%
Particle size removal performance of AFM at 20m/hr with no coagulation or flocculation
100.0
95.0
90.0
afm grade 0
85.0
afm grade 1
sand
80.0
75.0
70.0
1
3
4
5
10
15
20
25
30
35
40
Size of particles in Microns