51
Recommended Backwash Flow Rates for Various Media
*50
o
F (10
o
C) water temperature, 50% bed expansion
Table 13 Recommended Backwash Flow Rates for Various Media
Media
Tank Diameter
14 in
(35.6 cm)
Tank
16 in
(40.6 cm)
Tank
18 in
(45.7 cm)
Tank
21 in
(53.3 cm)
Tank
24 in
(61.0 cm)
Tank
30 in
(76.2 cm)
Tank
36 in
(91.4 cm)
Tank
Drain Line Flow Control in GPM
*Softening Resin
(5.0 gpm/ft
2
)
(12.25 m/h/cm
2
)
5
7
9
12
15
25
35
*Fine Mesh
Softening Resin
(2.8 gpm/ft
2
)
(6.86 m/h/cm
2
)
3
4
5
7
9
14
20
Multi Layer
(15 gpm/ft
2
)
(36.75 m/h/cm
2
)
15
20
25
36
50
70
105
Birm, Greensand,
Carbon
(10 gpm/ft
2
)
(24.5 m/h/cm
2
)
10
15
17
25
30
50
70
