Clack Filter Ag, 1 Cubic Foot Box
Clack Filter-Ag has many outstanding advantages over the more common granular filter media used for suspended solids reduction. Its fractured edges and irregular surface provides a high surface area and complex flow path for efficient removal of suspended solids down to the 20-40 micron range. The larger particle size creates less pressure loss through the filter and allows deeper sediment penetration into the bed for higher loading and longer filter runs.
This large and irregular shape prevents the screening and caking of sediment in the top several inches of the filter bed as happens in the typical sand filter, thus preventing a rapid build up of had loss and blinding problems. Filter-Ag's light weight means lower backwash rates and better bed expansion to release trapped sediment and rinse the filter media during a backwash cycle. This ideal combination of particle shape, size and density make it a good choice where quality water filtration and water conservation are important.
Although not intended to be an iron reduction media, extensive field experience has shown Filter-Ag's rough and jagged surface to be very good at entrapping the fragile iron flock that forms after dissolved iron has been oxidized. The fragmented edges are apparently good flock collection points for the precipitated iron. Typical oxidation methods include aeration, ozonation and chlorination.
Advantages:
- There is less pressure loss through a bed of Filter-Ag than through most other filter medias
- Light weight requires lower back-wash rates then those required for other filter medias
- High service rates result in lower equipment costs and a savings in space
- High sediment reduction capacity results in longer filter runs, with a substantial savings in backwash water and time out of service
- Reduced shipping cost due to light weight/cu. ft.
- Replacement of sand with Filter-Ag in existing installations may increase filter capacity 100% or more. Caution should be taken upon start-up that the lightweight Filter-Ag is not washed to drain
Physical Properties:
- Color.......................................Light grey to near white
- Bulk Density...........................24-26 lbs/cu. ft.
- Specific Gravity......................2.25 gm/cc
- Mesh Size...............................12 x 30
- Effective Size..........................0.67 mm
- Uniform Coefficient................1.8
- Hardness.................................6 (Mohs scale)
Conditions for Operation
- Water pH Range.....................wide range
- Max Water Temperature.........104°F/60°C
- Bed Depth...............................24-36 in.
- Freeboard................................50% of bed depth (min.)
- Service Flow Rate...................5 gpm/sw. ft. although considerably higher rates are often used
-Backwash flow rate..................8-10 gpm/sq. ft.
- Backwash Bed Expansion.......20-40% of bed depth
Upon installation allow bed to soak overnight before backwashing
