Sand filter

Sand filtration is a physical method for removal of suspended particles from any fluid including water. These suspended particles can be mud, color or dyes, and particles resulting from corrosion. In response to passage of water through the pores of the substate particles, the water suspended particles are trapped, whereby water almost free from suspended particles is obtained.
Aggregation of particles in the pores of the filter results in more pressure drop, whereby the filter should be washed. The input water flow rate entering the filter is usually 5 M3/Hr and the filter washing rate is 15-60 M3/Hr.
The silica used in these filters has purity 99% and is specifically designed for water treatment process.
For charging the filter, desirably the grains with a coarser granulation should be on the top of the filter, while finer particles should remain in the lower layers. The body of sand filter tanks can be metal or fiberglass-reinforced polyethylene.
The test pressure in metal tanks is 10 bars and in fiberglass tanks is 4 bars.
The body of all tanks is made of metal sheets ST 37 with thicknesses 6 and 8 alongside epoxy inner coating.
The operating pressure is 1.5-2.5.
All tanks undergo hydrostatic test under 10 bar pressure.