- A The Sieve Analysis Results For A Stratified Sand Media To Be Used In A Rapid Sand Filter With A Depth Of 1 2 M Are 1 (81.02 KiB) Viewed 19 times
(a) The sieve analysis results for a stratified sand media to be used in a rapid sand filter, with a depth of 1.2 m, are summarized in the following table. Percentage (by weight) of sand retained 2.0 5.0 12.0 25.0 24.0 15.0 13.0 3.0 1.0 Mean size of sand (mm) 0.96 0.85 0.75 0.67 0.58 0.51 0.42 0.35 0.25 m Another alternative arrangement using non-stratified sand media with a diameter of 0.8 mm and a depth of 1.5 m is also proposed by the consultant. You are asked to compare the two alternative designs and make a recommendation for the rapid sand filter with appropriate justification(s). The following conditions are applicable: Water temperature = 10°C Porosity of sand =0.4 (stratified bed) Porosity of sand = 0.6 (non-stratified bed) Filtration constant (stratified bed) = 6 Filtration constant (non-stratified bed) = 5 Sphericity of sand = 0.9 Specific gravity of sand = 2.65 Kinematic viscosity of water at 10°C = 1.312x10 mº/s Density of water at 10 C = 999.7 kg/m? Filtration rate = 6 m/h