Question

( Water & Westwater Treatment Curse )

b) Design of a Sand Filter A 1) Design a new sand filter for a small operation. The est rate for this site is 1880 m/day. The surface overflow ra exceed 145 m3/m2/d. What will be the surface area of the f can use some leftover Ottawa sand (dzo - 0.00055m) from your filtration project. How deep should the filter be? (C3) (5) te shod You 2) The filter unit can remove 70%ofturbidity from the source water The effluent co Calculate the initial concentration of the turbid water? What steps are required to achieve 90%removal fromthis filterunit (2+3) (C) ncentration of the turbidity is found to be 0.5 NTU.

Answer 1

Design o sand filter g = 1880 m^3 /day S O R = 145 m^3/ m^2 /d SOR = Q/surface Area (B times L) therefore 145 = 1880/surface Area therefore surface Area = 12 97 m^2 path insufficient to find depth of filter filter unit can remove 70 % of insanity from source water efficient concentration = 0 5 N/v = 0 3 times x = 0 5 x = 1 67 N/u concentration of initial forbid water rightarrow By increasing the length of filter we can increase the efficiency of filter I e 90 % rightarrow By increasing the length less particle will be escaped from the to filter & more particles will be arrested we can also increase the efficiency of water filter unit to N 90 % by changing the filter media