A town is required to treat 4.2 m /min of raw water for daily domestic supply. Flocculating particles are to be produced by chemical coagulation. A column analysis indicated that an overflow rate of 0.2 mm/s will produce satisfactory particle removal in a settling basin at a depth of 3.5 m. The required surface area (in m ) for settling is

A town is required to treat 4.2 m /min of raw water for daily domestic

1.	A town is required to treat 4.2 m /min of raw water for daily domestic supply. Flocculating particles are to be produced by chemical coagulation. A column analysis indicated that an overflow rate of 0.2 mm/s will produce satisfactory particle removal in a settling basin at a depth of 3.5 m. The required surface area (in m ) for settling is
A.	210
B.	350
C.	1728
D.	21000
Answer» C. 1728

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