A settling tank in a water treatment plant is designed for a surface overflow rate of 30(m /day.m ) . Assume specific gravity of sediment particles = 2.65, density of water ( ) = 1000 kg/m , dynamic viscosity of water (m) = 0.001 N.s/m , and Stokes law is valid. The approximate minimum size of particles that would be completely removed is

A settling tank in a water treatment plant is designed for a surface o

1.	A settling tank in a water treatment plant is designed for a surface overflow rate of 30(m /day.m ) . Assume specific gravity of sediment particles = 2.65, density of water ( ) = 1000 kg/m , dynamic viscosity of water (m) = 0.001 N.s/m , and Stokes law is valid. The approximate minimum size of particles that would be completely removed is
A.	0.01 mm
B.	0.02 mm
C.	0.03 mm
D.	0.04 mm
Answer» C. 0.03 mm

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