Consider a primary sedimentation tank (PST) in a water treatment plant with Surface Overflow Rate (SOR) of 40 m /m /d. The diameter of the spherical particle which will have 90 percent theoretical removal efficiency in this tank is ________ mm. Assume that settling velocity of the particles in water is described by stokes s Law. Given: Density of water = 1000 kg/m ; density of particle = 2650 kg/m ; g = 9.81 m/s ; Kinematic viscosity of water (v) = 1.10 10 6m /s

Consider a primary sedimentation tank (PST) in a water treatment plant

1.	Consider a primary sedimentation tank (PST) in a water treatment plant with Surface Overflow Rate (SOR) of 40 m /m /d. The diameter of the spherical particle which will have 90 percent theoretical removal efficiency in this tank is ________ mm. Assume that settling velocity of the particles in water is described by stokes s Law. Given: Density of water = 1000 kg/m ; density of particle = 2650 kg/m ; g = 9.81 m/s ; Kinematic viscosity of water (v) = 1.10 10 6m /s
A.	20.58 m
B.	21.58 m
C.	23.58 m
D.	22.58 m
Answer» E.

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