What's the detention time in hours for a round clarifier that receives a flow of 7 Million Gallons Day. The clarifier is 10 feet deep with a radius of 15 feet.

Answer 1

Hello Adam!

First, you have to calculate the volume of the clarifier, since it's a round one, we have.

V = π * r²*H ; where r is the radius and L is H is height.

We get V = 7068.6 ft³

1 ft³ = 7.4 gal

Therefore, V = 52,307.5 gal

To calculate the detention time, we have to divide the Volume by the flow.

Flow = 7,000,000 gal/24h = 291666.7 gal/h

V/Flow = 52307.5/291666.7 = 0.18h = 10.76 min