Flocculation Tank Design Parameters

Two parallel tanks (see plant layout)

Two staged taper floc

G₁ = 40 s^-1

G₂ = 15 s^-1

Paddle Design (see Figure 2)

4 arms

2 paddles/arm

Distance from shaft to center-line of the inside paddle is 3.0 feet

Distance from shaft to center-line of outside paddle is 5.5 feet

Paddle Length = 12 feet

Paddle Width = 6 inches

Flocculation Tank Dimensions

Width = 20 ft

Length = 26 ft (Each stage is 13ft in length)

Depth = 13 ft

a)What is the rotational speed of the paddles in the second compartment? Assume Cd = 1.6. 

(b)Does the peripheral speed of the outside paddle in the second compartment fall within typical design requirements?