Q. A water treatment plant treats 6000 m3 of water per day. As a part of the treatment process, discrete particles are required to be settled in a clarifier. A column test indicates that an overflow rate of 1.5 m per hour would produce the desired removal of particles through settling in the clarifier having a depth of 3.0 m. The volume of the required clarifier, (in m3, round off to 1 decimal place) would be
Solution:
Flow rate = 6000 m3 / d a y
Over flow rate = 1.5 m/hour = 1.5 × 24 m / d a y = 36 m / d a y
Flow area = Flow rate/over flow rate
= 6000/36
= 166.67 m 2 Volume required for clarifier
= flow area × depth
= 166.67 × 3
= 500 m 3