A water treatment plant is to process 30,000 m3/d of raw water. A tapered flocculation basin having four flocculators with velocity gradients 40/sec, 30/sec, 20/sec and 10/sec is to be designed with cross-flow paddle units. The basin may be a maximum of 10 m wide and 4 m deep to join to the settling basin. The optimum Gt value for this system was found to be 3.5 × 104 at 20 °C. Suppose that every compartment is square in shape. Verify:

(i) Basin dimensions

(ii) Draw the plan and cross sections of the flocculator with dimensions

(iii) Power needs in each compartment