GATE Civil Engineering (CE) 2021 Shift 1 Solved Paper

A secondary clarifier handles a total flow of 9600 m3/d from the aeration tank of a conventional activated - sludge treatment system. The concentration of solids in the flow from the aeration tank is 3000 mg/L. The clarifier is required to thicken the solids to 12000 mg/L, and hence it is to be designed for a solid flux of $3.2\frac{\mathit{k}\mathit{g}}{{\mathit{m}}^2.\mathit{h}}$. The surface area of the designed clarifier for thickening (in m2, in integer) is _____.