GATE Civil Engineering (CE) 2020 Shift 1 Solved Paper

Surface Overflow Rate (SOR) of a primary settling tank (discrete settling) is 20000 litre/m ${}^2$ per day. Kinematic viscosity of water in the tank is $1.01\times {10}^{-2}\frac{{\mathit{c}\mathit{m}}^2}{\mathit{s}}$. Specific gravity of the settling particles is $2.64$. Acceleration due to gravity is $9.81\frac{\mathit{m}}{{\mathit{s}}^2}$. The minimum diameter (in $\mathit{\mu }\mathit{m}$, round off to one decimal place) of the particles that will be removed with $80\%$ efficiency in the tank, is