Q:$7$ Design a continuous flow stir tank $($complete mix$)$ type activated sludge process plant to

treat $20$ MLD domestic waste water. $BO{D}_5$ of settled waste water to the reactor is $200m\frac{g}{L}$ and

is desired of treated effluent $30m\frac{g}{L}.$ Assume that the plant will be operated at following

conditions.

i$)$ Water contains adequate trace nutrients and nitrogen and phosphorus for the growth of

biomass.

ii$)$ Peak flow rate is $2\mathrm{.}5$ times the daily average flow.

iii$)$ Influent biomass concentration $x_0$ to reactor is negligible