An extended Aeration process is used in a WWTP$.$ The Plant receives $1$ MLD with a BCOD

of $350$mg$/$L$.$ Calculate the following,

a$)$ Effluent COD

b$)$ Required volume, if MLSS within the reactor $=4000$ mg$/$L given MLSS$/$MLVSS $=1\mathrm{.}5.$ Ks$=$

$100$ mg$/$L$.$ Consider, k $=0\mathrm{.}1$ mg$/$L$/$day$,$ kd $=0\mathrm{.}05$ mg$/$L$/$day and YT $=0\mathrm{.}5.$

c$)$ If flow rate doubles and sedimentation tank$$s inefficiency cause a loss of $0\mathrm{.}075\%$ suspended

solids, calculate the steady state effluent COD. Given entire VSS is biomass only.