Design the pre$-$anoxic tank for $90\%$ nitrogen removal for the treatment system with the

following design conditions.

Anoxic mixing energy $=8k\frac{W}{{10}^3}m3$

RAS ratio $=0\mathrm{.}75$

Nitrate concentration in RAS $=6m\frac{g}{L}$

$,$ SDNR $=0\mathrm{.}10gN{O}_3-\frac{N}{g}$ MLVSS$.$d

Temperature $=20C$

$R_o=280k\frac{g}{h}$

Your design should include the following:

Active biomass concentration, $m\frac{g}{L}.$

Amount of nitrate feed to the anoxic tank, $k\frac{g}{d}ay.$

Volume of anoxic tank, m$3$

F$/$M ratio

Amount of nitrate to be reduced, $k\frac{g}{?}$ day

Net $O2$ required considering the oxygen credit by nitrate reduction, $k\frac{g}{h}$

Alkalinity savings as CaCO$3,k\frac{g}{?}$ day

Power required for the mixer, Kw