Question 3: BOD demand for denitrification

Calculate how much influent, with a BOD concentration of 180 mg/l, would be needed to bypass the aerobic tank in order to denitrify 40 mg/l of NO₃-N in the anoxic tank. Firstly consider Case A: ignore N incorporated into biosynthesis and secondly consider case B: including a biological yield of 0.4 kg VSS/kg BOD in the balance. Also calculate what the ammonium concentration in the effluent would be in both cases.