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A wastewater treatment plant with activated-sludge process treats wastewater for 120,000 m3/d. The effluent standard for...

A wastewater treatment plant with activated-sludge process treats wastewater for 120,000 m3/d. The effluent standard for both BOD and TSS is 20 mg/L. Influent TSS concentration is 450 mg/L and influent BOD concentration is 220 mg/L. MLSS concentration is 3500 mg/L (Assume no nitrification and temperature is 20°C). Determine: (20 pts) (a) Influent BOD and TSS concentration to the aeration tank if the treatment efficiencies in primary clarifier are 30% and 70% for BOD and TSS, respectively. (b) Determine sludge production as kg TSS/d (c) What is the design volume and retention time of the aeration basin (m3)? (d) Determine the F/M ratio in units of kg BOD5/kg MLVSS-day.
(According to your design you can assume some parameters i.e SRT but do not forget to check both your assumptions and your results are in the desirable design conditions)

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