In: Civil Engineering
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)