Data from a field study on a step-aeration activated-sludge secondary are as follows:aeration tank volume =...

Data from a field study on a step-aeration activated-sludge secondary are as follows:aeration tank volume = 120,000 ft3= 0.898 milliongalloninfluent wastewater BOD = 128 mg/Leffluent SS = 26 mg/Leffluent wastewater BOD = 22 mg/Leffluentwastewater flow = 3.67 mgdSS in waste sludge = 11,000 mg/LMLSS in aeration tank = 2350 mg/Lwaste sludge flow = 18,900 gpd = 0.0189 mgd return sludge flow = 1.27 mgd Using these data, calculate BOD loading and MLSS inaeration tank. Also, compute the sludgeage (solids retention time), aeration period, return sludge rate, BOD removal efficiency, and sludge production (in pounds of excess suspended solids per pound of BOD applied).

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Ally Wells answered 4 months ago

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