The following are average operating data from a secondary activated sludge: Wastewater flow = 29160 m3/d...

The following are average operating data from a secondary activated sludge:

Wastewater flow = 29160 m3/d

Vol. of aeration tanks = 8400 m3

Influent SS = 120 mg/L Influent BOD5 = 170 mg/L

Effluent SS = 22 mg/L Effluent BOD5 = 20 mg/L

Volatile fraction of mixed liquor and effluent suspended solids is 0.65.

Mixed liquor suspended solids = 2500 mg/L

Waste sludge flow = 200 m3/d SS in Waste sludge = 9800 mg/L

Determine the following:

Aeration period, Food to micro-organisms in kg BOD/kg MLVSS /d, Volumetric BOD Loading ,Sludge age ,Observed yield in gVSS/g BOD5 ,True yield in gVSS/g BOD5 assuming a kd of 0.05 d-1 ,Daily oxygen demand

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Ally Wells answered 6 months ago

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