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In: Civil Engineering

A wastewater plant with the activated sludge process received 5 × 106 L/day of wastewater with...

  1. A wastewater plant with the activated sludge process received 5 × 106 L/day of wastewater with a BOD5 of 500 mg/L. The primary clarifier removes 30% of the BOD and primary clarify effluent has no biomass (Xi=0 mg/L). Recycle (Qr) and waste sludge (Qw) flows are 25% and 2% of Qin, respectively. Effluent BOD5 from secondary clarifier and waste sludge is 20 mg/L. Microorganism concentration in the waste sludge (Xw) is 6,000 mg/L. Soluble BOD5 is biologically converted into CO2 and Y (yield coefficient) is 0.5 mgVSS /mgBOD
    1. Calculate the value of X and the volume of the tank

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