Wastewater plant discharges effluent in river from the center. Characteristics of River and wastewater is given...

Wastewater plant discharges effluent in river from the center. Characteristics of River and wastewater is given in Table below.

Velocity of River V= 10 cm/s,

After intial mix, Dissolved-oxygen concentration C0 = 9.5 mg/L,

Saturation Dissolved-oxygen concentration at 15 C Cs= 11 mg/L,

Deoxgenation rate at 20 C k1,20 = 0.55 per day,

Reoxgenation rate at 20 C k2,200= 0.85 per day

Temperature of River Tr=12 C

BOD load L0=25 mg/L

How long (in days) it takes to reach DO concentration fully saturation level (11 mg/L)

Expert Solution

Ally Wells answered 1 year ago

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