In: Civil Engineering
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)