A city of 20,000 people disposes of 1.05 m3/s of treated sewage that still has an ultimate BOD of 28.0 mg/L and 1.8 mg/L DO into a river. Upstream from the outfall, the river has a flow rate of 7.08 m3/s and a velocity of 0.37 m/s. At this point, the ultimate BOD and the DO in the river are 3.6 and 7.6 mg/L, respectively. The saturation value of DO (at the temperature of the river) is 8.5 mg/L. The deoxygenation coefficient is 0.61/day, and the reaeration coefficient is 0.76/day. Assume complete mixing and the velocity in the river is the same upstream and downstream of the outfall. What is the oxygen deficit and the ultimate BOD just downstream from the outfall (just after mixing, before any reaction can occur)?

A city of 20,000 people disposes of 1.05 m3/s of treated sewage that still has an ultimate BOD of 28.0 mg/L and 1.8 mg/L DO into a river. Upstream from the outfall, the river has a flow rate of 7.08 m3/s and a velocity of 0.37 m/s. At this point, the ultimate BOD and the DO in the river are 3.6 and 7.6 mg/L, respectively. The saturation value of DO (at the temperature of the river) is 8.5 mg/L. The deoxygenation coefficient is 0.61/day, and the reaeration coefficient is 0.76/day. Assume complete mixing and the velocity in the river is the same upstream and downstream of the outfall. What is the oxygen deficit and the ultimate BOD just downstream from the outfall (just after mixing, before any reaction can occur)?

Solid Waste Engineering

3rd Edition

ISBN:9781305635203

Author:Worrell, William A.

Publisher:Worrell, William A.

Chapter8: Landfills

Section: Chapter Questions

Problem 8.5P

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