The ultimate BOD of a river at the confluence of the river and a sewage outfall is 50 mg/L and the DO is at the saturation value of 9.0 mg/L after mixing. The deoxygenation (or decay) rate coefficient (Ka) is 0.3 d' and the reaeration rate coefficient (K;) is 0.9 d''. The river is flowing at a velocity of 48 miles/day and the only source of BOD is from the sewage discharge. Find the critical distance downstream (in miles) at which DO is a minimum. b. Find the minimum DO (in mg/L). c. If a wastewater treatment plant is to be built, what fraction of the BOD would have to be removed from the sewage to assure a minimum of 5.0 mg/L everywhere downstream? а.

The ultimate BOD of a river at the confluence of the river and a sewage outfall is 50 mg/L and the DO is at the saturation value of 9.0 mg/L after mixing. The deoxygenation (or decay) rate coefficient (Ka) is 0.3 d' and the reaeration rate coefficient (K;) is 0.9 d''. The river is flowing at a velocity of 48 miles/day and the only source of BOD is from the sewage discharge. Find the critical distance downstream (in miles) at which DO is a minimum. b. Find the minimum DO (in mg/L). c. If a wastewater treatment plant is to be built, what fraction of the BOD would have to be removed from the sewage to assure a minimum of 5.0 mg/L everywhere downstream? а.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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