Sketch a typical Streeter-Phelps oxygen-sag curve and state the limitations of the Streeter-Phelps equation shown below: D=: k,Lo 1+ Det k2 – k " (b) Wastewater discharges through an outfall into a slow moving river that has a mean velocity of 3 cm/s. After initial mixing, the dissolved oxygen concentration in the river is 9.5 mg/L, and the temperature is 20°c. The ultimate BOD of the mixed river water is 30 mg/L, the rate constant for BOD at 20°C is 0.48 d' and the re-aeration constant at the same temperature is 0.72 d. The saturation concentration of oxygen is 10.2 mg/L at 15°C. i. Estimate the critical time, to, and location, X, with reference to dissolved oxygen concentration. ii. Estimate the minimum dissolved oxygen at the critical location, and comment on the ecological implication of the same.

Sketch a typical Streeter-Phelps oxygen-sag curve and state the limitations of the Streeter-Phelps equation shown below: D=: k,Lo 1+ Det k2 – k " (b) Wastewater discharges through an outfall into a slow moving river that has a mean velocity of 3 cm/s. After initial mixing, the dissolved oxygen concentration in the river is 9.5 mg/L, and the temperature is 20°c. The ultimate BOD of the mixed river water is 30 mg/L, the rate constant for BOD at 20°C is 0.48 d' and the re-aeration constant at the same temperature is 0.72 d. The saturation concentration of oxygen is 10.2 mg/L at 15°C. i. Estimate the critical time, to, and location, X, with reference to dissolved oxygen concentration. ii. Estimate the minimum dissolved oxygen at the critical location, and comment on the ecological implication of the same.

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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