A factory with a wastewater flow of 0.011 m³/s and a BOD; of 590 mg/L discharges into a smallstream. The stream has a minimum dry season flow of 1.7 m/s. Upstream of the factory, theBOD; of the stream is 0.6 mg/L. The BOD rate constants ka at 20 °C are 0.115 di for the factorywastewater and 3.7 di for the stream. The temperature of both the stream and the factorywastewater is 20 °C. After mixing, the D0 was 6.3 mg/L, the velocity was 0.1 m/s, the mean depthwas 2.5 m and the decay constant, ka , was 0.75 d.a. Calculate the initial ultimate BOD after mixing (HINT: First find Lo in each flow]b. Determine the time when the critical DO occur:c. Where does the critical DO occur?'d. Determine whether any fish migration will occur if they require a DO level of at least 3mg/L in their habitat.

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A factory with a wastewater flow of 0.011 m/s and a BOD; of 590 mg/L discharges into a small stream. The stream has a minimum dry season flow of 1.7 m/s. Upstream of the factory, the BOD; of the stream is 0.6 mg/L. The BOD rate constants kat 20 °C are 0.115 di for the factory wastewater and 3.7 di for the stream. The temperature of both the stream and the factory wastewater is 20 °C. After mixing, the DO was 6.3 mg/L, the velocity was 0.1 m/s, the mean depth was 2.5 m and the decay constant, ka, was 0.75 d. a. Calculate the initial ultimate BOD after mixing [HINT: First find Lo in each flow]

A factory with a wastewater flow of 0.011 m/s and a BOD; of 590 mg/L discharges into a small stream. The stream has a minimum dry season flow of 1.7 m/s. Upstream of the factory, the BOD; of the stream is 0.6 mg/L. The BOD rate constants kat 20 °C are 0.115 di for the factory wastewater and 3.7 di for the stream. The temperature of both the stream and the factory wastewater is 20 °C. After mixing, the DO was 6.3 mg/L, the velocity was 0.1 m/s, the mean depth was 2.5 m and the decay constant, ka, was 0.75 d. a. Calculate the initial ultimate BOD after mixing [HINT: First find Lo in each flow]

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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