A factory with a wastewater flow of 0.011 m/s and a BODS 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 BODS of the stream is 0.6 mg/L. The BOD rate constants kaat 20 °C are 0.115 d' 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 d². 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 BODS 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 BODS of the stream is 0.6 mg/L. The BOD rate constants kaat 20 °C are 0.115 d' 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 d². 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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