Q:A city of 200,000 people disposes of 1.05 m.s' of treated sewage that still has a BODU of 28.0 mg. L' and 1.8 mg. L of DO into a river. Upstream from the outfall, the river has a flow rate of 7.08 m. s' and velocity of 0.37 m.s'. At this point, the BODU and 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, ka is 0.61 day", and the reaction coefficient, k is 0.76 day". Assume complete mixing and that the velocity in the river is the same upstream and downstream of the outfall. 1- What is the oxygen deficit and the BODU just downstream from the outfall (just after mixing, before any reaction can occur)? 2- What is the D0 16 km downstream? 3- Calculate the critical time and distance. 4- What is the minimum DO?

Q:A city of 200,000 people disposes of 1.05 m.s' of treated sewage that still has a BODU of 28.0 mg. L' and 1.8 mg. L of DO into a river. Upstream from the outfall, the river has a flow rate of 7.08 m. s' and velocity of 0.37 m.s'. At this point, the BODU and 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, ka is 0.61 day", and the reaction coefficient, k is 0.76 day". Assume complete mixing and that the velocity in the river is the same upstream and downstream of the outfall. 1- What is the oxygen deficit and the BODU just downstream from the outfall (just after mixing, before any reaction can occur)? 2- What is the D0 16 km downstream? 3- Calculate the critical time and distance. 4- What is the minimum DO?

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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