Problem 7-29 The initial ultimate BOD after mixing of the Noir River is 50 mg/L. The DO in the river after the wastewater and river have mixed is at saturation. The river temperature is 10 °C. At 10 °C, the deoxygenation rate constant kd is 0.30 d-¹ and the reaeration rate constant k is 0.30 d-¹. Determine the critical point to and the critical DO.

Problem 7-29 The initial ultimate BOD after mixing of the Noir River is 50 mg/L. The DO in the river after the wastewater and river have mixed is at saturation. The river temperature is 10 °C. At 10 °C, the deoxygenation rate constant kd is 0.30 d-¹ and the reaeration rate constant k is 0.30 d-¹. Determine the critical point to and the critical 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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Fluid Materials

In general terms, anything that flows can be termed as a fluid. In other words, a fluid is any substance that cannot resist shear forces and deforms continuously under the application of external shear forces. Fluid materials differ completely from solid materials such as metals and alloys. For instance, if we consider two infinitesimally small cross-sectional areas of fluid materials and solid materials, and apply shear forces to these elements, both the elements will undergo deformation. Upon releasing the shear force, the element of the solid materials will regain its original orientation, but the element of the fluid materials will keep on deforming continuously under the action of the shear force.

Question

Problem 7-29
The initial ultimate BOD after mixing of the
Noir River is 50 mg/L. The DO in the river
after the wastewater and river have mixed is
at saturation. The river temperature is 10 °C.
At 10 °C, the deoxygenation rate constant ka
is 0.30 d-¹ and the reaeration rate constant k
is 0.30 d-¹. Determine the critical point to and
the critical DO.

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