A city wishes to discharge wastewater primary effluent to a river which supports a trout. The state requires the city to show that the trout population is protected. Trout require a minimum of 4 mg/l of dissolved oxygen to survive. Determine the minimum downstream dissolved oxygen concentration from the following information about the wastewater discharge and river. Does the minimum dissolved oxygen concentration meet the requirements? Wastewater discharge=0.45m3/s, river flow rate= 8.5 m3/s, river cross-sectional area=19m2, dissolved Oxygen concentration in the wastewater= 0.2mg/l, dissolved oxygen content of the river upstream = 8.1mg/l, saturation dissolved oxygen concentration at 20 C= 9.0 mg/l, BOD concentration in wastewater = 85 mg/l, BOD concentration upstream in the river= 0.2 mg/l, BOD decay constant = 0.2 d-1, and the reaeration constant for the river= 0.4 d-1.

A city wishes to discharge wastewater primary effluent to a river which supports a trout. The state requires the city to show that the trout population is protected. Trout require a minimum of 4 mg/l of dissolved oxygen to survive. Determine the minimum downstream dissolved oxygen concentration from the following information about the wastewater discharge and river. Does the minimum dissolved oxygen concentration meet the requirements? Wastewater discharge=0.45m3/s, river flow rate= 8.5 m3/s, river cross-sectional area=19m2, dissolved Oxygen concentration in the wastewater= 0.2mg/l, dissolved oxygen content of the river upstream = 8.1mg/l, saturation dissolved oxygen concentration at 20 C= 9.0 mg/l, BOD concentration in wastewater = 85 mg/l, BOD concentration upstream in the river= 0.2 mg/l, BOD decay constant = 0.2 d-1, and the reaeration constant for the river= 0.4 d-1.

Sustainable Energy

2nd Edition

ISBN:9781337551663

Author:DUNLAP, Richard A.

Publisher:DUNLAP, Richard A.

Chapter14: Ocean Thermal Energy Conversion And Ocean Salinity Gradient Energy

Section: Chapter Questions

Problem 14P

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