The ultimate BOD of a river just below a sewage outfall is 55.0 mg/L, and the...

The ultimate BOD of a river just below a sewage outfall is 55.0 mg/L, and the DO is at a saturation value of 12.0 mg/L. The deoxygenation rate coefficient kd is 0.30/day, and the reaction rate coefficient kr is 0.90/day. The river is flowing at the speed if 52.0 miles per day. The only source of BOD on this river is this single outfall.
1. Find the critical distance downstream at which DO is a minimum.
2. Find the minimum DO.
3. If a wastewater treatment plant is to be built, what fraction of the BOD would have
  
  to be removed from the sewage to assure a minimum of 5.0 mg/L everywhere
  
  downstream?

Expert Solution

Ally Wells answered 2 years ago

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