A wastewater treatment plant serving a city of 200,000 discharges 1.10 m3/s of treated effluent having...

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A wastewater treatment plant serving a city of 200,000 discharges 1.10 m3/s of treated effluent having an ultimate BOD of 50.0 mg/L into a stream that has a flow of 8.70 m3/s and an ultimate BOD of its own equal to 6.0 mg/L. The deoxygenation constant ka is 0.20/day. The wastewater has a dissolved oxygen concentration of 2.0 mg/L and a discharge rate of 1.10 m3/s. The river that is receiving the waste has a DO equal to 8.3 mg/L and a temperature of 20°C. The reaeration constant is 0.41 1/day. The saturation DO concentration at 20°C is 9.1 mg/L. a) Assuming complete and instantaneous mixing, estimate the ultimate BOD of the river just downstream from the outfallI. b) If the stream has a constant cross-section, so that it flows at a fixed speed equal to 0.30 m/s, estimate the BOD remaining in the stream at a distance 30,000 m downstream. c) Estimate the initial dissolved oxygen deficit of the mixture of wastewater and river water just downstream from the discharge point. d) Find the time and distance downstream at which the oxygen deficit is at a maximum e) Find the minimum value of DO. f) Sketch the oxygen sag curve. A wastewater treatment plant serving a city of 200,000 discharges 1.10 m3/s of treated effluent having an ultimate BOD of 50.0 mg/L into a stream that has a flow of 8.70 m3/s and an ultimate BOD of its own equal to 6.0 mg/L. The deoxygenation constant ka is 0.20/day. The wastewater has a dissolved oxygen concentration of 2.0 mg/L and a discharge rate of 1.10 m3/s. The river that is receiving the waste has a DO equal to 8.3 mg/L and a temperature of 20°C. The reaeration constant is 0.41 1/day. The saturation DO concentration at 20°C is 9.1 mg/L. a) Assuming complete and instantaneous mixing, estimate the ultimate BOD of the river just downstream from the outfallI. b) If the stream has a constant cross-section, so that it flows at a fixed speed equal to 0.30 m/s, estimate the BOD remaining in the stream at a distance 30,000 m downstream. c) Estimate the initial dissolved oxygen deficit of the mixture of wastewater and river water just downstream from the discharge point. d) Find the time and distance downstream at which the oxygen deficit is at a maximum e) Find the minimum value of DO. f) Sketch the oxygen sag curve.

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Given Data iler waktimatu am 870 6mgL k kd kkA 0411day Satur abron DO 91mg e pomgy 2 mgL Uig Btruhrs ... View the full answer