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A Cascade aerator is used in a groundwater treatment plant to reduce the concentration of methane...

A Cascade aerator is used in a groundwater treatment plant to reduce the concentration of methane (CH4) and in the same time to increase the oxygen concentration. The height of each step of the cascade is 0.40 m. The design temperature is 10 0C. The following data is given:

Item

CH4

O2

CW,0

1.50 mg/L

0.70 mg/L

Cg

2 ppb

210000 ppm

kd

0.043

0.039

k (efficiency per step)

27%

25%

Calculate the saturation concentration of CH4 and O2 in water under 1 atmospheric pressure.

What is the required number of cascade steps (n) needed to achieve 91.94% removal of CH4 from water? What is the concentration of CH4 in water in mg/L after aeration in this cascade?

What is the concentration of oxygen in water in mg/L after aeration in this cascade?

What is the length of the Cascade aerator if its capacity is 15 m3/h per 1 m length of the step? The total water flow to be treated is 990 m3/h.

What is the total surface area of the cascade if the width to height ratio of the steps is 1:1?

Expert Solution

Amanda K answered 4 months ago

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