A completely mixed activated sludge process is to be used to treat a flow rate of...

A completely mixed activated sludge process is to be used to treat a flow rate of 2.5 MGD. Design a rectangular activated sludge reactor with a 4:1 ratio of length to width. (design only 1 reactor for all flow). The effluent from the plant must not exceed 15 mg/L of BOD5. Use the following design criteria:

a. BOD5 influent = 250.0 mg/L

b. MLVSS (X) = 3500 mg/L

c. Reactor depth = 11 ft

d. Effluent BOD5 must be less than 20 mg/L

e. Y = 0.6 mg VSS/mg BOD5

f. K = 6 day-1

g. KS = 65 mg/L BOD5

h. Kd = 0.08 day -1

i. MLVSS/MLTSS = 0.75

Determine the following: a. Determine the minimum solids retention time (SRT) in days to meet discharge criteria

b. If the actual solids retention time is 4 days, what would be the volume of the activated sludge basin if the wasting flow rate is 40,000 gpd containing 6,400 mg/L of solids.

c. Using the volume of aeration basin in question (b) determine the dimensions of the basin, if the depth is 11 feet, to the nearest even foot

d. What is the hydraulic retention time (HRT) in hours, in the activated sludge basin?

Expert Solution

Ally Wells answered 9 months ago

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