Question

(Grade III) In an attempt to correct a filamentous growth in an activated sludge process, you want to inject chlorine into the RAS flow stream at the dosage of 2.5 pounds of chlorineper1000 pounds of return activated sludge suspended solids. Show the calculations to find the proper chlorinator tor feed setting (in pounds of chlorine per day), given the following information: Average Plant Flow Rate = 9,0 MGD MLSS Conc. = 2,850 mg/L. RASFlow Rate = 3.3 MGD MLVSS Conc. = 2,600 mg/L WAS Flow Rate to DAF = 1.2 MGD RÁS Conc. = 8,500 mg/L.

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