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In: Civil Engineering

Design an aeration tank for activated sludge wastewater treatment designed to meet an effluent standard of...

Design an aeration tank for activated sludge wastewater treatment designed to meet an effluent standard of 10 mg/L BOD5. The flow from the primary effluent is 10 m3/min with a primary effluent BOD5 of 250 mg/L. The design calls for the suspended solids to equal 3500 mg/L for an SRT of 5 days. The decay rate constant is 0.03 day-1 and the yield is 0.75 mg/mg. Determine:

  1. the tank volume required to meet these specifications,
  2. the resulting mass of sludge wasted each day (kg/day), and
  3. the F/M ratio.

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