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Home Courses Treatment of Urban Sewage Course materials Lectures 4. Elaboration Question 4

4. Elaboration Question 4

Course subject(s) 4. Activated sludge process

Question 4: Activated sludge process

A conventional activated sludge plant, consisting of an aeration tank and secondary settler receives domestic sewage from a Dutch town “Y” with an average dry weather flow (adwf) of 15,000 m3/d and an average BOD of 250 mg/l. The volume of the aeration tank is 3,500 m3 and the concentration of mixed liquor suspended solids in the aeration tank is 4 g/l.

  • What would be the approximate number of inhabitants in town “Y”? Explain your guess.
  • Calculate the organic sludge loading rate in the activated sludge plant of town “Y”.
  • Would the town “Y” sewage treatment plant be a nitrifying activated sludge plant? Explain.

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