A cover letter for the recycling program for a small community to achieve at least 50 per cent diversion from the landfill.

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You are an engineer designing an aeration tank for a wastewater treatment plant receiving municipal waste. The activated sludge system (aeration tank and secondary clarifier) you design needs to remove 85% of the incoming BODs from the primary effluent, giving a final concentration of 30.0 mg BODs/L exiting the system. Your design will maintain a concentration of 2500 mg VSS/L and F/M ratio of 0.5 g BOD/g VSS d in the aeration tank. In an effort to keep the waste activated sludge low in water, only about 0.1% of the primary effluent flow (Q) exits the WAS line. The secondary effluent has a flow rate of 9990 m³/d. What volume (in m³) will the aeration tank need to be? Write out all equations and state any assumptions as needed. Primary effluent: Q. Xo, So Aeration tank V, X, S Secondary Secondary clarifier effluent: Qe, X, S O RAS line: Q, X., S Activated sludge control volume WAS line: Qwx, S

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Chapter 1, Problem 1.5P

To determine

A cover letter for the recycling program for a small community to achieve at least 50 per cent diversion from the landfill.

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You are an engineer designing an aeration tank for a wastewater treatment plant receiving municipal waste. The activated sludge system (aeration tank and secondary clarifier) you design needs to remove 85% of the incoming BODs from the primary effluent, giving a final concentration of 30.0 mg BODs/L exiting the system. Your design will maintain a concentration of 2500 mg VSS/L and F/M ratio of 0.5 g BOD/g VSS d in the aeration tank. In an effort to keep the waste activated sludge low in water, only about 0.1% of the primary effluent flow (Q) exits the WAS line. The secondary effluent has a flow rate of 9990 m³/d. What volume (in m³) will the aeration tank need to be? Write out all equations and state any assumptions as needed. Primary effluent: Q. Xo, So Aeration tank V, X, S Secondary Secondary clarifier effluent: Qe, X, S O RAS line: Q, X., S Activated sludge control volume WAS line: Qwx, S

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