An activated sludge system using CSTR with sludge recycle has an influent flow rate (Q°) of 2.5 MGD that contains BOD of 200 mg/L. The volume of the aeration tank (CSTR) is 0.6 million gallons. The MLVSS (assume this is X,) in the aeration tank is 2000 mg VSS/L and the decay rate (b) is 0.1/day. The effluent from the secondary clarifier meets NPDES standards for suspended solids and BOD. The concentration of the settled sludge exiting the bottom of the secondary clarifier is 15,000 mg VSS/L. The sludge waste flow rate (Q") is 1 % of the influent flow rate, and the effluent flow rate (Q®) is ~99% of the influent flow rate. a) What is the hydraulic retention time, 0 (d)? b) What is the solids retention time, 0x (d)? Activated sludge with recycle c) What is the F/Ma ratio?

An activated sludge system using CSTR with sludge recycle has an influent flow rate (Q°) of 2.5 MGD that contains BOD of 200 mg/L. The volume of the aeration tank (CSTR) is 0.6 million gallons. The MLVSS (assume this is X,) in the aeration tank is 2000 mg VSS/L and the decay rate (b) is 0.1/day. The effluent from the secondary clarifier meets NPDES standards for suspended solids and BOD. The concentration of the settled sludge exiting the bottom of the secondary clarifier is 15,000 mg VSS/L. The sludge waste flow rate (Q") is 1 % of the influent flow rate, and the effluent flow rate (Q®) is ~99% of the influent flow rate. a) What is the hydraulic retention time, 0 (d)? b) What is the solids retention time, 0x (d)? Activated sludge with recycle c) What is the F/Ma ratio?

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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