An activated sludge treatment system to treat a wastewater flow rate of 0.3 m/s of primary effluent. The mixed liquor suspended solids concentration is 2100 mg/l, while the substrate concentration in the primary effluent is 300 mg/l. If the food to microorganism ratio of the process is 0.50 mg BOD/mg vss.day and the removal efficiency of the system 90%. The volume of the aeration tank in cubic meter is: a. 500.6 b. 1200.3 c. None

An activated sludge treatment system to treat a wastewater flow rate of 0.3 m/s of primary effluent. The mixed liquor suspended solids concentration is 2100 mg/l, while the substrate concentration in the primary effluent is 300 mg/l. If the food to microorganism ratio of the process is 0.50 mg BOD/mg vss.day and the removal efficiency of the system 90%. The volume of the aeration tank in cubic meter is: a. 500.6 b. 1200.3 c. None

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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The 550-bed Atlanta Hospital has a small, activated sludge plant to treat wastewater from the hospital. The average daily hospital discharge is 1.50 m3 per day per bed, and the average soluble BOD5 after primary settling is 450 mg/L. The aeration tank effective liguid dimensions of 10 m x 10 m x 5 m. The plant operating parameters are as follows: MLVSS - 2,600 mg/L; MLSS - 1.20 (MLVSS); Settling sludge volume after 30 min. = 200 mL/L. The F/M ratio is nearly?
8 Determine the solid loading rate on a secondary circular clarifier (diameter = 20 m) if the plant influent load is 2 ML/d. The recycle flow from secondary clarifier to the activated sludge system (aeration basin) is set to 10% of the influent load. It is also known that the aeration basin produces an MLSS (mixed liquor suspended solids) concentration of 3000 mg/L.
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The aeration tank for a completely mixed aeration process is being sized for a designwastewater flow of 4500 m3/d. The influent COD is 150 mg/L. The design effluent COD is7 mg/L. Recommended design parameters are a sludge age of 10 days and MLVSS of 1400 mg/L. The expected Sludge Volume Index is 100 ml/g. The selection of these values takes into account the anticipated variations in wastewater flows and strengths. The kinetic constants from a bench-scale treatability study are Y = 0.60 mg VSS/mg COD and ke = 0.06 per day. Calculate:a. the hydraulic residence time and volume of the aeration tankb. the food/microorganism ratioc. the sludge production rated. the sludge recycle ratioe. the oxygen requirement
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