The completely mixed activated-sludge plant is to treat 10000 m³/day of industrial wastewater. The wastewater has BOD5 of 1300mg/1 that must be reduced to 300mg/1 to discharge to a municipal sewer. The secondary clarifier is designed with underflow of 10000mg/1. Pilot-plant analysis indicates that a mean cell-residence time of 5day, MLSS concentration is 5000 mg/1, Y=0.7kg/kg. Kd=0.03d-¹ Determine: 1)treatment efficiency? 2) The volumetric loading? 3) The volume of the reactor?

The completely mixed activated-sludge plant is to treat 10000 m³/day of industrial wastewater. The wastewater has BOD5 of 1300mg/1 that must be reduced to 300mg/1 to discharge to a municipal sewer. The secondary clarifier is designed with underflow of 10000mg/1. Pilot-plant analysis indicates that a mean cell-residence time of 5day, MLSS concentration is 5000 mg/1, Y=0.7kg/kg. Kd=0.03d-¹ Determine: 1)treatment efficiency? 2) The volumetric loading? 3) The volume of the reactor?

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 aeration time is nearly?
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?
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