A completely mixed activated sludge plant treats wastewater at a rate of 2,565 m³/d. The influent BOD is 280 mg/L, and the MLVSS in the aeration tank is 2,500 mg/L. The F/M ratio for the aeration tank is 0.35 kg BOD/kg MLVSS.d. Assuming 30% of BOD is removed in the primary tank, determine the organic loading rate in kg BOD/m³.d and the volume of the aeration tank in m³.

A completely mixed activated sludge plant treats wastewater at a rate of 2,565 m³/d. The influent BOD is 280 mg/L, and the MLVSS in the aeration tank is 2,500 mg/L. The F/M ratio for the aeration tank is 0.35 kg BOD/kg MLVSS.d. Assuming 30% of BOD is removed in the primary tank, determine the organic loading rate in kg BOD/m³.d and the volume of the aeration tank in m³.

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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A completely mixed activated sludge process is being designed for a wastewater flow of 3 MGD using kinetic equations. The influent BOD of 180 mg/L is essentially all soluble and the design effluent soluble BOD is 10 mg/L. The mean cell residence time is selected to be 8.0 days for sizing the aeration volume tank, and the MLVSS is 2500 mg/L. The kinetic constants from a bench-scale treatability study are Y = 0.60 Ib VSS/Ib BOD and Kd = 0.06 day-1. ---Determine the efficiency of soluble BOD removal. For this, you will have to recognize substrate concentration in the coming flow (So) and the concentration of substrate in the exiting flow (Se).
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