A CMAS treatment system must be designed for a municipal wastewater and the following operating conditions: • Effluent flow of 0.39 m³/s leaving the primary clarifier • Effluent soluble BOD5 of 310 mg/L leaving the primary clarifier 20 mg/L of soluble BOD5 allowed in the effluent from the secondary clarifier Negligible suspended solids in the effluent from the secondary clarifier Volatile suspended solids concentration of 4300 mg/L in the aeration tank In the laboratory under log-growth conditions, the microorganisms used in the aeration tank can convert 100 g soluble BOD5 into 55 g Vss Microorganisms in the CMAS system have a death rate constant of 0.05 d. Sludge age in the CMAS treatment system will be 4 days (a) Determine the % treatment efficiency for soluble BOD5 required in the CMAS system. (b) Determine the required volume of the aeration tank (in m²) and HRT (in h). (c) Determine the food-to-microorganism ratio (in d') and the specific substrate utilization ratio (in d'). (d) Determine the expected rate of sludoe production (in kgld).

A CMAS treatment system must be designed for a municipal wastewater and the following operating conditions: • Effluent flow of 0.39 m³/s leaving the primary clarifier • Effluent soluble BOD5 of 310 mg/L leaving the primary clarifier 20 mg/L of soluble BOD5 allowed in the effluent from the secondary clarifier Negligible suspended solids in the effluent from the secondary clarifier Volatile suspended solids concentration of 4300 mg/L in the aeration tank In the laboratory under log-growth conditions, the microorganisms used in the aeration tank can convert 100 g soluble BOD5 into 55 g Vss Microorganisms in the CMAS system have a death rate constant of 0.05 d. Sludge age in the CMAS treatment system will be 4 days (a) Determine the % treatment efficiency for soluble BOD5 required in the CMAS system. (b) Determine the required volume of the aeration tank (in m²) and HRT (in h). (c) Determine the food-to-microorganism ratio (in d') and the specific substrate utilization ratio (in d'). (d) Determine the expected rate of sludoe production (in kgld).

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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