Primary effluent is to be treated by two parallel trains of the complete mixed activated sludge...

Primary effluent is to be treated by two parallel trains of the complete mixed activated sludge process. Assume average flow conditions, and the primary sedimentation performance is described in question two above. Assume the following for the activated sludge process: i) plant effluent BOD of 8mg/L ii) biomass yield of 0.55kg biomass/kg BOD iii) endogenous decay rate (kd)= 0.04day-1 iv) Solids retention time= 8days v) MLVSS concentration in the aeration tank of 3000mg/L vi) waste and recycle solids concentration of 12,000mg/L a. Determine the aeration tank volume in cubic meters b. Determine the return cycle (recycle) flow rate in cubic meters per day (and in MGD) c. Determine the food to microorganism ratio (F/M) for the aeration tank in kg BOD per day per kg MLVSS d. Determine the design hydraulic detention time in hours

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Amanda K answered 2 years ago

The primary effluent is to be treated by two parallel trains of the complete mix activated...

The primary effluent is to be treated by two parallel trains of the complete mix activated sludge process. The average daily wastewater design flows of 2.0 MGD and assume that the primary sedimentation process removes 60% of the suspended solids and 40% of the BOD5 of the raw sewage. The following data are given: • Plant effluent BOD5 of 8 mg/L • Biomass yield of 0.55 kg biomass / kg BOD • Endogenous decay rate (kd) = 0.04 day-1 •...

Discuss briefly activated sludge age in terms of treated effluent quality.

An activated sludge system with recycle (CMFR) uses to treat primary effluent after sedimentation.Use the appropriate...

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Design an aeration tank for activated sludge wastewater treatment designed to meet an effluent standard of...

Design an aeration tank for activated sludge wastewater treatment designed to meet an effluent standard of 10 mg/L BOD5. The flow from the primary effluent is 10 m3/min with a primary effluent BOD5 of 250 mg/L. The design calls for the suspended solids to equal 3500 mg/L for an SRT of 5 days. The decay rate constant is 0.03 day-1 and the yield is 0.75 mg/mg. Determine: the tank volume required to meet these specifications, the resulting mass of sludge...

A completely mixed activated sludge process is to be used to treat a flow rate of...

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A wastewater treatment plant with activated-sludge process treats wastewater for 120,000 m3/d. The effluent standard for...

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9. What is the importance of controlling the F/M ratio in suspended mixed activated sludge systems?...

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Two types of flow regime are normally used in the design of an activated sludge process,...

Two types of flow regime are normally used in the design of an activated sludge process, namely completely mixed and plug flow (both are continuous). Using first order kinetic reaction, demonstrate which flow regime provide a better performance, given the followings: Q = 550 m3/d t = 6 hours Co = 225 mg/L k = 0.15 d-1

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