Two circular clarifiers operated in parallel service a single stage bio-tower system (plastic media) that receives municipal wastewater at an average flow (Qaverage) of 2000 m³/d, with BOD5 = 200 mg/L. The internal flow recirculation ratio is 2.4. The maximum overflow rate for the clarifiers is 1.8 m³/m²-hr. The design procedures require that the sizing of the clarifiers be based on "PEAK" flow which is twice the average flow (Qpeak = 2 × Qaverage), and media depth in the biotower is 3.0 m. Determine: (a) The overall BOD5 removal. (b) the surface area and the diameter of each clarifier. (k = 0.06 min¹; n = 0.5),

Two circular clarifiers operated in parallel service a single stage bio-tower system (plastic media) that receives municipal wastewater at an average flow (Qaverage) of 2000 m³/d, with BOD5 = 200 mg/L. The internal flow recirculation ratio is 2.4. The maximum overflow rate for the clarifiers is 1.8 m³/m²-hr. The design procedures require that the sizing of the clarifiers be based on "PEAK" flow which is twice the average flow (Qpeak = 2 × Qaverage), and media depth in the biotower is 3.0 m. Determine: (a) The overall BOD5 removal. (b) the surface area and the diameter of each clarifier. (k = 0.06 min¹; n = 0.5),

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 circular secondary clarifier will be used to treat an average daily flow (ADF) of 6,000 m3 /d from a high-purity oxygen activated sludge process with a MLSS concentration of 8,500 mg/L. The RAS flow is 2,500 m3 /d. Key design criteria include an overflow rate of 15 m3 /(d.m2 ) and a solids loading rate of 100 kg/(d.m2 ). Determine the minimum diameter (m) of the clarifier to achieve these criteria.
2. The average wastewater flow from a community of 20,000 is 125 gpcd. The 5 day, 20 deg C BOD is 250 mg/L. The suspended solids content is 300 mg/L. A final plant effluent of 50 mg/L of BOD is to be achieved through the use of two sets of identical settling tanks and trickling filters operating in parallel. The settling tanks are to be designed to a standard of 1000 gpd/^2. The trickling filters are to be 6^ deep and operated at an organic loading of 55 lbm/1000^3 d. There is no recirculalon. (1) What settling tank surface area is required? In ft^2 (2) What settling tank diameter is required? In ft (3) Estimate the BOD removal in the settling tanks? In percent % (4) What is the trickling filter diameter? In ft File Explorer O Expert Q&A | Cheq... (66) These
2. The average wastewater flow from a community of 20,000 is 125 gpcd. The 5 day, 20 deg C BOD is 250 mg/L. The suspended solids content is 300 mg/L. A final plant effluent of 50 mg/L of BOD is to be achieved through the use of two sets of identical settling tanks and trickling filters operating in parallel. The settling tanks are to be designed to a standard of 1000 gpd/^2. The trickling filters are to be 6^ deep and operated at an organic loading of 55 lbm/1000^3 d. There is no recirculalon. (1) What settling tank surface area is required? In ft^2 (2) What settling tank diameter is required? In ft (3) Estimate the BOD removal in the settling tanks? In percent % (4) What is the trickling filter diameter? In ft domeved Ward
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