Two activated sludge aeration tanks at Twickenham Park Estates are operated in series. Each tank has the following dimensions: width 7 m, length 30 m, effective fluid depth 4.3 m. The plant's operating parameters are as follows: (i) (ii) (iii) (iv) (v) Flow = 0.0796 m³/s Soluble BOD, after primary settling = 130 mg/l MLVSS = 1500 mg/l MLSS=2100 mg/1 Settled sludge volume after 30 minutes = 230.0 ml/1 (a) Estimate the aeration period, F/M ratio, SVI, solids concentration in the return sludge. (b) It is desired that the soluble BOD, within the effluent leaving the plant be 8 mg/l. If the insoluble BOD, associated with the final effluent leaving the plant is 30% of the current NEPA TSS standard, what is the maximum BOD, expected in the final effluent stream for this well mixed activated sludge plant? Hint: Which metric discussed in class would best represent the period for which the wastewater is aerated?

Two activated sludge aeration tanks at Twickenham Park Estates are operated in series. Each tank has the following dimensions: width 7 m, length 30 m, effective fluid depth 4.3 m. The plant's operating parameters are as follows: (i) (ii) (iii) (iv) (v) Flow = 0.0796 m³/s Soluble BOD, after primary settling = 130 mg/l MLVSS = 1500 mg/l MLSS=2100 mg/1 Settled sludge volume after 30 minutes = 230.0 ml/1 (a) Estimate the aeration period, F/M ratio, SVI, solids concentration in the return sludge. (b) It is desired that the soluble BOD, within the effluent leaving the plant be 8 mg/l. If the insoluble BOD, associated with the final effluent leaving the plant is 30% of the current NEPA TSS standard, what is the maximum BOD, expected in the final effluent stream for this well mixed activated sludge plant? Hint: Which metric discussed in class would best represent the period for which the wastewater is aerated?

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 F/M ratio 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 aeration time is nearly?
1. A wastewater is treated in an aerobic CSTR with no cell recycle. The following hold: Ks= 50mg/l; q^=5mg/mg VSSa-d; Kd= .06d-1; Y= 0.6; S°=220mg/l; fd= 1 a. Determine Ɵcmin, Ɵclim, Smin
8 Determine the solid loading rate on a secondary circular clarifier (diameter = 20 m) if the plant influent load is 2 ML/d. The recycle flow from secondary clarifier to the activated sludge system (aeration basin) is set to 10% of the influent load. It is also known that the aeration basin produces an MLSS (mixed liquor suspended solids) concentration of 3000 mg/L.
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1. A wastewater is treated in an aerobic CSTR with no cell recycle. The following hold: Ks= 50mg/l; q^=5mg/mg VSSa-d; Kd= .06d-1; Y= 0.6; S°=220mg/l; fd= 1
An aeration tank has an MLSS concentration of 2000 mg/L. After settling for 30 min. in a 1-L graduated cylinder, the sludge volume is measured to be 150 mL. Compute the SVI of the sludge.
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