(b) Consider the following data for a completely mixed activated sludge system to treat wastewater from a community of 60000 persons: Sewage flow, Q = 9000 m³/day BOD = 360 mg/l (raw) Assume 30% BOD removal in primary settling and 90% in biological treatment. Winter temperature of mixed liquor = 10°C Yield, y = 0.6 k = 0.07/day (BOD, basis at 15°C) VSS MLSS=4000 mg/1, SS Adopt sludge age (0) = 10 days Determine F/M ratio and oxygen requirement uptake per day for this completely mixed activated sludge system. = 0.8

(b) Consider the following data for a completely mixed activated sludge system to treat wastewater from a community of 60000 persons: Sewage flow, Q = 9000 m³/day BOD = 360 mg/l (raw) Assume 30% BOD removal in primary settling and 90% in biological treatment. Winter temperature of mixed liquor = 10°C Yield, y = 0.6 k = 0.07/day (BOD, basis at 15°C) VSS MLSS=4000 mg/1, SS Adopt sludge age (0) = 10 days Determine F/M ratio and oxygen requirement uptake per day for this completely mixed activated sludge system. = 0.8

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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Problem 1. A wastewater sample is examined for its solid contents. The ionic strength (μ) of wastewater is 0.01. It is known that 30% of total dissolved solids (TDS) is organic. The volumetric settleable solid concentration is determined as 20 mL/L using Imhoff Cone. It is assumed that 40% of total suspended solids (TSS) is equal to dry-settleable solids. The volumetric settleable solids composes of 2% of dried solids and 98% of water. The density of volumetric settleable solid concentration is given as 1020 g/L. Use information given in problem, calculate: a) Total Dissolved Solids (TDS) concentration as mg/L. b) Total Suspended Solids (TSS) concentration as mg/L. c) Total Solids (TS) concentration as mg/L.
C. What is the concentration UI SUINUS 5. Determine the size (diameter and depth) of the secondary clarifier (s) at a municipal activated sludge treatment facility: The wastewater flow is 25,000 m³/d, the recycle ratio (recycle sludge flow/wastewater flow) is 0.25. The suspended solids concentration is assumed to be 2500 mg/L in the activated sludge tank. The over flow rate is 50 m3/d- m2 and solids loading is 125 kg/d-m2. Estimate detention time if the depth is 4.5 m. What would be the weir loading? Department of Civil & Environmental Engineering P.O. Box 519 Mail Stop 2510, Prairie View, Texas 77446 w.pvamu.edu Phone (936) 261-1660/1665(dept) Fax (936) 261 1662 Ensuring o Using Zoom o
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