1) Estimate the biomass concentration in a CSTR aeration tank with the following operating conditions: hydraulic residence time = 3 h; mean cell residence time = 6 d; yield coefficient = 0.6 mg VSS/mg BOD; decay rate = 0.1 d-1; influent soluble BOD = 200 mg/L; effluent BOD = 2 mg/L.

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Q: The initial ultimate BOD after mixing of the James River is 32.5 mg/L. The DO in the river after the…

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Q: 1. The required reactor detention time, 0. 2. The reactor basin volume, V, in m³. 3. The net waste…

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Q: (a) Determine the size range for the various fractions obtained during settling.

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Q: Some waste has a five-day BOD at 20 °C equal to 210 mg/L and an ultimate OD of 350 mg/L. Find the…

A: Given data :BOD at 20oC is (L) = 210mg/LUltimate BOD at 20oC is (L) = 350mg/L

Q: Biochemical Oxygen Demand A water sample was incubated at 20 °C for 3 days and its BOD3…

A: Using formula to find ultimate BOD

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Q: . The analysis of a hard water shows the following compositions: = 3 mg/l = 68 mg/l = 92 mgll 15…

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Q: Using Rihet equation, estimate aeration tank Volume (V) based on the following conditions:…

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Q: 6. A tertiary treatment plant treats a municipal secondary effluent and is to employ fixed-bed…

A: Reference : Environmental Engineering, Waste water treatment plant. Given : Flow, COD, Contact time…

Q: b. Find the DO at 12 10. A water treatment plant treats the water at the rate of 33 MGD. Average…

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Q: A secondary treatment using a mixed water activated sludge system, have the flow rate of…

A: simple activated sludge process diagram and their simple formula

Q: A bio-tower composed of a modular plastic medium of 6 m is used as secondary treatment component in…

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Q: quantity of water to be treated is 2 MGD. i Estimate the total hardness, carbonate hardness and…

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Q: A completely mixed activated sludge process operating at equilibrium is designed to treat 300 MLD of…

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Q: Microbial growth in an activated sludge system can be described by the Monod model. If the maximum…

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Q: For an industrial activated sludge treatment process, the biomass concentration (X) is 2,200 mg…

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Q: A Granulated Activated Carbon (GAC) adsorption laboratory column 10cm in diameter and 3m deep, is…

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Q: . Assume that low values of Kow are <10. Provide a relativ efficiency for SVE treatment. Log Kow

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Q: A groundwater borehole at USM engineering campus contains 3000 mg/L of TDS. The flow is 0.32 m³/s.…

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Biological Processes

Biological solid waste includes bacterial and contaminated waste produced by living individuals. Its treatment is essential to prevent the spread of any air-borne or water-borne diseases or diseases transmitted from one organism to another in a food chain. There are many benefits of the biological solid waste treatment and some of them are: the minimized quantity of waste substance, waste control, eradicating any disease-causing pathogens, generation of biogas, composting, anaerobic digestion, bio drying, mechanical biological treatment, microbial fuel cell, phytoremediation, and biofiltration. The final products of the biological solid waste treatment may be recycled to obtain organic fertilizers or disposed of in SWDS (Solid Waste Disposal Site) after proper treatment.