The ultimate BOD of the waste water whose 5 day BOD (BOD), and rate constant (base e) are respectively 150 mg/L and 0.23/day is (b) 150 mg/L (d) 220 mg/L (a) 80 mg/L (c) 180 mg/L

7235 A river before its entry into a town had a discharge of 100 litres per seconds and 20 mg/L as the concentration of a conservative parameter. The town's waste water outfall having 200 mg/L concentration of the same conservative parameter raised the river concentration of 50 mg/L after a complete mix with the river water. Determine the dilution ratio resulting from t said waste water outfall. discharge of the

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A wastewater sample was diluted 10% with tap water for conducting BOD Test. The DO content in wastewater sample was 1.2 mg/l and water was 6 mg/l. After 5 days incubation at 20°C, the DO of the sample was 0.5 mg/l. Calculate (i) 5 day BOD of wastewater and (ii) ultimate BOD. Assume K₂0 = 0.12/day. ion:

A wastewater sample of 2 ml is made up to 300 ml in a BOD bottle with distilled water. The initial D.O. of the sample is 8 mg/l and after 5 days it is 2mg/l. Its BOD is: 1. 6 mg/l 2. 894 mg/l 3. 2400 mg/l 4. 900 mg/l

PROBLEM #1 A stream receives a waste outfall which results in oxygen at saturation levels when mixed. The initial condition right after entry of the waste creates a BOD5 of 40 mg/l. KBOD is 0.3/day and KO2 is 1.3/ day. The stream temperature is 12 degrees centigrade. In terms of travel time when does the maximum DO sag occur? What is the minimum DO concentration in the river at the maximum sag point? If the average stream velocity is 3 feet per minute, what is the downstream location of the DO sag minimum relative to the location of the waste stream? Use the relevant equations provided in the textbook to solve this problem. Hint: Consider carefully what was stated in class about the BOD input for this type of problem.

If the BOD3 of a wastewater sample is 75 mg/l and reaction rate constant k (base e) is 0.345 per day, the amount of BOD remaining in the given sample after 10 days is 1. 3.21 mg/L 2. 3.45 mg/L 3. 3.69 mg/L 4. 3.92 mg/L

QUESTION: An aerated lagoon wastewater treatment is to be designed for a municipal wastewater. The design population is 5000 persons, and the aerated lagoon is to provide secondary treatment. Pertinent data are: flow = 380 L/cap-d, influent BOD5 = 255 mg/L; effluent BOD5 = 20 mg/L, K = 2.18 d-1 oxygen required 1.6 kg O2/kg BOD5 applied to the lagoons, and the primary clarifier removes 33 % of the influent BOD5. Calculate the total lagoon volume (m3)

Answer question 13

If the BOD3 of a wastewater sample is 75 mg/l and reaction rate constantk (base e) is 0.345 per day, the amount of BOD remaining in the given sample after 10 days is