Engineering, 08.04.2021 15:40 dchannakhone84

A standard seeded BOD5 test was conducted in a laboratory. It was revealed that the initial DO concentration in a BOD bottle which had been filled with 8 mL of wastewater sample and 292 mL of seeded dilution water was 8.9 mg/L just after preparation. After an incubation period of five days, the final DO concentration was reported as 1.4 mg/L. Meanwhile, DO concentration in the control bottle with seeded dilution water decreased from 9.0 to 8.8 mg/L within five days. a) What is the 5-day BOD of the wastewater sample? b) What would be the 5-day BOD of the wastewater sample if the technician tested the wastewater with the same dilution, this time without seeding, and found out that the DO changed from 8.9 to 1.4 mg/L again? c) Considering both results obtained in (a) and (b), what kind of wastewater do you think the sample belongs to? Discuss your answer. (Hint: Make sure to keep the P and f as ratios (without rounding off) until the end of the calculation.)

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A standard seeded BOD5 test was conducted in a laboratory. It was revealed that the initial DO conce...

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