Centurion University of Technology and Management PARALAKHEMUNDI

SUB: ENVIRONMENTAL ENGINEERINGMID TEST-II, 8TH SEM (CSE/IT/Mech)

Time: 1Hr Full marks: 20SECTION-A (Answer any 5) 2X5=10

1. Differentiate between primary and secondary pollutants with examples.2. What is F/M ratio?3. Differentiate between BOD5 & ultimate BOD.4. Write about the aquatic pollutants responsible for aquatic pollution.5. Write about acid rain.6. List out some criteria and non criteria pollutants.

SECTION-B (Answer any 2) 5X2=10

1. Describe the main classes of pollutants in estuaries and marine environment.2. Explain activated sludge process of waste water treatment with neat a labeled

diagram.3. A wastewater with a BOD of 25 mg/L is discharged through an outfall to a

freshwater stream of mean velocity 0.1 m/s. The DO upstream of the outfall is 8.5 mg/L. Assuming the deoxygenation rate K1 =0.25 d-1 and the reaeration rate K2 =0.4 d-1 , determine (a) the time and distance downstream (xc) where DO is a minimum and (b) the minimum DO.[Given, saturation DO=9.2 mg/L]