Environmental Engineering - 2 - December 2015

MU Civil Engineering (Semester 7)

Total marks: --
Total time: -- INSTRUCTIONS
(1) Assume appropriate data and state your reasons
(2) Marks are given to the right of every question
(3) Draw neat diagrams wherever necessary 1 (a) State principles governing design of building drainage. 5 marks

1 (b) List various control measures of air pollution. 5 marks

1 (c) Compare one pipe and two pipe system. 5 marks

1 (d) The CO content of an air sample is 90μ/m³ at 0°C and 1 atm. Pressure. Convert it to PPM. Assume necessary data. 5 marks

2 (a) Draw a neat sketch of automatic flushing tank and explain the operation of flushing. 5 marks

2 (b) Design imhoff tank for 25000 people and sewage flow 180 lpcd. Assume data. 5 marks

2 (c) Explain the biological action and processor of sludge digestion. 5 marks

3 (a) Why de-watering of sludge is necessary? Explain the method of de-watering the sludge on sludge drying beds. 5 marks

3 (b) What are the basic differences between aerobic and anaerobic processes. 5 marks

3 (c) If 5 day 20° c BOD of waste water is 350 mg/l, what will be the its's 7 days, 25° C BOD? K₂₀=0.1/d. Assume data if required. 5 marks

4 (a) Draw the flow chart of the municipal sewage treatment plant by using activated Sludge process and trickling filter. 5 marks

4 (b) Determine the size of high rate trickling filter for the following data:
i) Sewage flow 4 M.L.D.
ii) Recirculation ratio = 1.5
iii) BOD5 of raw sewage: 280 mg/1
iv) BOD removal in PST=25%
v) Final effluent BOD5 desired = 30 mg/l. 5 marks

5 (a) Explain in detail with sketch sedimentation tank and its design parameters. 5 marks

5 (b) Find the volume of digester for population equivalent -7000, loading rate -0.09 kg/capita/day, volatile solids in raw sludge -70%, moisture content of raw sludge -96%, digestion period -25 days, volatile solids reduction during digestion -50%, moisture content of digested sludge -92%, storage period required for digested sludge -90 days. 5 marks

5 (c) What is biological treatment process? Explain aerobic and anaerobic process in detail. 5 marks

6 (a) Explain intercepting trap in detail. 5 marks

6 (b) Explain construction of sewers and steps involved in laying of it. 5 marks

6 (c) A 30 cm dia sewer having an invert slope of 1:200 was flowing full. What would be velocity of flow and discharge? (n=0.013). Is the velocity self-cleasing? What would be velocity and discharge, when the same is flowing 0.2 and 0.8 of its full depth?