Environmental Engineering - 1 - May 2014

Civil Engineering (Semester 6)

TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks. 1 (1) Explain the importance of environmental sanitation.(4 marks) 1 (2) Explain food chain and food web in relation to ecology.(4 marks) 1 (3) Explain the principle of sedimentation.(4 marks) 1 (4) Define potable water and state different types of pollution.(4 marks) 1 (5) State the significance of residual chlorine in drinking water. Explain the test performed in the laboratory for determining residual chlorine.(4 marks) 2 (1) A rectangular tank with length of 15 m, width of 6 m and depth 3 m into treat 2.40 × 10⁶ MLD. Calculate (1) Detention period of tank (2) Average flow velocity through tank (3) S.O.R.(10 marks) 2 (2) Briefly explain the different types of disinfectants used in water treatment stating the relative merits and situation where they are most suited.(10 marks) 3 (1) Draw the flow sheet showing sequence of various treatment units of a typical water treatment units of a typical water treatment plant with perennial river as the source of water. List these treatment units sequentially and state the function of each unit.(10 marks) 3 (2) Design a rapid sand filter to treat 2.25 MLD water supply for town. Given (i) filter works for 12 hours a day (ii) rate of filtration is 1250 MI/d/ha.(10 marks) 4 (1) Describe the operating problems of Rapid sand filter. Explain Negative head.(10 marks) 4 (2) How are impurities in water classified? What are their respective causes and their effects?(10 marks) 5 (1) Explain various methods to control leachate.(10 marks) 5 (2) Explain why chlorination is considered necessary even when filtration provided. Explain break point chlorination with diagram.(10 marks) 6 (1) Why are coagulants required in water treatment? What factors affect the dosage of coagulant?(10 marks) 6 (2) Define soft water. Write down the different methods of water softening. Explain a method of softening of water for industrial use.(10 marks)

Write any short notes on any four of the following

7 (1) Composting(5 marks) 7 (2) Hazardous waste.(5 marks) 7 (3) Iron and Manganese removal.(5 marks) 7 (4) Biochemical cyties.(5 marks) 7 (5) Fluoridation and de fluoridation.(5 marks)