Total No. of Questions 10]
[Total No. of Pages 3
[5353] 110
T.E. (Civil) End Semester
ENVIRONMENTAL ENGINEERING I
(2012 Pattern)
Time :2½ hours] [Max. Marks :70
Instructions to the candidates:
Attempt Q.1 or Q.2, Q.3 or Q.4, Q.5 or Q.6, Q.7 or Q.8, and Q.9or Q.10
Figures to the right indicates full marks
Draw neat figures wherever necessary
Assume necessary data
Use of scientific calculators is allowed
P3247
SEAT No.
P.T.O.
[5353] 110 2
Q4) A circular sedimentation tank fitted with standard mechanical sludge
removal equipment is to handle 3 MLD of raw water. If the detention
period of the tank is 4 hours and the depth of the tank is 3 m. What
should be the diameter of the tank?
Draw the schematic sketch of river intake and canal intake.
Q5) What are the factors on which dose of coagulants depends? Explain
how the optimum coagulant dose is determined?
Design a circular flocculator for a design discharge of 3 MLD with
mechanical paddle and detention period of 30 minutes. Depth of basin is
3 m,area of paddles is 20 of vertical cross section.
Write working principle of pressure filter, draw its schematic sketch and
write its advantages.
OR
Q6) A filter unit is 4 m by 9m. After filtering 10000m3/d in 24 hour period, the
filter water is backwashed at a rate of 10 lit/m2/ sec for 30 minutes.
Calculate the average filtration rate, quantity and percentage of treated
water used in washing and the rate of wash water flow in each trough.
Assume 4 troughs.
Explain the theory of coagulation. Give the chemical equation of
coagulation by alum.
Differentiate between slow sand filter and rapid sand filter.
Q7) Define break point chlorination and explain how it is determined.
Explain hardness removal by zeolite process.
Explain removal of colour and odour by adsorption phenomena.
OR
Q8) The water works of a town of population 200000 has to meet its water
demand at the rate of 150 lit/c/d. If the disinfection is to be done by
bleaching powder having 45% available chlorine, determine the quantity
of bleaching powder required per year. The required dose of chlorine at
the water work is 0.3 ppm for disinfection.
Write principle, advantages and disadvantages of electro dialysis for
demineralization of water.
Write factors affecting disinfection.
[5353] 110 3
Q9) Deigned demand of town is 3 MLD. It is pumped into an elevated service
reservoir at a uniform rate from 5am to 9 am 5pm to 9pm. The variation
in consumption of water is given below.
Period 5am to 9 am to 5pmto 9pm to 12am to
9am 5pm 9pm 12am 5am
Consumption 40% 15% 30% 10% 05%
Determine the balancing capacity of the reservoir.
Draw a flowchart of package water treatment plant and write its
advantages.
Write difference between continuous and intermittent system.
OR
Q10)a) Calculate the storage capacity and dimensions of the tank to store rain
water for the given data:
Terrace area 200 m2, average annual rainfall 720 mm and runoff
coefficient 0.8.
Consider Length 2 x width and depth 2 m.
Write methods to detect the wastage of water and its prevention.
Draw a schematic sketch of rooftop rain water harvesting system and
write its components.