111. If the average daily consumption of a city is 100,000 m3, the maximum daily con¬sumption on peak hourly demand will be_______________?
A. 100000m3
B. 150000m3
C. 180000m3
D. 270000 m3
✅ The correct answer is option D.
Environmental Engineering MCQs
112. In lime-soda process________________?
A. only carbonate hardness is removed
B. only non-carbonate hardness is re-moved
C. lime reduces the carbonate hardness and soda-ash removes the non-carbo¬nate hardness
D. lime reduces the non-carbonate hard-ness and soda-ash removes the carbo¬nate hardness
✅ The correct answer is option C.
113. The treatment of water with bleaching powder is known as________________?
A. prechlorination
B. super chlorination
C. dechlorination
D. hypochlorination
✅ The correct answer is option D.
114. The velocity of flow of water in a sedimentation tank is about__________________?
A. 5 to 10 cm/sec.
B. 15 to 30 cm/sec.
C. 15 to 30 cm/minute
D. 15 to 30 cm/hour
✅ The correct answer is option C.
115. The distribution mains are designed for________________?
A. maximum daily demand
B. maximum hourly demand
C. average daily demand
D. maximum hourly demand on maxi¬mum day
✅ The correct answer is option D.
116. If the sewage contains grease and fatty oils, these are removed in_________________?
A. grit chambers
B. detritus tanks
C. skimming tanks
D. sedimentation tanks
✅ The correct answer is option C.
117. Which of the following is not a water borne disease ?
A. dysentery
B. cholera
C. typhoid
D. maleria
✅ The correct answer is option D.
118. The design discharge for the combined sewer system shall be taken as________________?
A. equal to rainfall
B. rainfall + DWF
C. rainfall + 2 DWF
D. rainfall + 6 DWF
✅ The correct answer is option C.
119. If Biochemical oxygen demand (BOD. of a town is 20000 kg/day and BOD per capita per day is 0.05 kg, then population equivalent of town is_________________?
A. 1000
B. 4000
C. 100000
D. 400000
✅ The correct answer is option D.
120. In facultative stabilization pond, the sewage is treated by________________?
A. aerobic bacteria only
B. algae only
C. dual action of aerobic bacteria and anaerobic bacteria
D. sedimentation
✅ The correct answer is option C.