Page 2 - H.A-2 (PRACTICE WORKSHEET)

4. U 1
Which of the following is not an inorganic impurity
present in sewage?
a) Nitrate
b) Phosphate
c) Urea
d) Metal salt
5. Which of the following organisms produce biogas R 1
from the sludge?
a) Anearobic bacteria
b) Fungii
c) Aerobic bacteria
d) protozoans
6. Which of the following can be used to disinfect U 1
water in a seawge treatment plant?

A) Iodine B)Ozone

C) Oxygen D) chlorine

a) A and B
b) B and C
c) B and D
d) Only D

7. U 1
Which of the following statements are correct about
ozone?

A. It absorbs ultraviolet rays.
B. It iessential forbreathing.
C. It is used to disinfect water
D. It is proportion in air is about 3%

a) A and B
b) B and C
c) A and C
d) B and D
8. A sewage treatment plant involves the following R&U 3
steps:

Aeration tank

Grit removal tank

Sedimentation tank

Screening

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