In sewage treatment, its sedimentation is speeded up by commonly adding__________________?

Related Mcqs:

1. During sewage treatment, the sewage is subjected to ______________ treatment in Imhoff tank?

   A. Filtration
   B. Digestion
   C. Sedimentation
   D. Both B. and C.

2. ____________ substances present in sewage are removed in grit chamber during sewage treatment?

   A. Organic
   B. Fatty
   C. Inorganic
   D. Dissolved

3. Fine grit present in sewage is removed in the _____________ during sewage treatment?

   A. Grit chamber
   B. Detritus tank
   C. Trickling filter
   D. Skimming tank

4. The main type of sludge gas evolved during sewage treatment in Imhoff tank is___________________?

   A. CO2
   B. CH4
   C. CO
   D. H2

5. Which of the following processes is involved in the biochemical treatment of sewage effluents ?

   A. Oxidation
   B. Reduction
   C. Dehydration
   D. Fermentation

6. In sewage treatment, the detention period allowed for oxidation ponds ranges from _____________ weeks?

   A. 1 to 2
   B. 4 to 5
   C. 9 to 10
   D. 15 to 20

7. The type of bacteria which is active in trickling filter during biological treatment of sewage is the _____________ bacteria?

   A. Anaerobic
   B. Saprophytic
   C. Aerobic
   D. Parasitic

8. The function of skimming tank in sewage treatment is to remove _____________ substances?

   A. Dissolved solid
   B. Suspended solid
   C. Oil & fatty
   D. Gritty & inorganic

9. The most commonly used chemical coagulant in water treatment is________________?

   A. Ferrous sulphate
   B. Alum
   C. Lime
   D. Hydrazine

10. In a sedimentation tank, the detention period for water ranges from _____________ hours?

    A. 2 to 4
    B. 8 to 12
    C. 16 to 20
    D. 24 to 32