COD of raw municipal sewage may be in the range of about _____________ mg/litre?

Related Mcqs:

1. BOD of raw municipal sewage may be in the range of about _____________ mg/litre?

   A. 1-2
   B. 5-10
   C. 150-300
   D. 2000-3000

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

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

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

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

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

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

5. Presence of volatile compounds like gasoline, oil, alcohol, ether etc. in municipal sewers may cause___________________?

   A. Explosion
   B. Non biodegradable foam
   C. Undesirable plant growth
   D. Corrosion

6. Maximum permissible concentration (i.e. TLV) of DDT in public water supply system is _______________ micro gram (μ g)/litre?

   A. 22
   B. 42
   C. 332
   D. 1050

7. Which is the best and the most effective method for the removal of organic contaminant present in the polluted water in very small quantity (say < 200 mg/litre) ?

   A. Lagooning
   B. Activated carbon adsorption
   C. Biological oxidation pond
   D. Chemical coagulation

8. Maximum permissible residual chlorine in treated water should be ____________ mg/litre?

   A. 0.001 to 0.01
   B. 0.2 to 0.3
   C. 2 to 3
   D. 5 to 10

9. Phenolic water generated in coke ovens & by-product plant attached to an integrated steel plant containing phenol in concentration of less than 100 mg/litre can be removed by_______________?

   A. Chlorination
   B. Treating in biological oxygen pond
   C. Chemical coagulation
   D. None of these

10. TLV of aldrin in public water supply system is about ____________ μg/litre?

    A. 0.5
    B. 17
    C. 357
    D. 1097