A. 1-2
B. 5-10
C. 90-120
D. 1500-2500
Related Mcqs:
- 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 - Fine grit present in sewage is removed in the _____________ during sewage treatment?
A. Grit chamber
B. Detritus tank
C. Trickling filter
D. Skimming tank - During sewage treatment, the sewage is subjected to ______________ treatment in Imhoff tank?
A. Filtration
B. Digestion
C. Sedimentation
D. Both B. and C. - ____________ substances present in sewage are removed in grit chamber during sewage treatment?
A. Organic
B. Fatty
C. Inorganic
D. Dissolved - 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 - 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 - 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 - 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 - 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 - TLV of aldrin in public water supply system is about ____________ μg/litre?
A. 0.5
B. 17
C. 357
D. 1097
