A. Bacterial stability factor
B. Relative stability
C. Biological oxygen demand (BOD)
D. Oxygen ion concentration
Related Mcqs:
- 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 nitrogen in high concentration in contaminated air reduces partial pressure of oxygen in lungs, thereby causing asphyxia (suffocation) leading to death from oxygen deficiency. Concentration of N2 in contaminated air at which it acts as a natural asphyxiate is ≥ _____________ percent?
A. 84
B. 88
C. 80
D. 92 - The function of skimming tank in sewage treatment is to remove _____________ substances?
A. Dissolved solid
B. Suspended solid
C. Oil & fatty
D. Gritty & inorganic - A shallow pond in which the sewage is retained and biologically treated is called__________________?
A. Oxidation
B. Imhoff tank
C. Lagoon
D. Skimming tank - The pH value of oxidised sewage is about_____________________?
A. 1.8
B. 6.2
C. 7.3
D. 13.4 - Fresh domestic sewage is _______________ in color?
A. Grey
B. Dark brown
C. Red
D. Black - Which of the following processes is involved in the biochemical treatment of sewage effluents ?
A. Oxidation
B. Reduction
C. Dehydration
D. Fermentation - 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