A. Filtration
B. Digestion
C. Sedimentation
D. Both B. and C.
Related Mcqs:
- The main type of sludge gas evolved during sewage treatment in Imhoff tank is___________________?
A. CO2
B. CH4
C. CO
D. H2 - ____________ substances present in sewage are removed in grit chamber during sewage treatment?
A. Organic
B. Fatty
C. Inorganic
D. Dissolved - Fine grit present in sewage is removed in the _____________ during sewage treatment?
A. Grit chamber
B. Detritus tank
C. Trickling filter
D. Skimming tank - The function of skimming tank in sewage treatment is to remove _____________ substances?
A. Dissolved solid
B. Suspended solid
C. Oil & fatty
D. Gritty & inorganic - 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 - Which of the following processes is involved in the biochemical treatment of sewage effluents ?
A. Oxidation
B. Reduction
C. Dehydration
D. Fermentation - 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 - In sewage treatment, its sedimentation is speeded up by commonly adding__________________?
A. Hydrochloric acid
B. Lime
C. Copper sulphate
D. Sodium sulphate - A solid metallic block weighing 5 kg has an initial temperature of 500°C. 40 kg of water initially at 25°C is contained in a perfectly insulated tank. The metallic block is brought into contact with water. Both of them come to equilibrium. Specific heat of block material is 0.4 kJ.kg-1. K-1. Ignoring the effect of expansion and contraction and also the heat capacity to tank, the total entropy change in kJ.kg-1, K-1 is_________________?
A. -1.87
B. 0
C. 1.26
D. 3.91 - Fresh sewage is ______________ in nature?
A. Acidic
B. Neutral
C. Alkaline
D. Highly acidic