Grit is composed of
(1) Soil
(2) Small pebbles
(3) Both A and B
(4) Human excreta+ soil+ small pebbles
Removal of grit is carried out by
(1) Sedimentation
(2) Filteration
(3) Primary digestion
(4) Secondary digestion
The result of sedimentation results in settled solids which is known as
(1) Effluent
(2) Primary sludge
(3) Activator
(4) Both B and C
Effluent is formed in
(1) Primary Settling tank
(2) Colony sewage
(3) Secondary Settling tank
(4) Both B and C
The Biological treatment of sewage is also known as
(1) Secondary Treatment
(2) Primary Treatment
(3) Same treatment
(4) Floc treatment
In Biological treatment, the primary effluent is passed into
(1) Large aeration tank
(2) Large anaerobic tank
(3) Small aerobic Chambers
(4) Large anaerobic Chambers
Flocs are
(1) Masses of fungal Filaments associated with bacteria
(2) Masses of bacteria associated with fungal Filaments
(3) Masses of algae associated with fungal Filaments
(4) Masses of algae and bacteria
The growth of Flocs is facilitated by
(1) Constant agitation mechanically
(2) Air is pumped
(3) Both A and B
(4) Filaments of algae
The significance of Flocs in secondary Treatment is not
(1) Consumption of organic matter
(2) Reduction of BOD
(3) Reduction in polluting potential
(4) Reduction of inorganic salts
BOD is
(1) Amount of oxygen taken by bacteria to survive in 100mL water
(2) Amount of oxygen taken by bacteria to oxidise organic matter in 1L of water
(3) Amount of oxygen taken by bacteria to oxidise inorganic matter in 100mL of water
(4) Amount of oxygen evolved by bacteria to oxidise organic matter of 1L water