A. By chemical coagulation
B. In sedimentation tanks equipped with mechanical scrapper
C. In vacuum filter
D. In clarifiers
Related Mcqs:
- Which of the following is the most efficient for removal of very finely divided suspended solids and colloidal matter from the polluted water stream ?
A. Sedimentation tank
B. Circular clarifier
C. Mechanical flocculation
D. Chemical coagulation - Suspended solid present in the waste water generated in blast furnace gas cooling and cleaning plant is removed by__________________?
A. Biological oxygen pond
B. Radial settling tank (thickener) using coagulant (lime & ferrous sulphate)
C. Lagoons
D. Filtration - Which is the most practical and economical method for removal of suspended solid matter from polluted water ?
A. Sedimentation
B. Skimming off
C. Chlorination
D. Biological oxidation - Which is the most efficient dust removal equipment for removal of submicronic dust particles from blast furnace gas ?
A. Packed scrubber
B. Gravity settling chamber
C. Electrostatic precipitator
D. Hydrocyclone - Brown spots in fabrics will be caused by washing with water containing large amount of___________________?
A. Iron
B. Zinc
C. Iodine
D. Bromine - Waste/polluted water discharged from electroplating, blast furnace and coal mining industries contain mainly _____________ substances?
A. Radioactive
B. Organic
C. Inorganic
D. None of these - Sooty and sulphurous smog formed due to combustion of fossil fuels particularly in winter, continues throughout the day and night. When the moist atmospheric air’s water vapor condenses on the solid particles of smoke thereby forming smog (smoke + fog), it causes_________________?
A. Poor visibility due to sky darkening
B. Irritation in eyes
C. Respiratory trouble
D. All A., B. and C. - Most efficient and suitable dust removal equipment for removal of fly-ash from flue gas in a thermal power plant is the__________________?
A. Gravity settling chamber
B. Cyclone separator
C. Electrostatic precipitator
D. Bag filter - Thermal pollution of water increases its toxicity and oxidation of oxygen demanding waste besides favouring bacterial growth. A rise in water temperature by 10°C, doubles the toxic effects of _____________ present in it?
A. Coal ash
B. Potassium cyanide
C. Ortho-xylene
D. None of these - The amount of chemical coagulant added for treatment of polluted water ______________ with increase in temperature of the polluted water to be treated?
A. Decreases
B. Increases
C. Remain constant
D. May increase or decrease; depends on the chemical characteristics of polluted water
